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Sample records for autograft implantation system

  1. Placement of implant bridge anterior maxilla post autograft (Serial case

    Directory of Open Access Journals (Sweden)

    Rifaat Nurrahma

    2016-06-01

    Full Text Available An advanced technology with implants based has now been developed in recent years.Implant with the bridge superstructure method is employed after variety of considerations where it is expected to meet its function, aesthetics, and comfortability.The alveolar bone existed is one reason for the process of adding bone (bonegraft.This case report proposes to determine the successful insertion of a superstructure anterior implant bridge post autograft.Two female patients were asked to use dental implant anterior with bridge system.The first case, the autograft application is made for a 20-year-old woman with edentulous teeth 11, 21, 22. One year later it was then inserted in the area of dental implant fixture 11 and 22. After 9 months, the healing abutments and the superstructure were inserted too.2 weeks after, the abutments of bridge and crowns of teeth 11, 21 and 22 with a pontic in the teeth 21 had been inserted. The second case, a 46-year-old woman with edentulous 11,12,21,22.They want to change the denture because they did not feel comfortable with the removable denture acrylic.Fixture placement was done a year after autograft.Insertion of healing abutments and the superstructure printing can be done after 6 months.A month later implant abutments and crowns could be inserted.Labial fullness is corrected; an implant-retained in the region of 12 and 21, 12, and 22 used the pontic.Prosthodontic rehabilitation with a fixed denture using the implant bridge after autograft anterior maxilla is an alternative fixed denture placement with satisfactory results, aesthetic correction and comfortably.

  2. Aortic root reoperations after pulmonary autograft implantation

    NARCIS (Netherlands)

    J.A. Bekkers (Jos); L.M.A. Klieverik (Loes Maria Anne); G. Bol-Raap (Goris); J.J.M. Takkenberg (Hanneke); A.J.J.C. Bogers (Ad)

    2010-01-01

    textabstractObjective: To report the results of aortic root reoperations after pulmonary autograft implantation. Methods: All consecutive patients in our prospective Ross research database were selected for analysis, and additional information for patients requiring reoperation was obtained from the

  3. Inverse Implantation and Rapid Postoperative Necrosis of Conjunctival Autograft in Pterygium Surgery

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    Murat Küçükevcilioğlu

    2012-07-01

    Full Text Available A 72 year-old female underwent surgery for nasal pterygium in the right eye. Conjunctival autograft with Mytomycine-C was performed. In the postoperative period slit lamp examination revealed a pale and avascular appearance of the conjunctival graft. On postoperative fifth day inverse graft implantation and graft necrosis was diagnosed. The graft was removed. We herein discuss the reason and possible preventive measures of this unusual outcome. (Turk J Oph thal mol 2012; 42: 298-9

  4. Ectopic bone formation in bone marrow stem cell seeded calcium phosphate scaffolds as compared to autograft and (cell seeded allograft

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    J O Eniwumide

    2007-08-01

    Full Text Available Improvements to current therapeutic strategies are needed for the treatment of skeletal defects. Bone tissue engineering offers potential advantages to these strategies. In this study, ectopic bone formation in a range of scaffolds was assessed. Vital autograft and devitalised allograft served as controls and the experimental groups comprised autologous bone marrow derived stem cell seeded allograft, biphasic calcium phosphate (BCP and tricalcium phosphate (TCP, respectively. All implants were implanted in the back muscle of adult Dutch milk goats for 12 weeks. Micro-computed tomography (µCT analysis and histomorphometry was performed to evaluate and quantify ectopic bone formation. In good agreement, both µCT and histomorphometric analysis demonstrated a significant increase in bone formation by cell-seeded calcium phosphate scaffolds as compared to the autograft, allograft and cell-seeded allograft implants. An extensive resorption of the autograft, allograft and cell-seeded allograft implants was observed by histology and confirmed by histomorphometry. Cell-seeded TCP implants also showed distinct signs of degradation with histomorphometry and µCT, while the degradation of the cell-seeded BCP implants was negligible. These results indicate that cell-seeded calcium phosphate scaffolds are superior to autograft, allograft or cell-seeded allograft in terms of bone formation at ectopic implantation sites. In addition, the usefulness of µCT for the efficient and non-destructive analysis of mineralised bone and calcium phosphate scaffold was demonstrated.

  5. Valve-sparing root replacement for freestanding pulmonary autograft aneurysm after the Ross procedure.

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    Ratschiller, Thomas; Eva, Sames-Dolzer; Schimetta, Wolfgang; Paulus, Patrick; Müller, Hannes; Zierer, Andreas; Mair, Rudolf

    2018-02-20

    Autograft dilatation is the main long-term complication following the Ross procedure using the freestanding root replacement technique. We reviewed our 25-year experience with the Ross procedure with a special emphasis on valve-sparing reoperations. From 1991 to 2016, 153 patients (29.6 ± 16.6 years; 29.4% pediatric) underwent a Ross operation at our institution with implantation of the autograft as freestanding root replacement. The follow-up is 98.7% complete with a mean of 12.2 ± 5.5 years. Mortality at 30-days was 2.0%. Echocardiography documented no or trivial aortic regurgitation in 99.3% of the patients at discharge. Survival probability at 20 years was 85.4%. No case of autograft endocarditis occurred. Autograft deterioration rate was 2.01% per patient-year, and freedom from autograft reoperation was 75.3% at 15 years. A reoperation for autograft aneurysm was required in 35 patients (22.9%) at a mean interval of 11.1 ± 4.6 years after the Ross procedure. A valve-sparing root replacement was performed in 77% of patients, including 10 David and 17 Yacoub procedures with no early mortality. Three patients required prosthetic valve replacement within 2 years after a Yacoub operation. At latest follow-up, 92% of all surviving patients still carry the pulmonary autograft valve. Freedom from autograft valve replacement was 92.1% at 15 years. Using the David or Yacoub techniques, the autograft valve can be preserved in the majority of patients with root aneurysms after the Ross procedure. Reoperations can be performed with no early mortality, a good functional midterm result, and an acceptable reintervention rate. Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  6. Viability of osteocytes in bone autografts harvested for dental implantology

    International Nuclear Information System (INIS)

    Guillaume, Bernard; Gaudin, Christine; Georgeault, Sonia; Mallet, Romain; Basle, Michel F; Chappard, Daniel

    2009-01-01

    Bone autograft remains a very useful and popular way for filling bone defects. In maxillofacial surgery or implantology, it is used to increase the volume of the maxilla or mandible before placing dental implants. Because there is a noticeable delay between harvesting the graft and its insertion in the receiver site, we evaluated the morphologic changes at the light and transmission electron microscopy levels. Five patients having an autograft (bone harvested from the chin) were enrolled in the study. A small fragment of the graft was immediately fixed after harvesting and a second one was similarly processed at the end of the grafting period when bone has been stored at room temperature for a 20 min ± 33 s period in saline. A net increase in the number of osteocyte lacunae filled with cellular debris was observed (+41.5%). However no cytologic alteration could be observed in the remaining osteocytes. The viability of these cells is known to contribute to the success of autograft in association with other less well-identified factors.

  7. The use of dermal autograft as an adjunct to breast reconstruction with tissue expanders.

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    Rinker, Brian

    2012-12-01

    Acellular dermal matrices are commonly used in breast reconstruction but add cost to the procedure and have been associated with complications. Dermal autograft may represent a useful alternative to matrices. Sixteen patients (26 breasts) underwent breast reconstruction using tissue expanders and dermal autograft. Their ages ranged from 41 to 66 years (median, 51 years). Autografts were harvested by wide excision of preexisting abdominal scars. Demographic data, clinical history, and harvest and preparation time were recorded. The initial fill volume, number of expansions, and complications were recorded and compared with published data for acellular dermal matrix-assisted reconstruction. Patients rated their satisfaction with scar appearance on a seven-point scale. Follow-up ranged from 6 to 16 months (mean, 10 months). Three patients were smokers. Mean body mass index was 30.5 (range, 19.1 to 48.8). Three patients received chemotherapy between reconstructive stages, and none required irradiation. The mean time of autograft harvest was 38 minutes, the mean initial fill was 190 cc, and the average number of expansions was 3.5. There were no implant losses. There were three minor complications (19 percent). Initial expander fill, number of expansions, and complication rate were equivalent to historical values for matrix-assisted breast reconstruction. Fourteen of 16 patients (88 percent) were "very satisfied" with their scars. The use of dermal autograft in tissue expander breast reconstruction offers the advantages of acellular dermal matrix, without the associated expense. The technique adds minimally to the operative time and morbidity and is associated with a low complication rate. Therapeutic, IV.

  8. [Experimental work: reconstruction of the pelvi-ureteric junction and ureter using testicular tunica vaginalis autograft].

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    Usupbaev, A Ch; Kurbanaliev, R M; Chernetsova, G S; Kolesnichenko, I V; Sultanov, B M; Myrzakanov, N M; Zolotukhin, A O; Vagner, N A

    2017-12-01

    To evaluate the results of surgical reconstruction of the upper urinary tract using an autograft of testicular tunica vaginalis in experimental animals. The article presents the results of partial replacement of the renal pelvis and ureter with an autograft in 25 male dogs. The grafts were harvested by resection of the parietal layer of the testicular tunica vaginalis, which was transplanted into the region of the pelvi-ureteric junction and the proximal ureter. The upper urinary tract was drained using a ureteral stent catheter. The results were evaluated at week 1 and months 1, 3 and six after the operation. The functional state of the kidneys and ureters was analyzed using excretory urography and ultrasound; the autograft biopsy specimens were examined histologically. In all cases, the viability of the autograft was completely preserved, there were no signs of secondary infection, necrosis and impaired patency in the anastomosis zone. Histological examination revealed signs of epithelialization, connective tissue substitution and neovasculogenesis in the implantation zone. The proposed surgical modality is an alternative method to restore normal urine flow in the upper urinary tract in obstructive urological diseases. The group of obstructive urological diseases was studied using the model of the strictures of the pelvi-ureteric junction in the intrarenal pelvis and ureteral strictures measuring up to 3-4 cm in length.

  9. MRI of anterior cruciate ligament autografts

    International Nuclear Information System (INIS)

    Ogi, Shigeyuki; Ariizumi, Mitsuko; Yamagishi, Tsuneo; Agata, Toshihiko; Tada, Shinpei; Fukuda, Kunihiko

    2000-01-01

    The purpose of this study was to assess the usefulness of MRI in the evaluation of autografts after anterior cruciate ligament reconstruction. The subjects were 110 patients with anterior cruciate ligament reconstruction using patellar tendon autografts who underwent clinical examination, MRI, and arthroscopy of the knee. T1- and T2-weighted MR images were obtained in sagittal plane. Clinical findings were categorized into three groups: normal, borderline, and abnormal. The MRI appearances of the autografts were categorized into three types: straight continuous band (type I), interrupted band (type II) and generalized increased intensity band (type III). The clinical findings and MRI findings were compared with arthroscopic findings. Ninety-six percent of the type I showed no autograft tear on arthroscopy. In comparison with the clinical findings, MRI was found to be well correlated with arthroscopic findings. In conclusion, if the clinical findings are normal, patients are to be followed-up without MRI and arthroscopy. However, if clinical findings are either borderline or abnormal, MRI should be performed prior to arthroscopy. (author)

  10. [Biomaterials for bone filling: comparisons between autograft, hydroxyapatite and one highly purified bovine xenograft].

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    Chappard, D; Zhioua, A; Grizon, F; Basle, M F; Rebel, A

    1993-12-01

    Bone grafts are becoming increasingly common in orthopaedics, neurosurgery and periodontology. Twenty one New Zealand rabbits were used in the present study comparing several materials usable as bone substitutes. A 4.5 mm hole was drilled in the inner femoral condyles. Holes were filled with either an autograft (from the opposite condyle), an hydroxylapatite (Bioapatite), or a highly purified bovine xenograft (T650 Lubboc). Animals were sacrificed at 1, 3 and 6 months post implantation and a quantitative analysis of newly-formed bone volume (BNF/IV) and remaining biomaterials (BMAT/IV) was done. In addition, some holes were left unfilled and served as controls. At 6 months, there was no tendency for spontaneous repair in the control animals. The autografted animals have repaired their trabecular mass and architecture within the first month. Hydroxylapatite appeared unresorbed at six months and only thin and scanty new trabeculae were observed. The xenograft induced woven bone trabeculae formation on the first month. This was associated with resorption of the material by two multinucleated cell populations. At six months, the epiphyseal architecture was restored and the biomaterial has disappeared in most cases. Xenografts appear a promising alternative to autografts and allografts, whose infectious risks and ethical problems should always be borne in mind.

  11. Outcomes of Reintervention on the Autograft After Ross Procedure.

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    Kumar, S Ram; Bansal, Neeraj; Wells, Winfield J; Starnes, Vaughn A

    2016-11-01

    After a Ross procedure, a small subset of patients requires reintervention for autograft dilatation or valve insufficiency. We sought to determine the indications, nature, and outcomes of autograft reinterventions in the left ventricular outflow tract after a Ross procedure. We retrospectively reviewed the charts of 316 consecutive patients, age 4 days to 70 years, who underwent a Ross procedure at our institution. Of these, 47 patients (15%) required autograft reintervention during a median follow-up of 8.2 years. Forty-seven patients, median age 26 years (interquartile range [IQR], 14.4 to 44.8 years), 32 (68%) men, required autograft reintervention a median 5.5 years (IQR, 1.8 to 9.4 years) after a Ross procedure. In 47% (22 of 47 patients), the autograft valve could be salvaged (15 valve-sparing aortic replacements, 7 valve repairs). The remaining 53% underwent replacement of the root (10 mechanical, 5 homograft) or valve alone (7 mechanical, 3 bioprosthetic). Twenty patients presented without autograft root dilatation 1 year (IQR, 0.5 to 2.9 years) after Ross. Fifteen of them (75%) required valve replacement. The 27 patients who demonstrated root dilatation presented 6.9 years (IQR, 4.5 to 9.7 years; p Ross, and 17 (63%) of these valves could be spared (p = 0.01). There was no surgical mortality and 5 (11%) major morbidity events. Patients were followed up for 4.9 years (IQR, 2.1 to 7 years) after left ventricular outflow tract reintervention. For patients whose autograft valve could be spared, 3-, 5-, and 8-year freedom from valve replacement was 92%, 86%, and 86%, respectively. At last follow-up, only 1 patient had greater than mild aortic insufficiency, and all but 1 had normal ejection fraction. Autograft reintervention after a Ross appears to follow a bimodal distribution. Patients with primary autograft leaflet problems tend to present early without root dilatation and frequently require valve replacement. The autograft valve can be salvaged in the

  12. Iliotibial band autograft versus bone-patella-tendon-bone autograft, a possible alternative for ACL reconstruction

    DEFF Research Database (Denmark)

    Stensbirk, Frederik; Thorborg, Kristian; Konradsen, Lars

    2014-01-01

    PURPOSE: The long-term results after using the iliotibial band autograft (ITB) in anterior cruciate ligament (ACL) reconstruction are not fully known. If equal in quality to conventional methods, the ITB graft could be a useful alternative as a primary graft, in revision surgery or multi-ligament......PURPOSE: The long-term results after using the iliotibial band autograft (ITB) in anterior cruciate ligament (ACL) reconstruction are not fully known. If equal in quality to conventional methods, the ITB graft could be a useful alternative as a primary graft, in revision surgery or multi...

  13. Iliac crest autograft versus alternative constructs for anterior cervical spine surgery: Pros, cons, and costs

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    Epstein, Nancy E.

    2012-01-01

    Background: Grafting choices available for performing anterior cervical diskectomy/fusion (ACDF) procedures have become a major concern for spinal surgeons, and their institutions. The “gold standard”, iliac crest autograft, may still be the best and least expensive grafting option; it deserves to be reassessed along with the pros, cons, and costs for alternative grafts/spacers. Methods: Although single or multilevel ACDF have utilized iliac crest autograft for decades, the implant industry now offers multiple alternative grafting and spacer devices; (allografts, cages, polyether-etherketone (PEEK) amongst others). While most studies have focused on fusion rates and clinical outcomes following ACDF, few have analyzed the “value-added” of these various constructs (e.g. safety/efficacy, risks/complications, costs). Results: The majority of studies document 95%-100% fusion rates when iliac crest autograft is utilized to perform single level ACDF (X-ray or CT confirmed at 6-12 postoperative months). Although many allograft studies similarly quote 90%-100% fusion rates (X-ray alone confirmed at 6-12 postoperative months), a recent “post hoc analysis of data from a prospective multicenter trial” (Riew KD et. al., CSRS Abstract Dec. 2011; unpublished) revealed a much higher delayed fusion rate using allografts at one year 55.7%, 2 years 87%, and four years 92%. Conclusion: Iliac crest autograft utilized for single or multilevel ACDF is associated with the highest fusion, lowest complication rates, and significantly lower costs compared with allograft, cages, PEEK, or other grafts. As spinal surgeons and institutions become more cost conscious, we will have to account for the “value added” of these increasingly expensive graft constructs. PMID:22905321

  14. Conjunctival autograft for pterygium

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    Clearfield, Elizabeth; Muthappan, Valliammai; Wang, Xue; Kuo, Irene C

    2016-01-01

    Background A pterygium is a fleshy, wing-shaped growth from the conjunctiva, crossing over the limbus onto the cornea. Prevalence ranges widely around the world. Evidence suggests that ultraviolet light is a major contributor in the formation of pterygia. Pterygia impair vision, limit eye movements, and can cause eye irritation, foreign body sensation, and dryness. In some susceptible patients, the pterygium can grow over the entire corneal surface, blocking the visual axis. Surgery is the only effective treatment for pterygium, though recurrences are common. With simple excision techniques (that is, excising the pterygium and leaving bare sclera), the risk of recurrence has been reported to be upwards of 80%. Pterygium excision combined with a tissue graft has a lower risk of recurrence. In conjunctival autograft surgery, conjunctival tissue from another part of the person’s eye along with limbal tissue is resected in one piece and used to cover the area from which the pterygium was excised. Another type of tissue graft surgery for pterygium is amniotic membrane graft, whereby a piece of donor amniotic membrane is fixed to the remaining limbus and bare sclera area after the pterygium has been excised. Objectives The objective of this review was to assess the safety and effectiveness of conjunctival autograft (with or without adjunctive therapy) compared with amniotic membrane graft (with or without adjunctive therapy) for pterygium. We also planned to determine whether use of MMC yielded better surgical results and to assess the direct and indirect comparative costs of these procedures. Search methods We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (Issue 10, 2015), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to November 2015), EMBASE (January 1980 to November 2015), PubMed (1948 to November 2015), Latin American and Caribbean Health Sciences Literature

  15. Soft tissue grafting to improve implant esthetics

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    Moawia M Kassab

    2010-09-01

    Full Text Available Moawia M KassabDivision of Periodontics, Marquette University, School of Dentistry, Milwaukee, WI, USAAbstract: Dental implants are becoming the treatment of choice to replace missing teeth, especially if the adjacent teeth are free of restorations. When minimal bone width is present, implant placement becomes a challenge and often resulting in recession and dehiscence around the implant that leads to subsequent gingival recession. To correct such defect, the author turned to soft tissue autografting and allografting to correct a buccal dehiscence around tooth #24 after a malpositioned implant placed by a different surgeon. A 25-year-old woman presented with the chief complaint of gingival recession and exposure of implant threads around tooth #24. The patient received three soft tissue grafting procedures to augment the gingival tissue. The first surgery included a connective tissue graft to increase the width of the keratinized gingival tissue. The second surgery included the use of autografting (connective tissue graft to coronally position the soft tissue and achieve implant coverage. The third and final surgery included the use of allografting material Alloderm to increase and mask the implant from showing through the gingiva. Healing period was uneventful for the patient. After three surgical procedures, it appears that soft tissue grafting has increased the width and height of the gingiva surrounding the implant. The accomplished thickness of gingival tissue appeared to mask the showing of implant threads through the gingival tissue and allowed for achieving the desired esthetic that the patient desired. The aim of the study is to present a clinical case with soft tissue grafting procedures.Keywords: case report, connective tissue, dental implants, allograft, coronally positioned flap

  16. Bone graft materials in fixation of orthopaedic implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan

    2013-01-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many...... orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include...... the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking...

  17. [Effectiveness of U-shape titanium screw-rod fixation system with bone autografting for lumbar spondylolysis of young adults].

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    Pu, Xiaobing; Yang, Shuangshi; Cao, Haiquan; Jing, Xingquan; Yin, Jun

    2014-03-01

    To investigate the effectiveness of U-shape titanium screw-rod fixation system with bone autografting for lumbar spondylolysis of young adults. Between January 2008 and December 2011, 32 patients with lumbar spondylolysis underwent U-shape titanium screw-rod fixation system with bone autografting. All patients were male with an average age of 22 years (range, 19-32 years). The disease duration ranged from 3 to 24 months (mean, 14 months). L3 was involved in spondylolysis in 2 cases, L4 in 10 cases, and L5 in 20 cases. The preoperative visual analogue scale (VAS) and Oswestry disability index (ODI) scores were 8.0 +/- 1.1 and 75.3 +/- 11.2, respectively. The operation time was 80-120 minutes (mean, 85 minutes), and the blood loss was 150-250 mL (mean, 210 mL). Primary healing of incision was obtained in all patients without complications of infection and nerve symptom. Thirty-two patients were followed up 12-24 months (mean, 14 months). Low back pain was significantly alleviated after operation. The VAS and ODI scores at 3 months after operation were 1.0 +/- 0.5 and 17.6 +/- 3.4, respectively, showing significant differences when compared with preoperative ones (t = 30.523, P = 0.000; t = 45.312, P = 0.000). X-ray films and CT showed bone fusion in the area of isthmus defects, with the bone fusion time of 6-12 months (mean, 9 months). During follow-up, no secondary lumbar spondyloly, adjacent segment degeneration, or loosening or breaking of internal fixator was found. The U-shape titanium screw-rod fixation system with bone autografting is a reliable treatment for lumbar spondylolysis of young adults because of a high fusion rate, minimal invasive, and maximum retention of lumbar range of motion.

  18. Quadriceps tendon autograft for arthroscopic knee ligament reconstruction: use it now, use it often.

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    Sheean, Andrew J; Musahl, Volker; Slone, Harris S; Xerogeanes, John W; Milinkovic, Danko; Fink, Christian; Hoser, Christian

    2018-04-28

    Traditional bone-patellar tendon-bone and hamstring tendon ACL grafts are not without limitations. A growing body of anatomic, biomechanical and clinical data has demonstrated the utility of quadriceps tendon autograft in arthroscopic knee ligament reconstruction. The quadriceps tendon autograft provides a robust volume of tissue that can be reliably harvested, mitigating the likelihood of variably sized grafts and obviating the necessity of allograft augmentation. Modern, minimally invasive harvest techniques offer the advantages of low rates of donor site morbidity and residual extensor mechanism strength deficits. New data suggest that quadriceps tendon autograft may possess superior biomechanical characteristics when compared with bone-patella tendon-bone (BPTB) autograft. However, there have been very few direct, prospective comparisons between the clinical outcomes associated with quadriceps tendon autograft and other autograft options (eg, hamstring tendon and bone-patellar tendon-bone). Nevertheless, quadriceps tendon autograft should be one of the primary options in any knee surgeon's armamentarium. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. Histological study on the new bone formation of the implanted bone allograft in sheep

    International Nuclear Information System (INIS)

    Li Youchen; Sun Guiying; Shi Zhancheng

    1999-01-01

    The purpose of this study is to compare the formation of new bone in the implanted frozen irradiated bone allograft with the fresh bone autograft. The work on animal model included resection and implantation of sheep's tibial diaphysis and intramedullary nail fixation, with total number 20. Tibias were harvested at 6, 12, and 24 months after operation. Sheep were fed with tetracycline I week before bone harvesting. Bones were examined with usual and fluorescence microscopes. The results showed that the progress of graft incorporation in allografts were generally similar to that of autografts. Capillaries penetration and callus formation extended from the host end to surround the host-graft junction in 6 months. Incorporation of new bone was nearly completed in 12 months; then the speed of new bone formation was decreased, and the implanted bone graft was almost completely substituted with non-nal bone structure in 24 months

  20. Autoinjerto conjuntival y membrana amniótica en la cirugía del pterigión primario Use of conjunctival autograft and amniotic membrane in primary pterygium surgery

    Directory of Open Access Journals (Sweden)

    Keyly Fernández García

    2012-12-01

    Full Text Available Objetivo: comparar la efectividad del autoinjerto conjuntival y el injerto de membrana amniótica en la cirugía del pterigión primario en el Instituto Cubano de Oftalmología "Ramón Pando Ferrer" de septiembre de 2009 a septiembre de 2010. Métodos: estudio prospectivo, comparativo y aleatorio. El universo estuvo constituido por 80 pacientes (80 ojos con diagnóstico de pterigión primario que se les realizó escisión quirúrgica de la hiperplasia fibrovascular nasal primaria. Se dividieron en 2 grupos al azar simple. Al grupo A (40 ojos se le implantó injerto de membrana amniótica y al grupo B (40 ojos autoinjerto de conjuntiva. Resultados: en seis meses de seguimiento se presentaron cuatro recurrencias (10 % en el grupo A y solo dos casos en el grupo B (5 %. En ninguno de los pacientes hubo complicación. Fue más efectivo el autoinjerto conjuntival. Conclusiones: la recidiva fue más frecuente en la cirugía con membrana amniótica aunque no existió una diferencia significativa. Se consideran ambas técnicas efectivas en esta afección.Objective: to compare the effectiveness of the conjunctival autograft and the amniotic membrane graft in the primary pterygium surgery at “Ramón Pando Ferrer” Cuban Institute of Ophthalmology from September 2009 to September 2010. Methods: a prospective, random and comparative study. The universe was composed by 80 eyes from 80 patients diagnosed with primary pterygium. They had undergone the surgical excision of a primary nasal fibrovascular hyperplasia. They were divided in two single-randomized groups (A and B; the group A patients (40 eyes were implanted with amniotic membrane graft whereas those of group B (40 eyes were implanted with conjunctival autograft. Results: during the 6 month follow-up, 4 recurrences were reported (10 % in group A and only 2 in group B (5 %. No complications were presented in both groups. The conjunctival autograft was more effective. Conclusions: the relapse was more

  1. Histological comparison of autograft, allograft-DBM, xenograft, and synthetic grafts in a trabecular bone defect: an experimental study in rabbits.

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    Athanasiou, Vasilis T; Papachristou, Dionysios J; Panagopoulos, Andreas; Saridis, Alkis; Scopa, Chrisoula D; Megas, Panagiotis

    2010-01-01

    Different types of bone-graft substitutes have been developed and are on the market worldwide to eliminate the drawbacks of autogenous grafting. This experimental animal study was undertaken to evaluate the different histological properties of various bone graft substitutes utilized in this hospital. Ninety New Zealand white rabbits were divided into six groups of 15 animals. Under general anesthesia, a 4.5 mm-wide hole was drilled into both the lateral femoral condyles of each rabbit, for a total of 180 condyles for analysis. The bone defects were filled with various grafts, these being 1) autograft, 2) DBM crunch allograft (Grafton), 3) bovine cancellous bone xenograft (Lubboc), 4) calcium phosphate hydroxyapatite substitute (Ceraform), 5) calcium sulfate substitute (Osteoset), and 6) no filling (control). The animals were sacrificed at 1, 3, and 6 months after implantation and tissue samples from the implanted areas were processed for histological evaluation. A histological grading scale was designed to determine the different histological parameters of bone healing. The highest histological grades were achieved with the use of cancellous bone autograft. Bovine xenograft (Lubboc) was the second best in the histological scale grading. The other substitutes (Grafton, Ceraform, Osteoset) had similar scores but were inferior to both allograft and xenograft. Bovine xenograft showed better biological response than the other bone graft substitutes; however, more clinical studies are necessary to determine its overall effectiveness.

  2. A comparison of revision and rerupture rates of ACL reconstruction between autografts and allografts in the skeletally immature.

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    Nelson, Ian R; Chen, Jason; Love, Rebecca; Davis, Brent R; Maletis, Gregory B; Funahashi, Tadashi T

    2016-03-01

    Anterior cruciate ligament reconstructions (ACLRs) in skeletally immature patients are increasing. The purpose of this study is to describe the demographics, graft usage, revision, and re-operation rates in skeletally immature ACLRs in the Kaiser Permanente healthcare system. Skeletally immature patients (type; bone-patellar-tendon-bone (BPTB) autograft, hamstring autograft, and any type of allograft. Age, gender, body mass index (BMI), and race were evaluated as confounders. Cox proportional hazard models stratified by surgeon were used to analyse the risk of revision and re-operation. A total of 534 primary ACLR cases were evaluated with a mean follow-up of 2.9 years. The majority were hamstring autografts (n = 388, 72.7%), male (n = 339, 63.9%), and White (n = 232, 43.4%). Median age was 14.9 years, and median BMI was 21.9 kg/m(2). There were 44 (8.2%) aseptic revisions and 48 (9.0%) same-knee re-operations. The incidence rate for revision was BPTB autograft 5.5%, hamstring autograft 7.5%, and allograft 13.2%. After adjusting for confounders and surgeon clustering effect, the risk of aseptic revision and revision between allograft and hamstring autograft did not reach statistical significance. Graft selection differs in skeletally immature patients with a preponderance of surgeries being performed with hamstring tendon autografts. High revision rates were identified for all graft types used, though differences in revision rates across different graft types did not reach statistical significance. Surgeons should be aware of high rates of revision in this skeletally immature young population, although type of graft used did not appear to make a difference. III.

  3. Can bone scintigraphy predict the final outcome of pasteurized autografts?

    International Nuclear Information System (INIS)

    Eid, Ahmed Shawky; Jeon, Dae-Geun; Cho, Wan Hyeong

    2010-01-01

    As pasteurization is becoming more widely used in limb salvage reconstruction, more study is required to understand about host-graft junction healing, graft revascularization and incorporation, and the incidence and type of complications among pasteurized autografts. This was mainly achieved by follow-up radiography. We aimed to clarify whether Tc99m bone scanning can be considered a reliable method in determining these three parameters. Twenty-seven osteosarcoma patients with pasteurized autograft reconstructions were retrospectively reviewed using available scintigraphic and radiographic follow-up every 6 months postoperatively for 36 months. Follow-up of the unhealed cases was continued for the maximum follow-up period available for each case beyond the original study period, ranging from 1 to 15 months. Tc99m uptake was classified as cold, faint, moderate and high uptake. Junction healing was classified as none, partial and complete healing. Seventy percent of junctions united with a mean of 22 months. Ninety to 100% of junctions showed increased uptake (high or moderate) at one time of the study regardless of final outcome. 85% of the pasteurized grafts showed the characteristic ''tramline appearance''. Four grafts (15%) were complicated: pseudoarthrosis and implant failure (1), fractured plate (1), intramedullary nail (IMN) fracture (1), and prosthesis stem loosening in the host bone (1), with underlying unhealed junctions in all cases. Bone scanning can determine the stages of the graft's rim revascularization and incorporation; however, it cannot detect or predict junction healing or occurrence of complications. Supplementary treatment of unhealed junctions showing either decreased junctional uptake or graft quiescence may be warranted. Otherwise, detection of distant metastasis and early local recurrence remains the main application of Tc99m scanning in the management of bone sarcomas. (orig.)

  4. Can bone scintigraphy predict the final outcome of pasteurized autografts?

    Energy Technology Data Exchange (ETDEWEB)

    Eid, Ahmed Shawky [Ain Shams University, Department of Orthopedic Surgery, Cairo (Egypt); Jeon, Dae-Geun; Cho, Wan Hyeong [Korea Cancer Center Hospital, Department of Orthopedic Surgery, Seoul (Korea)

    2010-10-15

    As pasteurization is becoming more widely used in limb salvage reconstruction, more study is required to understand about host-graft junction healing, graft revascularization and incorporation, and the incidence and type of complications among pasteurized autografts. This was mainly achieved by follow-up radiography. We aimed to clarify whether Tc99m bone scanning can be considered a reliable method in determining these three parameters. Twenty-seven osteosarcoma patients with pasteurized autograft reconstructions were retrospectively reviewed using available scintigraphic and radiographic follow-up every 6 months postoperatively for 36 months. Follow-up of the unhealed cases was continued for the maximum follow-up period available for each case beyond the original study period, ranging from 1 to 15 months. Tc99m uptake was classified as cold, faint, moderate and high uptake. Junction healing was classified as none, partial and complete healing. Seventy percent of junctions united with a mean of 22 months. Ninety to 100% of junctions showed increased uptake (high or moderate) at one time of the study regardless of final outcome. 85% of the pasteurized grafts showed the characteristic ''tramline appearance''. Four grafts (15%) were complicated: pseudoarthrosis and implant failure (1), fractured plate (1), intramedullary nail (IMN) fracture (1), and prosthesis stem loosening in the host bone (1), with underlying unhealed junctions in all cases. Bone scanning can determine the stages of the graft's rim revascularization and incorporation; however, it cannot detect or predict junction healing or occurrence of complications. Supplementary treatment of unhealed junctions showing either decreased junctional uptake or graft quiescence may be warranted. Otherwise, detection of distant metastasis and early local recurrence remains the main application of Tc99m scanning in the management of bone sarcomas. (orig.)

  5. Inferior limbal conjunctival autografting in primary pterygium

    Directory of Open Access Journals (Sweden)

    Farouk M Othman

    2015-01-01

    In patients with primary pterygium, conjunctival limbal autografting from the lower bulbar conjunctiva is an effective technique with a low recurrence rate. It can be a suitable treatment for glaucomatous patients with pterygium to leave the upper bulbar conjunctiva untouched.

  6. Two-stage implant systems.

    Science.gov (United States)

    Fritz, M E

    1999-06-01

    Since the advent of osseointegration approximately 20 years ago, there has been a great deal of scientific data developed on two-stage integrated implant systems. Although these implants were originally designed primarily for fixed prostheses in the mandibular arch, they have been used in partially dentate patients, in patients needing overdentures, and in single-tooth restorations. In addition, this implant system has been placed in extraction sites, in bone-grafted areas, and in maxillary sinus elevations. Often, the documentation of these procedures has lagged. In addition, most of the reports use survival criteria to describe results, often providing overly optimistic data. It can be said that the literature describes a true adhesion of the epithelium to the implant similar to adhesion to teeth, that two-stage implants appear to have direct contact somewhere between 50% and 70% of the implant surface, that the microbial flora of the two-stage implant system closely resembles that of the natural tooth, and that the microbiology of periodontitis appears to be closely related to peri-implantitis. In evaluations of the data from implant placement in all of the above-noted situations by means of meta-analysis, it appears that there is a strong case that two-stage dental implants are successful, usually showing a confidence interval of over 90%. It also appears that the mandibular implants are more successful than maxillary implants. Studies also show that overdenture therapy is valid, and that single-tooth implants and implants placed in partially dentate mouths have a success rate that is quite good, although not quite as high as in the fully edentulous dentition. It would also appear that the potential causes of failure in the two-stage dental implant systems are peri-implantitis, placement of implants in poor-quality bone, and improper loading of implants. There are now data addressing modifications of the implant surface to alter the percentage of

  7. Microsurgical head and neck tissue repair by visceral mini-autografting

    Directory of Open Access Journals (Sweden)

    A. D. Kaprin

    2015-01-01

    Full Text Available Objective. To minimize surgical trauma in patients with head and neck tumors during microsurgical plasty with visceral autografts.Subjects and methods. Clinical experience has been gained in the treatment of 53 patients with locally advanced craniofascial (n = 27 and oropharyngeal (n = 36 cancers. Abdominal organs were used for plastic closure of extensive defects after surgical resection. Paraumbilical incision allowing for an adequate approach into the abdominal cavity with minimal external trauma in the anterior abdominal wall was chosen as an access procedure. Video-assisted techniques were used to excise the midline aponeurosis. Donor organs, such as the omentum, greater curvature of the stomach, transverse colon, small intestine were taken through a mini-laparotomic incision to the anterior abdominal wall, then the vascular pedicle was exposed and a visceral autograft was made. After forming and cutting off the autograft, organ anastomoses were created extracorporeally.Results. Mini-access surgery could be completed in 50 of the 53 cases (4 patients had previously undergone abdominal interventions. Omental (n = 26, colo-omental (n = 15, gastro-omental (n = 7, and entero-omental (n = 5 flaps were made and prepared for autografting. No intra- or postoperative abdominal complications were found.Conclusion. Minimally invasive technologies used to create visceral authografts for head and neck tissue repair can minimize surgical trauma and reduce treatment duration. The indications for this access are the debilitating state of a cancer patient or the young age of a patient who does not wish to have an additional scar in the donor region.

  8. Accidental ovarian autograft after a laparoscopic surgery: case report.

    Science.gov (United States)

    Marconi, G; Quintana, R; Rueda-Leverone, N G; Vighi, S

    1997-08-01

    To report an autograft of ovarian tissue in the incision of the surgical trocar during laparoscopic surgery and to assess the potentiality of grafting of ovarian parenchyma in nonpelvic tissue in humans. A case report. Instituto de Fertilidad y Ginecología de Buenos Aires (IFER), Buenos Aires, Argentina. Infertile patient undergoing surgery due to an endometriotic cyst of the left ovary. Laparoscopic cystectomy. Accidental retention of a portion of the capsule and adjacent ovarian tissue of the endometrioma in SC cellular tissue. Months after surgery, a SC tumor was formed under the surgical incision. It was subsequently excised. Observation of tumor growth during menstrual cycles and ovulation induction; anatomopathologic study of the tissue after its extirpation. The tumor grew spontaneously in the periovulatory period and during treatments of ovulation induction. The anatomopathologic report of the tumor, removed 15 months after the first surgery, revealed functioning ovarian tissue with vessels of neoformation. This is the first description of autografted ovarian tissue in humans. We describe that the ovary can maintain its ovulatory function even in the absence of its pedicel. Also, we suggest that extirpation of surgical material through the incision of the trocar is not recommended, as the possibility of "sowing" or of autografts may occur.

  9. Outcome of pregnancy in women after pulmonary autograft valve replacement for congenital aortic valve disease

    NARCIS (Netherlands)

    Yap, Sing-Chien; Drenthen, Willem; Pieper, Petronella G.; Moons, Philip; Mulder, Barbara J. M.; Klieverik, Loes M.; Vliegen, Hubert W.; van Dijk, Arie P. J.; Meijboom, Folkert J.; Roos-Hesselink, Jolien W.

    Background and aim of the study: The pulmonary autograft has been recommended as the valve of choice for aortic valve replacement (AVR) in young women contemplating pregnancy. However, current information on maternal and perinatal outcome of pregnancy in women with pulmonary autograft valve

  10. Outcome of pregnancy in women after pulmonary autograft valve replacement for congenital aortic valve disease

    NARCIS (Netherlands)

    Yap, Sing-Chien; Drenthen, Willem; Pieper, Petronella G.; Moons, Philip; Mulder, Barbara J. M.; Klieverik, Loes M.; Vliegen, Hubert W.; van Dijk, Arie P. J.; Meijboom, Folkert J.; Roos-Hesselink, Jolien W.

    2007-01-01

    Background and aim of the study: The pulmonary autograft has been recommended as the valve of choice for aortic valve replacement (AVR) in young women contemplating pregnancy. However, current information on maternal and perinatal outcome of pregnancy in women with pulmonary autograft valve

  11. Outcome of pregnancy in women after pulmonary autograft valve replacement for congenital aortic valve disease.

    NARCIS (Netherlands)

    Yap, S.C.; Drenthen, W.; Pieper, P.G.; Moons, P.; Mulder, B.J.M.; Klieverik, L.M.; Vliegen, H.W.; Dijk, A.P.J. van; Meijboom, F.J.; Roos-Hesselink, J.W.

    2007-01-01

    BACKGROUND AND AIM OF THE STUDY: The pulmonary autograft has been recommended as the valve of choice for aortic valve replacement (AVR) in young women contemplating pregnancy. However, current information on maternal and perinatal outcome of pregnancy in women with pulmonary autograft valve

  12. One-stage Revision ACL reconstruction with hamstring autograft results in satisfactory outcome

    Science.gov (United States)

    Kejriwal, Ritwik; Buelow, Jens

    2017-01-01

    Objectives: Revision anterior cruciate ligament (ACL) reconstruction is associated with poorer outcomes and higher rerupture rates when compared to primary ACL reconstruction. There is also a significant heterogeneity in surgical technique, number of stages, and graft options. We report a large single surgeon case series with hamstring autograft as a graft option. Methods: Observational series of revision ACL reconstructions performed by the senior author between 2005 and 2015 was carried out. Chart reviews and clinic follow-ups were performed with the following recorded – re-rupture rate, radiographic grading of osteoarthritis, KT-1000 arthrometer test, IKDC outcome scores and knee range of motion. All patients underwent single bundle four-strand hamstring autograft performed in one stage with use of new tunnels in majority of the cases. Results: 66 patients underwent hamstring autograft one-stage revision ACL reconstruction by Dr Jens Buelow. Chart review was carried out on all patients, and 26 (39%) were followed up in clinic and/or by phone with a mean follow up of 4.7 years. Outcomes included re-rupture rate of 4.5%, reoperation rate of 12%, mean visual analogue scale score of 7.6, mean side-to-side difference of 2.6 mm for KT-1000 arthrometer test, and mean IKDC score of 79. Of the 17 patients with radiographs, 40% had moderate osteoarthritis (grade 2 or 3) at follow-up. Conclusion: Revision ACL reconstruction can result in a satisfactory outcome when performed with a hamstring autograft in one stage.

  13. Reducing Postoperative Pterygium Recurrence: Comparison of Free Conjunctival Auto-Graft and Conjunctival Rotation Flap Techniques

    International Nuclear Information System (INIS)

    Akhter, W.; Tayyab, A.; Kausar, A.; Masrur, A.

    2014-01-01

    Objective: To compare the recurrence of pterygium between free conjunctival auto-graft and conjunctival rotation flap following simple surgical excision of pterygium. Study Design: Quasi-experimental study. Place and Duration of Study: Shifa Foundation Community Health Clinic, Shifa College of Medicine, Islamabad, from January to November 2012. Methodology: Fifty seven cases aged above 18 years, with a pterygium corneal encroachment of 2 mm which was responsible for visual disability or was cosmetically undesirable were recruited for the study and randomly assigned to conjunctival auto-graft group and conjunctival rotation flap group. Cases with a history of glaucoma or glaucoma suspect, prior pterygium surgery, pterygium with concurrent ocular surface and lid disease, conjunctival inflammation and scarring, pseudo-pterygium or collagen vascular disease were excluded. After simple pterygium excision conjunctival auto-graft group (n=26) cases received a free conjunctival flap was transplanted, while conjunctival rotation flap group (n=31) cases received a conjunctival rotation flap. All cases were followed-up for 6 months after surgery for recurrence and complications. Frequency distribution and significance of association of recurrence using Fisher's exact test and Mann- Whitney U-test was carried out using Statistical Package for Social Sciences (SPSS) version 20. Results: The median (and inter-quartile range) age and surgery duration in conjunctival auto-graft group and conjunctival rotation flap group were 60 (51.50 - 63.00) and 57 (45.00 - 60.00) years, 28.50 (27.00 - 30.50) and 16.00 (15.00 - 17.00) minutes respectively. Recurrence was seen in 2 (7.96%) and 3 (9.76%) cases in auto-graft and rotation flap groups respectively. No significant difference was seen in postoperative complications between the two groups (p=0.60). Conclusion: The surgical time for conjunctival rotation flap procedure is less as compared to free auto-graft, while their recurrence and

  14. Implant retention systems for implant-retained overdentures.

    Science.gov (United States)

    Laverty, D P; Green, D; Marrison, D; Addy, L; Thomas, M B M

    2017-03-10

    Implant retained overdentures are being increasingly utilised in both general and specialist practice to rehabilitate patients with missing teeth, particularly those that are edentate. This article aims to inform the reader of a variety of retention systems that are available to retain an implant overdenture and to understand how these systems work, their advantages and disadvantages and to outline some of the clinical and treatment planning considerations involved in selecting the most appropriate retention system for patients.

  15. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    OpenAIRE

    Tejsu Malla; Jing Jiang; Kai Hu

    2018-01-01

    AIM: To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT), conjunctival autograft transplantation (CAT) alone and amniotic membrane transplantation (AMT) alone. METHODS: In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent) who underwent CAT (group A), AMT (group B) or CAT with AMT (group C) respectively follo...

  16. Precision of fit between implant impression coping and implant replica pairs for three implant systems.

    Science.gov (United States)

    Nicoll, Roxanna J; Sun, Albert; Haney, Stephan; Turkyilmaz, Ilser

    2013-01-01

    The fabrication of an accurately fitting implant-supported fixed prosthesis requires multiple steps, the first of which is assembling the impression coping on the implant. An imprecise fit of the impression coping on the implant will cause errors that will be magnified in subsequent steps of prosthesis fabrication. The purpose of this study was to characterize the 3-dimensional (3D) precision of fit between impression coping and implant replica pairs for 3 implant systems. The selected implant systems represent the 3 main joint types used in implant dentistry: external hexagonal, internal trilobe, and internal conical. Ten impression copings and 10 implant replicas from each of the 3 systems, B (Brånemark System), R (NobelReplace Select), and A (NobelActive) were paired. A standardized aluminum test body was luted to each impression coping, and the corresponding implant replica was embedded in a stone base. A coordinate measuring machine was used to quantify the maximum range of displacement in a vertical direction as a function of the tightening force applied to the guide pin. Maximum angular displacement in a horizontal plane was measured as a function of manual clockwise or counterclockwise rotation. Vertical and rotational positioning was analyzed by using 1-way analysis of variance (ANOVA). The Fisher protected least significant difference (PLSD) multiple comparisons test of the means was applied when the F-test in the ANOVA was significant (α=.05). The mean and standard deviation for change in the vertical positioning of impression copings was 4.3 ±2.1 μm for implant system B, 2.8 ±4.2 μm for implant system R, and 20.6 ±8.8 μm for implant system A. The mean and standard deviation for rotational positioning was 3.21 ±0.98 degrees for system B, 2.58 ±1.03 degrees for system R, and 5.30 ±0.79 degrees for system A. The P-value for vertical positioning between groups A and B and between groups A and R was <.001. No significant differences were found for

  17. Production of functional sperm by subcutaneous auto-grafting of immature testes in rainbow trout.

    Science.gov (United States)

    Hayashi, Makoto; Sakuma, Daika; Yoshizaki, Goro

    2018-02-01

    Sexually mature individuals are indispensable for breeding programs. Salmonids require a long period before reaching sexual maturity, so we aimed to shorten the period required to obtain functional sperm by grafting immature testicular fragments into mature recipients, which we predicted would allow the grafted testicular fragments to skip the long pre-pubertal period. First, we demonstrated successful subcutaneous auto-grafting of testicular fragments in rainbow trout. Unilateral testectomy was performed, and the isolated immature testicular fragment was auto-grafted into the subcutaneous space along the back of recipient fish. The grafted testicular fragments developed synchronously with the recipients' testis remaining in its body cavity, and both eventually produced functional sperm. Next, immature testicular fragments were auto-grafted into the subcutaneous space of sexually mature males. We achieved this, without immune rejection, by isolating and cryopreserving testes from immature fish, and rearing these unilaterally testectomized fish until sexual maturity. The cryopreserved testes were then auto-grafted into the original, now spermiating fish. The grated immature testicular fragments differentiated and produced functional sperm within 5 months after grafting. By combining this grafting method with a technique to avoid immune rejection, we expect to develop a practical method for producing sperm in a shorter period in salmonids. © 2017 Wiley Periodicals, Inc.

  18. A new system of implant abutment connection: how to improve a two piece implant system sealing.

    Science.gov (United States)

    Grecchi, F; DI Girolamo, M; Cura, F; Candotto, V; Carinci, F

    2017-01-01

    Implant dentistry has become one of the most successful dentistry techniques for replacing missing teeth. The success rate of implant dentistry is above 80%. However, peri-implantitis is a later complication of implant dentistry that if untreated, can lead to implant loss. One of the hypotized causes of peri-implantis is the bacterial leakage at the level of implant-abutment connection. Bacterial leakage is favored to the presence of a micro gap at the implant-abutment interface, allowing microorganisms to penetrate and colonize the inner part of the implant leading to biofilm accumulation and consequently to peri-implantitis development. To identify the capability of the implant to protect the internal space from the external environment, the passage of genetically modified Escherichia coli across implant-abutment interface was evaluated. Implants were immerged in a bacterial culture for twenty-four hours and then bacteria amount was measured inside implant-abutment interface with Real-time PCR. Bacteria were detected inside all studied implants, with a median percentage of 9%. The reported results are better to those of previous studies carried out on different implant systems. Until now, none implant-abutment system has been proven to seal the gap between implant and abutment.

  19. Pain level after ACL reconstruction: A comparative study between free quadriceps tendon and hamstring tendons autografts.

    Science.gov (United States)

    Buescu, Cristian Tudor; Onutu, Adela Hilda; Lucaciu, Dan Osvald; Todor, Adrian

    2017-03-01

    The objective of this study was to compare the pain levels and analgesic consumption after single bundle ACL reconstruction with free quadriceps tendon autograft versus hamstring tendon autograft. A total of 48 patients scheduled for anatomic single-bundle ACL reconstruction were randomized into two groups: the free quadriceps tendon autograft group (24 patients) and the hamstring tendons autograft group (24 patients). A basic multimodal analgesic postoperative program was used for all patients and rescue analgesia was provided with tramadol, at pain scores over 30 on the Visual Analog Scale. The time to the first rescue analgesic, the number of doses of tramadol and pain scores were recorded. The results within the same group were compared with the Wilcoxon signed test. Supplementary analgesic drug administration proved significantly higher in the group of subjects with hamstring grafts, with a median (interquartile range) of 1 (1.3) dose, compared to the group of subjects treated with a quadriceps graft, median = 0.5 (0.1.25) (p = 0.009). A significantly higher number of subjects with a quadriceps graft did not require any supplementary analgesic drug (50%) as compared with subjects with hamstring graft (13%; Z-statistics = 3.01, p = 0.002). The percentage of subjects who required a supplementary analgesic drug was 38% higher in the HT group compared with the FQT group. The use of the free quadriceps tendon autograft for ACL reconstruction leads to less pain and analgesic consumption in the immediate postoperative period compared with the use of hamstrings autograft. Level I Therapeutic study. Copyright © 2017 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  20. Results of a prospective randomized controlled trial of early ambulation for patients with lower extremity autografts.

    Science.gov (United States)

    Lorello, David John; Peck, Michael; Albrecht, Marlene; Richey, Karen J; Pressman, Melissa A

    2014-01-01

    It is common practice to keep those patients with lower extremity autografts immobile until post-operative day (POD) 5. There is however inherent risks associated with even short periods of immobility. As of now there are no randomized controlled trials looking at early ambulation of patients with lower extremity autografts in the burn community.The objective of this study was to show that patients who begin ambulation within 24 hours of lower extremity autografting will have no increased risk of graft failure than those patients who remain immobile until POD 5. Thirty-one subjects who received autografts to the lower extremity were randomized after surgery into either the early ambulation group (EAG;17 subjects) or the standard treatment group (STG;14 subjects). Those subjects randomized to the EAG began ambulating with physical therapy on POD 1. Subjects in the STG maintained bed rest until POD 5. There was no difference in the number of patients with graft loss in either the EAG or STG on POD 5, and during any of the follow-up visits. No subjects required regrafting. There was a significant difference in the mean minutes of ambulation, with the EAG ambulating longer than the STG (EAG 23.4 minutes [SD 12.03], STG 14.1 [SD 9.00], P=.0235) on POD 5. Burn patients with lower extremity autografts can safely ambulate on POD 1 without fear of graft failure compared with those patients that remain on bed rest for 5 days.

  1. Novel experimental surgical strategy to prevent traumatic neuroma formation by combining a 3D-printed Y-tube with an autograft.

    Science.gov (United States)

    Bolleboom, Anne; de Ruiter, Godard C W; Coert, J Henk; Tuk, Bastiaan; Holstege, Jan C; van Neck, Johan W

    2018-02-09

    OBJECTIVE Traumatic neuromas may develop after nerve injury at the proximal nerve stump, which can lead to neuropathic pain. These neuromas are often resistant to therapy, and excision of the neuroma frequently leads to recurrence. In this study, the authors present a novel surgical strategy to prevent neuroma formation based on the principle of centro-central anastomosis (CCA), but rather than directly connecting the nerve ends to an autograft, they created a loop using a 3D-printed polyethylene Y-shaped conduit with an autograft in the distal outlets. METHODS The 3D-printed Y-tube with autograft was investigated in a model of rat sciatic nerve transection in which the Y-tube was placed on the proximal sciatic nerve stump and a peroneal graft was placed between the distal outlets of the Y-tube to form a closed loop. This model was compared with a CCA model, in which a loop was created between the proximal tibial and peroneal nerves with a peroneal autograft. Additional control groups consisted of the closed Y-tube and the extended-arm Y-tube. Results were analyzed at 12 weeks of survival using nerve morphometry for the occurrence of neuroma formation and axonal regeneration in plastic semi-thin sections. RESULTS Among the different surgical groups, the Y-tube with interposed autograft was the only model that did not result in neuroma formation at 12 weeks of survival. In addition, a 13% reduction in the number of myelinated axons regenerating through the interposed autograft was observed in the Y-tube with autograft model. In the CCA model, the authors also observed a decrease of 17% in the number of myelinated axons, but neuroma formation was present in this model. The closed Y-tube resulted in minimal nerve regeneration inside the tube together with extensive neuroma formation before the entrance of the tube. The extended-arm Y-tube model clearly showed that the majority of the regenerating axons merged into the Y-tube arm, which was connected to the autograft

  2. MRI of anterior cruciate ligament repair with patellar and hamstring tendon autografts

    International Nuclear Information System (INIS)

    Jansson, K.A.; Karjalainen, P.T.; Harilainen, A.; Sandelin, J.; Tallroth, K.; Soila, K.; Aronen, H.J.

    2001-01-01

    Objective. Several MRI sequences were used to evaluate the 2-year postoperative appearance of asymptomatic knee with a torn anterior cruciate ligament (ACL) reconstructed with bone-patellar tendon-bone (BTB) and semitendinosus and gracilis (STG) tendon autografts.Design and patients. Two groups with successful repair of ACL tear with BTB (n=10) or STG (n=10) autografts were imaged at 1.5 T with sagittal and oblique coronal proton density-, T2-weighted and sagittal STIR sequences and plain and contrast-enhanced oblique coronal T1-weighted sequences. The appearance of the graft and periligamentous tissues was evaluated.Results. In all 20 cases, the ACL graft showed homogeneous, low signal intensity with periligamentous streaks of intermediate signal intensity on T2-weighted images. In 10 cases, localised areas of intermediate signal intensity were seen in the intra-articular segment of the graft on proton density- and T1-weighted images. The graft itself did not show enhancement in either of the two groups, but mild to moderate periligamentous enhancement was detected in 10 cases.Conclusion. The MRI appearance of ACL autograft is variable on proton density- and T1-weighted images. Periligamentous tissue showing contrast enhancement is a typical MRI finding after clinically successful ACL reconstruction. (orig.)

  3. The effects of bone marrow aspirate, bone graft, and collagen composites on fixation of titanium implants

    DEFF Research Database (Denmark)

    Babiker, Hassan; Ding, Ming; Sandri, Monica

    2012-01-01

    Replacement of extensive local bone loss especially in revision joint arthroplasty and spine fusion is a significant clinical challenge. Allograft and autograft have been considered as gold standards for bone replacement. However, there are several disadvantages such as donor site pain, bacterial...... contamination, and non union as well as the potential risk of disease transmission. Hydroxyapatite and collagen composites (HA/Collagen) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effects of newly developed HA/Collagen-composites with and without bone...... marrow aspirate (BMA) on enhancement of bone implant fixation. Method: Titanium alloy implants were inserted into bilateral femoral condyles of eight skeletally mature sheep, four implants per sheep. The implant had a circumferential gap of 2 mm. The gap was filled with: HA/Collagen; HA...

  4. Biceps Autograft Augmentation for Rotator Cuff Repair : A Systematic Review

    NARCIS (Netherlands)

    Veen, Egbert J D; Stevens, Martin; Diercks, Ronald L

    Purpose: To improve surgical outcomes in patients with massive cuff defects, different techniques and augmentations are proposed. The biceps tendon is easily available as an autograft. Our aim was to conduct a qualitative systematic review of various methods and surgical techniques that use a biceps

  5. Quadriceps Tendon Autograft in Anterior Cruciate Ligament Reconstruction: A Systematic Review.

    Science.gov (United States)

    Hurley, Eoghan T; Calvo-Gurry, Manuel; Withers, Dan; Farrington, Shane K; Moran, Ray; Moran, Cathal J

    2018-05-01

    To systematically review the current evidence to ascertain whether quadriceps tendon autograft (QT) is a viable option in anterior cruciate ligament reconstruction. A literature review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Cohort studies comparing QT with bone-patellar tendon-bone autograft (BPTB) or hamstring tendon autograft (HT) were included. Clinical outcomes were compared, with all statistical analyses performed using IBM SPSS Statistics for Windows, version 22.0, with P < .05 being considered statistically significant. We identified 15 clinical trials with 1,910 patients. In all included studies, QT resulted in lower rates of anterior knee pain than BPTB. There was no difference in the rate of graft rupture between QT and BPTB or HT in any of the studies reporting this. One study found that QT resulted in greater knee stability than BPTB, and another study found increased stability compared with HT. One study found that QT resulted in improved functional outcomes compared with BPTB, and another found improved outcomes compared with HT, but one study found worse outcomes compared with BPTB. Current literature suggests QT is a viable option in anterior cruciate ligament reconstruction, with published literature showing comparable knee stability, functional outcomes, donor-site morbidity, and rerupture rates compared with BPTB and HT. Level III, systematic review of Level I, II, and III studies. Copyright © 2018 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  6. Number and Quality of Oocytes Collected from Heterotopic Autografted Mice Ovary after PMSG Induction

    Directory of Open Access Journals (Sweden)

    NURBARIAH

    2011-12-01

    Full Text Available Heterotopic grafting sites can be useful in producing oocytes for in vitro Fertilization, therefore, maximising the oocyte yield from the graft by gonadotrophin stimulation would be advantageous. The aim of this study was to investigate the number and quality of oocytes collected from heterotopic autografted ovary after Pregnant Mare Serum Gonadothropin (PMSG induction. Graft recipients were treated either with or without PMSG stimulation 48 hours prior to graft collection. Ovarian tissue from four weeks old mice (DDY strain were autotransplanted under the kidney capsule of the same ovariectomized mice and the oocytes were collected 21 days after autotransplantation. The results showed that the average number of oocytes collected from autografted ovaries without PMSG induction were 9.0. ± 2.8 not significantly different with those received PMSG induction, 10.9 ± 5.1. The percentage of matured and fertilized oocytes and the developed embryos from the autografted ovaries without PMSG induction were 52.4, 33.4, and 26.0%, respectively not significantly different with those received PMSG induction, 53.2, 35.1, and 29.9%, respectively. The number of oocytes and the capacity to matured, fertilized and developed were significantly lower (P < 0.05 compared to the superovulated nongrafted (control ovaries. In conclusion, PMSG induction on the graft recipients did not significantly increase oocytes yield from grafted heterotopic ovaries. The number and quality of oocytes produced from the autografted ovaries were lower than the superovulated nongrafted ovaries, but still can be used for in vitro embryo production after sequential in vitro maturation and fertilization.

  7. Allograft versus autograft in cervical and lumbar spinal fusions: an examination of operative time, length of stay, surgical site infection, and blood transfusions.

    Science.gov (United States)

    Murphy, Meghan E; McCutcheon, Brandon A; Grauberger, Jennifer; Shepherd, Daniel; Maloney, Patrick R; Rinaldo, Lorenzo; Kerezoudis, Panagiotis; Fogelson, Jeremy L; Nassr, Ahmad; Bydon, Mohamad

    2016-11-23

    Autograft harvesting for spine arthrodesis has been associated with longer operative times and increased blood loss. Allograft compared to autograft in spinal fusions has not been studied in a multicenter cohort. Patients enrolled in the ACS-NSQIP registry between 2012 and 2013 who underwent cervical or lumbar spinal fusion with either allograft or autograft through a separate incision were included for analysis. The primary outcomes of interest were operative time, length of stay, blood transfusion, and surgical site infection (SSI). A total of 6,790 and 6,718 patients received a cervical or lumbar spinal fusion, respectively. On unadjusted analysis in both cervical and lumbar cohorts, autograft was associated with increased rates of blood transfusion (cervical: 2.9% vs 1.0%, poperative time (cervical: 167 vs 128 minutes, poperative times (cervical: 27.8 minutes, 95% CI 20.7-35.0; and lumbar: 25.4 minutes, 95% CI 17.7-33.1) relative to allograft. Autograft was not associated with either length of stay or SSI. In a multicenter cohort of patients undergoing cervical or lumbar spinal fusion, autograft was associated with increased rates of blood transfusion and increased operative time relative to allograft.

  8. Use of customized polyetheretherketone (PEEK) implants in the reconstruction of complex maxillofacial defects.

    Science.gov (United States)

    Kim, Michael M; Boahene, Kofi D O; Byrne, Patrick J

    2009-01-01

    Extensive maxillofacial defects resulting from trauma or oncologic resection present reconstructive challenges. Various autografts and alloplastic materials in conjunction with standard soft-tissue techniques have been used in the reconstruction of these types of defects. Polyetheretherketone (PEEK) is a semicrystalline polyaromatic linear polymer exhibiting an excellent combination of strength, stiffness, durability, and environmental resistance. Recent investigations of PEEK as a biomaterial resulted in the successful treatment of cervical disk disease. We describe a series of 4 patients whose defects were reconstructed using customized PEEK implants. All had excellent postoperative aesthetic and functional results without complications such as infections or extrusions. Because PEEK implants are customizable, easily workable, inert, and nonporous, they represent an ideal alloplastic material for maxillofacial reconstruction.

  9. Ion implantation control system

    International Nuclear Information System (INIS)

    Gault, R. B.; Keutzer, L. L.

    1985-01-01

    A control system is disclosed for an ion implantation system of the type in which the wafers to be implanted are mounted around the periphery of a disk which rotates and also moves in a radial direction relative to an ion beam to expose successive sections of each wafer to the radiation. The control system senses beam current which passes through one or more apertures in the disk and is collected by a Faraday cup. This current is integrated to obtain a measure of charge which is compared with a calculated value based upon the desired ion dosage and other parameters. The resultant controls the number of incremental steps the rotating disk moves radially to expose the adjacent sections of each wafer. This process is continued usually with two or more traverses until the entire surface of each wafer has been implanted with the proper ion dosage

  10. Use of fibrin glue in the management of recurrent pterygium by conjunctival autograft

    International Nuclear Information System (INIS)

    Virendra K. Malik; Sandeep Kumar

    2010-01-01

    To evaluate whether use of fibrin glue instead of sutures for the treatment of recurrent pterygium with conjunctival auto-graft (CAG) further decreases its recurrence. A prospective, clinical open trial of 50 eyes of 50 patients with recurrent pterygium, who were randomly assigned to either, pterygium excision and CAG with fibrin glue (Group 1) or with 6 interrupted sutures (Group 2), was carried out from January 2009 to July 2010 at the outpatient department of Subharti Medical College, Meerut, North India. Both groups had 25 patients each. The groups were compared with regards to the surgical time taken, development of recurrence, postoperative symptoms (irritation, watering, and redness), and complications. Recurrence was seen in one (4%) eye in group I, and 3 (12%) eyes in group II after 9-13 months of follow up. The difference between the 2 groups was not statistically significant. The surgical time was significantly reduced, and postoperative inflammation and complications were less in group I. Postoperative symptoms were significantly more in group II patients. While conjunctival autograft with sutures for management of recurrent pterygium appears to be a safe and feasible modality, fibrin glue fixation of the autograft is a more viable option in terms of surgical ease, less time consuming, less postoperative complications, and less recurrence (Author).

  11. Long-term results of bone-retinaculum-bone autograft for scapholunate instability.

    Science.gov (United States)

    Soong, Maximillian; Merrell, Gregory A; Ortmann, Fred; Weiss, Arnold-Peter C

    2013-03-01

    To report long-term follow-up of scapholunate interosseous ligament reconstruction with bone-retinaculum-bone autograft in patients with dynamic scapholunate instability. Of the 14 patients from the previously reported cohort who had bone-retinaculum-bone autograft for dynamic instability, 6 returned for clinical examination and radiographs, 3 were reached by telephone, and 2 were lost to follow-up. The remaining 3 had salvage procedures (2 total wrist arthrodeses and 1 proximal row carpectomy) between the prior report and the current study and thus reached an endpoint, at 2 to 4 years. For the 6 who returned, outcome measurements included scapholunate angle and gap, radiographic evidence of secondary arthritis, wrist extension and flexion, grip strength, and Mayo wrist score. Follow-up averaged 11.9 years (range, 10.7-14.1 y). Clinical and radiographic outcomes deteriorated moderately from the prior report. Mayo wrist score averaged 83. There were 3 failures, resulting in 1 proximal row carpectomy and 2 total wrist arthrodeses. Findings at repeat surgery in the failed group included an intact graft without any apparent abnormalities, a partially ruptured graft (after a subsequent re-injury), and a completely resorbed graft. Bone-retinaculum-bone autograft reconstruction is a viable treatment option for dynamic scapholunate instability in which the scaphoid and lunate can be reduced. Results may deteriorate but are similar to those reported previously from other techniques. Problems with graft strength or stiffness may necessitate further surgery. Copyright © 2013 American Society for Surgery of the Hand. Published by Elsevier Inc. All rights reserved.

  12. Mandibular implant-supported overdentures: attachment systems, and number and locations of implants--Part I.

    Science.gov (United States)

    Warreth, Abdulhadi; Alkadhimi, Aslam Fadel; Sultan, Ahmed; Byrne, Caroline; Woods, Edel

    2015-01-01

    The use of dental implants in replacing missing teeth is an integral part of restorative dental treatment. Use of conventional complete dentures is associated with several problems such as lack of denture stability, support and retention. However, when mandibular complete dentures were used with two or more implants, an improvement in the patients' psychological and social well-being could be seen. There is general consensus that removable implant-supported overdentures (RISOs) with two implants should be considered as the first-choice standard of care for an edentulous mandible. This treatment option necessitates the use of attachment systems that connect the complete denture to the implant. Nevertheless, each attachment system has its inherent advantages and disadvantages, which should be considered when choosing a system. The first part of this article provides an overview on options available to restore the mandibular edentulous arch with dental implants. Different types of attachment systems, their features and drawbacks are also reviewed.

  13. CLINICAL CONSIDERATIONS OF DENTAL IMPLANT SYSTEM IN IMMEDIATE LOADING IMPLANT CASES

    Directory of Open Access Journals (Sweden)

    Carolina Damayanti Marpaung

    2015-06-01

    Full Text Available Immediate loading of dental implant has been researched intensively in the development of Branemark’s early concept of 2 stages implant placement. This was embarked from both patients and practiitioner’s convenience towards a simpler protocol and shorter time frame. Many recent researchers later found that micromotions derived from occlusal loading for a certain degree, instead of resulting a fibrous tissue encapsulation, can enhance the osseointegration process. Dental Implant system enhancement towards maximizing the primary stability held a key factor in Branemark’s concept development. Surgical protocol and implant design was found to give a significant contribution to the prognosis of immediate-loading implants.

  14. Implant angulation: 2-year retrospective analysis on the influence of dental implant angle insertion on marginal bone resorption in maxillary and mandibular osseous onlay grafts.

    Science.gov (United States)

    Ramaglia, Luca; Toti, Paolo; Sbordone, Carolina; Guidetti, Franco; Martuscelli, Ranieri; Sbordone, Ludovico

    2015-05-01

    The purpose of this study was to determine the existence of correlations between marginal peri-implant linear bone loss and the angulation of implants in maxillary and mandibular augmented areas over the course of a 2-year survey. Dependent variables described the sample of the present retrospective chart review. By using three-dimensional radiographs, input variables, describing the implant angulation (buccal-lingual angle [φ] and mesial-distal angle [θ]) were measured; outcome variables described survival rate and marginal bone resorption (MBR) around dental implants in autogenous grafts (10 maxillae and 14 mandibles). Pairwise comparisons and linear correlation coefficient were computed. The peri-implant MBR in maxillary buccal and palatal areas appeared less intensive in the presence of an increased angulation of an implant towards the palatal side. Minor MBR was recorded around mandibular dental implants positioned at a right angle and slightly angulated towards the mesial. Resorption in buccal areas may be less intensive as the angulation of placed implants increases towards the palatal area in the maxilla, whereas for the mandible, a greater inclination towards the lingual area could be negative. In the mandibular group, when the implant was slightly angulated in the direction of the distal area, bone resorption seemed to be more marked in the buccal area. In the planning of dental implant placement in reconstructed alveolar bone with autograft, the extremely unfavourable resorption at the buccal aspect should be considered; this marginal bone loss seemed to be very sensitive to the angulation of the dental implant.

  15. Biomechanical evaluation of tibial bone adaptation after revision total knee arthroplasty: A comparison of different implant systems.

    Directory of Open Access Journals (Sweden)

    María Paz Quilez

    Full Text Available The best methods to manage tibial bone defects following total knee arthroplasty remain under debate. Different fixation systems exist to help surgeons reconstruct knee osseous bone loss (such as tantalum cones, cement, modular metal augments, autografts, allografts and porous metaphyseal sleeves However, the effects of the various solutions on the long-term outcome remain unknown. In the present work, a bone remodeling mathematical model was used to predict bone remodeling after total knee arthroplasty (TKA revision. Five different types of prostheses were analyzed: one with a straight stem; two with offset stems, with and without supplements; and two with sleeves, with and without stems. Alterations in tibia bone density distribution and implant Von Mises stresses were quantified. In all cases, the bone density decreased in the proximal epiphysis and medullary channels, and an increase in bone density was predicted in the diaphysis and around stem tips. The highest bone resorption was predicted for the offset prosthesis without the supplement, and the highest bone formation was computed for the straight stem. The highest Von Mises stress was obtained for the straight tibial stem, and the lowest was observed for the stemless metaphyseal sleeves prosthesis. The computational model predicted different behaviors among the five systems. We were able to demonstrate the importance of choosing an adequate revision system and that in silico models may help surgeons choose patient-specific treatments.

  16. Randomized prospective study comparing tri-cortical iliac crest autograft to allograft in the lateral column lengthening component for operative correction of adult acquired flatfoot deformity.

    Science.gov (United States)

    Dolan, Christopher M; Henning, Jeffrey A; Anderson, John G; Bohay, Donald R; Kornmesser, Marc J; Endres, Terrence J

    2007-01-01

    Operative treatment of stage II posterior tibial tendon insufficiency (PTTI) is controversial. Many soft-tissue and bony procedures and various combinations of the two have been reported for treatment of stage II PTTI. Orthopaedists recognize the lateral column lengthening component of the procedure as a successful reconstructive technique. The use of cortical allograft for lateral column lengthening in the correction of pes planus in the pediatric patient population has been routine. In the adult population, however, tricortical iliac crest autograft has been the bone graft of choice. Harvest of this autograft can precipitate significant morbidity and cost. Therefore, we undertook this randomized controlled trial to compare graft incorporation and healing of allograft and autograft in the lateral column lengthening component of adult flatfoot reconstruction. Lateral column lengthening was done as a component of operative correction for stage II PTTI in adult patients (older than 18 years) by two surgeons using similar procedures. The patients were randomized to either the allograft or autograft procedures. The primary endpoint was graft incorporation and healing as assessed by radiographs. The study included 33 randomized feet in 31 patients. We followed 18 feet in the allograft group and 15 in the autograft group to the point of union. There were 21 women and 10 men. There were no delayed unions, nonunions, or hardware failures. All patients in both groups achieved bony union by the 12-week followup evaluation. Two superficial foot infections were successfully treated with oral antibiotics. Two patients in the autograft group continued to have hip donor site pain at 3 months. This study suggests that union rates of allograft and autograft (iliac crest bone graft) are equal. The use of allograft in the lateral column lengthening component of operative correction of adult stage II PTTI appears to be a viable alternative to the use of iliac crest autograft and

  17. The Effect of Iliac Crest Autograft on the Outcome of Fusion in the Setting of Degenerative Spondylolisthesis

    Science.gov (United States)

    Radcliff, Kristen; Hwang, Raymond; Hilibrand, Alan; Smith, Harvey E.; Gruskay, Jordan; Lurie, Jon D.; Zhao, Wenyan; Albert, Todd; Weinstein, James

    2012-01-01

    Background: There is considerable controversy about the long-term morbidity associated with the use of posterior autologous iliac crest bone graft for lumbar spine fusion procedures compared with the use of bone-graft substitutes. The hypothesis of this study was that there is no long-term difference in outcome for patients who had posterior lumbar fusion with or without iliac crest autograft. Methods: The study population includes patients enrolled in the degenerative spondylolisthesis cohort of the Spine Patient Outcomes Research Trial who underwent lumbar spinal fusion. Patients were divided according to whether they had or had not received posterior autologous iliac crest bone graft. Results: There were 108 patients who had fusion with iliac crest autograft and 246 who had fusion without iliac crest autograft. There were no baseline differences between groups in demographic characteristics, comorbidities, or baseline clinical scores. At baseline, the group that received iliac crest bone graft had an increased percentage of patients who had multilevel fusions (32% versus 21%; p = 0.033) and L5-S1 surgery (37% versus 26%; p = 0.031) compared with the group without iliac crest autograft. Operative time was higher in the iliac crest bone-graft group (233.4 versus 200.9 minutes; p case-by-case basis for lumbar spinal fusion. Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence. PMID:22878599

  18. Repair of sheep long bone cortical defects filled with COLLOSS, COLLOSS E, OSSAPLAST, and fresh iliac crest autograft.

    Science.gov (United States)

    Huffer, William E; Benedict, James J; Turner, A S; Briest, Arne; Rettenmaier, Robert; Springer, Marco; Walboomers, X F

    2007-08-01

    COLLOSS and COLLOSS E are osteoinductive bone void fillers consisting of bone collagen and noncollagenous proteins from bovine and equine bone, respectively. The aim of this study was to compare COLLOSS, COLLOSS E, iliac bone autograft, sintered beta tricalcium phosphate (beta-TCP; OSSAPLAST), and COLLOSS E plus OSSAPLAST. Materials were placed for 4, 8, or 24 weeks in 5-mm cortical bone defects in sheep long bones. Histological sections in a plane perpendicular to the long axis of the bone were used to measure the total repair area (original defect plus callus) and the area of bone within the total repair area. The incidence of defect union was also evaluated. At 4 and 8 weeks, defects treated with COLLOSS and COLLOSS E with or without OSSAPLAST had total repair and bone areas equivalent to autograft, and larger than OSSAPLAST-treated defects. At 8 weeks, the incidence of defect union was higher in defects treated with autograft or COLLOSS E plus OSSAPLAST than in untreated defects. At 24 weeks, the incidence of union was 100% in all treatment groups and 0% in untreated defects. The incidence of union was related to the degree of remodeling between 8 and 24 weeks. This was greater in all treated than nontreated defects. In conclusion, COLLOSS and COLLOSS E were equivalent to each other and to autograft, and superior to beta-TCP, in this study model.

  19. In vivo performance of combinations of autograft, demineralized bone matrix, and tricalcium phosphate in a rabbit femoral defect model

    International Nuclear Information System (INIS)

    Kim, Jinku; McBride, Sean; Hollinger, Jeffrey O; Dean, David D; Sylvia, Victor L; Doll, Bruce A

    2014-01-01

    Large bone defects may be treated with autologous or allogeneic bone preparations. Each treatment has advantages and disadvantages; therefore, a clinically viable option for treating large (e.g., gap) bone defects may be a combination of the two. In the present study, bone repair was determined with combinations of autografts, allografts, and synthetic bone grafts using an established rabbit femoral defect model. Bilateral unicortical femoral defects were surgically prepared and treated with combinatorial bone grafts according to one of seven treatment groups. Recipient sites were retrieved at six weeks. Cellular/tissue responses and new bone formation were assessed by histology and histomorphometry. Histological analysis images indicated neither evidence of inflammatory, immune responses, tissue necrosis, nor osteolysis. Data suggested co-integration of implanted agents with host and newly formed bone. Finally, the histomorphometric data suggested that the tricalcium phosphate-based synthetic bone graft substitute allowed new bone formation that was similar to the allograft (i.e., demineralized bone matrix, DBM). (paper)

  20. The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants in sheep

    DEFF Research Database (Denmark)

    Babiker, Hassan

      The effect of Hydroxyapatite/collagen I composites, bone marrow aspirate and bone graft on fixation of bone implants IN SHEEP   Ph.D. Student, Hassan Babiker; Associate Professor, Ph.D. Ming Ding; Professor, dr.med., Soren Overgaard. Department of Orthopaedic Surgery, Odense University Hospital......, Odense, Denmark   Background: Hydroxyapatite and collagen composites (HA/coll) have the potential in mimicking and replacing skeletal bones. This study attempted to determine the effect of newly developed HA/coll-composites with and without bone marrow aspirate (BMA) in order to enhance the fixation...... of bone implants.   Materials and Methods: Titanium alloy implants were inserted into bilateral femoral condyles of 8 skeletally mature sheep, four in each sheep. The implant has a circumferential gap of 2 mm. The gap was filled with: HA/coll; HA/coll-BMA; autograft or allograft. Allograft was served...

  1. Cranial implant design using augmented reality immersive system.

    Science.gov (United States)

    Ai, Zhuming; Evenhouse, Ray; Leigh, Jason; Charbel, Fady; Rasmussen, Mary

    2007-01-01

    Software tools that utilize haptics for sculpting precise fitting cranial implants are utilized in an augmented reality immersive system to create a virtual working environment for the modelers. The virtual environment is designed to mimic the traditional working environment as closely as possible, providing more functionality for the users. The implant design process uses patient CT data of a defective area. This volumetric data is displayed in an implant modeling tele-immersive augmented reality system where the modeler can build a patient specific implant that precisely fits the defect. To mimic the traditional sculpting workspace, the implant modeling augmented reality system includes stereo vision, viewer centered perspective, sense of touch, and collaboration. To achieve optimized performance, this system includes a dual-processor PC, fast volume rendering with three-dimensional texture mapping, the fast haptic rendering algorithm, and a multi-threading architecture. The system replaces the expensive and time consuming traditional sculpting steps such as physical sculpting, mold making, and defect stereolithography. This augmented reality system is part of a comprehensive tele-immersive system that includes a conference-room-sized system for tele-immersive small group consultation and an inexpensive, easily deployable networked desktop virtual reality system for surgical consultation, evaluation and collaboration. This system has been used to design patient-specific cranial implants with precise fit.

  2. Proximal hamstring reconstruction using semitendinosus and gracilis autograft: a novel technique.

    Science.gov (United States)

    Muellner, Thomas; Kumar, Sandeep; Singla, Amit

    2017-01-01

    The complete proximal hamstring avulsion is relatively uncommon injury and predominantly occurs in young athletes but causes significant functional impairment. In chronic cases, the muscle mass is so much retracted that primary repair is not possible. A surgical technique for reconstruction of chronic proximal hamstring avulsion using contralateral semitendinosus and gracilis autograft is described in this case report. V.

  3. A clinical case of single-stage correction of penetration combined orofacial defect with two microsurgical autografts

    Directory of Open Access Journals (Sweden)

    A. D. Kaprin

    2015-01-01

    Full Text Available After surgical treatment for locally advanced oral tumors with resection of soft tissues, mucosal membrane, and facial skeletal structures, there are penetration combined defects, removal of which is a challenge for reconstructive surgeons. Mandibular repair is one of the problems in the correction of combined oral defects. Surgeons use different grafts to remove mandibular defects. One-flap transplantation does not always solve all reconstruction problems and ensure the repair of the mucosal membrane, a soft-tissue component, skin integuments, and facial skeleton.The authors describe a clinical case of successful single-stage correction of penetration combined orofacial defect after resection of the tongue, mouth floor, en bloc resection of the lower jaw and mental soft tissues, bilateral cervical supramyochoroidal lymphadenectomy, stage LCL CM mandibular defect formation after J. Boyd, by using two microsurgical autografts (a peroneal skin-muscle-skin autograft and a radial skin-fascia one in a 39-year-old female patient clinically diagnosed with carcinoma of the left mandibular alveolar ridge mucosa, Stage IVA (T4аN0M0.The Department of Microsurgery, P.A. Herzen Moscow Oncology Research Institute, Ministry of Health of Russia, has gained experience in comprehensively correcting extensive combined maxillofacial defects with two or more grafts in 27 patients who underwent autografting with a total of 73 flaps. The most functionally incapacitating and life-incompatible defect was removed at Stage 1 of reconstructive treatment. Delayed reconstruction was made after a complex of specialized antitumor therapy and assessment of treatment results in the absence of progressive growth. A great problem during multi-stage defect correction is presented by the lack of recipient vessels after cervical lymphadenectomy, the presence of soft tissue scar changes, trismus, temporomandibular joint ankylosis, contractures and displacement of the edges of the

  4. Combined Conjunctival Autograft and Overlay Amniotic Membrane Transplantation; a Novel Surgical Treatment for Pterygium

    Directory of Open Access Journals (Sweden)

    Siamak Zarei Ghanavati

    2014-01-01

    Full Text Available The authors report the long-term results of combined conjunctival autograft and overlay amniotic membrane transplantation (AMT for treatment of pterygium as a new surgical technique. Nineteen patients including 12 male and 7 female subjects with pterygium (primary, 14 cases; recurrent, 5 cases underwent combined conjunctival autograft and overlay AMT and were followed from 10 to 26 months. Mean age was 44.21±12.49 (range, 29.0-73.0 years. In one patient with grade T3 primary pterygium, the lesion recurred (5.2%, recurrence rate. No intra-and postoperative complication developed. This procedure seems a safe and effective surgical technique for pterygium treatment. Protection of the ocular surface during the early postoperative period reduces the friction-induced inflammation and might be helpful to prevent the recurrence.

  5. Remote powering and data communication for implanted biomedical systems

    CERN Document Server

    Kilinc, Enver Gurhan; Maloberti, Franco

    2016-01-01

    This book describes new circuits and systems for implantable biomedical applications and explains the design of a batteryless, remotely-powered implantable micro-system, designed for long-term patient monitoring.  Following new trends in implantable biomedical applications, the authors demonstrate a system which is capable of efficient, remote powering and reliable data communication.  Novel architecture and design methodologies are used to transfer power with a low-power, optimized inductive link and data is transmitted by a reliable communication link.  Additionally, an electro-mechanical solution is presented for tracking and monitoring the implantable system, while the patient is mobile.  ·         Describes practical example of an implantable batteryless biomedical system; ·         Analyzes and compares various energy harvesting and power transfer methods; ·         Describes design of remote powering link and data communication of the implantable system, comparing differe...

  6. Hip Implant Systems

    Science.gov (United States)

    ... Implants and Prosthetics Metal-on-Metal Hip Implants Hip Implants Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Hip implants are medical devices intended to restore mobility ...

  7. Implant Angle Monitor System of MC3-II

    International Nuclear Information System (INIS)

    Sato, Fumiaki; Sano, Makoto; Nakaoka, Hiroaki; Fujii, Yoshito; Kudo, Tetuya; Nakanishi, Makoto; Koike, Masazumi; Fujino, Yasushi

    2008-01-01

    Precise implant angle control is required for the latest generation of ion implanters to meet further shrink semiconductor device requirements. Especially, the highest angle accuracy is required for Halo implant process of Logic devices. The Halo implant angle affects the device performance, because slight differences of beam divergence change the overlap profile towards the extension. Additionally, twist angle accuracy is demanded in case of channeling angle implant. Therefore monitoring beam angles and wafer twist angles is important. A new monitoring system for the MC3-II, SEN Corp.'s single wafer type medium current implanter has been developed. This paper describes the angle control performance and monitoring system of the MC3-II. For the twist angle control, we developed a wafer notch angle monitor. The system monitors the wafer notch image on the platen. And the notch angle variation is calculated by using image processing method. It is also able to adjust the notch angle according to the angle error. For the tilt angle control, we developed a vertical beam profile monitor. The monitor system can detect beam profile of vertical directions with horizontally scanning beam. It also measures beam angles of a tilt direction to a wafer. The system configuration and sample beam data are presented.

  8. Cone-morse implant connection system significantly reduces bacterial leakage between implant and abutment: an in vitro study.

    Science.gov (United States)

    Baj, A; Bolzoni, A; Russillo, A; Lauritano, D; Palmieri, A; Cura, F; Silvestre, F J; Giannì, A B

    2017-01-01

    Osseointegrated implants are very popular dental treatments today in the world. In osseointegrated implants, the occlusal forces are transmitted from prosthesis through an abutment to a dental implant. The abutment is connected to the implant by mean of a screw. A screw is the most used mean for connecting an implant to an abutment. Frequently the screws break and are lost. There is an alternative to screw retained abutment systems: the cone-morse connection (CMC). The CMC, thanks to the absence of the abutment screw, guarantees no micro-gaps, no micro-movements, and a reduction of bacterial leakage between implant and abutment. As P. gingivalis and T. forsythia penetration might have clinical relevance, it was the purpose of this investigation to evaluate molecular leakage of these two bacteria in a new CMC implants systems (Leone Spa®, Florence, Italy). To identify the capability of the implant to protect the internal space from the external environment, the passage of genetically modified Escherichia coli across implant-abutment interface was evaluated. Four cone-morse Leone implants (Leone® Spa, Florence, Italy) were immerged in a bacterial culture for 24 h and bacteria amount was then measured inside implant-abutment interface with Real-time PCR. Bacteria were detected inside all studied implants, with a median percentage of 3% for P. gingivalis and 4% for T. forsythia. Cone-morse connection implant system has very low bacterial leakage percentage and is similar to one-piece implants.

  9. Image-guided navigation system for placing dental implants.

    Science.gov (United States)

    Casap, Nardy; Wexler, Alon; Lustmann, Joshua

    2004-10-01

    Navigation-guided surgery has recently been introduced into various surgical disciplines, including oral and maxillofacial surgery. Since the advent of dental implants, dental computed tomography (CT) scans have been used as a diagnostic tool for preoperative planning, but not as part of the surgical phase. This article explains the principles of computer-assisted surgery and describes the use of a computer-guided navigation system in dental implantology. The system uses preoperative dental CT scans for planning and as an integral part of the surgical procedure. This system allows continuous intraoperative coordination of the implantation phase with the preoperative plan, optimizing the accuracy of implant surgery. Deviations from the planned location of the implants are minimal. Several cases are discussed.

  10. Soft tissue management for dental implants: what are the most effective techniques? A Cochrane systematic review.

    Science.gov (United States)

    Esposito, Marco; Maghaireh, Hassan; Grusovin, Maria Gabriella; Ziounas, Ioannis; Worthington, Helen V

    2012-01-01

    using risk ratios for dichotomous outcomes and mean differences for continuous outcomes with 95% confidence intervals (CI). Seventeen potentially eligible RCTs were identified but only six trials with 138 patients in total could be included. The following techniques were compared in the six included studies: flapless placement of dental implants versus conventional flap elevation (2 trials, 56 patients), crestal versus vestibular incisions (1 trial, 10 patients), Erbium:YAG laser versus flap elevation at the second-stage surgery for implant exposure (1 trial, 20 patients), whether a connective tissue graft at implant placement could be effective in augmenting peri-implant tissues (1 split-mouth trial, 10 patients), and autograft versus an animal-derived collagen matrix to increase the height of the keratinised mucosa (1 trial, 40 patients). On a patient rather than per implant basis, implants placed with a flapless technique and implant exposures performed with laser lead to statistically significantly less postoperative pain than flap elevation. Sites augmented with soft tissue connective grafts had better aesthetics and thicker tissues. Both palatal autografts or the use of a porcine-derived collagen matrix are effective in increasing the height of keratinised mucosa at the cost of a 0.5 mm recession of peri-implant soft tissues. There were no other statistically significant differences for any of the remaining analyses. There is limited weak evidence suggesting that flapless implant placement is feasible and has been shown to reduce patient postoperative discomfort in adequately selected patients, that augmentation at implant sites with soft tissue grafts is effective in increasing soft tissue thickness and improving aesthetics, and that one technique to increase the height of keratinised mucosa using autografts or an animal-derived collagen matrix was able to achieve its goal but at the cost of a worsened aesthetic outcome (0.5 mm of recession). There is

  11. Alternatives to Autograft Evaluated in a Rabbit Segmental Bone Defect

    Science.gov (United States)

    2015-07-09

    mesenchymal stem cells for off-the-shelf bone tissue engineering application. Biomaterials 33(9):2656–2672. doi:10.1016/j.biomaterials.2011.12.025 14...segmental bone defects in the rabbit with vascularized tissue engineered bone . Biomaterials 31(6):1171– 1179. doi:10.1016/j.biomaterials.2009.10.043 International Orthopaedics (SICOT) ...ORIGINAL PAPER Alternatives to autograft evaluated in a rabbit segmental bone defect Jennifer S. McDaniel1 & Marcello Pilia1 & Vivek Raut2 & Jeffrey

  12. Management of a Congenitally Missing Lateral Incisor with Orthodontics, Bone Grafting (a New Method and Single-Tooth Implant: A Case Report

    Directory of Open Access Journals (Sweden)

    Hamid Reza Arab

    2014-03-01

    Full Text Available Careful treatment planning, space management, augmentation of bone and attention to the details of implant surgical and prosthetic techniques are important factors when treating anterior maxilla specially replacement of missing teeth. This case report addresses a chair-side ridge augmentation procedure using autograft bone harvested with trephine drills and placed without using screws and the fundamental considerations related to replacement of a congenitally missing lateral incisor by a team approach

  13. Patient satisfaction with maxillary 3-implant overdentures using different attachment systems opposing mandibular 2-implant overdentures.

    Science.gov (United States)

    Al-Zubeidi, Mohammed I; Alsabeeha, Nabeel H M; Thomson, W Murray; Payne, Alan G T

    2012-05-01

    Patient-based outcomes with maxillary overdentures on a minimum number of implants, opposing mandibular 2-implant overdentures are not evident in the literature. To evaluate patient's satisfaction with maxillary 3-implant overdentures, opposing mandibular 2-implant overdentures, using two different attachment systems over the first 2 years of service. Forty participants wearing mandibular 2-implant overdentures for 3 years were randomly allocated to one of two similar implant system groups to receive maxillary 3-implant overdentures. Twenty participants were allocated to splinted and unsplinted attachment system treatment groups for each system. Patient satisfaction with pre-treatment complete maxillary dentures, with maxillary 3-implant overdentures at baseline and annually for 2 years, was measured using visual analogue scale questionnaires and the oral health impact profiles. Palatal coverage of the maxillary overdentures was reduced at the first annual recall. Data showed significant improvement in pain reduction, comfort, stability, and function variables of the visual analogue scale after treatment. Analysis by prosthodontic design using visual analogue scale showed no significant difference. The total oral health impact profile-14 scores after treatment for all participants, regardless of prosthodontic design, were significantly lower (more satisfied). The overall oral health impact profile-20E score at baseline was significantly higher (more satisfied) compared with pre-treatment conventional maxillary dentures. No significant changes were observed in the first or second years compared with baseline results. Twenty-two participants (84.6%) preferred reduced palatal coverage, regardless of prosthodontic design, after 1 year. Twenty participants (76.9%) still preferred reduced palatal coverage at the end of the second year. The provision of maxillary 3-implant overdentures to oppose mandibular 2-implant overdentures significantly improve levels of patient

  14. Intra-arterial port implantation for intra-arterial chemotherapy : comparison between PIPS(Percutaneously Implantable Port System) and port system

    International Nuclear Information System (INIS)

    Yoon, Sang Jin; Shim, Hyung Jin; Jung, Hun Young; Choi, Yong Ho; Kim, Yang Soo; Song, In Sup; Kwak, Byung Kook

    1999-01-01

    To compare the techniques and complications of intra-arterial port implantation for intra-arterial chemotherapy between PIPS and the port system. For intra-arterial port implantation, 27 cases in 27 patients were retrospectively evaluated using PIPS(PIPS-200, William Cook Europe, Denmark) while for 21 cases in 19 patients a pediatric venous port system(Port-A-Cath, 5.8F, SIMS Deltec, U. S. A.) was used. All intra-arterial port implantation was performed percuteneously in an angiographic ward. Hepatocellular carcinoma was diagnosed in 18 patients and hepatic metastasis in 16. Peripheral cholangiocarcinoma, and pancreatic gastric, ovarian, renal cell and colon carcinoma were included. We compared the techniques and complications between PIPS and the port system. The follow up period ranged from 23 to 494(mean, 163) days in PIPS and from 12 to 431(mean, 150) days in the port system. In all cases, intra-arterial port implantations were technically successful. Port catheter tips were located in the common hepatic artery(n=8), proper hepatic artery(n=7), right hepatic artery(n=5), gastroduodenal artery(n=2), left hepatic artery(n=1), pancreaticoduodenal artery(n=1), inferior mesenteric artery(n=1), lumbar artery(n=1), and renal artery(n=1) in PIPS, and in the proper hepatic artery(n=6), gastroduodenal artery(n=6), common hepatic artery(n=3), right hepatic artery(n=4), inferior mesenteric artery(n=1), and internal iliac artery(n=1) in the port system. Port chambers were buried in infrainguinal subcutaneous tissue. Using PIPS, complications developed in seven cases(25.9%) and of these, four (57.1%) were catheter or chamber related. In the port system, catheter or chamber related complications developed in four cases(19.0%). Because PIPS and the port system have relative merits and demetrits, successful intra-arterial port implantation is possible if equipment is properly selected

  15. Attachment systems for mandibular implant overdentures: a systematic review

    Science.gov (United States)

    Kim, Ha-Young; Lee, Jeong-Yol; Bryant, S. Ross

    2012-01-01

    PURPOSE The aim of this systematic review was to address treatment outcome according to attachment systems for mandibular implant overdentures in terms of implant survival rate, prosthetic maintenance and complications, and patient satisfaction. MATERIALS AND METHODS A systematic literature search was conducted using PubMed and hand searching of relevant journals considering inclusion and exclusion criteria. Clinical trial studies on mandibular implant overdentures until August, 2010 were selected if more than one type of overdenture attachment was reported. Twenty four studies from 1098 studies were finally included and the data on implant survival rate, prosthetic maintenance and complications, patient satisfaction were analyzed relative to attachment systems. RESULTS Four studies presented implant survival rates (95.8 - 97.5% for bar, 96.2 - 100% for ball, 91.7% for magnet) according to attachment system. Ten other studies presented an implant survival rate ranging from 93.3% to 100% without respect to the attachment groups. Common prosthetic maintenance and complications were replacement of an assay for magnet attachments, and activation of a matrix or clip for ball or bar attachments. Prosthetic maintenance and complications most commonly occurred in the magnet groups. Conflicting findings were found on the rate of prosthetic maintenance and complications comparing ball and bar attachments. Most studies showed no significant differences in patient satisfaction depending upon attachment systems. CONCLUSION The implant survival rate of mandibular overdentures seemed to be high regardless attachment systems. The prosthetic maintenance and complications may be influenced by attachment systems. However patient satisfaction may be independent of the attachment system. PMID:23236571

  16. Anterior cruciate ligament reconstruction in a rabbit model using silk-collagen scaffold and comparison with autograft.

    Directory of Open Access Journals (Sweden)

    Fanggang Bi

    Full Text Available The objective of the present study was to perform an in vivo assessment of a novel silk-collagen scaffold for anterior cruciate ligament (ACL reconstruction. First, a silk-collagen scaffold was fabricated by combining sericin-extracted knitted silk fibroin mesh and type I collagen to mimic the components of the ligament. Scaffolds were electron-beam sterilized and rolled up to replace the ACL in 20 rabbits in the scaffold group, and autologous semitendinosus tendons were used to reconstruct the ACL in the autograft control group. At 4 and 16 weeks after surgery, grafts were retrieved and analyzed for neoligament regeneration and tendon-bone healing. To evaluate neoligament regeneration, H&E and immunohistochemical staining was performed, and to assess tendon-bone healing, micro-CT, biomechanical test, H&E and Russell-Movat pentachrome staining were performed. Cell infiltration increased over time in the scaffold group, and abundant fibroblast-like cells were found in the core of the scaffold graft at 16 weeks postoperatively. Tenascin-C was strongly positive in newly regenerated tissue at 4 and 16 weeks postoperatively in the scaffold group, similar to observations in the autograft group. Compared with the autograft group, tendon-bone healing was better in the scaffold group with trabecular bone growth into the scaffold. The results indicate that the silk-collagen scaffold has considerable potential for clinical application.

  17. Soft and Firm Alloplastic Implants in Rhinoplasty: Why, When and How to Use Them: A Review of 311 Cases.

    Science.gov (United States)

    Fanous, Nabil; Tournas, Athanasios; Côté, Valérie; Ali, Yaseen; Berbari, Patricia; Fanous, Amanda; Campagna-Vaillancourt, Maude

    2017-04-01

    Modern rhinoplasty is not just a reduction procedure. An optimal nasal esthetic result occasionally requires augmenting the nasal tip, the dorsum or the lateral wall with autografts or alloplasts. A large number of nasal implant types have been reported in the medical literature. The goal of this article is to demystify the role and indications of nasal implants in rhinoplasty. As well, it offers both the novice and experienced nasal surgeon a basic, simplified and organized approach to the use of soft and firm nasal implants in rhinoplasty. This article presents the authors experience with 311 rhinoplasties using both soft and firm alloplastic implants. The indications for both types of alloplasts are discussed, the surgical technique detailed and the outcomes analyzed. A total of 311 nasal implant cases were reviewed. This series revealed a low incidence of postoperative infection (5.57% for soft implants and 0.1% for the firm ones). The revision rate was 2.7% for the soft implants group and 7.1% for the firm implants group. This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

  18. Systemic alendronate treatment improves fixation of press-fit implants: a canine study using nonloaded implants

    DEFF Research Database (Denmark)

    Jensen, Thomas B; Bechtold, Joan E; Chen, Xinqian

    2007-01-01

    of alendronate treatment. Bone ongrowth (bone in contact with implant surface) was estimated using the linear intercept technique and shear strength was calculated as the slope on a load-displacement curve. For the press fit implants, alendronate treatment significantly increased bone ongrowth from 24% to 29...... early implant stability is an important predictor of longevity, systemic alendronate treatment could be an important clinical tool to positively influence the early stages of implant incorporation. Udgivelsesdato: 2007-Jun...

  19. Which is the best method of sterilization for recycled bone autograft in limb salvage surgery: a radiological, biomechanical and histopathological study in rabbit.

    Science.gov (United States)

    Yasin, Nor Faissal; Ajit Singh, Vivek; Saad, Marniza; Omar, Effat

    2015-04-15

    Limb salvage surgery is a treatment of choice for sarcomas of the extremities. One of the options in skeletal reconstruction after tumour resection is by using a recycled bone autograft. The present accepted methods of recycling bone autografts include autoclaving, pasteurization and irradiation. At the moment there is lack of studies that compare the effectiveness of various sterilization methods used for recycling bone autografts and their effects in terms of bone incorporation. This study was performed to determine the effects of different methods of sterilization on bone autografts in rabbit by radiological, biomechanical and histopathological evaluations. Fresh rabbit cortical bone is harvested from the tibial diaphysis and sterilized extracorporeally by pasteurization (n = 6), autoclaving (n = 6), irradiation (n = 6) and normal saline as control group (n = 6). The cortical bones were immediately reimplanted after the sterilization process. The subsequent process of graft incorporation was examined over a period of 12 weeks by serial radiographs, biomechanical and histopathological evaluations. Statistical analysis (ANOVA) was performed on these results. Significance level (α) and power (β) were set to 0.05 and 0.90, respectively. Radiographic analysis showed that irradiation group has higher score in bony union compared to other sterilization groups (p = 0.041). ANOVA analysis of 'failure stress', 'modulus' and 'strain to failure' demonstrated no significant differences (p = 0.389) between treated and untreated specimens under mechanical loading. In macroscopic histopathological analysis, the irradiated group has the highest percentage of bony union (91.7 percent). However in microscopic analysis of union, the pasteurization group has significantly higher score (p = 0.041) in callus formation, osteocytes percentage and bone marrow cellularity at the end of the study indicating good union potential. This experimental study shown that both irradiation and

  20. Wireless energizing system for an automated implantable sensor

    Energy Technology Data Exchange (ETDEWEB)

    Swain, Biswaranjan; Nayak, Praveen P.; Kar, Durga P.; Bhuyan, Satyanarayan; Mishra, Laxmi P. [Department of Electronics and Instrumentation Engineering, Siksha ‘O’ Anusandhan University, Bhubaneswar 751030 (India)

    2016-07-15

    The wireless drive of an automated implantable electronic sensor has been explored for health monitoring applications. The proposed system comprises of an automated biomedical sensing system which is energized through resonant inductive coupling. The implantable sensor unit is able to monitor the body temperature parameter and sends back the corresponding telemetry data wirelessly to the data recoding unit. It has been observed that the wireless power delivery system is capable of energizing the automated biomedical implantable electronic sensor placed over a distance of 3 cm from the power transmitter with an energy transfer efficiency of 26% at the operating resonant frequency of 562 kHz. This proposed method ensures real-time monitoring of different human body temperatures around the clock. The monitored temperature data have been compared with a calibrated temperature measurement system to ascertain the accuracy of the proposed system. The investigated technique can also be useful for monitoring other body parameters such as blood pressure, bladder pressure, and physiological signals of the patient in vivo using various implantable sensors.

  1. Wireless energizing system for an automated implantable sensor

    International Nuclear Information System (INIS)

    Swain, Biswaranjan; Nayak, Praveen P.; Kar, Durga P.; Bhuyan, Satyanarayan; Mishra, Laxmi P.

    2016-01-01

    The wireless drive of an automated implantable electronic sensor has been explored for health monitoring applications. The proposed system comprises of an automated biomedical sensing system which is energized through resonant inductive coupling. The implantable sensor unit is able to monitor the body temperature parameter and sends back the corresponding telemetry data wirelessly to the data recoding unit. It has been observed that the wireless power delivery system is capable of energizing the automated biomedical implantable electronic sensor placed over a distance of 3 cm from the power transmitter with an energy transfer efficiency of 26% at the operating resonant frequency of 562 kHz. This proposed method ensures real-time monitoring of different human body temperatures around the clock. The monitored temperature data have been compared with a calibrated temperature measurement system to ascertain the accuracy of the proposed system. The investigated technique can also be useful for monitoring other body parameters such as blood pressure, bladder pressure, and physiological signals of the patient in vivo using various implantable sensors.

  2. Wireless energizing system for an automated implantable sensor.

    Science.gov (United States)

    Swain, Biswaranjan; Nayak, Praveen P; Kar, Durga P; Bhuyan, Satyanarayan; Mishra, Laxmi P

    2016-07-01

    The wireless drive of an automated implantable electronic sensor has been explored for health monitoring applications. The proposed system comprises of an automated biomedical sensing system which is energized through resonant inductive coupling. The implantable sensor unit is able to monitor the body temperature parameter and sends back the corresponding telemetry data wirelessly to the data recoding unit. It has been observed that the wireless power delivery system is capable of energizing the automated biomedical implantable electronic sensor placed over a distance of 3 cm from the power transmitter with an energy transfer efficiency of 26% at the operating resonant frequency of 562 kHz. This proposed method ensures real-time monitoring of different human body temperatures around the clock. The monitored temperature data have been compared with a calibrated temperature measurement system to ascertain the accuracy of the proposed system. The investigated technique can also be useful for monitoring other body parameters such as blood pressure, bladder pressure, and physiological signals of the patient in vivo using various implantable sensors.

  3. The Biolink Implantable Telemetry System

    Science.gov (United States)

    Betancourt-Zamora, Rafael J.

    1999-01-01

    Most biotelemetry applications deal with the moderated data rates of biological signals. Few people have studied the problem of transcutaneous data transmission at the rates required by NASA's Life Sciences-Advanced BioTelemetry System (LS-ABTS). Implanted telemetry eliminate the problems associated with wire breaking the skin, and permits experiments with awake and unrestrained subjects. Our goal is to build a low-power 174-216MHz Radio Frequency (RF) transmitter suitable for short range biosensor and implantable use. The BioLink Implantable Telemetry System (BITS) is composed of three major units: an Analog Data Module (ADM), a Telemetry Transmitter Module (TTM), and a Command Receiver Module (CRM). BioLink incorporates novel low-power techniques to implement a monolithic digital RF transmitter operating at 100kbps, using quadrature phase shift keying (QPSK) modulation in the 174-216MHz ISM band. As the ADM will be specific for each application, we focused on solving the problems associated with a monolithic implementation of the TTM and CRM, and this is the emphasis of this report. A system architecture based on a Frequency-Locked Loop (FLL) Frequency Synthesizer is presented, and a novel differential frequency that eliminates the need for a frequency divider is also shown. A self sizing phase modulation scheme suitable for low power implementation was also developed. A full system-level simulation of the FLL was performed and loop filter parameters were determined. The implantable antenna has been designed, simulated and constructed. An implant package compatible with the ABTS requirements is also being proposed. Extensive work performed at 200MHz in 0.5um complementary metal oxide semiconductors (CMOS) showed the feasibility of integrating the RF transmitter circuits in a single chip. The Hajimiri phase noise model was used to optimize the Voltage Controlled Oscillator (VCO) for minimum power consumption. Two test chips were fabricated in a 0.5pm, 3V CMOS

  4. Functional assessment of hepatocytes after transplantation into rat spleen

    International Nuclear Information System (INIS)

    Woods, R.J.; Fuller, B.J.; Attenburrow, V.D.; Nutt, L.H.; Hobbs, K.E.

    1982-01-01

    The retention of structural integrity and metabolic function by isolated hepatocytes after ectopic transplantation has been investigated in autografted rats. Rats were partially hepatectomized and isolated hepatocytes prepared from the excised liver lobes were implanted into their spleens. Histological examination of the spleens 7 or more weeks after implantation revealed aggregates of hepatocytes in the red pulp. Two tests of biochemical function were applied to the hepatocytes after transplantation. In the first the hepatobiliary imaging agent technetium-99m N-[N'-(2, 6-dimethylphenyl)carbamoylmethyl]iminodiacetic acid (99mTc HIDA), which was shown to be avidly taken up by isolated hepatocytes in vitro, was infused into the tail veins of autograft and control rats. Radioactivity accumulating in the spleens of autografted rats was markedly greater than that in controls implanted with lethally damaged cells or in nontransplanted rats. In the second the presence of bilirubin metabolites was sought in autograft spleens after intravenous infusion of bilirubin. Both mono- and diglucuronides of bilirubin were recovered from the spleens of autograft rats but no conjugates were recovered from the spleens of unoperated controls. We conclude that after autotransplantation isolated hepatocytes retain their morphology and at least some of their functional activities

  5. Early and mid-term results of autograft rescue by Ross reversal: A one-valve disease need not become a two-valve disease.

    Science.gov (United States)

    Hussain, Syed T; Majdalany, David S; Dunn, Aaron; Stewart, Robert D; Najm, Hani K; Svensson, Lars G; Houghtaling, Penny L; Blackstone, Eugene H; Pettersson, Gösta B

    2018-02-01

    Risk of reoperation and loss of a second native valve are major drawbacks of the Ross operation. Rather than discarding the failed autograft, it can be placed back into the native pulmonary position by "Ross reversal." We review our early and mid-term results with this operation. From 2006 to 2017, 39 patients underwent reoperation for autograft dysfunction. The autograft was successfully rescued in 35 patients: by Ross reversal in 30, David procedure in 4, and autograft repair in 1. Medical records were reviewed for patient characteristics (mean age was 46 ± 13 years, range 18-67 years, and 23 were male), previous operations, indications for reoperation, hospital outcomes, and echocardiographic findings for the 30 patients undergoing successful Ross reversal. Follow-up was 4.1 ± 3.5 years (range 7 months-11 years). Median interval between the original Ross procedure and Ross reversal was 12 years (range 5-19 years). Eight patients also had absolute indications for replacement of the pulmonary allograft. There was no operative mortality. One patient required reoperation for bleeding. Another had an abdominal aorta injury from use of an endoballoon clamp. There was no other major postoperative morbidity, and median postoperative hospital stay was 7.2 days (range 4-41 days). No patient required reoperation during follow-up. Twenty-four patients had acceptable pulmonary valve function, and 6 had clinically well-tolerated moderate or severe pulmonary regurgitation. Ross reversal can be performed with low morbidity and acceptable pulmonary valve function, reducing patient risk of losing 2 native valves when the autograft fails in the aortic position. Copyright © 2017 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  6. Systemic Assessment of Patients Undergoing Dental Implant ...

    African Journals Online (AJOL)

    Background: Procedure‑related and patient‑related factors influence the prognosis of dental implants to a major extent. Hence, we aimed to evaluate and analyze various systemic factors in patients receiving dental implants. Materials and Methods: Fifty‑one patients were included in the study, in which a total of 110 dental ...

  7. Analytical and experimental position stability of the abutment in different dental implant systems with a conical implant?abutment connection

    OpenAIRE

    Semper-Hogg, Wiebke; Kraft, Silvan; Stiller, Sebastian; Mehrhof, Juergen; Nelson, Katja

    2012-01-01

    Objectives Position stability of the abutment should be investigated in four implant systems with a conical implant?abutment connection. Materials and methods Previously developed formulas and an established experimental setup were used to determine the position stability of the abutment in the four implant systems with a conical implant?abutment connection and different positional index designs: The theoretical rotational freedom was calculated by using the dimensions of one randomly selecte...

  8. [Acute transformation of chronic myeloid leukemia: disappearance of the Philadelphia chromosome after autograft].

    Science.gov (United States)

    Reiffers, J; David, B; Bernard, P; Vezon, G; Marit, G; Moulinier, J; Broustet, A

    1984-04-12

    Two patients with chronic granulocytic leukemia (C.G.L.) undergoing transformation were treated by high dose chemotherapy and total body irradiation followed by autografting of hematopoietic stem cells collected and cryo-preserved at the time of diagnosis. Recovery of hematopoiesis was characterized by disappearance of the Philadelphia chromosome in most metaphases. A new approach of the management of C.G.L. is discussed.

  9. Reparação traqueal em cães: transplante autógeno vs implante homógeno conservado em glicerina a 98% de cartilagem da pina Tracheal healing in dogs: autograft versus homograft implant preserved in 98% glycerin of pinna cartilage

    Directory of Open Access Journals (Sweden)

    Emerson Antonio Contesini

    2001-08-01

    them were submitted to an autograft (group I and six to homograft preserved in 98% glycerin (group II, to repair tracheal defects. One third of three cervical tracheal rings were removed and substituted for auto or homograft. These animals remained under observation and clinical evaluation in rest and moderate physical exercise during a 45 days period, without presenting any decurrent complications. At the end of the observation period, the trachea was submitted to gross and microscopic examination. Full epithelization of the grafted area was observed by macroscopic evaluation in both groups. Microscopic analyses showed granulation tissue in the transplanted area of group I, the lamina propria with moderate infiltration of neutrophile and few fibrosis with focus of epithelial hyperplasia. Animals of group II presented granulation around the area of the implantation and discrete invasion of macrophages and neomorph vases in the lamina propria, with moderate inflammation. The epithelium showed no alteration. These data suggest that the pinna cartilage homograft implant induce less aggressive response by the receiving streambed, even so this was not observed grossly.

  10. Glycogen accumulation in normal and irradiated minced muscle autografts on frog gastrocnemius

    International Nuclear Information System (INIS)

    Malhotra, R.K.; Kaul, R.; Malhotra, N.

    1989-01-01

    Alterations induced in glycogen content and phosphorylase activity have been studied in normal and irradiated minced muscle autografts on frog gastrocnemius at days 1, 3, 5, 7, 10, 15 and 30 postgrafting. The changes observed in the glycogen content and phosphorylase activity conform to the degeneration and regeneration phases of muscle repair. An attempt has been made to explain the altered glycogen utilizing capacities of the frog skeletal muscle during its repair and regeneration. (author)

  11. Implantable power generation system utilizing muscle contractions excited by electrical stimulation.

    Science.gov (United States)

    Sahara, Genta; Hijikata, Wataru; Tomioka, Kota; Shinshi, Tadahiko

    2016-06-01

    An implantable power generation system driven by muscle contractions for supplying power to active implantable medical devices, such as pacemakers and neurostimulators, is proposed. In this system, a muscle is intentionally contracted by an electrical stimulation in accordance with the demands of the active implantable medical device for electrical power. The proposed system, which comprises a small electromagnetic induction generator, electrodes with an electrical circuit for stimulation and a transmission device to convert the linear motion of the muscle contractions into rotational motion for the magneto rotor, generates electrical energy. In an ex vivo demonstration using the gastrocnemius muscle of a toad, which was 28 mm in length and weighed 1.3 g, the electrical energy generated by the prototype exceeded the energy consumed for electrical stimulation, with the net power being 111 µW. It was demonstrated that the proposed implantable power generation system has the potential to replace implantable batteries for active implantable medical devices. © IMechE 2016.

  12. Sistema de fabrico rápido de implantes ortopédicos Rapid manufacturing system of orthopedics implants

    Directory of Open Access Journals (Sweden)

    Carlos Relvas

    2009-06-01

    /CAM system. After sterilization, the implant is able to be placed on the patient. The concept was developed using low cost technology and commercially available. The system has been tested in an in vivo hip arthroplasty performed on a sheep. The time increase of surgery was 80 minutes being 40 minutes the time of implant manufacturing. The system developed has been tested and the goals defined of the study achieved enabling the rapid manufacture of an implant in a time period compatible with the surgery time.

  13. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad

    2013-12-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  14. Implantable intraocular pressure monitoring systems: Design considerations

    KAUST Repository

    Arsalan, Muhammad; Ouda, Mahmoud H.; Marnat, Loic; Shamim, Atif; Salama, Khaled N.

    2013-01-01

    Design considerations and limitations of implantable Intraocular Pressure Monitoring (IOPM) systems are presented in this paper. Detailed comparison with the state of the art is performed to highlight the benefits and challenges of the proposed design. The system-on-chip, presented here, is battery free and harvests energy from incoming RF signals. This low-cost design, in standard CMOS process, does not require any external components or bond wires to function. This paper provides useful insights to the designers of implantable wireless sensors in terms of design choices and associated tradeoffs. © 2013 IEEE.

  15. [Comparative evaluation of two kinds of micro-implant system with different size].

    Science.gov (United States)

    Wang, Zhen-Dong; Li, Qing-Yi; Wang, Lin; Gu, Yong-Jia

    2009-04-01

    To offer some reference for micro-implant's development and population by analyzing clinical application of two kinds of micro-implant systems. 38 patients treated with MIA (micro-implant anchorage) and 28 patients treated with SDIA (self-driven titanium implant for orthodontic anchorage) were included. Analyzing the rate of lost implants, the gum's reactivity and the efficiency of moving teeth summarized the excellences and shortcomings of two systems. 1) Six of MIA implants fell off after being inserted. Seven of SDIA implants lost when they had been implanted for a month. But they were stable after being inserted again. 2) The gum around 12 SDIA implants got inflammation symptom, but the gum around MIA implants was normal. 3) Both MIA implants and SDIA implants could move teeth effectively and persistently when they were stable. When we apply micro-implant in clinic, we should prevent it from closing roots of teeth and choose the small tip micro-implant. The embedded position should be in area of attachment gum. At the same time, the areas around the tip of micro-implant should be keeping clean.

  16. When the tendon autograft is dropped accidently on the floor: A study about bacterial contamination and antiseptic efficacy.

    Science.gov (United States)

    Barbier, O; Danis, J; Versier, G; Ollat, D

    2015-10-01

    Inadvertent contamination of the autograft can occur during anterior cruciate ligament (ACL) reconstruction if the autograft is dropped on the floor during surgery. A study was undertaken to determine the incidence of contamination when a graft is dropped on the operating room floor and the efficacy of antimicrobial solutions to decontaminate it. Samples from 25 patients undergoing ACL reconstruction with a hamstring tendon were sectioned and dropped onto the floor. Cultures were taken after immersion in antiseptic solutions (a chlorhexidine gluconate solution (group 1), a povidone-iodine solution (group 2), and a sodium hypochlorite solution (group 3)). A fourth piece (group 0) was cultured without being exposed to any solution. Cultures of a floor swab were taken at the same time. The floor swab cultures were positive in 96% of cases. The rate of contamination was 40% in group 0, 8% in group 1, 4% in group 2, and 16% in group 3. There was a significant difference between groups 1 and 2 and group 0 (p<0.05) but not between groups 3 and 0. Immersing a graft dropped on the floor during surgery in a chlorhexidine gluconate solution or povidone-iodine solution significantly reduces contamination of the graft. Soaking of the hamstring autograft in one of these solutions is recommended in the case of inadvertent contamination. Laboratory investigation (level 2). Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Clinical application of single-tooth replacement with ankylos implant system

    International Nuclear Information System (INIS)

    Yang Xu; Liu Xue; Zhang Heng; Deng Yan; Guo Zhaozhong; Zhang Yufeng

    2011-01-01

    Objective: To evaluate the clinical effects of Ankylos implant system to restore the loss of single-tooth. Methods: 90 cases with loss of single-tooth were selected and treated with routinely two-stage surgery. When the patients presented with deficient alveolar ridge, guided bone regeneration (GBR), osteotome sinus floor elevation, lateral antrostomy surgery with simultaneous placement of implant were applied. They were restored with platinum ceramic crown. All the implants were followed up, and the records were kept about stability of the implant and abutment, the status of surrounding soft tissue, sealability of implant abutment junction and the marginal bone lossing through X-ray checking,and satisfaction of the patients to mastication and aspect of the restorations. The follow-up time was 1-2.5 years. Results: Among the cases,one case had peri-implant inflammation, and one case had porcelain dropped. No loosening occurred in the other implants and abuments. Implant abutment junction was sealed well. The marginal bone loss 1 year after final restoration was less than 1 mm. Soft tissue surrounding implants was healthy. The satisfaction rate was 98.9% (89/90). According to standard of implant success, 88 cases were successful, the 2.5-year cumulative success rate was 97.8%, 2 cases failed, and the failure rate was 2.2 %. Conclusion: A satisfactory treatment effects could be gotten by using Ankylos implant system to restore the loss of single-tooth. (authors)

  18. Ipsilateral femoral autograft reconstruction after resection of a pelvic tumor.

    Science.gov (United States)

    Biau, David J; Thévenin, Fabrice; Dumaine, Valérie; Babinet, Antoine; Tomeno, Bernard; Anract, Philippe

    2009-01-01

    Reconstruction of bone after the resection of a pelvic tumor is challenging. The purpose of the present study was to evaluate the use of the ipsilateral femur as the graft material for reconstruction. We performed a retrospective review of thirteen patients with a malignant pelvic lesion who underwent resection followed by reconstruction with an ipsilateral femoral autograft and insertion of a total hip replacement. The study group included nine men and four women with a median age of fifty-one years at the time of the reconstruction. The diagnosis was chondrosarcoma in eight patients, metastasis in three, and myeloma and radiation-induced malignant disease in one each. The surviving patients were assessed functionally and radiographically; the cumulative probability of revision was estimated while taking into account competing risks. The median duration of follow-up was forty-nine months. At the time of the latest follow-up, seven patients were alive and disease-free and six had died from metastatic disease. Four patients had had revision of the reconstruction, two for the treatment of mechanical complications and two for the treatment of infection. Three other patients had mechanical complications but had not had a revision. The cumulative probability of revision of the reconstruction for mechanical failure was 8% (95% confidence interval, 0% to 23%), 8% (95% confidence interval, 0% to 23%), and 16% (95% confidence interval, 0% to 39%) at one, two, and four years, respectively. Although it has attendant complications consistent with pelvic tumor surgery, an ipsilateral femoral autograft reconstruction may be an option for reconstruction of pelvic discontinuity in a subgroup of patients following tumor resection. This innovative procedure requires longer-term follow-up studies.

  19. OP-1 compared with iliac crest autograft in instrumented posterolateral fusion a randomized, multicenter non-inferiority trial

    NARCIS (Netherlands)

    Delawi, Diyar; Jacobs, Wilco; Van Susante, Job L C; Rillardon, Ludovic; Prestamburgo, Domenico; Specchia, Nicola; Gay, Emmanuel; Verschoor, Nico; Garcia-Fernandez, Carlos; Guerado, Enrique; Van Ufford, Henriette Quarles; Kruyt, Moyo C.; Dhert, Wouter J A; Cumhur Oner, F.

    2016-01-01

    Background: Spinal fusion with the use of autograft is a commonly performed procedure. However, harvesting of bone from the iliac crest is associated with complications. Bone morphogenetic proteins (BMPs) are extensively used as alternatives, often without sufficient evidence of safety and efficacy.

  20. Retrospective study investigating the clinical success of two provisional implant systems

    OpenAIRE

    Hotz, Nadine

    2011-01-01

    The use of dental implants allows a reliable stabilisation of prosthesis. Usually, definitive implants can´t be used for fixation of prosthesis during their healing period. Therefore, in many cases it is not possible to follow the demand of patients of an immediate loading of definitive implants to avoid a unfixed dental prosthesis. This is one domain of provisional dental implants. The present study of two provisional implant systems approves the benefit of provisional implants during...

  1. Mitral Valve Replacement with a Pulmonary Autograft in an Infant

    Directory of Open Access Journals (Sweden)

    Yong Ho Jeong

    2018-04-01

    Full Text Available A 76-day-old infant weighing 3.4 kg was referred for surgical intervention for severe mitral valve stenoinsufficiency caused by leaflet fibrosis and calcification. He had experienced a cerebral infarction in the left middle cerebral artery territory, which was deemed attributable to an embolism of a calcified particle from the dysmorphic mitral valve. Because mitral valve replacement using a prosthetic valve was not feasible in this small baby, mitral valve replacement with a pulmonary autograft was performed. After a brief period of extracorporeal membrane oxygenation (ECMO support, he was weaned from ECMO and was discharged home without further cardiovascular complications.

  2. Clinical results of primary malignant musculoskeletal tumor treated by wide resection and recycling autograft reconstruction using liquid nitrogen.

    Science.gov (United States)

    Paholpak, Permsak; Sirichativapee, Winai; Wisanuyotin, Taweechok; Kosuwon, Weerachai; Jeeravipoolvarn, Polasak

    2015-06-01

    To evaluate the clinical results of primary malignant musculoskeletal tumors treated with wide resection and recycling autograft reconstruction using liquid nitrogen. We reviewed 12 patients who had a primary malignant bone and soft tissue tumor treated by wide resection and recycling autograft reconstruction using liquid nitrogen between March 2006 and March 2013. The results were judged by recurrence, functional status and complications. Functional status was assessed according to the Musculoskeletal Tumor Society Score (MSTSS). Clinical failure was defined as need for reoperation in order to change the type of reconstruction or to amputate, and the presence of local recurrence. The most common tumor was osteosarcoma (eight cases) followed by Ewing's sarcoma (two cases). The tibia was the most frequently involved skeletal site (six cases) followed by the femur (three cases). The median follow-up period was 32 months. In 12 patients, 7 were still alive without recurrence. There were 3 clinical failures: 1 local recurrence and 2 graft complications at 28, 51 and 20 months after reconstruction, respectively. The main complication was infection (three cases). All osteotomy sites were radiographic unions, and the union time was 8.2 ± 2.7 months. The mean ± SD MSTSS score was 79% ± 11%; excellent functional results were achieved in seven patients. Recycling autograft reconstruction using liquid nitrogen had favorable clinical outcomes in terms of functional status and local recurrence. This reconstruction method, therefore, represents a reasonable alternative for limb salvage surgery. © 2014 Wiley Publishing Asia Pty Ltd.

  3. Friction wear and dissolution of orthopedic implant systems

    International Nuclear Information System (INIS)

    Ektessabi, A.M.; Shikine, S.; Hamdi, M.; Kitamura, N.; Rokkum, M.; Johansson, C.

    2000-01-01

    Bio-medical implants release metallic elements during the long periods of time while inserted in the human body. The chemical interactions between the tissues and surface of the implants, and the mechanical friction of implants cause the release of metals into the human tissues. In this study we investigated the distribution and the chemical-state of the metallic elements in the tissues around a failed implant system using PIXE (proton induced x-ray emission) and SR-XRF (synchrotron radiation x-ray fluorescence) spectroscopies. The specimens were from the causes of patients with diagnosed arthritis. The implant consisted of a stem and a metal backing made of Ti-6Al-4V, an implant head made of stainless steel, and a polyethylene (PE) cup. Both the stem and the metal backing had a plasma-sprayed HAp surface coating. Distribution and concentration of dissolved elements in tissues surrounding implants were examined and quantified using PIXE analysis. Similar specimen from the same case was further investigated using SR-XRF analysis. Chemical-states of the dissolved elements were also studied by XAFS (x-ray absorption fine structure) analysis. From results of these measurements, it is confirmed that the tissues surrounding implants contained metallic elements such as Fe, Cr, Ni, and Ti. These elements are originated from the implant. Furthermore, it was made clear that the chemical-state of Fe had changed as a consequence of dissolution of Fe in the organic tissues. (author)

  4. Systemic conditions and treatments as risk for therapy with dental implants

    International Nuclear Information System (INIS)

    Arguedas Vega, Natalia; Alfaro Mayorga, Erika

    2013-01-01

    The possible risks for osseointegration are described in patients with specific systemic conditions, medical treatment such as radiation, cardiovascular diseases, HIV and smoking habit. The principal complications for osseointegration of diseases and systemic treatments are exposed. The review and search of the available literature are realized in databases. The scientific literature obtained from human studies has reported the survival of patients with dental implants. The implants are placed in patients with at least one of the conditions studied. The risks of the surgical procedures required for the placement of implants are analyzed in systemically compromised patients. Comparisons of patients with and without systemic conditions in controlled form have remained without analyzing. The level of evidence of absolute and relative contraindications has been low for the therapy with implants in patients with systemic diseases. The revised information is detailed according the systemic conditions, and each of them are evaluated separately [es

  5. Therapeutic interaction of systemically-administered mesenchymal stem cells with peri-implant mucosa.

    Directory of Open Access Journals (Sweden)

    Ryosuke Kondo

    Full Text Available OBJECTIVES: The objective of this study was to investigate the effect of systemically transplanted mesenchymal stem cells (MSCs on the peri-implant epithelial sealing around dental implants. MATERIALS AND METHODS: MSCs were isolated from bone marrow of donor rats and expanded in culture. After recipient rats received experimental titanium dental implants in the bone sockets after extraction of maxillary right first molars, donor rat MSCs were intravenously transplanted into the recipient rats. RESULTS: The injected MSCs were found in the oral mucosa surrounding the dental implants at 24 hours post-transplantation. MSC transplantation accelerated the formation of the peri-implant epithelium (PIE-mediated mucosa sealing around the implants at an early stage after implantation. Subsequently, enhanced deposition of laminin-332 was found along the PIE-implant interface at 4 weeks after the replacement. We also observed enhanced attachment and proliferation of oral mucous epithelial cells. CONCLUSION: Systemically transplanted MSCs might play a critical role in reinforcing the epithelial sealing around dental implants.

  6. The Computer in a Programmable Implantable Medication System (PIMS)

    OpenAIRE

    Sanders, K. H.; Radford, W. E.

    1982-01-01

    The Programmable Implantable Medication System (PIMS) developed at APL can be used in the treatment of diabetes, reproductive hormone dysfunction, hypertension, cancer, chronic pain, thrombosis, and the delivery of growth hormone. The Implantable Programmable Infusion Pump (IPIP) is the implanted element of PIMS. Under control of a microprocessor, the IPIP administers medication and stores data pertaining to its operation. An external unit can read out the stored data, as well as program the ...

  7. A novel silk–TCP–PEEK construct for anterior cruciate ligament reconstruction: an off-the shelf alternative to a bone–tendon–bone autograft

    International Nuclear Information System (INIS)

    Li, Xiang; Snedeker, Jess G; He, Jiankang; Li, Dichen; Bian, Weiguo; Li, Zheng

    2014-01-01

    Bone–tendon–bone autograft represents a gold-standard for anterior cruciate ligament (ACL) reconstruction but at the cost of a secondary surgical site that can be accompanied by functional impairment and discomfort. Although numerous in vitro and in vivo studies have investigated tissue engineering alternatives to autografting, the achievement of a functional histological transition between soft and hard tissue has remained elusive. To bridge this gap we developed and tested a novel multiphase scaffold of silk, tricalcium phosphate (TCP) and polyether ether ketone for ACL reconstruction. We present in vitro biomechanical tests demonstrating that the construct recapitulates native ACL function under typical physiological loads. A pilot in vivo experiment in two pigs with a three-month follow-up showed a robust histological transition between regenerated fibrous tissue and the margins of the bone tunnel, with histological features similar to the native ACL to bone insertion. These histological observations suggest that the construct was stably anchored until TCP incorporation to the host tissues. On the strength of these preliminary results, we conclude that the described approach may offer a promising alternative to autograft for ACL reconstruction. This study thus provides proof for a concept that warrants further development. (paper)

  8. "Ride-on" technique and other simple and logical solutions to counter most common complications of silicone implants in augmentation rhinoplasty

    Directory of Open Access Journals (Sweden)

    Kapil S Agrawal

    2015-01-01

    Full Text Available Augmentation rhinoplasty can be carried out using a wide range of materials including autologous bone and/or cartilage as well as alloplasts. Use of biologic bone and cartilage grafts results in lower infection rates, but they are associated with long-term resorption and donor-site morbidity. Alloplastic materials, in particular silicone, have been associated in literature with extrusion, necrosis of the tip, mobility and deviation or displacement of the implant, immobile nasal tip and infection. However, they have the advantages of being readily available and easy to reshape with no requirement for harvesting autografts. Aim: To overcome these problems associated with silicone implants for which the authors have devised a novel technique, the "rideon technique". Materials and Methods: The present study was carried out on 11 patients over a period of 4 years. The authors have devised a simple technique to fix the silicone implant and retain it in place. Restricting the implant to only dorsum avoided common complications related to the silicone implant. Results: The authors have used this technique in 11 patients with encouraging results. Follow-up ranged from 12 months to 36 months during which patients were assessed for implant mobility, implant extrusion and tip necrosis. There was no incidence of above mentioned complications in these patients. Conclusion: The "rideon technique" provides excellent stability to silicone implants and restricting the implant only to dorsum not only eliminates chances of tip necrosis and thus implant extrusion but also maintains natural shape, feel and mobility of the tip.

  9. Effects of implant system, impression technique, and impression material on accuracy of the working cast.

    Science.gov (United States)

    Wegner, Kerstin; Weskott, Katharina; Zenginel, Martha; Rehmann, Peter; Wöstmann, Bernd

    2013-01-01

    This in vitro study aimed to identify the effects of the implant system, impression technique, and impression material on the transfer accuracy of implant impressions. The null hypothesis tested was that, in vitro and within the parameters of the experiment, the spatial relationship of a working cast to the placement of implants is not related to (1) the implant system, (2) the impression technique, or (3) the impression material. A steel maxilla was used as a reference model. Six implants of two different implant systems (Standard Plus, Straumann; Semados, Bego) were fixed in the reference model. The target variables were: three-dimensional (3D) shift in all directions, implant axis direction, and rotation. The target variables were assessed using a 3D coordinate measuring machine, and the respective deviations of the plaster models from the nominal values of the reference model were calculated. Two different impression techniques (reposition/pickup) and four impression materials (Aquasil Ultra, Flexitime, Impregum Penta, P2 Magnum 360) were investigated. In all, 80 implant impressions for each implant system were taken. Statistical analysis was performed using multivariate analysis of variance. The implant system significantly influenced the transfer accuracy for most spatial dimensions, including the overall 3D shift and implant axis direction. There was no significant difference between the two implant systems with regard to rotation. Multivariate analysis of variance showed a significant effect on transfer accuracy only for the implant system. Within the limits of the present study, it can be concluded that the transfer accuracy of the intraoral implant position on the working cast is far more dependent on the implant system than on the selection of a specific impression technique or material.

  10. Long-term retrospective study on the placement of the cementless acetabular cup and clinical outcomes in patients undergoing femoral head autografting for hip dysplasia and total hip arthroplasty.

    Science.gov (United States)

    Ozden, Vahit Emre; Dikmen, Goksel; Beksac, Burak; Tozun, Ismail Remzi

    2018-05-01

    Placement of acetabular cup in the dysplastic hip is a challenging procedure. Using bulk femoral head autograft to increase the bony coverage of the cup is one of the techniques, which have been described. The impact of cup position on cup and autograft survival is a controversial issue. We aimed to determine whether the position of cementless acetabular cup used in conjunction with femoral head autograft in dysplastic hips affected the autograft-host incorporation with its final radiographic appearance and the cup survivorship into the second decade. Thirty-eight dysplastic hips with varying Crowe types in 31 patients (30 women and one man) were included. The mean age was 47 years (range, 29-64 years) and the mean follow-up was 20.3 years (range, 14.8-25.9 years). The initial postoperative and final radiographs were evaluated. The survival rate of the cups was analysed using Kaplan-Meier statistics and the log-rank test. Multivariate analysis was used to evaluate the effect of variables (Crowe type, radiographic initial host bone coverage over the cup and position of the cup) on survivorship. The acetabular cups were positioned anatomical in 27/38 hips according to Ranawat measurement technique. Trabecular bridging at graft-host interface was seen in all cases at an average 22.1 months. Neither acetabular cup position nor initial host bone coverage over acetabular cup less than 50% had any significant effect on either cup survival or final radiographic appearance of the graft. The 20-year cup survival rate without aseptic revision was 66% (95 CI, 52%-84%). No revision was performed due to graft resorption. Twenty-year survival rate of the cementless cup combination with femoral head autograft showed no significant differences whether it was placed at high or anatomic hip centre. The final radiographic appearance of the autograft was not affected from either the cup location or the initial radiographic horizontal host bone coverage. Copyright © 2018 The Japanese

  11. Retention system for implant-supported dentures used by brazilian dentists who work in implant dentistry

    Directory of Open Access Journals (Sweden)

    Saturnino Aparecido Ramalho

    2010-04-01

    Full Text Available Objective: To provide the dentists with support in the choice of the cement or screw type of retention for implant-supported dentures, according to the patient’s problem. Methods: An opinion questionnaire was applied to a sample of 468 participants, all dentists working in the field of Implant Dentistry, of whom 272 (58.1% participated in the 4th International Congress of Osseointegration of APCD, held in São Paulo (SP from 6 to 9 May 2004, 119 (25.4% participated in the 2nd International Congress of Implant Dentistry of Minas Gerais, between 10 and 12 June 2004 and 77 (16.5% were professors and specialization and master students from São Leopoldo Mandic. Results: The results showed that 254 participants opted for the screw-retained system while 214 opted for the cement-retained system. Conclusion: There was a preference for the use of the screw-retained system, and that both cemented and screw-retained systems have advantages and disadvantages, so that the dentist is left to decide and evaluate them in order to indicate and use them with confidence in different clinical cases.

  12. Influence of abutment materials on the implant-abutment joint stability in internal conical connection type implant systems

    OpenAIRE

    Jo, Jae-Young; Yang, Dong-Seok; Huh, Jung-Bo; Heo, Jae-Chan; Yun, Mi-Jung; Jeong, Chang-Mo

    2014-01-01

    PURPOSE This study evaluated the influence of abutment materials on the stability of the implant-abutment joint in internal conical connection type implant systems. MATERIALS AND METHODS Internal conical connection type implants, cement-retained abutments, and tungsten carbide-coated abutment screws were used. The abutments were fabricated with commercially pure grade 3 titanium (group T3), commercially pure grade 4 titanium (group T4), or Ti-6Al-4V (group TA) (n=5, each). In order to assess ...

  13. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    Science.gov (United States)

    Malla, Tejsu; Jiang, Jing; Hu, Kai

    2018-01-01

    AIM To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT), conjunctival autograft transplantation (CAT) alone and amniotic membrane transplantation (AMT) alone. METHODS In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent) who underwent CAT (group A), AMT (group B) or CAT with AMT (group C) respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS The number of recurrence post-surgery were 17 (9 from primary, 8 from recurrent; the same description below), 18 (10, 8) and 2 (1, 1) in groups A, B, and C respectively; dry eyes were 22 (16, 6), 27 (18, 9) and 7 (3, 4); conjunctival inflammations were 30 (17, 13), 27 (16, 11) and 11 (6, 5). Patients in group C (either primary or recurrent or both) mainly showed significantly better results than those in group A or B (P<0.05) regarding above-mentioned clinical effects. CONCLUSION Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone. PMID:29600172

  14. Clinical outcome of combined conjunctival autograft transplantation and amniotic membrane transplantation in pterygium surgery

    Directory of Open Access Journals (Sweden)

    Tejsu Malla

    2018-03-01

    Full Text Available AIM: To compare long-term outcome of primary and recurrent pterygium surgery with three different techniques: combined conjunctival autograft and overlay amniotic membrane transplantation (CAT with AMT, conjunctival autograft transplantation (CAT alone and amniotic membrane transplantation (AMT alone. METHODS: In this retrospective study, 142 eyes of 142 pterygium patients (104 primary, 38 recurrent who underwent CAT (group A, AMT (group B or CAT with AMT (group C respectively following surgical excision were reviewed and compared based on the recurrences and post-operative complications. RESULTS: The number of recurrence post-surgery were 17 (9 from primary, 8 from recurrent; the same description below, 18 (10, 8 and 2 (1, 1 in groups A, B, and C respectively; dry eyes were 22 (16, 6, 27 (18, 9 and 7 (3, 4; conjunctival inflammations were 30 (17, 13, 27 (16, 11 and 11 (6, 5. Patients in group C (either primary or recurrent or both mainly showed significantly better results than those in group A or B (P<0.05 regarding above-mentioned clinical effects. CONCLUSION: Combined CAT and overly AMT have significantly lower rates of recurrence and postoperative complications for primary and recurrent pterygium surgery than CAT or AMT alone.

  15. The indications and donor-site morbidity of tibial cortical strut autografts in the management of defects in long bones.

    Science.gov (United States)

    Lauthe, O; Soubeyrand, M; Babinet, A; Dumaine, V; Anract, P; Biau, D J

    2018-05-01

    Aims The primary aim of this study was to determine the morbidity of a tibial strut autograft and characterize the rate of bony union following its use. Patients and Methods We retrospectively assessed a series of 104 patients from a single centre who were treated with a tibial strut autograft of > 5 cm in length. A total of 30 had a segmental reconstruction with continuity of bone, 27 had a segmental reconstruction without continuity of bone, 29 had an arthrodesis and 18 had a nonunion. Donor-site morbidity was defined as any event that required a modification of the postoperative management. Union was assessed clinically and radiologically at a median of 36 months (IQR, 14 to 74). Results Donor-site morbidity occurred in four patients (4%; 95% confidence interval (CI) 1 to 10). One patient had a stress fracture of the tibia, which healed with a varus deformity, requiring an osteotomy. Two patients required evacuation of a haematoma and one developed anterior compartment syndrome which required fasciotomies. The cumulative probability of union was 90% (95% CI 80 to 96) at five years. The type of reconstruction (p = 0.018), continuity of bone (p = 0.006) and length of tibial graft (p = 0.037) were associated with the time to union. Conclusion The tibial strut autograft has a low risk of morbidity and provides adequate bone stock for treating various defects of long bones. Cite this article: Bone Joint J 2018;100-B:667-74.

  16. The bacterial sealing capacity of morse taper implant-abutment systems in vitro.

    Science.gov (United States)

    Ranieri, Rogerio; Ferreira, Andreia; Souza, Emmanuel; Arcoverde, Joao; Dametto, Fabio; Gade-Neto, Cicero; Seabra, Flavio; Sarmento, Carlos

    2015-05-01

    The use of Morse taper systems in dental implantology has been associated widely with a more precise adaptation between implants and their respective abutments. This may lead to an increase in the stability of the implant system and may also prevent microbial invasion through the implant-abutment interface. The aim of this study was to investigate in vitro the ability of four commercially available Morse taper system units to impede bacterial penetration through their implant-abutment interfaces. Abutments were screwed onto the implants, and the units were subsequently immersed in Streptococcus sanguinis bacterial broth (1 × 10(8) colony forming units/mL) for 48 hours. The units were examined by scanning electron microscopy (SEM) under three conditions: 1) with the implant-abutment components assembled as units to investigate for both the existence of microgaps and the presence of bacteria; 2) with the implants and abutments separated for examination of internal surfaces; and 3) with the implant-abutment components again assembled as units to measure any microgaps detected. The mean size of the microgaps in each unit was determined by measuring, under SEM, their width in four equidistant points. Microgaps were detected in all units with no significant differences in dimension (Kruskal-Wallis test, P >0.05). Within all units, the presence of bacteria was also observed. The seals provided by the interfaces of the commercially available Morse taper implant-abutment units tested were not sufficiently small to shield the implant from bacterial penetration.

  17. Repair of sheep long bone cortical defects filled with COLLOSS, COLLOSS E, OSSAPLAST, and fresh iliac crest autograft.

    NARCIS (Netherlands)

    Huffer, W.E.; Benedict, J.J.; Turner, A.S.; Briest, A.; Rettenmaier, R.; Springer, M.; Walboomers, X.F.

    2007-01-01

    COLLOSS and COLLOSS E are osteoinductive bone void fillers consisting of bone collagen and noncollagenous proteins from bovine and equine bone, respectively. The aim of this study was to compare COLLOSS, COLLOSS E, iliac bone autograft, sintered beta tricalcium phosphate (beta-TCP; OSSAPLAST), and

  18. [Design and application of implantable medical device information management system].

    Science.gov (United States)

    Cao, Shaoping; Yin, Chunguang; Zhao, Zhenying

    2013-03-01

    Through the establishment of implantable medical device information management system, with the aid of the regional joint sharing of resources, we further enhance the implantable medical device traceability management level, strengthen quality management, control of medical risk.

  19. Sinking and fit of abutment of locking taper implant system

    Science.gov (United States)

    Moon, Seung-Jin; Kim, Hee-Jung; Son, Mee-Kyoung

    2009-01-01

    STATEMENT OF PROBLEM Unlike screw-retention type, fixture-abutment retention in Locking taper connection depends on frictional force so it has possibility of abutment to sink. PURPOSE In this study, Bicon® Implant System, one of the conical internal connection implant system, was used with applying loading force to the abutments connected to the fixture. Then the amount of sinking was measured. MATERIAL AND METHODS 10 Bicon® implant fixtures were used. First, the abutment was connected to the fixture with finger force. Then it was tapped with a mallet for 3 times and loads of 20 kg corresponding to masticatory force using loading application instrument were applied successively. The abutment state, slightly connected to the fixture without pressure was considered as a reference length, and every new abutment length was measured after each load's step was added. The amount of abutment sinking (mm) was gained by subtracting the length of abutment-fixture under each loading condition from reference length. RESULTS It was evident, that the amount of abutment sinking in Bicon® Implant System increased as loads were added. When loads of 20 kg were applied more than 5 - 7 times, sinking stopped at 0.45 ± 0.09 mm. CONCLUSION Even though locking taper connection type implant shows good adaption to occlusal force, it has potential for abutment sinking as loads are given. When locking taper connection type implant is used, satisfactory loads are recommended for precise abutment location. PMID:21165262

  20. Three-dimensional accuracy of plastic transfer impression copings for three implant systems.

    Science.gov (United States)

    Teo, Juin Wei; Tan, Keson B; Nicholls, Jack I; Wong, Keng Mun; Uy, Joanne

    2014-01-01

    The purpose of this study was to compare the three-dimensional accuracy of indirect plastic impression copings and direct implant-level impression copings from three implant systems (Nobel Biocare [NB], Biomet 3i [3i], and Straumann [STR]) at three interimplant buccolingual angulations (0, 8, and 15 degrees). Two-implant master models were used to simulate a three-unit implant fixed partial denture. Test models were made from Impregum impressions using direct implant-level impression copings (DR). Abutments were then connected to the master models for impressions using the plastic impression copings (INDR) at three different angulations for a total of 18 test groups (n = 5 in each group). A coordinate measuring machine was used to measure linear distortions, three-dimensional (3D) distortions, angular distortions, and absolute angular distortions between the master and test models. Three-way analysis of variance showed that the implant system had a significant effect on 3D distortions and absolute angular distortions in the x- and y-axes. Interimplant angulation had a significant effect on 3D distortions and absolute angular distortions in the y-axis. Impression technique had a significant effect on absolute angular distortions in the y-axis. With DR, the NB and 3i systems were not significantly different. With INDR, 3i appeared to have less distortion than the other systems. Interimplant angulations did not significantly affect the accuracy of NBDR, 3iINDR, and STRINDR. The accuracy of INDR and DR was comparable at all interimplant angulations for 3i and STR. For NB, INDR was comparable to DR at 0 and 8 degrees but was less accurate at 15 degrees. Three-dimensional accuracy of implant impressions varied with implant system, interimplant angulation, and impression technique.

  1. Depth of valve implantation, conduction disturbances and pacemaker implantation with CoreValve and CoreValve Accutrak system for Transcatheter Aortic Valve Implantation, a multi-center study.

    Science.gov (United States)

    Lenders, Guy D; Collas, Valérie; Hernandez, José Maria; Legrand, Victor; Danenberg, Haim D; den Heijer, Peter; Rodrigus, Inez E; Paelinck, Bernard P; Vrints, Christiaan J; Bosmans, Johan M

    2014-10-20

    Transcatheter Aortic Valve Implantation (TAVI) is now considered an indispensable treatment strategy in high operative risk patients with severe, symptomatic aortic stenosis. However, conduction disturbances and the need for Permanent Pacemaker (PPM) implantation after TAVI with the CoreValve prosthesis still remain frequent. We aimed to evaluate the implantation depth, the incidence and predictors of new conduction disturbances, and the need for PPM implantation within the first month after TAVI, using the new Accutrak CoreValve delivery system (ACV), compared to the previous generation CoreValve (non-ACV). In 5 experienced TAVI-centers, a total of 120 consecutive non-ACV and 112 consecutive ACV patients were included (n=232). The mean depth of valve implantation (DVI) was 8.4±4.0 mm in the non-ACV group and 7.1±4.0 mm in the ACV group (p=0.034). The combined incidence of new PPM implantation and new LBBB was 71.2% in the non-ACV group compared to 50.5% in the ACV group (p=0.014). DVI (p=0.002), first degree AV block (p=0.018) and RBBB (p<0.001) were independent predictors of PPM implantation. DVI (p<0.001) and pre-existing first degree AV-block (p=0.021) were identified as significant predictors of new LBBB. DVI is an independent predictor of TAVI-related conduction disturbances and can be reduced by using the newer CoreValve Accutrak delivery system, resulting in a significantly lower incidence of new LBBB and new PPM implantation. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  2. A COMPARATIVE STUDY BETWEEN SURGICAL OUTCOME OF PATIENT’S OWN BLOOD VS. 10-0 NYLON FOR CONJUNCTIVAL AUTOGRAFTING IN PTERYGIUM EXCISION

    Directory of Open Access Journals (Sweden)

    Ayush Mahendra

    2016-04-01

    Full Text Available CONTEXT (BACKGROUND Pterygium is a frequently occurring progressive ocular surface disorder which is a fleshy triangular wing shaped growth, encroaching from conjunctiva on cornea. Pterygium is frequent in hot, dry, dusty environment and prevalence is 0.3% to 29%. Surgical removal is main treatment for pterygium. The recurrence rate after pterygium surgery varies according to type of surgery. Various surgical modalities tried like simple excision, bare sclera technique, amniotic membrane transplantation and conjunctival autografting. AIM To compare surgical outcome of patient’s own blood Vs 10-0 Nylon for conjunctival autografting in pterygium excision. SETTINGS AND DESIGN It is a prospective randomised interventional control trial, with a sample size of minimum 30 patients in each group studied in a tertiary care hospital from Oct. 2013 to Dec. 2015. METHODS AND MATERIAL Out of 63 patients who underwent pterygium excision, patient’s own blood was used in 32 patients (Group A and 10-0 Nylon suture was used in 31 patients (Group B for conjunctival autografting. All patients were followed up regularly on postoperative day 1, 8, 30, 90 and 180. Variables for postoperative assessment were pain, watering, irritation, redness, graft displacement, graft loss and recurrence. STATISTICAL ANALYSIS Statistical analysis was performed using SPSS 13.0 (SPSS, Chicago. Outcome variables between the two groups were compared using the non-parametric Mann–Whitney U Test. RESULTS The mean surgical time of group B (31.48±6.15 min is significantly high as compared to group A (19.71±5.13 min with p<0.001. The regression analysis revealed that except surgery type, no other variable had significant impact on the duration of surgery. Postoperative symptoms are less in group A as compared to group B. Group B showed two recurrences whereas no recurrence was seen in group A. CONCLUSIONS Conjunctival autografting by patient’s own blood is better than 10-0 Nylon

  3. ISHTE deep-ocean corers and heater-implant system. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Olson, L. O.; Harrison, J. G.

    1982-09-01

    Seafloor instrumentation systems are being developed for the In-Situ Heat Transfer Experiment (ISHTE) to determine the thermal conductivity of deep ocean sediments. As part of the experiment, a heat canister will be implanted into the sediment. Also, after about one year on the seafloor, core samplers are to be actuated to gather sediment samples. This report describes the deep ocean piston corers and the heater-implant drive system.

  4. Three-Dimensional Implant Positioning with a Piezosurgery Implant Site Preparation Technique and an Intraoral Surgical Navigation System: Case Report.

    Science.gov (United States)

    Pellegrino, Gerardo; Taraschi, Valerio; Vercellotti, Tomaso; Ben-Nissan, Besim; Marchetti, Claudio

    This case report describes new implant site preparation techniques joining the benefits of using an intraoral navigation system to optimize three-dimensional implant site positioning in combination with an ultrasonic osteotomy. A report of five patients is presented, and the implant positions as planned in the navigation software with the postoperative scan image were compared. The preliminary results are useful, although further clinical studies with larger populations are needed to confirm these findings.

  5. Implant Surface Temperature Changes during Er:YAG Laser Irradiation with Different Cooling Systems.

    Directory of Open Access Journals (Sweden)

    Abbas Monzavi

    2014-04-01

    Full Text Available Peri-implantitis is one of the most common reasons for implant failure. Decontamination of infected implant surfaces can be achieved effectively by laser irradiation; although the associated thermal rise may cause irreversible bone damage and lead to implant loss. Temperature increments of over 10ºC during laser application may suffice for irreversible bone damage.The purpose of this study was to evaluate the temperature increment of implant surface during Er:YAG laser irradiation with different cooling systems.Three implants were placed in a resected block of sheep mandible and irradiated with Er:YAG laser with 3 different cooling systems namely water and air spray, air spray alone and no water or air spray. Temperature changes of the implant surface were monitored during laser irradiation with a K-type thermocouple at the apical area of the fixture.In all 3 groups, the maximum temperature rise was lower than 10°C. Temperature changes were significantly different with different cooling systems used (P<0.001.Based on the results, no thermal damage was observed during implant surface decontamination by Er:YAG laser with and without refrigeration. Thus, Er:YAG laser irradiation can be a safe method for treatment of periimplantitis.

  6. Clinical application of a tissue-cultured skin autograft: an alternative for the treatment of non-healing or slowly healing wounds?

    Science.gov (United States)

    Zöller, Nadja; Valesky, Eva; Butting, Manuel; Hofmann, Matthias; Kippenberger, Stefan; Bereiter-Hahn, Jürgen; Bernd, August; Kaufmann, Roland

    2014-01-01

    The treatment regime of non-healing or slowly healing wounds is constantly improving. One aspect is surgical defect coverage whereby mesh grafts and keratinocyte suspension are applied. Tissue-cultured skin autografts may be an alternative for the treatment of full-thickness wounds and wounds that cover large areas of the body surface. Autologous epidermal and dermal cells were isolated, expanded in vitro and seeded on collagen-elastin scaffolds. The developed autograft was immunohistochemically characterized and subsequently transplanted onto a facial chronic ulceration of a 71-year-old patient with vulnerable atrophic skin. Characterization of the skin equivalent revealed comparability to healthy human skin due to the epidermal strata, differentiation and proliferation markers. Within 138 days, the skin structure at the transplantation site closely correlated with the adjacent undisturbed skin. The present study demonstrates the comparability of the developed organotypic skin equivalent to healthy human skin and the versatility for clinical applications.

  7. Design of an end station for a high current ion implantation system

    International Nuclear Information System (INIS)

    Kranik, J.R.

    1979-01-01

    During the last 4 to 5 years IBM has been involved in an effort to develop a high current Ion Implantation system with pre-deposition capabilities. The system is dedicated to Arsenic implants, involving doses > 1 x 10 15 ions/cm 2 in the energy range of 30 to 60 keV. A major portion of this effort involved the design of an associated end station capable of producing high uniformity implants with beam currents in the 0.5 to 6.0 mA range. The end station contains all components from the exit of the analyzing magnet, including the exit beamline, process chamber, scan system, wafer handling system, high vacuum pumping package, beam optics, dosimetry system, and associated electronic controls. The unit was restricted to a six wafer (82 mm) batch size to maintain process line compatibility. In addition, implant dose non-uniformity objectives were established at +- 3% (2σ) within a wafer and +- 2% (2σ) wafer-to-wafer. Also, the system was to be capable of implanting 24 wafers/hour at a dose of 7.5 x 10 15 ions/cm 2 . Major consideration in the design was afforded to high reliability, ease of maintenance and production level throughput capabilities. The rationale and evolution of the final end station design is described. (author)

  8. Interfascicular suture with nerve autografts for median, ulnar and radial nerve lesions.

    Science.gov (United States)

    Pluchino, F; Luccarelli, G

    1981-05-01

    Interfascicular nerve suture with autografts is the operation of choice for repairing peripheral nerve injuries because it ensures more precise alignment of the fasciculi and so better chances of reinnervation of the sectioned nerve. The procedure as described by Millesi et al has been used at the Istituto Neurologico di Milano in 30 patients with traumatic lesions of the median, ulnar and radial nerves. All have been followed up for 2 to 7 years since operation. The results obtained are compared with those of other series obtained with interfascicular suture and with epineural suture. Microsurgery is essential. The best time to operate is discussed.

  9. Electroacoustic verification of frequency modulation systems in cochlear implant users.

    Science.gov (United States)

    Fidêncio, Vanessa Luisa Destro; Jacob, Regina Tangerino de Souza; Tanamati, Liége Franzini; Bucuvic, Érika Cristina; Moret, Adriane Lima Mortari

    2017-12-26

    The frequency modulation system is a device that helps to improve speech perception in noise and is considered the most beneficial approach to improve speech recognition in noise in cochlear implant users. According to guidelines, there is a need to perform a check before fitting the frequency modulation system. Although there are recommendations regarding the behavioral tests that should be performed at the fitting of the frequency modulation system to cochlear implant users, there are no published recommendations regarding the electroacoustic test that should be performed. Perform and determine the validity of an electroacoustic verification test for frequency modulation systems coupled to different cochlear implant speech processors. The sample included 40 participants between 5 and 18 year's users of four different models of speech processors. For the electroacoustic evaluation, we used the Audioscan Verifit device with the HA-1 coupler and the listening check devices corresponding to each speech processor model. In cases where the transparency was not achieved, a modification was made in the frequency modulation gain adjustment and we used the Brazilian version of the "Phrases in Noise Test" to evaluate the speech perception in competitive noise. It was observed that there was transparency between the frequency modulation system and the cochlear implant in 85% of the participants evaluated. After adjusting the gain of the frequency modulation receiver in the other participants, the devices showed transparency when the electroacoustic verification test was repeated. It was also observed that patients demonstrated better performance in speech perception in noise after a new adjustment, that is, in these cases; the electroacoustic transparency caused behavioral transparency. The electroacoustic evaluation protocol suggested was effective in evaluation of transparency between the frequency modulation system and the cochlear implant. Performing the adjustment of

  10. Clinical evaluation of a novel dental implant system as single implants under immediate loading conditions - 4-month post-loading results from a multicentre randomised controlled trial.

    Science.gov (United States)

    Esposito, Marco; Trullenque-Eriksson, Anna; Blasone, Rodolfo; Malaguti, Giuliano; Gaffuri, Cristiano; Caneva, Marco; Minciarelli, Armando; Luongo, Giuseppe

    To evaluate the safety and clinical effectiveness of a novel dental implant system (GENESIS Implant System, Keystone Dental, Massachusetts, USA) using another dental implant system by the same manufacturer as a control (PRIMA Implant System, Keystone Dental). A total of 53 patients requiring at least two single crowns had their sites randomised according to a split-mouth design to receive both implant systems at six centres. If implants could be placed with a torque superior to 40 Ncm they were to be loaded immediately with provisional crowns, otherwise after 3 months of submerged healing. Provisional crowns were replaced by definitive crowns 4 months after initial loading, when the follow-up period for the initial part of this study was completed. Outcome measures were crown/implant failures, complications, pink esthetic score (PES), peri-implant marginal bone level changes, plaque score, marginal bleeding, patients and preference of the clinician. In total 53 PRIMA and 53 GENESIS implants were placed. Three patients dropped out but all of the remaining patients were followed up to 4-months post-loading. No PRIMA implant failed whereas four GENESIS implants failed. Only two complications were reported for PRIMA implants. There were no statistically significant differences for crown/implant failures (difference in proportions = 0.080; P (McNemar test) = 0.125) and complications (difference in proportions = -0.04; P (McNemar test) = 0.500) between the implant systems. There were no differences at 4-months post-loading for plaque (difference = -0.54, 95% CI: -3.01 to 1.93; P (Paired t-test) = 0.660), marginal bleeding (difference = -3.8, 95% CI: -7.63 to 0.019; P (Paired t-test) = 0.051), PES (difference = 0.47, 95% CI: -0.56 to 1.50; P (Paired t-test) = 0.365) and marginal bone level changes (difference in mm = -0.04, 95% CI: -0.33 to 0.26; P (Paired t-test) = 0.795). The majority of the patients (46) had no

  11. Effects on cuytoskeleton system in pollen tube of pinus thunbergii induced by ion beam implantation

    International Nuclear Information System (INIS)

    Huang Qunce; Liang Qiuxia; Li Guopin

    2008-01-01

    The damage of the cytoskeleton system in the pollen and the pollen tube of Pinus thunbergii induced by ion beam implantation were researched. The results showed that the disorganization of the micro-tubules in the pollen tube was produced by N + implantation. The abnormal states of the pollen tube in morphology were very correlative with the abnormality of the cytoskeleton system. N + implantation was responsible for morphological abnormalities in the pollen tubes. There was a distinct correlation between the damage effects and the ion implantation dose. The add of dose caused more obvious damage effects. Furthermore, the state of the cytoskeleton system in the pollen tube was influenced by the ion implantation. The impact grade depended also on the ion implantation dose. (authors)

  12. Processing of microCT implant-bone systems images using Fuzzy Mathematical Morphology

    International Nuclear Information System (INIS)

    Bouchet, A; Pastore, J; Colabella, L; Omar, S; Ballarre, J

    2016-01-01

    The relationship between a metallic implant and the existing bone in a surgical permanent prosthesis is of great importance since the fixation and osseointegration of the system leads to the failure or success of the surgery. Micro Computed Tomography is a technique that helps to visualize the structure of the bone. In this study, the microCT is used to analyze implant-bone systems images. However, one of the problems presented in the reconstruction of these images is the effect of the iron based implants, with a halo or fluorescence scattering distorting the micro CT image and leading to bad 3D reconstructions. In this work we introduce an automatic method for eliminate the effect of AISI 316L iron materials in the implant-bone system based on the application of Compensatory Fuzzy Mathematical Morphology for future investigate about the structural and mechanical properties of bone and cancellous materials. (paper)

  13. A Wireless Implantable Switched-Capacitor Based Optogenetic Stimulating System

    Science.gov (United States)

    Lee, Hyung-Min; Kwon, Ki-Yong; Li, Wen

    2015-01-01

    This paper presents a power-efficient implantable optogenetic interface using a wireless switched-capacitor based stimulating (SCS) system. The SCS efficiently charges storage capacitors directly from an inductive link and periodically discharges them into an array of micro-LEDs, providing high instantaneous power without affecting wireless link and system supply voltage. A custom-designed computer interface in LabVIEW environment wirelessly controls stimulation parameters through the inductive link, and an optrode array enables simultaneous neural recording along with optical stimulation. The 4-channel SCS system prototype has been implemented in a 0.35-μm CMOS process and combined with the optrode array. In vivo experiments involving light-induced local field potentials verified the efficacy of the SCS system. An implantable version of the SCS system with flexible hermetic sealing is under development for chronic experiments. PMID:25570099

  14. Implantable electronics of a closed-loop system for controlling prosthetic hands

    Directory of Open Access Journals (Sweden)

    Nikas Antonios

    2017-09-01

    Full Text Available This paper presents the design of implantable electronics as a part of a system for prosthetic hand control. Purpose of the implant is the sensing of electrical signals originating from biological tissue and the actuation of the same, therefore closing the loop and allowing for an improved control of the prosthetic hand. The implant contains two integrated circuits for eight channel EMG monitoring and four channel stimulation, respectively. An on-board microcontroller allows for local pre-processing. All intracorporeal to extracorporeal communications are running through and are directed by the main processing platform. The external components of the control system include, in addition to the main processing and control platform, the inductive power transfer circuits and the pressure sensors for the sensory feedback. Different assembly and encapsulation options are taken into account for the implantable electronics and are unified in a single PCB design.

  15. The Ross II procedure: pulmonary autograft in the mitral position.

    Science.gov (United States)

    Athanasiou, Thanos; Cherian, Ashok; Ross, Donald

    2004-10-01

    The surgical management of mitral valve disease in women of childbearing age, young patients, and children with congenital mitral valve defects is made difficult by the prospect of lifelong anticoagulation. We suggest the use of a pulmonary autograft in the mitral position (Ross II procedure) as an alternative surgical technique. We present a review of the literature, historical perspectives, indications, selection criteria, and surgical technique for the Ross II procedure. Our literature search identified 14 studies that reported results from the Ross II operation. Performed in 103 patients, the overall in-hospital mortality was 7 (6.7%), with a late mortality of 10 (9%). Although further research is needed, current evidence suggests the Ross II operation is a valuable alternative in low-risk young patients where valve durability and the complication rate from other procedures is unsatisfactory and anticoagulation not ideal.

  16. Finite element analysis to compare complete denture and implant-retained overdentures with different attachment systems.

    Science.gov (United States)

    Barão, Valentim Adelino Ricardo; Assunção, Wirley Gonçalves; Tabata, Lucas Fernando; Delben, Juliana Aparecida; Gomes, Erica Alves; de Sousa, Edson Antonio Capello; Rocha, Eduardo Passos

    2009-07-01

    This finite element analysis compared stress distribution on complete dentures and implant-retained overdentures with different attachment systems. Four models of edentulous mandible were constructed: group A (control), complete denture; group B, overdenture retained by 2 splinted implants with bar-clip system; group C, overdenture retained by 2 unsplinted implants with o'ring system; and group D, overdenture retained by 2 splinted implants with bar-clip and 2 distally placed o'ring system. Evaluation was performed on Ansys software, with 100-N vertical load applied on central incisive teeth. The lowest maximum general stress value (in megapascal) was observed in group A (64.305) followed by groups C (119.006), D (258.650), and B (349.873). The same trend occurred in supporting tissues with the highest stress value for cortical bone. Unsplinted implants associated with the o'ring attachment system showed the lowest maximum stress values among all overdenture groups. Furthermore, o'ring system also improved stress distribution when associated with bar-clip system.

  17. The influence of micro and macro-geometry in term of bone-implant interface in two implant systems: an histomorphometrical study.

    Science.gov (United States)

    Rocci, A; Calcaterra, R; DI Girolamo, M; Rocci, M; Rocci, C; Baggi, L

    2015-01-01

    Many factors could affect the osseous healing of implants such as surface topography of biomaterial, the status of the bone/implant site, implant loading conditions, surgical technique and implant design. The aim of this study was to analyze the BIC of 2 different implants systems characterized by different micro and macrogeometry, that were placed in the posterior maxillary and mandibular jaws of humans, clinically unloaded and retrieved for histomorphometric analyses after 12 weeks. The patients were divided in two groups (Group I and II); group I was composed by 4 patients that each received in the posterior areas of mandible one type A implant [GTB-Plan1Health Amaro (UD) Italy] one type B implant (OsseoSpeed Astra Tech, Dentsply Molndal, Sweden). Group II was composed by 3 patients that each received in the posterior areas of jawsbone one type A implant [GTB-Plan1Health Amaro (UD) Italy] one type B implant (OsseoSpeed Astra Tech, Dentsply Molndal, Sweden). After 12 weeks of healing all the implants of both groups were harvested with the peri-implant bone tissues. Osseointegration process was evaluated throughout measurements of BIC. No statistical significance differences were found among the mean percentage of BIC of Group I - type A were 66,51% versus 49,96% in Group I - type B, as well as among the mean percentage of BIC of Group II - type A were 43.7% versus 60.02% in Group II - type B. Our results highlight that the mean percentage of BIC after 12 weeks from the implants placement without functional loading is not influenced by the composition of the implant surface.

  18. Influence of abutment materials on the implant-abutment joint stability in internal conical connection type implant systems.

    Science.gov (United States)

    Jo, Jae-Young; Yang, Dong-Seok; Huh, Jung-Bo; Heo, Jae-Chan; Yun, Mi-Jung; Jeong, Chang-Mo

    2014-12-01

    This study evaluated the influence of abutment materials on the stability of the implant-abutment joint in internal conical connection type implant systems. Internal conical connection type implants, cement-retained abutments, and tungsten carbide-coated abutment screws were used. The abutments were fabricated with commercially pure grade 3 titanium (group T3), commercially pure grade 4 titanium (group T4), or Ti-6Al-4V (group TA) (n=5, each). In order to assess the amount of settlement after abutment fixation, a 30-Ncm tightening torque was applied, then the change in length before and after tightening the abutment screw was measured, and the preload exerted was recorded. The compressive bending strength was measured under the ISO14801 conditions. In order to determine whether there were significant changes in settlement, preload, and compressive bending strength before and after abutment fixation depending on abutment materials, one-way ANOVA and Tukey's HSD post-hoc test was performed. Group TA exhibited the smallest mean change in the combined length of the implant and abutment before and after fixation, and no difference was observed between groups T3 and T4 (P>.05). Group TA exhibited the highest preload and compressive bending strength values, followed by T4, then T3 (Pabutment material can influence the stability of the interface in internal conical connection type implant systems. The strength of the abutment material was inversely correlated with settlement, and positively correlated with compressive bending strength. Preload was inversely proportional to the frictional coefficient of the abutment material.

  19. Architecture and control of a high current ion implanter system

    International Nuclear Information System (INIS)

    Bayer, E.H.; Paul, L.F.; Kranik, J.R.

    1979-01-01

    The design of an ion implant system for use in production requires that special attention be given to areas of design which normally are not emphasized on research or development type ion implanters. Manually operated, local controls are replaced by remote controls, automatic sequencing, and digital displays. For ease of maintenance and replication the individual components are designed as simply as possible and are contained in modules of separate identities, joined only by the beam line and electrical interconnections. A production environment also imposes requirements for the control of contamination and maintainability of clean room integrity. For that reason the major portion of the hardware is separated from the clean operator area and is housed in a maintenance core area. The controls of a production system should also be such that relatively unskilled technicians are able to operate the system with optimum repeatability and minimum operator intervention. An extensive interlock system is required. Most important, for use in production the ion implant system has to have a relatively high rate of throughput. Since the rate of throughput at a given dose is a function of beam current, pumpdown time and wafer handling capacity, design of components affecting these parameters has been optimized. Details of the system are given. (U.K.)

  20. The superiority of the autografts inactivated by high hydrostatic pressure to decellularized allografts in a porcine model.

    Science.gov (United States)

    Morimoto, Naoki; Mahara, Atsushi; Jinno, Chizuru; Ogawa, Mami; Kakudo, Natsuko; Suzuki, Shigehiko; Fujisato, Toshia; Kusumoto, Kenji; Yamaoka, Tetsuji

    2017-11-01

    We are developing a novel skin regeneration therapy in which the inactivation of nevus tissue via high hydrostatic pressure (HHP) is used in the reconstruction of the dermis in combination with a cultured epidermal autograft. In this study, we used a porcine skin graft model to explore whether autologous skin including cellular debris inactivated by HHP or allogeneic skin decellularized by HHP is better for dermal reconstruction. Grafts (n = 6) were prepared for five groups each: autologous skin without pressurization group (control group), autologous skin inactivated by 200 MPa group, autologous skin inactivated by 1000 MPa group, allogeneic skin decellularized by 200 MPa group, and allogeneic skin decellularized by 1000 MPa group. All of the grafts at 1, 4, and 12 weeks showed complete engraftment macroscopically. The mean areas of the grafts of the control group (p < 0.01) and autologous 200 MPa group (p < 0.01) were larger than that of the allogeneic 1000 MPa group at four weeks after implantation. The thickness of the control group and autologous 200 MPa group was comparable, and that of the autologous 200 MPa group was significantly thicker than that of the allogeneic 200 MPa group (p < 0.01). This suggests that the autologous dermis was superior to the allogeneic decellularized dermis as a skin graft, and that HHP at 200 MPa provided a better outcome than HHP at 1000 MPa. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2653-2661, 2017. © 2016 Wiley Periodicals, Inc.

  1. New orthopaedic implant management tool for computer-assisted planning, navigation, and simulation: from implant CAD files to a standardized XML-based implant database.

    Science.gov (United States)

    Sagbo, S; Blochaou, F; Langlotz, F; Vangenot, C; Nolte, L-P; Zheng, G

    2005-01-01

    Computer-Assisted Orthopaedic Surgery (CAOS) has made much progress over the last 10 years. Navigation systems have been recognized as important tools that help surgeons, and various such systems have been developed. A disadvantage of these systems is that they use non-standard formalisms and techniques. As a result, there are no standard concepts for implant and tool management or data formats to store information for use in 3D planning and navigation. We addressed these limitations and developed a practical and generic solution that offers benefits for surgeons, implant manufacturers, and CAS application developers. We developed a virtual implant database containing geometrical as well as calibration information for orthopedic implants and instruments, with a focus on trauma. This database has been successfully tested for various applications in the client/server mode. The implant information is not static, however, because manufacturers periodically revise their implants, resulting in the deletion of some implants and the introduction of new ones. Tracking these continuous changes and keeping CAS systems up to date is a tedious task if done manually. This leads to additional costs for system development, and some errors are inevitably generated due to the huge amount of information that has to be processed. To ease management with respect to implant life cycle, we developed a tool to assist end-users (surgeons, hospitals, CAS system providers, and implant manufacturers) in managing their implants. Our system can be used for pre-operative planning and intra-operative navigation, and also for any surgical simulation involving orthopedic implants. Currently, this tool allows addition of new implants, modification of existing ones, deletion of obsolete implants, export of a given implant, and also creation of backups. Our implant management system has been successfully tested in the laboratory with very promising results. It makes it possible to fill the current gap

  2. Total venous inflow occlusion and pericardial auto-graft reconstruction for right atrial hemangiosarcoma resection in a dog

    Science.gov (United States)

    Verbeke, Fei; Binst, Dominique; Stegen, Ludo; Waelbers, Tim; de Rooster, Hilde; Van Goethem, Bart

    2012-01-01

    A sizeable right atrial hemangiosarcoma in a 6-year-old Bordeaux dog, World Health Organization (WHO) stage 2, was excised using total venous inflow occlusion. The defect was restored with a non-vascularized pericardial auto-graft. The dog had a disease-free interval of 7 mo. The dog was euthanized 9 months later, at which time there were distant metastases but no indication of local recurrence. PMID:23543933

  3. Systemic assessment of patients undergoing dental implant surgeries: A trans- and post-operative analysis

    OpenAIRE

    Sanjay Byakodi; Sachin Kumar; Rajesh Kumar Reddy; Vipin Kumar; Shipra Sepolia; Shivangi Gupta; Harkanwal Preet Singh

    2017-01-01

    Background: Procedure-related and patient-related factors influence the prognosis of dental implants to a major extent. Hence, we aimed to evaluate and analyze various systemic factors in patients receiving dental implants. Materials and Methods: Fifty-one patients were included in the study, in which a total of 110 dental implants were placed. Complete examination of the subjects was done before and after placement of dental implants. Implant surgery was planned, and osseointegrated dental i...

  4. In Vitro Evaluation of Leakage at Implant-Abutment Connection of Three Implant Systems Having the Same Prosthetic Interface Using Rhodamine B

    Directory of Open Access Journals (Sweden)

    Antoine Berberi

    2014-01-01

    Full Text Available Objectives. Hollow space between implant and abutment may act as reservoir for commensal and/or pathogenic bacteria representing a potential source of tissue inflammation. Microbial colonization of the interfacial gap may ultimately lead to infection and bone resorption. Using Rhodamine B, a sensitive fluorescent tracer dye, we aim in this study to investigate leakage at implant-abutment connection of three implant systems having the same prosthetic interface. Materials and Methods. Twenty-one implants (seven Astra Tech, seven Euroteknika, and seven Dentium with the same prosthetic interface were connected to their original abutments, according to the manufacturers’ recommendation. After determination of the inner volume of each implant systems, the kinetic quantification of leakage was evaluated for each group using Rhodamine B (10−2 M. For each group, spectrophotometric analysis was performed to detect leakage with a fluorescence spectrophotometer at 1 h (T0 and 48 h (T1 of incubation time at room temperature. Results. Astra Tech had the highest inner volume (6.8 μL, compared to Dentium (4 μL and Euroteknika (2.9 μL. At T0 and T1, respectively, the leakage volume and percentage of each system were as follows: Astra Tech 0.043 μL or 1.48% (SD 0.0022, 0.08 μL or 5.56% (SD 0.0074, Euroteknika 0.09 μL or 6.93% (SD 0.0913, 0.21 μL or 20.55% (SD 0.0035, and Dentium 0.07 μL or 4.6% (SD 0.0029, 0.12 μL or 10.47% (SD 0.0072. Conclusion. The tested internal conical implant-abutment connections appear to be unable to prevent leakage. In average, Astra Tech implants showed the highest inner volume and the least leakage.

  5. Comparison of outcomes and safety of using hydroxyapatite granules as a substitute for autograft in cervical cages for anterior cervical discectomy and interbody fusion

    Directory of Open Access Journals (Sweden)

    Hosein Mashhadinezhad

    2014-03-01

    Full Text Available Background:   After cervical discectomy, autogenetic bone is packed into the cage to increase the rate of union between adjacent vertebral bodies, but donor site–related complications can still occur. In this study we evaluate the use   of hydroxyapatite granules as a substitute for autograft for interbody fusion.     Methods:   From November 2008 to November 2011, 236 patients participated in this study. Peek cages were packed with autologous bone grafts taken from the iliac crest in 112 patients and hydroxyapatite (HA granules in 124 patients.   Patients were followed for 12 months. The patients’ neurological signs, results, and complications were fully recorded   throughout the procedure. Radiological imaging was done to assess the fusion rate and settling ratio.     Results:   Formation of bony bridges at the third month was higher in the autograft group versus the granule group. However, there was no difference between both groups at the 12-month follow-up assessment. No difference (     P > 0.05   was found regarding improvement in neurological deficit as well as radicular pain and recovery rate between the two groups. Conclusions:   Interbody fusion cage containing HA granules proved to be an effective treatment for cervical spondylotic radiculopathy and/or myelopathy. Clinical and neurological outcome, radiographic measurement and fusion rate   in cage containing HA are similar and competitive with autograft packed cages.

  6. Systemic antibiotics and the risk of superinfection in peri-implantitis.

    Science.gov (United States)

    Verdugo, Fernando; Laksmana, Theresia; Uribarri, Agurne

    2016-04-01

    Peri-implantitis has emerged in the last few years as a complication difficult to resolve. The etiopathogenesis consensus is mainly attributed to bacteria. Following the preferred reporting items for systematic reviews and meta-analysis (PRISMA) guidelines, a PubMed/Medline literature search was performed using the US National Library of Medicine database up to 2015 to analyze available scientific data on the rationale and risk of superinfection associated to systemic antimicrobials in human peri-implant disease. A hand search was also conducted on relevant medical and microbiology journals. The methodological index for non-randomized studies (MINORS) was independently assessed for quality on the selected papers. Proposed combined therapies use broad-spectrum antibiotics to halt the disease progression. A major associated risk, particularly when prescribed empirically without microbiological follow-up, is the undetected development of superinfections and overgrowth of opportunistic pathogens difficult to eradicate. Peri-implant superinfections with opportunistic bacteria, yeast and viruses, are plausible risks associated to the use of systemic antibiotics in immunocompetent individuals. Lack of microbiological follow-up and antibiotic susceptibility testing may lead to ongoing microbial challenges that exacerbate the disease progression. The increased proliferation of antimicrobial resistance, modern implant surface topography and indiscriminative empiric antibiotic regimens may promote the escalation of peri-implant disease in years to come. A personalized 3-month supportive therapy may help prevent risks by sustaining a normal ecological balance, decreasing specific pathogen proportions and maintaining ideal plaque control. Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. Freeze-dried microarterial allografts

    International Nuclear Information System (INIS)

    Raman, J.; Hargrave, J.C.

    1990-01-01

    Rehydrated freeze-dried microarterial allografts were implanted to bridge arterial defects using New Zealand White rabbits as the experimental model. Segments of artery from the rabbit ear and thigh were harvested and preserved for a minimum of 2 weeks after freeze-drying. These allografts, approximately 1 mm in diameter and ranging from 1.5 to 2.5 cm in length, were rehydrated and then implanted in low-pressure and high-pressure arterial systems. Poor patency was noted in low-pressure systems in both allografts and autografts, tested in 12 rabbits. In the high-pressure arterial systems, allografts that were freeze-dried and reconstituted failed in a group of 10 rabbits with an 8-week patency rate of 30 percent. Gamma irradiation in an effort to reduce infection and antigenicity of grafts after freeze-drying was associated with a patency rate of 10 percent at 8 weeks in this system in another group of 10 rabbits. Postoperative cyclosporin A therapy was associated with a patency rate of 22.2 percent in the high-pressure arterial system in a 9-rabbit group. Control autografts in this system in a group of 10 rabbits showed a 100 percent patency at 8 weeks. Microarterial grafts depend on perfusion pressure of the vascular bed for long-term patency. Rehydrated freeze-dried microarterial allografts do not seem to function well in lengths of 1 to 2.5 cm when implanted in a high-pressure arterial system. Freeze-dried arterial allografts are probably not antigenic

  8. Clinical and radiological outcomes after a quasi-anatomical reconstruction of medial patellofemoral ligament with gracilis tendon autograft.

    Science.gov (United States)

    Monllau, Joan C; Masferrer-Pino, Àngel; Ginovart, Gerard; Pérez-Prieto, Daniel; Gelber, Pablo E; Sanchis-Alfonso, Vicente

    2017-08-01

    To analyse the clinical and radiological outcomes of a quasi-anatomical reconstruction of the medial patellofemoral ligament (MPFL) with a gracilis tendon autograft. Patients with objective recurrent patellar instability that were operated on from 2006 to 2012 were included. A quasi-anatomical surgical technique was performed using a gracilis tendon autograft. It was anatomically attached at the patella, and the adductor magnus tendon was also used as a pulley for femoral fixation (non-anatomical reconstruction). The IKDC, Kujala and Lysholm scores as well as Tegner and VAS for pain were collected preoperatively and at final follow-up. Radiographic measurements of patellar position tilt and signs of osteoarthritis (OA) as well as trochlear dysplasia were also recorded. Thirty-six patients were included. The mean age at surgery was 25.6 years. After a minimum 27 months of follow-up, all functional scores significantly improved (p patellofemoral surfaces at the short term, as shown by the absence of radiological signs of OA in the CT scan. The procedure has been shown to be safe and suitable for the treatment of chronic patellar instability, including in adolescents with open physis. A new effective, inexpensive and easy-to-perform technique is described to reconstruct MPFL in the daily clinical practice. Therapeutic case series, Level IV.

  9. Implantes de hidroxiapatita em falhas ósseas produzidas no fêmur de ratos submetidos ao tabagismo passivo Hydroxyapatite implants in bone defects produced in rat femurs submitted to passive tobacco exposure

    Directory of Open Access Journals (Sweden)

    Thiago Cerizza Pinheiro

    2008-10-01

    menores quando comparados com os do grupo controle. CONCLUSÃO: A neoformação óssea em defeitos do esqueleto pode ocorrer naturalmente em animais submetidos ao tabagismo passivo, no entanto, de forma mais lenta e em menor proporção.INTRODUCTION: Defects with bone mass loss are frequently treated with bone autografts. Endografts of bones using biomaterials, such as hydroxyapatite (HA also have been used for the same purpose, replacing autografts. However, bone tissue health conditions are basic for osteointegration of the implant. Thus, excessive tobacco consumption, either as an active or as a passive smoker, may harm the process of bone neoformation with a hydroxyapatite implant due to its deleterious effects to bone tissue. OBJECTIVE: To evaluate the nutritional status of the animals and the process of bone neoformation when porous hydroxyapatite granules are implanted in bone defects of the femur of rats submitted to passive tobacco exposure. METHOD: Porous hydroxyapatite granules were implanted in bone defects produced in the left distal femoral epiphysis of rats subjected to prolonged passive tobacco exposure. The animals were followed along the treatment of tobacco exposure during six months, to evaluate their physical conditions. After eight weeks of the bone implant with the biomaterial, the animals were sacrificed and the specimens of the implant region were submitted to routine histological testing, and maintained in paraffin blocks for morphometric histological and radiological analysis. RESULTS: The mass variation of the experimental group was found to be more intense than that of the control group. As to radiological findings, the control group had an apparent more radio lucent and organized image. In the morphological analysis, there was a better closing of the bone defect and osteointegration of hydroxyapatite in the control group. Upon comparing the volume of bone formed in the receiving area of the femur between the control and the experimental group

  10. Successful correction of tibial bone deformity through multiple surgical procedures, liquid nitrogen-pretreated bone tumor autograft, three-dimensional external fixation, and internal fixation in a patient with primary osteosarcoma: a case report.

    Science.gov (United States)

    Takeuchi, Akihiko; Yamamoto, Norio; Shirai, Toshiharu; Nishida, Hideji; Hayashi, Katsuhiro; Watanabe, Koji; Miwa, Shinji; Tsuchiya, Hiroyuki

    2015-12-07

    In a previous report, we described a method of reconstruction using tumor-bearing autograft treated by liquid nitrogen for malignant bone tumor. Here we present the first case of bone deformity correction following a tumor-bearing frozen autograft via three-dimensional computerized reconstruction after multiple surgeries. A 16-year-old female student presented with pain in the left lower leg and was diagnosed with a low-grade central tibial osteosarcoma. Surgical bone reconstruction was performed using a tumor-bearing frozen autograft. Bone union was achieved at 7 months after the first surgical procedure. However, local tumor recurrence and lung metastases occurred 2 years later, at which time a second surgical procedure was performed. Five years later, the patient developed a 19° varus deformity and underwent a third surgical procedure, during which an osteotomy was performed using the Taylor Spatial Frame three-dimensional external fixation technique. A fourth corrective surgical procedure was performed in which internal fixation was achieved with a locking plate. Two years later, and 10 years after the initial diagnosis of tibial osteosarcoma, the bone deformity was completely corrected, and the patient's limb function was good. We present the first report in which a bone deformity due to a primary osteosarcoma was corrected using a tumor-bearing frozen autograft, followed by multiple corrective surgical procedures that included osteotomy, three-dimensional external fixation, and internal fixation.

  11. The study of the use of a latex biomembrane and conjunctival autograft in rabbit conjunctiva wound healing.

    Science.gov (United States)

    Pinho, Erika Christina Canarim Martha de; Chahud, Fernando; Lachat, João-José; Coutinho-Netto, Joaquim José; Sousa, Sidney Julio Faria E

    2018-04-01

    RESUMO Objetivo: Estudar o uso da biomembrana de látex e o transplante conjuntival autólogo na cicatrização conjuntival em coelhos. Métodos: Em nove coelhos albinos, neo-zelandeses, machos foram removidas áreas retangulares idênticas, do quadrante supero nasal, adjacente ao limbo, de ambos os olhos. As áreas desnudas da camada esclerótica nos olhos direitos foram recobertas com biomembrana de látex e a dos olhos esquerdos com enxerto conjuntival autólogo. Os animais foram sacrificados em grupos de três, aos 7, 14 e 21 dias após a cirurgia. Os tecidos do local cirúrgico, incluindo a córnea, foram fixados em formaldeído, antes de serem processados em parafina e corados com hematoxilina e eosina. A natureza e a intensidade da resposta inflamatória e o padrão de epitelização da superfície conjuntival foram avaliados sob microscopia óptica, em seções histológicas longitudinais, passando pelo centro dos espécimes anatômicos. Resultados: Até o décimo quarto dia pós-operatório, o grupo que recebeu a biomembrana apresentou reação inflamatória mais intensa do que o grupo com auto enxerto conjuntival. Aos 14 dias, os olhos com biomembrana apresentavam-se menos inflamados e com estroma mais espesso do que aos 7 dias. Aos 21 dias, a reparação conjuntival de ambos os grupos apresentavam características semelhantes. Conclusão: Apesar de apresentar uma cicatrização mais lenta, a biomembrana de látex se mostrou tão eficaz quanto o auto enxerto conjuntival na reconstrução da superfície ocular após três semanas de cicatrização pós-operatória. Devido as suas baixas toxicidade e alergenicidade, este material parece ser uma opção terapêutica promissora na reconstrução da conjuntiva.ABSTRACT Purpose: To study a latex biomembrane and conjunctival autograft with regard to the promotion of conjunctival healing in rabbits. The study included nine male albino rabbits. In these rabbits, a rectangular area of the conjunctiva was surgically

  12. [Study on preparation of laser micropore porcine acellular dermal matrix combined with split-thickness autograft and its application in wound transplantation].

    Science.gov (United States)

    Liang, Li-Ming; Chai, Ji-Ke; Yang, Hong-Ming; Feng, Rui; Yin, Hui-Nan; Li, Feng-Yu; Sun, Qiang

    2007-04-01

    To prepare a porcine acellular dermal matrix (PADM), and to optimize the interpore distance between PADM and co-grafted split-thickness autologous skin. Porcine skin was treated with trypsin/Triton X-100 to prepare an acellular dermal matrix. Micropores were produced on the PADM with a laser punch. The distance between micropores varied as 0.8 mm, 1.0 mm, 1.2 mm and 1.5 mm. Full-thickness defect wounds were created on the back of 144 SD rats. The rats were randomly divided into 6 groups as follows, with 24 rats in each group. Micropore groups I -IV: the wounds were grafted with PADM with micropores in four different intervals respectively, and covered with split-thickness autologous skin graft. Mesh group: the wounds were grafted with meshed PADM and split-thickness autograft. with simple split-thickness autografting. The gross observation of wound healing and histological observation were performed at 2, 4, 6 weeks after surgery. The wound healing rate and contraction rate were calculated. Two and four weeks after surgery, the wound healing rate in micropore groups I and II was lower than that in control group (P micropore groups I , II and mesh group (P > 0.05) until 6 weeks after grafting( P micropore groups I and II ([(16.0 +/- 2.6)%, (15.1 +/- 2.4)%] was remarkably lower than that in control group 4 and 6 weeks after grafting (P micropore PADM (0.8 mm or 1.0 mm in distance) grafting in combination with split-thickness autografting can improve the quality of wound healing. PADM with laser micropores in 1.0 mm distance is the best choice among them.

  13. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    Directory of Open Access Journals (Sweden)

    Stefan Landgraeber

    2014-01-01

    Full Text Available All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older people (>75 yrs of total joint replacement revision surgery. In some people implant debris (particles and ions from metals can influence the adaptive immune system as well, giving rise to the concept of metal sensitivity. However, a consensus of studies agrees that the dominant form of this response is due to innate reactivity by macrophages to implant debris where both danger (DAMP and pathogen (PAMP signalling elicit cytokine-based inflammatory responses. This paper discusses implant debris induced release of the cytokines and chemokines due to activation of the innate (and the adaptive immune system and the subsequent formation of osteolysis. Different mechanisms of implant-debris reactivity related to the innate immune system are detailed, for example, danger signalling (e.g., IL-1β, IL-18, IL-33, etc., toll-like receptor activation (e.g., IL-6, TNF-α, etc., apoptosis (e.g., caspases 3–9, bone catabolism (e.g., TRAP5b, and hypoxia responses (Hif1-α. Cytokine-based clinical and basic science studies are in progress to provide diagnosis and therapeutic intervention strategies.

  14. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    Science.gov (United States)

    Landgraeber, Stefan; Jäger, Marcus; Jacobs, Joshua J.; Hallab, Nadim James

    2014-01-01

    All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older people (>75 yrs) of total joint replacement revision surgery. In some people implant debris (particles and ions from metals) can influence the adaptive immune system as well, giving rise to the concept of metal sensitivity. However, a consensus of studies agrees that the dominant form of this response is due to innate reactivity by macrophages to implant debris where both danger (DAMP) and pathogen (PAMP) signalling elicit cytokine-based inflammatory responses. This paper discusses implant debris induced release of the cytokines and chemokines due to activation of the innate (and the adaptive) immune system and the subsequent formation of osteolysis. Different mechanisms of implant-debris reactivity related to the innate immune system are detailed, for example, danger signalling (e.g., IL-1β, IL-18, IL-33, etc.), toll-like receptor activation (e.g., IL-6, TNF-α, etc.), apoptosis (e.g., caspases 3–9), bone catabolism (e.g., TRAP5b), and hypoxia responses (Hif1-α). Cytokine-based clinical and basic science studies are in progress to provide diagnosis and therapeutic intervention strategies. PMID:24891761

  15. Long-term Evaluation of the Ross Procedure in Acute Infective Endocarditis.

    Science.gov (United States)

    Ratschiller, Thomas; Sames-Dolzer, Eva; Paulus, Patrick; Schimetta, Wolfgang; Müller, Hannes; Zierer, Andreas F; Mair, Rudolf

    2017-10-05

    Optimal valve substitute for young patients with aortic valve endocarditis remains controversial. Given its better resistance to infection, the Ross procedure is an attractive alternative to prosthetic valve replacement or homograft implantation. The objective of this study was to assess long-term outcomes of the Ross procedure in this indication. From January 1991 to April 2017, 190 patients underwent a Ross procedure at our institution. Acute endocarditis was the indication for operation in 19 patients, including 6 patients with a bicuspid aortic valve. The pulmonary autograft was implanted as freestanding root replacement in all patients. The clinical follow-up is 100% complete, with a mean of 12.0 ± 5.7 years. The mean age of the study population was 35.9 ± 11.5 years. Moderate or severe aortic regurgitation was present in 84.2% of the patients. Systemic embolization had occurred in 36.8% of the patients. The mean aortic cross-clamp time was 126 ± 24 minutes. The median length of stay on the intensive care unit was 1 day. Mortality at 30 days was 5.3% (1 patient with gastrointestinal bleeding). Echocardiography at hospital discharge documented no or trivial aortic regurgitation in all patients. No case of recurrent endocarditis affecting the autograft occurred. One patient (0.4% per patient-year) was reoperated 1.8 years after the Ross procedure for homograft endocarditis. Three patients (15.8%) were reoperated for autograft aneurysm. The Ross procedure is a safe and effective alternative to prosthetic valve replacement or homograft implantation in selected young patients with acute endocarditis with a low rate of recurrent infection. Copyright © 2017 Elsevier Inc. All rights reserved.

  16. The Failure Envelope Concept Applied To The Bone-Dental Implant System.

    Science.gov (United States)

    Korabi, R; Shemtov-Yona, K; Dorogoy, A; Rittel, D

    2017-05-17

    Dental implants interact with the jawbone through their common interface. While the implant is an inert structure, the jawbone is a living one that reacts to mechanical stimuli. Setting aside mechanical failure considerations of the implant, the bone is the main component to be addressed. With most failure criteria being expressed in terms of stress or strain values, their fulfillment can mean structural flow or fracture. However, in addition to those effects, the bony structure is likely to react biologically to the applied loads by dissolution or remodeling, so that additional (strain-based) criteria must be taken into account. While the literature abounds in studies of particular loading configurations, e.g. angle and value of the applied load to the implant, a general study of the admissible implant loads is still missing. This paper introduces the concept of failure envelopes for the dental implant-jawbone system, thereby defining admissible combinations of vertical and lateral loads for various failure criteria of the jawbone. Those envelopes are compared in terms of conservatism, thereby providing a systematic comparison of the various failure criteria and their determination of the admissible loads.

  17. Comparison of outcomes and safety of using hydroxyapatite granules as a substitute for autograft in cervical cages for anterior cervical discectomy and interbody fusion

    Directory of Open Access Journals (Sweden)

    Hosein Mashhadinezhad

    2014-03-01

    Full Text Available Background:   After cervical discectomy, autogenetic bone is packed into the cage to increase the rate of union between adjacent vertebral bodies, but donor site–related complications can still occur. In this study we evaluate the use   of hydroxyapatite granules as a substitute for autograft for interbody fusion.     Methods:   From November 2008 to November 2011, 236 patients participated in this study. Peek cages were packed with autologous bone grafts taken from the iliac crest in 112 patients and hydroxyapatite (HA granules in 124 patients.   Patients were followed for 12 months. The patients’ neurological signs, results, and complications were fully recorded   throughout the procedure. Radiological imaging was done to assess the fusion rate and settling ratio.     Results:   Formation of bony bridges at the third month was higher in the autograft group versus the granule group. However, there was no difference between both groups at the 12-month follow-up assessment. No difference (     P > 0.05   was found regarding improvement in neurological deficit as well as radicular pain and recovery rate between the two groups. Conclusions:   Interbody fusion cage containing HA granules proved to be an effective treatment for cervical spondylotic radiculopathy and/or myelopathy. Clinical and neurological outcome, radiographic measurement and fusion rate   in cage containing HA are similar and competitive with autograft packed cages.    

  18. Accuracy of a digital impression system based on parallel confocal laser technology for implants with consideration of operator experience and implant angulation and depth.

    Science.gov (United States)

    Giménez, Beatriz; Özcan, Mutlu; Martínez-Rus, Francisco; Pradíes, Guillermo

    2014-01-01

    To evaluate the accuracy of a digital impression system based on parallel confocal red laser technology, taking into consideration clinical parameters such as operator experience and angulation and depth of implants. A maxillary master model with six implants (located bilaterally in the second molar, second premolar, and lateral incisor positions) was fitted with six polyether ether ketone scan bodies. One second premolar implant was placed with 30 degrees of mesial angulation; the opposite implant was positioned with 30 degrees of distal angulation. The lateral incisor implants were placed 2 or 4 mm subgingivally. Two experienced and two inexperienced operators performed intraoral scanning. Five different interimplant distances were then measured. The files obtained from the scans were imported with reverse-engineering software. Measurements were then made with a coordinate measurement machine, with values from the master model used as reference values. The deviations from the actual values were then calculated. The differences between experienced and inexperienced operators and the effects of different implant angulations and depths were compared statistically. Overall, operator 3 obtained significantly less accurate results. The angulated implants did not significantly influence accuracy compared to the parallel implants. Differences were found in the amount of error in the different quadrants. The second scanned quadrant had significantly worse results than the first scanned quadrant. Impressions of the implants placed at the tissue level were less accurate than implants placed 2 and 4 mm subgingivally. The operator affected the accuracy of measurements, but the performance of the operator was not necessarily dependent on experience. Angulated implants did not decrease the accuracy of the digital impression system tested. The scanned distance affected the predictability of the accuracy of the scanner, and the error increased with the increased length of the

  19. Particulated articular cartilage: CAIS and DeNovo NT.

    Science.gov (United States)

    Farr, Jack; Cole, Brian J; Sherman, Seth; Karas, Vasili

    2012-03-01

    Cartilage Autograft Implantation System (CAIS; DePuy/Mitek, Raynham, MA) and DeNovo Natural Tissue (NT; ISTO, St. Louis, MO) are novel treatment options for focal articular cartilage defects in the knee. These methods involve the implantation of particulated articular cartilage from either autograft or juvenile allograft donor, respectively. In the laboratory and in animal models, both CAIS and DeNovo NT have demonstrated the ability of the transplanted cartilage cells to "escape" from the extracellular matrix, migrate, multiply, and form a new hyaline-like cartilage tissue matrix that integrates with the surrounding host tissue. In clinical practice, the technique for both CAIS and DeNovo NT is straightforward, requiring only a single surgery to affect cartilage repair. Clinical experience is limited, with short-term studies demonstrating both procedures to be safe, feasible, and effective, with improvements in subjective patient scores, and with magnetic resonance imaging evidence of good defect fill. While these treatment options appear promising, prospective randomized controlled studies are necessary to refine the indications and contraindications for both CAIS and DeNovo NT.

  20. Implementation and validation of an implant-based coordinate system for RSA migration calculation.

    Science.gov (United States)

    Laende, Elise K; Deluzio, Kevin J; Hennigar, Allan W; Dunbar, Michael J

    2009-10-16

    An in vitro radiostereometric analysis (RSA) phantom study of a total knee replacement was carried out to evaluate the effect of implementing two new modifications to the conventional RSA procedure: (i) adding a landmark of the tibial component as an implant marker and (ii) defining an implant-based coordinate system constructed from implant landmarks for the calculation of migration results. The motivation for these two modifications were (i) to improve the representation of the implant by the markers by including the stem tip marker which increases the marker distribution (ii) to recover clinical RSA study cases with insufficient numbers of markers visible in the implant polyethylene and (iii) to eliminate errors in migration calculations due to misalignment of the anatomical axes with the RSA global coordinate system. The translational and rotational phantom studies showed no loss of accuracy with the two new measurement methods. The RSA system employing these methods has a precision of better than 0.05 mm for translations and 0.03 degrees for rotations, and an accuracy of 0.05 mm for translations and 0.15 degrees for rotations. These results indicate that the new methods to improve the interpretability, relevance, and standardization of the results do not compromise precision and accuracy, and are suitable for application to clinical data.

  1. Successful fifth metatarsal bulk autograft reconstruction of thermal necrosis post intramedullary fixation.

    Science.gov (United States)

    Veljkovic, Andrea; Le, Vu; Escudero, Mario; Salat, Peter; Wing, Kevin; Penner, Murray; Younger, Alastair

    2018-03-21

    Reamed intramedullary (IM) screw fixation for proximal fifth metatarsal fractures is technically challenging with potentially devastating complications if basic principles are not followed. A case of an iatrogenic fourth-degree burn after elective reamed IM screw fixation of a proximal fifth metatarsal fracture in a high-level athlete is reported. The case was complicated by postoperative osteomyelitis with third-degree soft-tissue defect. This was successfully treated with staged autologous bone graft reconstruction, tendon reconstruction, and local bi-pedicle flap coverage. The patient returned to competitive-level sports, avoiding the need for fifth ray amputation. Critical points of the IM screw technique and definitive reconstruction are discussed. Bulk autograft reconstruction is a safe and effective alternative to ray amputation in segmental defects of the fifth metatarsal.Level of evidence V.

  2. Electrophysiology Catheter-Facilitated coronary sinus cannulation and implantation of cardiac resynchronization therapy systems

    Directory of Open Access Journals (Sweden)

    Antonis S. Manolis, MD, FESC, FACC, FHRS

    2018-01-01

    Full Text Available Background: Cardiac resynchronization therapy (CRT device implantation is hampered by difficult placement of the left ventricular (LV lead. We have routinely used a steerable electrophysiology catheter to guide coronary sinus (CS cannulation and facilitate LV lead positioning. The aim of this prospective study is to present our results with this approach in 138 consecutive patients receiving a CRT device over 10 years. Methods: The study included 120 men and 18 women, aged 64.8±11.4 years, with coronary disease (n=63, cardiomyopathy (n=72, or other disease (n=3, and mean ejection fraction of 24.5±4.5%. Devices were implanted for refractory heart failure and dyssynchrony, all but 2 in the presence of left bundle branch block. Implanted devices included biventricular pacemakers (CRT-P (n=33 and cardioverter defibrillators (CRT-D (n=105. Results: Using the electrophysiology catheter, the CS could be engaged in 134 (97.1% patients. In 4 patients failing CS cannulation, a dual-chamber device was implanted in 2, and bifocal right ventricular pacing was effected in 2. Bifocal (n=2 or conventional (n=1 systems were implanted in another 3 patients, in whom the LV lead got dislodged (n=2 or removed because of local dissection (n=1. Thus, finally, a CRT system was successfully established in 131 (94.9% patients. There were 3 patients with CS dissection, of whom 1 was complicated by cardiac tamponade managed with pericardiocentesis. There were no perioperative deaths. During follow-up (31.0±21.2 months, clinical improvement was reported by 108 (82.4% patients. Conclusion: Routine use of an electrophysiology catheter greatly facilitated CS cannulation and successful LV lead placement in ∼95% of patients undergoing CRT system implantation. Keywords: heart failure, cardiac resynchronization therapy, implantable cardioverter defibrillator, coronary sinus, left ventricular lead

  3. Bioelectric analyses of an osseointegrated intelligent implant design system for amputees.

    Science.gov (United States)

    Isaacson, Brad M; Stinstra, Jeroen G; MacLeod, Rob S; Webster, Joseph B; Beck, James P; Bloebaum, Roy D

    2009-07-15

    The projected number of American amputees is expected to rise to 3.6 million by 2050. Many of these individuals depend on artificial limbs to perform routine activities, but prosthetic suspensions using traditional socket technology can prove to be cumbersome and uncomfortable for a person with limb loss. Moreover, for those with high proximal amputations, limited residual limb length may prevent exoprosthesis attachment all together. Osseointegrated implant technology is a novel operative procedure which allows firm skeletal attachment between the host bone and an implant. Preliminary results in European amputees with osseointegrated implants have shown improved clinical outcomes by allowing direct transfer of loads to the bone-implant interface. Despite the apparent advantages of osseointegration over socket technology, the current rehabilitation procedures require long periods of restrictive load bearing prior which may be reduced with expedited skeletal attachment via electrical stimulation. The goal of the osseointegrated intelligent implant design (OIID) system is to make the implant part of an electrical system to accelerate skeletal attachment and help prevent periprosthetic infection. To determine optimal electrode size and placement, we initiated proof of concept with computational modeling of the electric fields and current densities that arise during electrical stimulation of amputee residual limbs. In order to provide insure patient safety, subjects with retrospective computed tomography scans were selected and three dimensional reconstructions were created using customized software programs to ensure anatomical accuracy (Seg3D and SCIRun) in an IRB and HIPAA approved study. These software packages supported the development of patient specific models and allowed for interactive manipulation of electrode position and size. Preliminary results indicate that electric fields and current densities can be generated at the implant interface to achieve the

  4. Accuracy of various impression materials and methods for two implant systems: An effect size study.

    Science.gov (United States)

    Schmidt, Alexander; Häussling, Teresa; Rehmann, Peter; Schaaf, Heidrun; Wöstmann, Bernd

    2018-04-01

    An accurate impression is required for implant treatment. The aim of this in-vitro study was to determine the effect size of the impression material/method, implant system and implant angulation on impression transfer precision. An upper jaw model with three BEGO and three Straumann implants (angulations 0°, 15°, 20°) in the left and right maxilla was used as a reference model. One polyether (Impregum Penta) and two polyvinyl siloxanes (Flexitime Monophase/Aquasil Ultra Monophase) were examined with two impression techniques (open and closed tray). A total of 60 impressions were made. A coordinate measurement machine was used to measure the target variables for 3D-shift, implant axis inclination and implant axis rotation. All the data were subjected to a four-way ANOVA. The effect size (partial eta-squared [η 2 P ]) was reported. The impression material had a significant influence on the 3D shift and the implant axis inclination deviation (p-values=.000), and both factors had very large effect sizes (3D-shift [η 2 P ]=.599; implant axis inclination [η 2 P ]=.298). Impressions made with polyvinyl siloxane exhibited the highest transfer precision. When the angulation of the implants was larger, more deviations occurred for the implant axis rotational deviation. The implant systems and impression methods showed partially significant variations (p-values=.001-.639) but only very small effect sizes (η 2 P =.001-.031). The impression material had the greatest effect size on accuracy in terms of the 3D shift and the implant axis inclination. For multiunit restorations with disparallel implants, polyvinyl siloxane materials should be considered. In addition, the effect size of a multivariate investigation should be reported. Copyright © 2017 Japan Prosthodontic Society. Published by Elsevier Ltd. All rights reserved.

  5. Impact of pregnancy on autograft dilatation and aortic valve function following the Ross procedure.

    Science.gov (United States)

    Carvajal, Horacio G; Lindley, Kathryn J; Shah, Trupti; Brar, Anoop K; Barger, Philip M; Billadello, Joseph J; Eghtesady, Pirooz

    2018-03-01

    The effects of pregnancy on autograft dilatation and neoaortic valve function in patients with a Ross procedure have not been studied. We sought to evaluate the effect of pregnancy on autograft dilatation and valve function in these patients with the goal of determining whether pregnancy is safe after the Ross procedure. A retrospective chart review of female patients who underwent a Ross procedure was conducted. Medical records for 51 patients were reviewed. Among the 33 patients who met inclusion criteria, 11 became pregnant after surgery and 22 did not. Echocardiographic reports were used to record aortic root diameter and aortic insufficiency before, during, and after pregnancy. Patient's charts were reviewed for reinterventions and complications. Primary endpoints included reinterventions, aortic root dilation of ≥5 cm, aortic insufficiency degree ≥ moderate, and death. There were 18 pregnancies carried beyond 20 weeks in 11 patients. There was no significant difference in aortic root diameter between nulliparous patients and parous patients prior to their first pregnancy (3.53 ± 0.44 vs 3.57 ± 0.69 cm, P = .74). There was no significant change in aortic root diameter after first pregnancy (3.7 ± 0.4 cm, P = .056) although there was significant dilatation after the second (4.3 ± 0.7 cm, P = .009) and third (4.5 ± 0.7 cm, P = .009) pregnancies. Freedom from combined endpoints was significantly higher for patients in the pregnancy group than those in the nonpregnancy group (P = .002). Pregnancy was not associated with significantly increased adverse events in patients following the Ross procedure. Special care should be taken after the first pregnancy, as multiparity may lead to increased neoaortic dilatation. © 2017 Wiley Periodicals, Inc.

  6. Recent progress in the development of Terumo implantable left ventricular assist system.

    Science.gov (United States)

    Nojiri, C; Kijima, T; Maekawa, J; Horiuchi, K; Kido, T; Sugiyama, T; Mori, T; Sugiura, N; Asada, T; Shimane, H; Ozaki, T; Suzuki, M; Akamatsu, T; Akutsu, T

    1999-01-01

    The research group of the Terumo Corporation, the NTN Corporation, and Setsunan University (T. Akamatsu) has been developing an implantable left ventricular assist system (ILVAS) featuring a centrifugal blood pump with a magnetically suspended impeller (MSCP). The impeller of the MSCP is suspended by a magnetic bearing, providing contact-free rotation of the impeller inside the pump housing. Thus the MSCP is expected to provide years of long-term durability. Ex vivo chronic sheep experiments using the extracorporeal model (Model I) demonstrated long-term durability, nonthrombogenicity, and a low hemolysis rate (plasma free Hb model (Model II; 196 ml, 400 g) was evaluated ex vivo in 2 sheep and intrathoracically implanted in a small sheep (45 kg). These experiments were terminated at 70, 79, and 17 days, respectively, because of blood leakage through the connector system within the housing of Model II. There was no thrombus formation on the retrieved pump surfaces. A new connector system was introduced to the Model II pump (modified Model II), and the pump was intrathoracically implanted in a sheep. Pump flow rate was maintained at 3-7 L/min at 1700-1800 rpm. The temperature elevation on the surfaces of the motor and the electromagnet inside the pump casing was kept less than 6 degrees C. The temperature of the tissue adjacent to the pump casing became normal 10 days postoperatively. The sheep survived for more than 5 months without any sign of mechanical failure or thromboembolic complication. In vitro real-time endurance tests of motor bearings made of stainless steel and silicone nitride have been conducted for more than 1 year without any sign of bearing wear. The next prototype system (Model III), with an implantable controller and a new MSCP with reduced input power, has been developed with a view toward a totally implantable LVAS.

  7. Ultrasound guided implantation of chest port systems via the lateral subclavian vein

    International Nuclear Information System (INIS)

    Zaehringer, M.; Hilgers, J.; Krueger, K.; Strohe, D.; Bangard, C.; Neumann, L.; Lackner, K.; Warm, M.; Reiser, M.; Toex, U.

    2006-01-01

    Purpose: Retrospective analysis of the success and complication rates of chest port implantation via the lateral subclavian vein. Materials and methods: Between January 2003 and June 2004, the lateral subclavian vein in 271 patients (186 women, 85 men, mean age 53.2 years) was punctured guided by ultrasound. This access was used to insert a port system, and the catheter tip was placed at the cavoatrial junction. The port reservoir was implanted in a subcutaneous infraclavicular pocket and fixed to the fascia of the pectoralis muscle. Indications for port implantation were chemotherapy (n=239), total parenteral nutrition (n=2) and intravenous medication (n=30). The patient follow-up was mainly performed either by the oncology division of the department of gynecology or by the department of internal medicine. Results: A chest port catheter system was successfully implanted in all patients. The catheter remained in place for a mean duration of 269.4 days (SD 192.3 days). No complications occurred during implantation. In the post-interventional period, 6 catheter dysfunctions were found (thrombotic 0.09 per 1000 catheter days; mechanic 0.05 per 1000 catheter days). While one local infection occurred in the early post-interventional period, 3 local and 15 systemic infections were independent of the port catheter placement (0.39 per 1000 catheter days). The rate of port catheter explantations due to dysfunction or infection was 0.07 per 1000 catheter days. Conclusion: Ultrasound-guided puncture of the lateral subclavian vein is a safe procedure for the insertion of central venous port catheter systems and had a very low complication rate in our study. For further evaluation of our port placement technique, prospective studies compared to placement through the internal jugular vein are necessary. (orig.)

  8. Mutual-Information-Based Incremental Relaying Communications for Wireless Biomedical Implant Systems

    Directory of Open Access Journals (Sweden)

    Yangzhe Liao

    2018-02-01

    Full Text Available Network lifetime maximization of wireless biomedical implant systems is one of the major research challenges of wireless body area networks (WBANs. In this paper, a mutual information (MI-based incremental relaying communication protocol is presented where several on-body relay nodes and one coordinator are attached to the clothes of a patient. Firstly, a comprehensive analysis of a system model is investigated in terms of channel path loss, energy consumption, and the outage probability from the network perspective. Secondly, only when the MI value becomes smaller than the predetermined threshold is data transmission allowed. The communication path selection can be either from the implanted sensor to the on-body relay then forwards to the coordinator or from the implanted sensor to the coordinator directly, depending on the communication distance. Moreover, mathematical models of quality of service (QoS metrics are derived along with the related subjective functions. The results show that the MI-based incremental relaying technique achieves better performance in comparison to our previous proposed protocol techniques regarding several selected performance metrics. The outcome of this paper can be applied to intra-body continuous physiological signal monitoring, artificial biofeedback-oriented WBANs, and telemedicine system design.

  9. Approaches and Challenges of Engineering Implantable Microelectromechanical Systems (MEMS Drug Delivery Systems for in Vitro and in Vivo Applications

    Directory of Open Access Journals (Sweden)

    Ken-Tye Yong

    2012-11-01

    Full Text Available Despite the advancements made in drug delivery systems over the years, many challenges remain in drug delivery systems for treating chronic diseases at the personalized medicine level. The current urgent need is to develop novel strategies for targeted therapy of chronic diseases. Due to their unique properties, microelectromechanical systems (MEMS technology has been recently engineered as implantable drug delivery systems for disease therapy. This review examines the challenges faced in implementing implantable MEMS drug delivery systems in vivo and the solutions available to overcome these challenges.

  10. The Syed temporary interstitial iridium gynaecological implant: an inverse planning system

    International Nuclear Information System (INIS)

    Fung, Albert Y.C.

    2002-01-01

    Patients with advanced gynaecological cancer are often treated with a temporary interstitial implant using the Syed template and Ir-192 ribbons at the Memorial Sloan-Kettering Cancer Center. Urgency in planning is great. We created a computerized inverse planning system for the Syed temporary gynaecological implant, which optimized the ribbon strengths a few seconds after catheter digitization. Inverse planning was achieved with simulated annealing. We discovered that hand-drawn target volumes had drawbacks; hence instead of producing a grid of points based on target volume, the optimization points were generated directly from the catheter positions without requiring an explicit target volume. Since all seeds in the same ribbon had the same strength, the minimum doses were located at both ends of the implant. Optimization points generated at both ends ensured coverage of the whole implant. Inverse planning took only a few seconds, and generated plans that provide a good starting point for manual improvement. (author)

  11. A Comparison of Clinical Outcomes with Regular- and Low-Profile Totally Implanted Central Venous Port Systems

    International Nuclear Information System (INIS)

    Teichgraeber, Ulf Karl-Martin; Steitparth, Florian; Cho, Chie Hee; Benter, Thomas; Gebauer, Bernhard

    2009-01-01

    The purpose of this study was to evaluate whether low-profile totally implanted central venous port systems can reduce the late complication of skin perforation. Forty patients (age, 57 ± 13 years; 22 females, 18 males) were randomized for the implantation of a low-profile port system, and another 40 patients (age, 61 ± 14 years; 24 females, 16 males) received a regular port system as control group. Indications for port catheter implantation were malignant disease requiring chemotherapy. All port implantations were performed in the angiography suite using sonographically guided central venous puncture and fluoroscopic guidance of the catheter placement. Procedure time, number of complications (procedure-related immediate, early, and late complications), and number of explantations were assessed. Follow-up was performed for 6 months. All port implantations were successfully completed in both study groups. There were two incidents of skin perforation observed in the control group. One skin perforation occurred 13 weeks and the other 16 weeks after port implantation (incidence, 5%) in patients with regular-profile port systems. Two infections were observed, one port infection in each study group. Both infections were characterized as catheter-related infections (infection rate: 0.15 catheter-related infections per 1000 catheter days). In conclusion, low-profile port systems can be placed as safely as traditional chest ports and reduce the risk of developing skin perforations, which occurs when the port system is too tight within the port pocket.

  12. Patient satisfaction and dissatisfaction with mandibular two-implant overdentures using different attachment systems: 5-year outcomes.

    Science.gov (United States)

    Al-Zubeidi, Mohammed I; Alsabeeha, Nabeel H M; Thomson, W Murray; Payne, Alan G T

    2012-10-01

    Different attachment systems for mandibular two-implant overdentures could influence levels of patient satisfaction. Positive consensus of the majority of patients being satisfied does not preclude the possibility of dissatisfaction for some. To evaluate patient satisfaction and dissatisfaction before and after 5 years of wearing mandibular two implant overdentures using different attachment systems ; to determine the prognostic relevance of pretreatment complete denture complaints to treatment outcomes. A total of 106 edentulous participants enrolled in a clinical trial completed a preliminary self-report inventory of their original complete denture complaints.New complete maxillary dentures and mandibular two-implant overdentures were provided to each participant using one of six different attachment systems. Patient satisfaction was determined at pretreatment; at baseline with mandibular two-implant overdenture insertion; and then annually for 5 years, using visual analogue and Likert-type scales. Patient satisfaction with mandibular two-implant overdentures showed significant changes pre- to posttreatment(baseline) in all domains, but these were significant immediately and maintained without further significance for 5 years, other than pain with the overdenture. After 5 years, no significant differences were observed with all the attachment systems. Highly significant differences were found with some social and psychological aspects by the fifth year compared to baseline. Diagnostic and prognostic indicators from a pretreatment inventory identified 12 participants (13.5%) who were dissatisfied. These indicators revealed a maladaptive predisposition to mandibular two-implant overdentures. The provision of mandibular two-implant overdentures will, in the majority of patients, significantly enhance levels of patient satisfaction for 5 years, as compared to complete mandibular dentures, regardless of the attachment system. Careful evaluation of pretreatment

  13. Bandwidth Efficient Overlapped FSK Coded Secure Command Transmission for Medical Implant Communication Systems

    Directory of Open Access Journals (Sweden)

    Selman KULAÇ

    2018-06-01

    Full Text Available Nowadays, wireless communication systems are exploited in most health care systems. Implantable Medical Systems (IMS also have wireless communication capability. However, it is very important that secure wireless communication should be provided in terms of both patient rights and patient health. Therefore, wireless transmission systems of IMS should also be robust against to eavesdroppers and adversaries. In this study, a specific overlapped and coded frequency shift keying (FSK modulation technique is developed and security containing with low complexity is provided by this proposed technique. The developed method is suitable for wireless implantable medical systems since it provides low complexity and security as well as bandwidth efficiency.

  14. Effect of topical autologous platelet-rich fibrin versus no intervention on epithelialization of donor sites and meshed split-thickness skin autografts: a randomized clinical trial

    DEFF Research Database (Denmark)

    Danielsen, P.; Jorgensen, B.; Jorgensen, L.N.

    2008-01-01

    BACKGROUND: Autologous platelet-rich fibrin contains multiple growth factors. The aim of this randomized clinical trial was to study the effect of topical platelet-rich fibrin on epithelialization of donor sites and meshed split-thickness skin autografts. METHODS: Twenty consecutive leg ulcer pat...

  15. 3-Coil resonance-based wireless power transfer system for implantable electronic

    KAUST Repository

    Yi, Ying; Buttner, Ulrich; Fan, Yiqiang; Foulds, Ian G.

    2013-01-01

    This paper presents a 3-coil resonance-based wireless power transfer (R-WPT) system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. A theoretical analysis and experimental measurements in terms of quality factor Q and power transfer efficiency (PTE), was done. Our proposed 3-coil scheme can achieve a high PTE with a resonance frequency of 2.46 MHz over a transfer distance of up to 30 mm, by using two 15-mm radius implant coils. The achieved experimental PTE is more than 85%at a 5 mm separation distance, and about 50% PTE at a distance of 20 mm. © 2013 IEEE.

  16. 3-Coil resonance-based wireless power transfer system for implantable electronic

    KAUST Repository

    Yi, Ying

    2013-05-01

    This paper presents a 3-coil resonance-based wireless power transfer (R-WPT) system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. A theoretical analysis and experimental measurements in terms of quality factor Q and power transfer efficiency (PTE), was done. Our proposed 3-coil scheme can achieve a high PTE with a resonance frequency of 2.46 MHz over a transfer distance of up to 30 mm, by using two 15-mm radius implant coils. The achieved experimental PTE is more than 85%at a 5 mm separation distance, and about 50% PTE at a distance of 20 mm. © 2013 IEEE.

  17. Comparative evaluation of the effectiveness of the implantation in the lateral part of the mandible between short tissue level (TE) and bone level (BL) implant systems.

    Science.gov (United States)

    Hadzik, Jakub; Botzenhart, Ute; Krawiec, Maciej; Gedrange, Tomasz; Heinemann, Friedhelm; Vegh, Andras; Dominiak, Marzena

    2017-09-01

    Short dental implants can be an alternative method of treatment to a vertical bone augmentation procedure at sites of reduced alveolar height. However, for successful treatment, an implant system that causes a minimal marginal bone loss (MBL) should be taken into consideration. The aim of the study has been to evaluate implantation effectiveness for bone level and tissue level short implants provided in lateral aspects of partially edentulous mandible and limited alveolar ridge height. The MBL and primary as well as secondary implant stability were determined in the study. Patients were randomly divided into two groups according to the method of treatment provided. Sixteen short Bone Level Implants (OsseoSpeed TX, Astra tech) and 16 short Tissue Level Implants (RN SLActive ® , Straumann) were successfully placed in the edentulous part of the mandible. The determination of the marginal bone level was based on radiographic evaluation after 12 and 36 weeks. Implant stability was measured immediately after insertion and after 12 weeks. The marginal bone level of Bone Level Implants was significantly lower compared to Tissue Level Implants. Furthermore, the Bone Level Implants had greater primary and secondary stability in comparison with Tissue Level Implants (Primary: 77.8 ISQ versus 66.5 ISQ; Secondary: 78.9 ISQ versus 73.9 ISQ, respectively). Since short Bone Level Implants showed a significantly decreased MBL 12 and 36 weeks after implantation as well as better results for the primary stability compared to Tissue Level Implants, they should preferentially be used for this mentioned indication. Copyright © 2017 Elsevier GmbH. All rights reserved.

  18. Retention systems for extraoral maxillofacial prosthetic implants: a critical review.

    Science.gov (United States)

    Cobein, M V; Coto, N P; Crivello Junior, O; Lemos, J B D; Vieira, L M; Pimentel, M L; Byrne, H J; Dias, R B

    2017-10-01

    We describe the techniques available for retention of implant-supported prostheses: bar-clips, O-rings, and magnets. We present reported preferences and, although this is limited by the heterogeneity of methods used and patients studied, we hope we have identified the best retention systems for maxillofacial prosthetic implants. If practitioners know the advantages and disadvantages of each system, they can choose the most natural and comfortable prosthesis. We searched the PubMed and Scopus databases, and restricted our search to papers published 2001-13. MeSH terms used were Maxillofacial prosthesis and Craniofacial prosthesis OR Craniofacial prostheses. We found a total of 2630 papers, and after duplicates had been removed we analysed the rest and found 25 papers for review. Of these, 12 were excluded because they were case reports or non-systematic reviews. Of the remaining 13, 10 described group analyses and seemed appropriate to find practitioner's choices, as cited in the abstract (n=1611 prostheses). Three papers did not mention the type of prosthetic connection used, so were excluded. The most popular choices for different conditions were analysed, though the sites and retention systems were not specified in all 10 papers. The bar-clip system was the most used in auricular (6/10 papers) and nasal prostheses (4/10). For the orbital region, 6/10 favoured magnets. Non-osseointegrated mechanical or adhesive retention techniques are the least expensive and have no contraindications. When osseointegrated implants are possible, each facial region has a favoured system. The choice of system is influenced by two factors: standard practice and the abilities of the maxillofacial surgeon and maxillofacial prosthetist. Copyright © 2017 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  19. Intraoperative implant rod three-dimensional geometry measured by dual camera system during scoliosis surgery.

    Science.gov (United States)

    Salmingo, Remel Alingalan; Tadano, Shigeru; Abe, Yuichiro; Ito, Manabu

    2016-05-12

    Treatment for severe scoliosis is usually attained when the scoliotic spine is deformed and fixed by implant rods. Investigation of the intraoperative changes of implant rod shape in three-dimensions is necessary to understand the biomechanics of scoliosis correction, establish consensus of the treatment, and achieve the optimal outcome. The objective of this study was to measure the intraoperative three-dimensional geometry and deformation of implant rod during scoliosis corrective surgery.A pair of images was obtained intraoperatively by the dual camera system before rotation and after rotation of rods during scoliosis surgery. The three-dimensional implant rod geometry before implantation was measured directly by the surgeon and after surgery using a CT scanner. The images of rods were reconstructed in three-dimensions using quintic polynomial functions. The implant rod deformation was evaluated using the angle between the two three-dimensional tangent vectors measured at the ends of the implant rod.The implant rods at the concave side were significantly deformed during surgery. The highest rod deformation was found after the rotation of rods. The implant curvature regained after the surgical treatment.Careful intraoperative rod maneuver is important to achieve a safe clinical outcome because the intraoperative forces could be higher than the postoperative forces. Continuous scoliosis correction was observed as indicated by the regain of the implant rod curvature after surgery.

  20. Age at implantation and auditory memory in cochlear implanted children.

    Science.gov (United States)

    Mikic, B; Miric, D; Nikolic-Mikic, M; Ostojic, S; Asanovic, M

    2014-05-01

    Early cochlear implantation, before the age of 3 years, provides the best outcome regarding listening, speech, cognition an memory due to maximal central nervous system plasticity. Intensive postoperative training improves not only auditory performance and language, but affects auditory memory as well. The aim of this study was to discover if the age at implantation affects auditory memory function in cochlear implanted children. A total of 50 cochlear implanted children aged 4 to 8 years were enrolled in this study: early implanted (1-3y) n = 27 and late implanted (4-6y) n = 23. Two types of memory tests were used: Immediate Verbal Memory Test and Forward and Backward Digit Span Test. Early implanted children performed better on both verbal and numeric tasks of auditory memory. The difference was statistically significant, especially on the complex tasks. Early cochlear implantation, before the age of 3 years, significantly improve auditory memory and contribute to better cognitive and education outcomes.

  1. Ultrasound guided implantation of chest port systems via the lateral subclavian vein; Die sonographisch gezielte Implantation von Portkathetersystemen ueber die laterale Vena subclavia

    Energy Technology Data Exchange (ETDEWEB)

    Zaehringer, M.; Hilgers, J.; Krueger, K.; Strohe, D.; Bangard, C.; Neumann, L.; Lackner, K. [Inst. fuer Radiologische Diagnostik, Univ. zu Koeln (Germany); Warm, M. [Gynaekologie, Univ. zu Koeln (Germany); Reiser, M. [Medizinische Klinik I, Univ. zu Koeln (Germany); Toex, U. [Medizinische Klinik IV, Univ. zu Koeln (Germany)

    2006-03-15

    Purpose: Retrospective analysis of the success and complication rates of chest port implantation via the lateral subclavian vein. Materials and methods: Between January 2003 and June 2004, the lateral subclavian vein in 271 patients (186 women, 85 men, mean age 53.2 years) was punctured guided by ultrasound. This access was used to insert a port system, and the catheter tip was placed at the cavoatrial junction. The port reservoir was implanted in a subcutaneous infraclavicular pocket and fixed to the fascia of the pectoralis muscle. Indications for port implantation were chemotherapy (n=239), total parenteral nutrition (n=2) and intravenous medication (n=30). The patient follow-up was mainly performed either by the oncology division of the department of gynecology or by the department of internal medicine. Results: A chest port catheter system was successfully implanted in all patients. The catheter remained in place for a mean duration of 269.4 days (SD 192.3 days). No complications occurred during implantation. In the post-interventional period, 6 catheter dysfunctions were found (thrombotic 0.09 per 1000 catheter days; mechanic 0.05 per 1000 catheter days). While one local infection occurred in the early post-interventional period, 3 local and 15 systemic infections were independent of the port catheter placement (0.39 per 1000 catheter days). The rate of port catheter explantations due to dysfunction or infection was 0.07 per 1000 catheter days. Conclusion: Ultrasound-guided puncture of the lateral subclavian vein is a safe procedure for the insertion of central venous port catheter systems and had a very low complication rate in our study. For further evaluation of our port placement technique, prospective studies compared to placement through the internal jugular vein are necessary. (orig.)

  2. Biomaterials with Antibacterial and Osteoinductive Properties to Repair Infected Bone Defects

    OpenAIRE

    Lu, Haiping; Liu, Yi; Guo, Jing; Wu, Huiling; Wang, Jingxiao; Wu, Gang

    2016-01-01

    The repair of infected bone defects is still challenging in the fields of orthopedics, oral implantology and maxillofacial surgery. In these cases, the self-healing capacity of bone tissue can be significantly compromised by the large size of bone defects and the potential/active bacterial activity. Infected bone defects are conventionally treated by a systemic/local administration of antibiotics to control infection and a subsequent implantation of bone grafts, such as autografts and allogra...

  3. An Implantable Wireless Neural Interface System for Simultaneous Recording and Stimulation of Peripheral Nerve with a Single Cuff Electrode.

    Science.gov (United States)

    Shon, Ahnsei; Chu, Jun-Uk; Jung, Jiuk; Kim, Hyungmin; Youn, Inchan

    2017-12-21

    Recently, implantable devices have become widely used in neural prostheses because they eliminate endemic drawbacks of conventional percutaneous neural interface systems. However, there are still several issues to be considered: low-efficiency wireless power transmission; wireless data communication over restricted operating distance with high power consumption; and limited functionality, working either as a neural signal recorder or as a stimulator. To overcome these issues, we suggest a novel implantable wireless neural interface system for simultaneous neural signal recording and stimulation using a single cuff electrode. By using widely available commercial off-the-shelf (COTS) components, an easily reconfigurable implantable wireless neural interface system was implemented into one compact module. The implantable device includes a wireless power consortium (WPC)-compliant power transmission circuit, a medical implant communication service (MICS)-band-based radio link and a cuff-electrode path controller for simultaneous neural signal recording and stimulation. During in vivo experiments with rabbit models, the implantable device successfully recorded and stimulated the tibial and peroneal nerves while communicating with the external device. The proposed system can be modified for various implantable medical devices, especially such as closed-loop control based implantable neural prostheses requiring neural signal recording and stimulation at the same time.

  4. An Implantable Wireless Neural Interface System for Simultaneous Recording and Stimulation of Peripheral Nerve with a Single Cuff Electrode

    Directory of Open Access Journals (Sweden)

    Ahnsei Shon

    2017-12-01

    Full Text Available Recently, implantable devices have become widely used in neural prostheses because they eliminate endemic drawbacks of conventional percutaneous neural interface systems. However, there are still several issues to be considered: low-efficiency wireless power transmission; wireless data communication over restricted operating distance with high power consumption; and limited functionality, working either as a neural signal recorder or as a stimulator. To overcome these issues, we suggest a novel implantable wireless neural interface system for simultaneous neural signal recording and stimulation using a single cuff electrode. By using widely available commercial off-the-shelf (COTS components, an easily reconfigurable implantable wireless neural interface system was implemented into one compact module. The implantable device includes a wireless power consortium (WPC-compliant power transmission circuit, a medical implant communication service (MICS-band-based radio link and a cuff-electrode path controller for simultaneous neural signal recording and stimulation. During in vivo experiments with rabbit models, the implantable device successfully recorded and stimulated the tibial and peroneal nerves while communicating with the external device. The proposed system can be modified for various implantable medical devices, especially such as closed-loop control based implantable neural prostheses requiring neural signal recording and stimulation at the same time.

  5. Systemic Assessment of Patients Undergoing Dental Implant Surgeries: A Trans- and Post-operative Analysis.

    Science.gov (United States)

    Byakodi, Sanjay; Kumar, Sachin; Reddy, Rajesh Kumar; Kumar, Vipin; Sepolia, Shipra; Gupta, Shivangi; Singh, Harkanwal Preet

    2017-01-01

    Procedure-related and patient-related factors influence the prognosis of dental implants to a major extent. Hence, we aimed to evaluate and analyze various systemic factors in patients receiving dental implants. Fifty-one patients were included in the study, in which a total of 110 dental implants were placed. Complete examination of the subjects was done before and after placement of dental implants. Implant surgery was planned, and osseointegrated dental implants were placed in the subjects. Postoperative evaluation of the dental implant patients was done after 3 weeks. Anxiety levels were determined using State-Trait Anxiety Inventory (STAI) questionnaire on the surgery day and after 1 week of surgery. The participant describes how they feel at the moment by responding to twenty items as follows: (1) absolutely not, (2) slightly, (3) somewhat, or (4) very much. All the results were recorded and statistical analyzed by SPSS software. Out of 51, 29 patients were males while 22 were females, with ratio of 1.32:1. Female patients' mean age was 50.18 years while male patients' mean age was 52.71 years, with statistically nonsignificant difference between them. Functional rehabilitation was the main purpose of choosing dental implants in more than 90% of the subjects. Diameter of 3.75 mm was the shortest implants to be placed in the present study, whereas in terms of length, 8.5 mm was the shortest length of dental implant used in the present study. Tooth area in which maximum implants were placed in our study was 36 tooth region. Maximum implants were placed in Type II bone quality ( n = 38). Implants installed in the mandible were clamped more efficiently than implants placed in the maxilla ( P < 0.001). The difference of average STAI-State subscore before and after the surgery was statistically significant ( P < 0.05; significant). Mandibular dental implants show more clamping (torque) than maxillary dental implants.

  6. Systemic assessment of patients undergoing dental implant surgeries: A trans- and post-operative analysis

    Directory of Open Access Journals (Sweden)

    Sanjay Byakodi

    2017-01-01

    Full Text Available Background: Procedure-related and patient-related factors influence the prognosis of dental implants to a major extent. Hence, we aimed to evaluate and analyze various systemic factors in patients receiving dental implants. Materials and Methods: Fifty-one patients were included in the study, in which a total of 110 dental implants were placed. Complete examination of the subjects was done before and after placement of dental implants. Implant surgery was planned, and osseointegrated dental implants were placed in the subjects. Postoperative evaluation of the dental implant patients was done after 3 weeks. Anxiety levels were determined using State-Trait Anxiety Inventory (STAI questionnaire on the surgery day and after 1 week of surgery. The participant describes how they feel at the moment by responding to twenty items as follows: (1 absolutely not, (2 slightly, (3 somewhat, or (4 very much. All the results were recorded and statistical analyzed by SPSS software. Results: Out of 51, 29 patients were males while 22 were females, with ratio of 1.32:1. Female patients' mean age was 50.18 years while male patients' mean age was 52.71 years, with statistically nonsignificant difference between them. Functional rehabilitation was the main purpose of choosing dental implants in more than 90% of the subjects. Diameter of 3.75 mm was the shortest implants to be placed in the present study, whereas in terms of length, 8.5 mm was the shortest length of dental implant used in the present study. Tooth area in which maximum implants were placed in our study was 36 tooth region. Maximum implants were placed in Type II bone quality (n = 38. Implants installed in the mandible were clamped more efficiently than implants placed in the maxilla (P < 0.001. The difference of average STAI-State subscore before and after the surgery was statistically significant (P < 0.05; significant. Conclusion: Mandibular dental implants show more clamping (torque than maxillary

  7. Anatomic Double-Bundle Anterior Cruciate Ligament Reconstruction With a Free Quadriceps Tendon Autograft.

    Science.gov (United States)

    Caterev, Sergiu; Nistor, Dan Viorel; Todor, Adrian

    2016-10-01

    Anatomic double-bundle anterior cruciate ligament (ACL) reconstruction aims to restore the 2 functional bundles of the ACL in an attempt to better reproduce the native biomechanics of the injured knee and promote long-term knee health. However, this concept is not fully accepted and is not performed on a standard basis. In addition, the superiority of this technique over the conventional single-bundle technique has been questioned, especially the long-term clinical results. One of the down sides of the double-bundle reconstruction is the complexity of the procedure, with increased risks, operative time, and costs compared with the single-bundle procedure. Also, the revision procedure, if necessary, is more challenging. We propose a technique that has some advantages over the traditional double-bundle procedure, using a single femoral tunnel, 2 tibial tunnels, and a free quadriceps tendon autograft.

  8. Bone regeneration by the osteoconductivity of porous titanium implants manufactured by selective laser melting: a histological and micro computed tomography study in the rabbit.

    Science.gov (United States)

    de Wild, Michael; Schumacher, Ralf; Mayer, Kyrill; Schkommodau, Erik; Thoma, Daniel; Bredell, Marius; Kruse Gujer, Astrid; Grätz, Klaus W; Weber, Franz E

    2013-12-01

    The treatment of large bone defects still poses a major challenge in orthopaedic and cranio-maxillofacial surgery. One possible solution could be the development of personalized porous titanium-based implants that are designed to meet all mechanical needs with a minimum amount of titanium and maximum osteopromotive properties so that it could be combined with growth factor-loaded hydrogels or cell constructs to realize advanced bone tissue engineering strategies. Such implants could prove useful for mandibular reconstruction, spinal fusion, the treatment of extended long bone defects, or to fill in gaps created on autograft harvesting. The aim of this study was to determine the mechanical properties and potential of bone formation of light weight implants generated by selective laser melting (SLM). We mainly focused on osteoconduction, as this is a key feature in bone healing and could serve as a back-up for osteoinduction and cell transplantation strategies. To that end, defined implants were produced by SLM, and their surfaces were left untreated, sandblasted, or sandblasted/acid etched. In vivo bone formation with the different implants was tested throughout calvarial defects in rabbits and compared with untreated defects. Analysis by micro computed tomography (μCT) and histomorphometry revealed that all generatively produced porous Ti structures were well osseointegrated into the surrounding bone. The histomorphometric analysis revealed that bone formation was significantly increased in all implant-treated groups compared with untreated defects and significantly increased in sand blasted implants compared with untreated ones. Bone bridging was significantly increased in sand blasted acid-etched scaffolds. Therefore, scaffolds manufactured by SLM should be surface treated. Bone augmentation beyond the original bone margins was only seen in implant-treated defects, indicating an osteoconductive potential of the implants that could be utilized clinically for bone

  9. The KineSpring® Knee Implant System: an implantable joint-unloading prosthesis for treatment of medial knee osteoarthritis

    Directory of Open Access Journals (Sweden)

    Clifford AG

    2013-05-01

    Full Text Available Anton G Clifford,1 Stefan M Gabriel,1 Mary O’Connell,1 David Lowe,1 Larry E Miller,2,3 Jon E Block31Moximed, Inc, Hayward, CA, USA; 2Miller Scientific Consulting, Inc, Arden, NC, USA; 3The Jon Block Group, San Francisco, CA, USAAbstract: Symptomatic medial compartment knee osteoarthritis (OA is the leading cause of musculoskeletal pain and disability in adults. Therapies intended to unload the medial knee compartment have yielded unsatisfactory results due to low patient compliance with conservative treatments and high complication rates with surgical options. There is no widely available joint-unloading treatment for medial knee OA that offers clinically important symptom alleviation, low complication risk, and high patient acceptance. The KineSpring® Knee Implant System (Moximed, Inc, Hayward, CA, USA is a first-of-its-kind, implantable, extra-articular, extra-capsular prosthesis intended to alleviate knee OA-related symptoms by reducing medial knee compartment loading while overcoming the limitations of traditional joint-unloading therapies. Preclinical and clinical studies have demonstrated excellent prosthesis durability, substantial reductions in medial compartment and total joint loads, and clinically important improvements in OA-related pain and function. The purpose of this report is to describe the KineSpring System, including implant characteristics, principles of operation, indications for use, patient selection criteria, surgical technique, postoperative care, preclinical testing, and clinical experience. The KineSpring System has potential to bridge the gap between ineffective conservative treatments and irreversible surgical interventions for medial compartment knee OA.Keywords: KineSpring, knee, medial, osteoarthritis, prosthesis

  10. A wireless power transmission system for implantable devices in freely moving rodents.

    Science.gov (United States)

    Eom, Kyungsik; Jeong, Joonsoo; Lee, Tae Hyung; Kim, Jinhyung; Kim, Junghoon; Lee, Sung Eun; Kim, Sung June

    2014-08-01

    Reliable wireless power delivery for implantable devices in animals is highly desired for safe and effective experimental use. Batteries require frequent replacement; wired connections are inconvenient and unsafe, and short-distance inductive coupling requires the attachment of an exterior transmitter to the animal's body. In this article, we propose a solution by which animals with implantable devices can move freely without attachments. Power is transmitted using coils attached to the animal's cage and is received by a receiver coil implanted in the animal. For a three-dimensionally uniform delivery of power, we designed a columnar dual-transmitter coil configuration. A resonator-based inductive link was adopted for efficient long-range power delivery, and we used a novel biocompatible liquid crystal polymer substrate as the implantable receiver device. Using this wireless power delivery system, we obtain an average power transfer efficiency of 15.2% (minimum efficiency of 10% and a standard deviation of 2.6) within a cage of 15×20×15 cm3.

  11. Anterior-Posterior Instability of the Knee Following ACL Reconstruction with Bone-Patellar Tendon-Bone Ligament in Comparison with Four-Strand Hamstrings Autograft

    Directory of Open Access Journals (Sweden)

    A. G. Angoules

    2013-01-01

    Full Text Available Purpose. To evaluate anterior-posterior knee laxity using two different autografts. Material-Methods. 40 patients, (34 males and 6 women, 17–54 years old (mean: 31, were included in the present study. Group A (4SHS = 20 underwent reconstruction using four-strand hamstrings, and group B (BPBT = 20 underwent reconstruction using bone-patellar tendon-bone autograft. Using the KT-1000 arthrometer, knee instability was calculated in both knees of all patients preoperatively and 3, 6, and 12 months after surgery at the ACL-operated knee. The contralateral healthy knee was used as an internal control group. Results. Anterior-posterior instability using the KT1000 Arthrometer was found to be increased after ACL insufficiency. The recorded laxity improved after arthroscopic ACL reconstruction in both groups. However, statistically significant greater values were detected in the bone-patellar tendon-bone group, which revealed reduction of anteroposterior stability values to an extent, where no statistical significance with the normal values even after 3 months after surgery was observed. Conclusions. Anterior-Posterior instability of the knee improved significantly after arthroscopic ACL reconstruction. The bone-patellar tendon-bone graft provided an obvious greater stability.

  12. Survival of dental implants placed in sites of previously failed implants.

    Science.gov (United States)

    Chrcanovic, Bruno R; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

    2017-11-01

    To assess the survival of dental implants placed in sites of previously failed implants and to explore the possible factors that might affect the outcome of this reimplantation procedure. Patients that had failed dental implants, which were replaced with the same implant type at the same site, were included. Descriptive statistics were used to describe the patients and implants; survival analysis was also performed. The effect of systemic, environmental, and local factors on the survival of the reoperated implants was evaluated. 175 of 10,096 implants in 98 patients were replaced by another implant at the same location (159, 14, and 2 implants at second, third, and fourth surgeries, respectively). Newly replaced implants were generally of similar diameter but of shorter length compared to the previously placed fixtures. A statistically significant greater percentage of lost implants were placed in sites with low bone quantity. There was a statistically significant difference (P = 0.032) in the survival rates between implants that were inserted for the first time (94%) and implants that replaced the ones lost (73%). There was a statistically higher failure rate of the reoperated implants for patients taking antidepressants and antithrombotic agents. Dental implants replacing failed implants had lower survival rates than the rates reported for the previous attempts of implant placement. It is suggested that a site-specific negative effect may possibly be associated with this phenomenon, as well as the intake of antidepressants and antithrombotic agents. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. An image guidance system for positioning robotic cochlear implant insertion tools

    Science.gov (United States)

    Bruns, Trevor L.; Webster, Robert J.

    2017-03-01

    Cochlear implants must be inserted carefully to avoid damaging the delicate anatomical structures of the inner ear. This has motivated several approaches to improve the safety and efficacy of electrode array insertion by automating the process with specialized robotic or manual insertion tools. When such tools are used, they must be positioned at the entry point to the cochlea and aligned with the desired entry vector. This paper presents an image guidance system capable of accurately positioning a cochlear implant insertion tool. An optical tracking system localizes the insertion tool in physical space while a graphical user interface incorporates this with patient- specific anatomical data to provide error information to the surgeon in real-time. Guided by this interface, novice users successfully aligned the tool with an mean accuracy of 0.31 mm.

  14. Successful Rehabilitation of Partial Edentulous Maxilla and Mandible with New Type of Implants: Molecular Precision Implants

    Directory of Open Access Journals (Sweden)

    Matteo Danza

    2014-01-01

    Full Text Available The extraction of teeth results in rapid bone resorption both vertically and horizontally in the first month. The loss of alveolar ridge reduces the chance of implant rehabilitation. Atraumatic extraction, implant placement in extraction socket, and an immediate prosthesis have been proposed as alternative therapies to maintain the volume and contours tissue and reduce time and cost of treatment. The immediate load of implants is a universally practiced procedure; nevertheless a successful procedure requires expertise in both the clinical and the reconstructive stages using a solid implant system. Excellent primary stability and high bone-implant contact are only minimal requirements for any type of implant procedure. In this paper we present a case report using a new type of implants. The new type of implants, due to its sophisticated control system of production, provides to the implantologist a safe and reliable implant, with a macromorphology designed to ensure a close contact with the surrounding bone.

  15. In-vitro characterization of a cochlear implant system for recording of evoked compound action potentials

    Science.gov (United States)

    2012-01-01

    Background Modern cochlear implants have integrated recording systems for measuring electrically evoked compound action potentials of the auditory nerve. The characterization of such recording systems is important for establishing a reliable basis for the interpretation of signals acquired in vivo. In this study we investigated the characteristics of the recording system integrated into the MED-EL PULSARCI100 cochlear implant, especially its linearity and resolution, in order to develop a mathematical model describing the recording system. Methods In-vitro setup: The cochlear implant, including all attached electrodes, was fixed in a tank of physiologic saline solution. Sinusoidal signals of the same frequency but with different amplitudes were delivered via a signal generator for measuring and recording on a single electrode. Computer simulations: A basic mathematical model including the main elements of the recording system, i.e. amplification and digitalization stage, was developed. For this, digital output for sinusoidal input signals of different amplitudes were calculated using in-vitro recordings as reference. Results Using an averaging of 100 measurements the recording system behaved linearly down to approximately -60 dB of the input signal range. Using the same method, a system resolution of 10 μV was determined for sinusoidal signals. The simulation results were in very good agreement with the results obtained from in-vitro experiments. Conclusions The recording system implemented in the MED-EL PULSARCI100 cochlear implant for measuring the evoked compound action potential of the auditory nerve operates reliably. The developed mathematical model provides a good approximation of the recording system. PMID:22531599

  16. An Implantable Cardiovascular Pressure Monitoring System with On-Chip Antenna and RF Energy Harvesting

    Directory of Open Access Journals (Sweden)

    Yu-Chun Liu

    2015-08-01

    Full Text Available An implantable wireless system with on-chip antenna for cardiovascular pressure monitor is studied. The implantable device is operated in a batteryless manner, powered by an external radio frequency (RF power source. The received RF power level can be sensed and wirelessly transmitted along with blood pressure signal for feedback control of the external RF power. The integrated electronic system, consisting of a capacitance-to-voltage converter, an adaptive RF powering system, an RF transmitter and digital control circuitry, is simulated using a TSMC 0.18 μm CMOS technology. The implanted RF transmitter circuit is combined with a low power voltage-controlled oscillator resonating at 5.8 GHz and a power amplifier. For the design, the simulation model is setup using ADS and HFSS software. The dimension of the antenna is 1 × 0.6 × 4.8 mm3 with a 1 × 0.6 mm2 on-chip circuit which is small enough to place in human carotid artery.

  17. Influence of implant properties and local delivery systems on the outcome in operative fracture care.

    Science.gov (United States)

    Metsemakers, W-J; Moriarty, T F; Nijs, S; Pape, H C; Richards, R G

    2016-03-01

    Fracture fixation devices are implanted into a growing number of patients each year. This may be attributed to an increase in the popularity of operative fracture care and the development of ever more sophisticated implants, which may be used in even the most difficult clinical cases. Furthermore, as the general population ages, fragility fractures become more frequent. With the increase in number of surgical interventions, the absolute number of complications of these surgical treatments will inevitably rise. Implant-related infection and compromised fracture healing remain the most challenging and prevalent complications in operative fracture care. Any strategy that can help to reduce these complications will not only lead to a faster and more complete resumption of activities, but will also help to reduce the socio-economic impact. In this review we describe the influence of implant design and material choice on complication rates in trauma patients. Furthermore, we discuss the importance of local delivery systems, such as implant coatings and bone cement, and how these systems may have an impact on the prevalence, prevention and treatment outcome of these complications. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Three-dimensional accuracy of a digitally coded healing abutment implant impression system.

    Science.gov (United States)

    Ng, Simon D; Tan, Keson B; Teoh, K H; Cheng, Ansgar C; Nicholls, Jack I

    2014-01-01

    This study examined the three-dimensional (3D) accuracy of the Encode Impression System (EN) in transferring the locations of two implants from master models to test models and compared this to the direct impression (DI) technique. The effect of interimplant angulation on the 3D accuracy of both impression techniques was also evaluated. Seven sectional polymethyl methacrylate mandibular arch master models were fabricated with implants in the first premolar and first molar positions. The implants were placed parallel to each other or angulated mesiodistally or buccolingually with total divergent angles of 10, 20, or 30 degrees. Each master model was secured onto an aluminum block containing a gauge block, which defined the local coordinate references. Encode healing abutments were attached to the implants before impressions were made for the EN test models; pickup impression copings were attached for the DI test models. For the seven test groups of each impression technique, a total of 70 test models were fabricated (n = 5). The EN test models were sent to Biomet 3i for implant analog placement. The centroid of each implant or implant analog and the angular orientation of the long axis relative to the x- and y-axes were measured with a coordinate measuring machine. Statistical analyses were performed. Impression technique had a significant effect on y distortion, global linear distortion, and absolute xz and yz angular distortions. Interimplant angulation had significant effects on x and y distortions. However, neither impression technique nor interimplant angulation had a significant effect on z distortion. Distortions were observed with both impression techniques. However, the results suggest that EN was less accurate than DI.

  19. Systemic Assessment of Patients Undergoing Dental Implant ...

    African Journals Online (AJOL)

    These days, dental implants are becoming routinely used as a treatment option for rehabilitation of lost teeth. Conventionally, it is only after the completion of bone healing that the dental implants are loaded into the bone. Bone healing time is approximately 3 months and. 6 months for the mandible and maxilla, respectively.

  20. Influence of implant abutment material on the color of different ceramic crown systems.

    Science.gov (United States)

    Dede, Doğu Ömür; Armağanci, Arzu; Ceylan, Gözlem; Celik, Ersan; Cankaya, Soner; Yilmaz, Burak

    2016-11-01

    Ceramics are widely used for anterior restorations; however, clinical color reproduction still constitutes a challenge particularly when the ceramic crowns are used on titanium implant abutments. The purpose of this in vitro study was to investigate the effect of implant abutment material on the color of different ceramic material systems. Forty disks (11×1.5 mm, shade A2) were fabricated from medium-opacity (mo) and high-translucency (ht) lithium disilicate (IPS e.max) blocks, an aluminous ceramic (VITA In-Ceram Alumina), and a zirconia (Zirkonzahn) ceramic system. Disks were fabricated to represent 3 different implant abutments (zirconia, gold-palladium, and titanium) and dentin (composite resin, A2 shade) as background (11×2 mm). Disk-shaped composite resin specimens in A2 shade were fabricated to represent the cement layer. The color measurements of ceramic specimens were made on composite resin abutment materials using a spectrophotometer. CIELab color coordinates were recorded, and the color coordinates measured on composite resin background served as the control group. Color differences (ΔE 00 ) between the control and test groups were calculated. The data were analyzed with 2-way analysis of variance (ANOVA) and compared with the Tukey HSD test (α=.05). The ceramics system, abutment material, and their interaction were significant for ΔE 00 values (P2.25) were observed for lithium disilicate ceramics on titanium abutments (2.46-2.50). The ΔE 00 values of lithium disilicate ceramics for gold-palladium and titanium abutments were significantly higher than for other groups (P2.25) of an implant-supported lithium disilicate ceramic restoration may be clinically unacceptable if it is fabricated over a titanium abutment. Zirconia may be a more suitable abutment material for implant-supported ceramic restorations. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  1. Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes

    Science.gov (United States)

    Pena, A. E.; Kuntaegowdanahalli, S. S.; Abbas, J. J.; Patrick, J.; Horch, K. W.; Jung, R.

    2017-12-01

    Objective. A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm. Approach. Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity. Main results. Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10×  magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points. Significance. These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in

  2. Mechanical fatigue resistance of an implantable branched lead system for a distributed set of longitudinal intrafascicular electrodes.

    Science.gov (United States)

    Pena, A E; Kuntaegowdanahalli, S S; Abbas, J J; Patrick, J; Horch, K W; Jung, R

    2017-12-01

    A neural interface system has been developed that consists of an implantable stimulator/recorder can with a 15-electrode lead that trifurcates into three bundles of five individual wire longitudinal intrafascicular electrodes. This work evaluated the mechanical fatigue resistance of the branched lead and distributed electrode system under conditions designed to mimic anticipated strain profiles that would be observed after implantation in the human upper arm. Custom test setups and procedures were developed to apply linear or angular strain at four critical stress riser points on the lead and electrode system. Each test was performed to evaluate fatigue under a high repetition/low amplitude paradigm designed to test the effects of arm movement on the leads during activities such as walking, or under a low repetition/high amplitude paradigm designed to test the effects of more strenuous upper arm activities. The tests were performed on representative samples of the implantable lead system for human use. The specimens were fabricated using procedures equivalent to those that will be used during production of human-use implants. Electrical and visual inspections of all test specimens were performed before and after the testing procedures to assess lead integrity. Measurements obtained before and after applying repetitive strain indicated that all test specimens retained electrical continuity and that electrical impedance remained well below pre-specified thresholds for detection of breakage. Visual inspection under a microscope at 10×  magnification did not reveal any signs of damage to the wires or silicone sheathing at the stress riser points. These results demonstrate that the branched lead of this implantable neural interface system has sufficient mechanical fatigue resistance to withstand strain profiles anticipated when the system is implanted in an arm. The novel test setups and paradigms may be useful in testing other lead systems.

  3. Ion implantation

    International Nuclear Information System (INIS)

    Johnson, E.

    1986-01-01

    It is the purpose of the present paper to give a review of surface alloy processing by ion implantation. However, rather than covering this vast subject as a whole, the survey is confined to a presentation of the microstructures that can be found in metal surfaces after ion implantation. The presentation is limited to alloys processed by ion implantation proper, that is to processes in which the alloy compositions are altered significantly by direct injection of the implanted ions. The review is introduced by a presentation of the processes taking place during development of the fundamental event in ion implantation - the collision cascade, followed by a summary of the various microstructures which can be formed after ion implantation into metals. This is compared with the variability of microstructures that can be achieved by rapid solidification processing. The microstructures are subsequently discussed in the light of the processes which, as the implantations proceed, take place during and immediately after formation of the individual collision cascades. These collision cascades define the volumes inside which individual ions are slowed down in the implanted targets. They are not only centres for vigorous agitation but also the sources for formation of excess concentrations of point defects, which will influence development of particular microstructures. A final section presents a selection of specific structures which have been observed in different alloy systems. (orig./GSCH)

  4. Clinical and radiological results of patients treated with three treatment modalities for overdentures on implants of the ITI (R) Dental Implant System - A randomized controlled clinical trial

    NARCIS (Netherlands)

    Wismeijer, D; van Waas, MAJ; Mulder, J; Vermeeren, JIJF; Kalk, W

    In a randomized controlled clinical trial carried out at the Ignatius teaching hospital in Breda, The Netherlands, 110 edentulous patients with severe mandibular bone loss were treated with implants of the ITI(R) Dental Implant System using 3 different treatment strategies: a mandibular overdenture

  5. Cutaneous and systemic hypersensitivity reactions to metallic implants

    DEFF Research Database (Denmark)

    Basko-Plluska, Juliana L; Thyssen, Jacob P; Schalock, Peter C

    2011-01-01

    ) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions......Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous......, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure...

  6. Primary prevention of peri-implantitis: managing peri-implant mucositis.

    Science.gov (United States)

    Jepsen, Søren; Berglundh, Tord; Genco, Robert; Aass, Anne Merete; Demirel, Korkud; Derks, Jan; Figuero, Elena; Giovannoli, Jean Louis; Goldstein, Moshe; Lambert, France; Ortiz-Vigon, Alberto; Polyzois, Ioannis; Salvi, Giovanni E; Schwarz, Frank; Serino, Giovanni; Tomasi, Cristiano; Zitzmann, Nicola U

    2015-04-01

    comprising oral hygiene instructions and mechanical debridement revealed a reduction in clinical signs of inflammation; (vii) adjunctive measures (antiseptics, local and systemic antibiotics, air-abrasive devices) were not found to improve the efficacy of professionally administered plaque removal in reducing clinical signs of inflammation. Consensus was reached on recommendations for patients with dental implants and oral health care professionals with regard to the efficacy of measures to manage peri-implant mucositis. It was particularly emphasized that implant placement and prosthetic reconstructions need to allow proper personal cleaning, diagnosis by probing and professional plaque removal. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  7. Impact of implant design on primary stability of orthodontic mini-implants.

    Science.gov (United States)

    Wilmes, Benedict; Ottenstreuer, Stephanie; Su, Yu-Yu; Drescher, Dieter

    2008-01-01

    Skeletal anchorage with mini-implants has greatly broadened the treatment possibilities in orthodontics over the last few years. To reduce implant failure rates, it is advisable to obtain adequate primary stability. The aim of this study was to quantitatively analyze the impact of implant design and dimension on primary stability. Forty-two porcine iliac bone segments were prepared and embedded in resin. To evaluate the primary stability, we documented insertion torques of the following mini-implants: Aarhus Screw, AbsoAnchor, LOMAS, Micro-Anchorage-System, ORLUS and Spider Screw. In each bone, five Dual Top Screws were inserted for reference purposes to achieve comparability among the specimens. We observed wide variation in insertion torques and hence primary stability, depending on mini-implant design and dimension; the great impact that mini-implant diameter has on insertion torques was particularly conspicuous. Conical mini-implants achieved higher primary stabilities than cylindrical designs. The diameter and design of the mini-implant thread have a distinctive impact on primary stability. Depending on the region of insertion and local bone quality, the choice of the mini-implant design and size is crucial to establish sufficient primary stability.

  8. Precipitation processes in implanted materials

    International Nuclear Information System (INIS)

    Borders, J.A.

    1978-01-01

    Ion implantation is a nonequilibrium process. It is possible to implant materials with impurities to concentration levels which exceed the solid solubilities. The return of the system to thermodynamic equilibrium is often accomplished by precipitation of the implanted species or a compound involving atoms of both the host and the implanted species. This may involve long time scales when taking place at room temperature or it may take place during the implantation

  9. Zero-fluoroscopy permanent pacemaker implantation using Ensite NavX system: Clinical viability or fanciful technique?

    Science.gov (United States)

    Guo, Ping; Qiu, Jie; Wang, Yan; Chen, Guangzhi; Proietti, Riccardo; Fadhle, Al-Selmi; Zhao, Chunxia; Wen Wang, Dao

    2018-02-01

    Fluoroscopy is the imaging modality routinely used for cardiac device implantation and electrophysiological procedures. Due to the rising concern regarding the harmful effects of radiation exposure to both the patients and operation staffs, novel 3D mapping systems have been developed and implemented in electrophysiological procedure for the navigation of catheters inside the heart chambers. Their applicability in cardiac device implantation has been rarely reported. Our aim is to evaluate the feasibility and safety of permanent pacemaker implantation without fluoroscopy. From January 2012 to June 2016, six patients (50 ± 15 years, four of six were female, one of who was at the 25th week of gestation) who underwent permanent pacemaker implantation were included (zero-fluoroscopy group). Data from 20 consecutive cases of implantation performed under fluoroscopy guidance were chosen as a control group (fluoroscopy group). Total implantation procedure time for single-chamber pacemaker was 51.3 ± 13.1 minutes in the zero-fluoroscopy group and 42.6 ± 7.4 minutes in the fluoroscopy group (P  =  0.155). The implantation procedural time for a dual-chamber pacemaker was 88.3 ± 19.6 minutes and 67.3 ± 7.6 minutes in the zero-fluoroscopy and fluoroscopy groups (P  =  0.013), respectively. No complications were observed during the procedure and the follow-up in the two groups, and all pacemakers worked with satisfactory parameters. Ensite NavX system can be used as a reliable and safe zero-fluoroscopy approach for the implantation of single- or dual-chamber permanent pacemakers in specific patients, such as pregnant women or in extreme situations when the x-ray machine is not available. © 2017 The Authors. Pacing and Clinical Electrophysiology published by Wiley Periodicals, Inc.

  10. Long-term amnioinfusion through a subcutaneously implanted amniotic fluid replacement port system for treatment of PPROM in humans.

    Science.gov (United States)

    Tchirikov, Michael; Steetskamp, Joscha; Hohmann, Manfred; Koelbl, Heinz

    2010-09-01

    To introduce a novel method for the treatment of PPROM (preterm premature rupture of membranes) using continuous amnioinfusion via a subcutaneously implanted port system. After development and testing since 2001 in a fetal sheep model, the port system has been successfully implanted in two humans with PPROM. In the first case, the subcutaneous port system was implanted during the 23rd week of gestation in a 39-year-old 5th-gravida with PPROM since the 18th week of gestation; in the second case, the port system was implanted during the 24th week of gestation in a 27-year-old 3rd gravida with PPROM since the 21st week of gestation. After port implantation, 100ml/h saline solution was infused intermittently into the amniotic cavity. The whole course of treatment was supported by tocolysis. In the cases presented, gestation was terminated by cesarean section, in one case in the 29th week of gestation, and in the other case in the 30th week. The newborns showed no signs of lung hypoplasia and were successfully extubated on the 1st or 2nd day after delivery. Six months later the children did not exhibit any deviation from the normal development. Long-term amnioinfusion via a subcutaneously implanted port system could be used in humans with PPROM for prolongation of pregnancy and to avoid lung hypoplasia. Prospective randomized studies are ongoing. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Finite Element Analysis of Stress Distribution in Three Commonly Used Implant Systems in D2 and D4 Bone Densities

    Directory of Open Access Journals (Sweden)

    C Radha

    2016-01-01

    Materials and Methods : Pro-engineer 3-0 software was used to create the geometric models of the three implant systems (Nobel biocare, Biohorizon, Adin and two bone densities D2 and D4. Six 3D models were created to simulate each one of the three implant systems supporting a metal ceramic crown placed in two different densities of bone D2 and D4. The Poisson′s ratio(΅ and Youngs modulus(E of elasticity were assigned to different materials used for the models. Vertical and oblique loads of 450N each were applied on all six models. Von Mises stress analysis was done with ANSYS software. Results : Von Mises stresses were more within D4 type bone than D2 type, for all the three systems of implants and less stresses were seen in Biohorizon implant followed by Nobel Biocare and Adin implant particularly in D4 bone. Conclusion: The study concluded that the selection of a particular implant system should be based on the scientific research rather than on popularity.

  12. Load-Bearing Capacity and Retention of Newly Developed Micro-Locking Implant Prosthetic System: An In Vitro Pilot Study

    Directory of Open Access Journals (Sweden)

    Jae-Won Choi

    2018-04-01

    Full Text Available The aim of this study was to introduce the newly developed micro-locking implant prosthetic system and to evaluate the resulting its characteristics. To evaluate load-bearing capacity, 25 implants were divided into five groups: external-hexagon connection (EH, internal-octagon connection (IO, internal-hexagon connection (IH, one-body implant (OB, micro-locking implant system (ML. The maximum compressive load was measured using a universal testing machine (UTM according to the ISO 14801. Retention was evaluated in two experiments: (1 a tensile test of the structure modifications of the components (attachment and implant and (2 a tensile test after cyclic loading (total 5,000,000 cycles, 100 N, 2 Hz. The load-bearing capacity of the ML group was not significantly different from the other groups (p > 0.05. The number of balls in the attachment and the presence of a hexagonal receptacle did not show a significant correlation with retention (p > 0.05, but the shape of the retentive groove in the implant post had a statistically significant effect on retention (p < 0.05. On the other hand, the retention loss was observed during the initial 1,000,000 cycles, but an overall constant retention was maintained afterward. Various preclinical studies on this novel micro-locking implant prosthetic system should continue so that it can be applied in clinical practice.

  13. The implantation of a grid-connected PV system at CEPEL

    Energy Technology Data Exchange (ETDEWEB)

    Galdino, Marco Antonio, E-mail: marcoag@cepel.br

    2003-07-01

    This technical report presents the experience undertaken by CEPEL for implantation of a grid connected PV system at its headquarters, located in Rio de Janeiro, RJ, Brazil. This technology, although considered far from Brazilian reach, is expected to grow significantly in the near future. The paper describes briefly several aspects concerning the PV system and the DAS (data acquisition system) implemented in order to allow the continuous evaluation of its performance and operational conditions. The system was installed in December, 2002, and the data are still preliminary. (author)

  14. An Isolated Medial Patellofemoral Ligament Reconstruction with Patellar Tendon Autograft

    Directory of Open Access Journals (Sweden)

    Dariusz Witoński

    2013-01-01

    Full Text Available The aim of the study was to evaluate the results of the medial patellofemoral ligament reconstruction with a medial strip of patellar tendon autograft after a minimum 2-year followup. Ten patients (10 knees were operated on by one surgeon, according to the modified technique, described by Camanho, without any bone plug at free graft end. The mean age of the patients was 27.2 years (ranging from 18 to 42 years. The mean follow-up period was 3 years and 7 months. All patients were reviewed prospectively. At the last follow-up visit, all the patients demonstrated a significant improvement in terms of patellofemoral joint stability, all aspects of the KOOS questionnaire, and Kujala et al.’s score (59.7 points preoperatively and 84.4 points at the last followup. No patient revealed recurrent dislocation. The SF-36 score revealed a significant improvement in bodily pain, general health, physical role functioning, social role functioning, and physical functioning domains. The described MPFL reconstruction with the use of the medial 1/3rd of patella tendon is an effective procedure that gives satisfactorily patellofemoral joint functions, improves the quality of life, and provides much pain relief. It is relatively simple, surgically not extensive, and economically cost-effective procedure.

  15. From Fertilisation to Implantation in Mammalian Pregnancy—Modulation of Early Human Reproduction by the Endocannabinoid System

    Directory of Open Access Journals (Sweden)

    Justin C. Konje

    2010-09-01

    Full Text Available There is an increasing recognition that the endocannabinoid system is the crucial cytokine-hormone system regulating early human pregnancy. The synchronous development of the fertilized embryo and the endometrium to ensure timely implantation has been shown to be one of the pivotal steps to successful implantation. This development is thought to be regulated by a finely balanced relationship between various components of the endocannabinoid system in the endometrium, the embryo and the Fallopian tube. In addition, this system has also been shown to be involved in the regulation of the development and maturation of the gametes prior to fertilization. In this review, we will examine the evidence from animal and human studies to support the role of the endocannabinoid system in gametogenesis, fertilization, implantation, early pregnancy maintenance, and in immunomodulation of pregnancy. We will discuss the role of the cannabinoid receptors and the enzymes involved in the synthesis and degradation of the key endocannabinoid ligands (e.g., anandamide and 2-arachinoylglycerol in early reproduction.

  16. Intraoperative Cochlear Implant Device Testing Utilizing an Automated Remote System: A Prospective Pilot Study.

    Science.gov (United States)

    Lohmann, Amanda R; Carlson, Matthew L; Sladen, Douglas P

    2018-03-01

    Intraoperative cochlear implant device testing provides valuable information regarding device integrity, electrode position, and may assist with determining initial stimulation settings. Manual intraoperative device testing during cochlear implantation requires the time and expertise of a trained audiologist. The purpose of the current study is to investigate the feasibility of using automated remote intraoperative cochlear implant reverse telemetry testing as an alternative to standard testing. Prospective pilot study evaluating intraoperative remote automated impedance and Automatic Neural Response Telemetry (AutoNRT) testing in 34 consecutive cochlear implant surgeries using the Intraoperative Remote Assistant (Cochlear Nucleus CR120). In all cases, remote intraoperative device testing was performed by trained operating room staff. A comparison was made to the "gold standard" of manual testing by an experienced cochlear implant audiologist. Electrode position and absence of tip fold-over was confirmed using plain film x-ray. Automated remote reverse telemetry testing was successfully completed in all patients. Intraoperative x-ray demonstrated normal electrode position without tip fold-over. Average impedance values were significantly higher using standard testing versus CR120 remote testing (standard mean 10.7 kΩ, SD 1.2 vs. CR120 mean 7.5 kΩ, SD 0.7, p automated testing with regard to the presence of open or short circuits along the array. There were, however, two cases in which standard testing identified an open circuit, when CR120 testing showed the circuit to be closed. Neural responses were successfully obtained in all patients using both systems. There was no difference in basal electrode responses (standard mean 195.0 μV, SD 14.10 vs. CR120 194.5 μV, SD 14.23; p = 0.7814); however, more favorable (lower μV amplitude) results were obtained with the remote automated system in the apical 10 electrodes (standard 185.4 μV, SD 11.69 vs. CR

  17. Periodontal ligament formation around different types of dental titanium implants. I. The self-tapping screw type implant system

    DEFF Research Database (Denmark)

    Warrer, K; Karring, T; Gotfredsen, K

    1993-01-01

    The aim of this study was to determine if a periodontal ligament can form around self-tapping, screw type titanium dental implants. Implants were inserted in contact with the periodontal ligament of root tips retained in the mandibular jaws of 7 monkeys. In each side of the mandible, 1 premolar......, a periodontal ligament can form on self-tapping, screw type titanium dental implants in areas where a void is present between the surrounding bone and the implant at the time of insertion....... and 2 molars were removed in such a manner that in approximately half the cases, the root tips were retained. Following healing, the experimental areas were examined on radiographs, and sites were selected for the insertion of the implants, so that every second implant would have a close contact...

  18. Fate of bulk auto grafts in uncemented total hip arthroplasty: Evaluation by bone scintigraphy

    International Nuclear Information System (INIS)

    Simsek, A.; Cila, E.; Sener, E.; Senkoylu, A.; Sipahioglu, S.; Atasever, T.; Akdemir, Ozgur

    2006-01-01

    Objective was to review short term results of uncemented cup implantation and the fate of bulk femoral head autografts in patients with acetabular bone deficiency due to dysplasia of the hip. We used bone scintigraphy to assess the viability of the grafts. We treated 19 hip joints of 17 patients with osteoarthritis due to developmental dysplasia of the hip with uncemented total hip arthroplasty between 1997-2003 in the Department of Orthopedics and Traumatology, Gazi University, Ankara, Turkey. The average age was 49.1 (31-72 years), and the average follow up period was 36 months. We used femoral head autografts to reconstruct superolateral segmental deficiencies of the acetabuli. We evaluated the patients clinically and radiologically to assess acetabular loosening, and we used three-phase bone scintigraphy to evaluate the viability of the autograft.There was no acetabular component revision throughout the follow up period. There was no radiological evidence of graft resorption or graft displacement in any of the patients. In bone scintigraphy, we observed hyperemia in the blood pool phase, and the osteoblastic activity of the bone graft was at the level of the neighboring iliac bone. The application of a non-cemented acetabular component with femoral autograft in superolateral acetabulum deficiency increases the stability of the implant and increases the bone stock. It is not easy to evaluate the viability of the graft by the use of radiological methods. Bone scintigraphy gives sufficient information about the viability of the graft as a non-invasive method. (author)

  19. An image-guided planning system for endosseous oral implants.

    Science.gov (United States)

    Verstreken, K; Van Cleynenbreugel, J; Martens, K; Marchal, G; van Steenberghe, D; Suetens, P

    1998-10-01

    A preoperative planning system for oral implant surgery was developed which takes as input computed tomographies (CT's) of the jaws. Two-dimensional (2-D) reslices of these axial CT slices orthogonal to a curve following the jaw arch are computed and shown together with three-dimensional (3-D) surface rendered models of the bone and computer-aided design (CAD)-like implant models. A technique is developed for scanning and visualizing an eventual existing removable prosthesis together with the bone structures. Evaluation of the planning done with the system shows a difference between 2-D and 3-D planning methods. Validation studies measure the benefits of the 3-D approach by comparing plans made in 2-D mode only with those further adjusted using the full 3-D visualization capabilities of the system. The benefits of a 3-D approach are then evident where a prosthesis is involved in the planning. For the majority of the patients, clinically important adjustments and optimizations to the 2-D plans are made once the 3-D visualization is enabled, effectively resulting in a better plan. The alterations are related to bone quality and quantity (p biomechanics (p < 0.005), and esthetics (p < 0.005), and are so obvious that the 3-D plan stands out clearly (p < 0.005). The improvements often avoid complications such as mandibular nerve damage, sinus perforations, fenestrations, or dehiscences.

  20. Implant experience with an implantable hemodynamic monitor for the management of symptomatic heart failure.

    Science.gov (United States)

    Steinhaus, David; Reynolds, Dwight W; Gadler, Fredrik; Kay, G Neal; Hess, Mike F; Bennett, Tom

    2005-08-01

    Management of congestive heart failure is a serious public health problem. The use of implantable hemodynamic monitors (IHMs) may assist in this management by providing continuous ambulatory filling pressure status for optimal volume management. The Chronicle system includes an implanted monitor, a pressure sensor lead with passive fixation, an external pressure reference (EPR), and data retrieval and viewing components. The tip of the lead is placed near the right ventricular outflow tract to minimize risk of sensor tissue encapsulation. Implant technique and lead placement is similar to that of a permanent pacemaker. After the system had been successfully implanted in 148 patients, the type and frequency of implant-related adverse events were similar to a single-chamber pacemaker implant. R-wave amplitude was 15.2 +/- 6.7 mV and the pressure waveform signal was acceptable in all but two patients in whom presence of artifacts required lead repositioning. Implant procedure time was not influenced by experience, remaining constant throughout the study. Based on this evaluation, permanent placement of an IHM in symptomatic heart failure patients is technically feasible. Further investigation is warranted to evaluate the use of the continuous hemodynamic data in management of heart failure patients.

  1. A low power flash-FPGA based brain implant micro-system of PID control.

    Science.gov (United States)

    Lijuan Xia; Fattah, Nabeel; Soltan, Ahmed; Jackson, Andrew; Chester, Graeme; Degenaar, Patrick

    2017-07-01

    In this paper, we demonstrate that a low power flash FPGA based micro-system can provide a low power programmable interface for closed-loop brain implant inter- faces. The proposed micro-system receives recording local field potential (LFP) signals from an implanted probe, performs closed-loop control using a first order control system, then converts the signal into an optogenetic control stimulus pattern. Stimulus can be implemented through optoelectronic probes. The long term target is for both fundamental neuroscience applications and for clinical use in treating epilepsy. Utilizing our device, closed-loop processing consumes only 14nJ of power per PID cycle compared to 1.52μJ per cycle for a micro-controller implementation. Compared to an application specific digital integrated circuit, flash FPGA's are inherently programmable.

  2. Polymer-based wireless implantable sensor and platform for systems biology study

    Science.gov (United States)

    Xue, Ning

    Wireless implantable MEMS (microelectromechanical systems) devices have been developed over the past decade based on the combination of bio-MEMS and Radio frequency (RF) MEMS technology. These devices require the components of wireless telemetric antenna and the corresponding circuit. In the meanwhile, biocompatible material needs to be involved in the devices design. To supply maximum power upon the implantable device at given power supply from the external coil circuit, this dissertation theoretically analyzed the mutual inductance under the positions of variety of vertical distances, lateral displacements and angular misalignments between two coils in certain surgical coils misalignment situations. A planar spiral coil has been developed as the receiver coil of the coupling system. To get maximum induced voltage over the receiver circuit, different geometries of the power coil, system operation frequencies were investigated. An intraocular pressure (IOP) sensor has been developed consisting of only biocompatible matierials-SU-8 and gold. Its size is sufficiently small to be implanted in the eye. The measurement results showed that it has relatively linear pressure response, high resolution and relatively long working stability in saline environment. Finally, a simple and low cost micro-wells bio-chip has been developed with sole polydimethylsiloxane (PDMS) to be used for single cell or small group cells isolation. By performing atomic force microscopy (AFM), contact angle and x-ray photoelectron spectroscopy (XPS) measurements on the PDMS surfaces under various surface treatment conditions, the physical and chemical surface natures were thoroughly analyzed as the basis of study of cells attachment and isolation to the surfaces.

  3. Osseointegration of zirconia implants: an SEM observation of the bone-implant interface.

    Science.gov (United States)

    Depprich, Rita; Zipprich, Holger; Ommerborn, Michelle; Mahn, Eduardo; Lammers, Lydia; Handschel, Jörg; Naujoks, Christian; Wiesmann, Hans-Peter; Kübler, Norbert R; Meyer, Ulrich

    2008-11-06

    The successful use of zirconia ceramics in orthopedic surgery led to a demand for dental zirconium-based implant systems. Because of its excellent biomechanical characteristics, biocompatibility, and bright tooth-like color, zirconia (zirconium dioxide, ZrO2) has the potential to become a substitute for titanium as dental implant material. The present study aimed at investigating the osseointegration of zirconia implants with modified ablative surface at an ultrastructural level. A total of 24 zirconia implants with modified ablative surfaces and 24 titanium implants all of similar shape and surface structure were inserted into the tibia of 12 Göttinger minipigs. Block biopsies were harvested 1 week, 4 weeks or 12 weeks (four animals each) after surgery. Scanning electron microscopy (SEM) analysis was performed at the bone implant interface. Remarkable bone attachment was already seen after 1 week which increased further to intimate bone contact after 4 weeks, observed on both zirconia and titanium implant surfaces. After 12 weeks, osseointegration without interposition of an interfacial layer was detected. At the ultrastructural level, there was no obvious difference between the osseointegration of zirconia implants with modified ablative surfaces and titanium implants with a similar surface topography. The results of this study indicate similar osseointegration of zirconia and titanium implants at the ultrastructural level.

  4. Comparison between lamellar keratoplasties produced by conjunctival pedicle and free corneal autografts. Experimental study in the dog (Canis familiaris - LINNAEUS, 1758

    Directory of Open Access Journals (Sweden)

    José Luiz Laus

    1996-03-01

    Full Text Available A comparative study of conjunctival pedicle and corneal autografts, for experimental healing of superficial keratectomies in dogs (Canis familiaris was performed. It was carried out by using 24 animals, and the technical procedures were analysed according to clinical, histologic and scanning electron microscopy parameters, in early and late postoperative periods. The obtained results are believed to represent feasible methods of proteresis, applied to the healing ophthalmic surgery. There were few, irrelevant differences between the two tested techniques.

  5. Effect of autoclave devitalization on autograft incorporation and bone morphogenetic protein of tibia in Sprague-Dawley rats

    Directory of Open Access Journals (Sweden)

    Anak A.G.Y. Asmara

    2014-06-01

    Full Text Available Background: Heating process with autoclave is one of limb salvage modalities that are widely used. but the results are not satisfying, due to mechanical bone fragility. However, considering this treatment modality is widely accepted in terms of financial, religion and sociocultural aspects, we conducted a on study rats treated with resection and reconstruction with autoclave heating method to assess bone healing by sequential radiology, histopathologic osteoblasts count, and bone morphogenetic protein (BMP.Methods: Thirty six Sprague-Dawley rats were divided into two groups with one group being the autoclave group and others served as control group. In both groups, the tibial diaphysis was extracted en bloc for 7 mm. All groups were kept for 8 weeks and treated under the same condition except the autoclave group, where the extracted bones were put into autoclave at 134°C for 15 minutes and refixed again with k-wire. We performed radiological examination at 5th and 8th week using Lane and Sandhu radiological score. After extraction, the tibial bones were inspected for histological pattern using Salked modified score, osteoblast quantity counting and BMP-2 values.Results: There were statistically significant diffences between control and autoclave group on radiological score at 5th (5.12 ± 1.6 g vs 3.21 ± 2.42, p = 0.023 and 8th week (6.06 ± 1.71 vs 4.29 ± 2.53, p = 0.040, histological score between groups (6.06 ± 1.14 vs 4.14 ± 1.99, p = 0.005, osteoblast count (p < 0.001, and BMP-2 expression,  respectively.Conclusion: Autoclave recycling autograft lowered the speed of graft incorporation and BMP-2 expression. Therefore, autoclave recycling autograft as a method of limb salvage surgery must be reevaluated and not considered to be applied for treatment in bone malignancy.  

  6. Intramedullary screw fixation with bone autografting to treat proximal fifth metatarsal metaphyseal-diaphyseal fracture in athletes: a case series

    Directory of Open Access Journals (Sweden)

    Tsukada Sachiyuki

    2012-07-01

    Full Text Available Abstract Background Delayed unions or refractures are not rare following surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fractures. Intramedullary screw fixation with bone autografting has the potential to resolve the issue. The purpose of this study was to evaluate the result of the procedure. Methods The authors retrospectively reviewed 15 athletes who underwent surgical treatment for proximal fifth metatarsal metaphyseal-diaphyseal fracture. Surgery involved intramedullary cannulated cancellous screw fixation after curettage of the fracture site, followed by bone autografting. Postoperatively, patients remain non weight-bearing in a splint or cast for two weeks and without immobilization for an additional two weeks. Full weight-bearing was allowed six weeks postoperatively. Running was permitted after radiographic bone union, and return-to-play was approved after gradually increasing the intensity. Results All patients returned to their previous level of athletic competition. Mean times to bone union, initiation of running, and return-to-play were 8.4, 8.8, and 12.1 weeks, respectively. Although no delayed unions or refractures was observed, distal diaphyseal stress fractures at the distal tip of the screw occurred in two patients and a thermal necrosis of skin occurred in one patient. Conclusions There were no delayed unions or refractures among patients after carrying out a procedure in which bone grafts were routinely performed, combined with adequate periods of immobilization and non weight-bearing. These findings suggest that this procedure may be useful option for athletes to assuring return to competition level.

  7. Spiral-Shaped Piezoelectric MEMS Cantilever Array for Fully Implantable Hearing Systems

    Directory of Open Access Journals (Sweden)

    Péter Udvardi

    2017-10-01

    Full Text Available Fully implantable, self-powered hearing aids with no external unit could significantly increase the life quality of patients suffering severe hearing loss. This highly demanding concept, however, requires a strongly miniaturized device which is fully implantable in the middle/inner ear and includes the following components: frequency selective microphone or accelerometer, energy harvesting device, speech processor, and cochlear multielectrode. Here we demonstrate a low volume, piezoelectric micro-electromechanical system (MEMS cantilever array which is sensitive, even in the lower part of the voice frequency range (300–700 Hz. The test array consisting of 16 cantilevers has been fabricated by standard bulk micromachining using a Si-on-Insulator (SOI wafer and aluminum nitride (AlN as a complementary metal-oxide-semiconductor (CMOS and biocompatible piezoelectric material. The low frequency and low device footprint are ensured by Archimedean spiral geometry and Si seismic mass. Experimentally detected resonance frequencies were validated by an analytical model. The generated open circuit voltage (3–10 mV is sufficient for the direct analog conversion of the signals for cochlear multielectrode implants.

  8. An Unusual Bone Loss Around Implants

    Directory of Open Access Journals (Sweden)

    Amirreza Rokn

    2013-01-01

    Full Text Available AbstractPre-implant disease is an inflammatory process, which can affect the surrounding tissues of a functional Osseointegrated implant that is usually as a result of a disequilibrium between the micro-flora and the body defense system.This case reports a 57 years old male with unusual bone loss around dental implants.This was an unusual case of peri-implantitis which occurred only in the implants on one side of the mouth although they all were unloaded implants.

  9. rhBMP-2 (ACS and CRM formulations) overcomes pseudarthrosis in a New Zealand white rabbit posterolateral fusion model.

    Science.gov (United States)

    Lawrence, James P; Waked, Walid; Gillon, Thomas J; White, Andrew P; Spock, Christopher R; Biswas, Debdut; Rosenberger, Patricia; Troiano, Nancy; Albert, Todd J; Grauer, Jonathan N

    2007-05-15

    The study design consisted of a New Zealand white rabbit model of pseudarthrosis repair. Study groups consisting of no graft, autograft, or recombinant human bone morphogenetic protein-2 (rhBMP-2) with absorbable collagen sponge (ACS) or compression resistant matrix (CRM) were evaluated. To evaluate the relative efficacy of bone graft materials (autograft, ACS, and CRM). rhBMP-2 has been shown to have a 100% fusion rate in a primary rabbit fusion model, even in the presence of nicotine, which is known to inhibit fusion. Seventy-two New Zealand white rabbits underwent posterolateral lumbar fusion with iliac crest autograft. To establish pseudarthroses, nicotine was administered to all animals. At 5 weeks, the spines were explored and all pseudarthroses were redecorticated and implanted with no graft, autograft, rhBMP-2/ACS, or rhBMP-2/CRM. At 10 weeks, fusions were assessed by manual palpation and histology. Eight rabbits (11%) were lost to complications. At 5 weeks, 66 (97%) had pseudarthroses. At 10 weeks, attempted pseudarthrosis repairs were fused in 1 of 16 of no graft rabbits (6%), 5 of 17 autograft rabbits (29%), and 31 of 31 rhBMP-2 rabbits (with ACS or CRM) (100%). Histologic analysis demonstrated more mature bone formation in the rhBMP-2 groups. The 2 rhBMP-2 formulations led to significantly higher fusion rates and histologic bone formation than no graft and autograft controls in this pseudarthrosis repair model.

  10. DRUGAS: implantable telemetric system for measuring the portal venous pressure: assembly aspects

    Directory of Open Access Journals (Sweden)

    Fischer Roland

    2017-09-01

    Full Text Available Developing an implantable, telemetric pressure measuring system for venous applications makes a high degree of miniaturization necessary. Thus the influence on the measurement environment is minimized and the risk of thrombosis at small flow blood velocities is decreased. But these systems are limited in terms of accuracy and resolution. The asked system requirements could only be reached by optimising the assembly and encapsulation techniques. To achieve the high degree of miniaturization numerical simulations were performed on the shape and size of the implant and led to the development of a specific metal housing consisting of two main components. A small measuring chamber will be placed into the portal vein and is rigidly fixed to a flat circular part that contains the pressure sensor chip and a transponder board and will be located outside on top of the vein. The main focus of the assembly process was based on a stress-free design and mounting of the components.

  11. Effect of implant position, angulation, and attachment height on peri-implant bone stress associated with mandibular two-implant overdentures: a finite element analysis.

    Science.gov (United States)

    Hong, Hae Ryong; Pae, Ahran; Kim, Yooseok; Paek, Janghyun; Kim, Hyeong-Seob; Kwon, Kung-Rock

    2012-01-01

    The aim of this study was to analyze and compare the level and distribution of peri-implant bone stresses associated with mandibular two-implant overdentures with different implant positions. Mathematical models of mandibles and overdentures were designed using finite element analysis software. Two intraosseous implants and ball attachment systems were placed in the interforaminal region. The overdenture, which was supported by the two implants, was designed to withstand bilateral and unilateral vertical masticatory loads (total 100 N). In all, eight types of models, which differed according to assigned implant positions, height of attachments, and angulation, were tested: MI (model with implants positioned in the lateral incisor sites), MC (implants in canine sites), MP (implants in premolar sites), MI-Hi (greater height of attachments), MC-M (canine implants placed with mesial inclination), MC-D (canine implants placed with distal inclination), MC-B (canine implants placed with buccal inclination), and MC-L (canine implants placed with lingual inclination). Peri-implant bone stress levels associated with overdentures retained by lateral incisor implants resulted in the lowest stress levels and the highest efficiency in distributing peri-implant stress. MI-Hi showed increased stress levels and decreased efficiency in stress distribution. As the implants were inclined, stress levels increased and the efficiency of stress distribution decreased. Among the inclined models, MC-B showed the lowest stress level and best efficiency in stress distribution. The lowest stress and the best stability of implants in mandibular two-implant overdentures were obtained when implants were inserted in lateral incisor areas with shorter attachments and were placed parallel to the long axes of the teeth.

  12. Embedded System for Prosthetic Control Using Implanted Neuromuscular Interfaces Accessed Via an Osseointegrated Implant.

    Science.gov (United States)

    Mastinu, Enzo; Doguet, Pascal; Botquin, Yohan; Hakansson, Bo; Ortiz-Catalan, Max

    2017-08-01

    Despite the technological progress in robotics achieved in the last decades, prosthetic limbs still lack functionality, reliability, and comfort. Recently, an implanted neuromusculoskeletal interface built upon osseointegration was developed and tested in humans, namely the Osseointegrated Human-Machine Gateway. Here, we present an embedded system to exploit the advantages of this technology. Our artificial limb controller allows for bioelectric signals acquisition, processing, decoding of motor intent, prosthetic control, and sensory feedback. It includes a neurostimulator to provide direct neural feedback based on sensory information. The system was validated using real-time tasks characterization, power consumption evaluation, and myoelectric pattern recognition performance. Functionality was proven in a first pilot patient from whom results of daily usage were obtained. The system was designed to be reliably used in activities of daily living, as well as a research platform to monitor prosthesis usage and training, machine-learning-based control algorithms, and neural stimulation paradigms.

  13. [Fusion implants of carbon fiber reinforced plastic].

    Science.gov (United States)

    Früh, H J; Liebetrau, A; Bertagnoli, R

    2002-05-01

    Carbon fiber reinforced plastics (CFRP) are used in the medical field when high mechanical strength, innovative design, and radiolucency (see spinal fusion implants) are needed. During the manufacturing process of the material CFRP carbon fibers are embedded into a resin matrix. This resin material could be thermoset (e.g., epoxy resin EPN/DDS) or thermoplastic (e.g., PEAK). CFRP is biocompatible, radiolucent, and has higher mechanical capabilities compared to other implant materials. This publication demonstrates the manufacturing process of fusion implants made of a thermoset matrix system using a fiber winding process. The material has been used clinically since 1994 for fusion implants of the cervical and lumbar spine. The results of the fusion systems CORNERSTONE-SR C (cervical) and UNION (lumbar) showed no implant-related complications. New implant systems made of this CFRP material are under investigation and are presented.

  14. Implanting inequality: empirical evidence of social and ethical risks of implantable radio-frequency identification (RFID) devices.

    Science.gov (United States)

    Monahan, Torin; Fisher, Jill A

    2010-10-01

    The aim of this study was to assess empirically the social and ethical risks associated with implantable radio-frequency identification (RFID) devices. Qualitative research included observational studies in twenty-three U.S. hospitals that have implemented new patient identification systems and eighty semi-structured interviews about the social and ethical implications of new patient identification systems, including RFID implants. The study identified three primary social and ethical risks associated with RFID implants: (i) unfair prioritization of patients based on their participation in the system, (ii) diminished trust of patients by care providers, and (iii) endangerment of patients who misunderstand the capabilities of the systems. RFID implants may aggravate inequalities in access to care without any clear health benefits. This research underscores the importance of critically evaluating new healthcare technologies from the perspective of both normative ethics and empirical ethics.

  15. Complication incidence of two implant systems up to six years: a comparison between internal and external connection implants.

    Science.gov (United States)

    Chae, Sung-Wook; Kim, Young-Sung; Lee, Yong-Moo; Kim, Won-Kyung; Lee, Young-Kyoo; Kim, Su-Hwan

    2015-02-01

    This study was conducted to compare the cumulative survival rates (CSRs) and the incidence of postloading complications (PLCs) between a bone-level internal connection system (ICS-BL) and an external connection system (ECS). The medical records of patients treated with either a ICS-BL or ECS between 2007 and 2010 at Asan Medical Center were reviewed. PLCs were divided into two categories: biological and technical. Biological complications included >4 mm of probing pocket depth, thread exposure in radiographs, and soft tissue complications, whereas technical complications included chipping of the veneering material, fracture of the implant, fracture of the crown, loosening or fracture of the abutment or screw, loss of retention, and loss of access hole filling material. CSRs were determined by a life-table analysis and compared using the log-rank chi-square test. The incidence of PLC was compared with the Pearson chi-squared test. A total of 2,651 implants in 1,074 patients (1,167 ICS-BLs in 551 patients and 1,484 ECSs in 523 patients) were analyzed. The average observation periods were 3.4 years for the ICS-BLs and 3.1 years for the ECSs. The six-year CSR of all implants was 96.1% (94.9% for the ICS-BLs and 97.1% for the ECSs, P=0.619). Soft tissue complications were more frequent with the ECSs (P=0.005) and loosening or fracture of the abutment or screw occurred more frequently with the ICS-BLs (Plimitations of this study, the ICS-BL was more prone to technical complications while the ECS was more vulnerable to biological complications.

  16. A biomechanical testing system to determine micromotion between hip implant and femur accounting for deformation of the hip implant: Assessment of the influence of rigid body assumptions on micromotions measurements.

    Science.gov (United States)

    Leuridan, Steven; Goossens, Quentin; Roosen, Jorg; Pastrav, Leonard; Denis, Kathleen; Mulier, Michiel; Desmet, Wim; Vander Sloten, Jos

    2017-02-01

    Accurate pre-clinical evaluation of the initial stability of new cementless hip stems using in vitro micromotion measurements is an important step in the design process to assess the new stem's potential. Several measuring systems, linear variable displacement transducer-based and other, require assuming bone or implant to be rigid to obtain micromotion values or to calculate derived quantities such as relative implant tilting. An alternative linear variable displacement transducer-based measuring system not requiring a rigid body assumption was developed in this study. The system combined advantages of local unidirectional and frame-and-bracket micromotion measuring concepts. The influence and possible errors that would be made by adopting a rigid body assumption were quantified. Furthermore, as the system allowed emulating local unidirectional and frame-and-bracket systems, the influence of adopting rigid body assumptions were also analyzed for both concepts. Synthetic and embalmed bone models were tested in combination with primary and revision implants. Single-legged stance phase loading was applied to the implant - bone constructs. Adopting a rigid body assumption resulted in an overestimation of mediolateral micromotion of up to 49.7μm at more distal measuring locations. Maximal average relative rotational motion was overestimated by 0.12° around the anteroposterior axis. Frontal and sagittal tilting calculations based on a unidirectional measuring concept underestimated the true tilting by an order of magnitude. Non-rigid behavior is a factor that should not be dismissed in micromotion stability evaluations of primary and revision femoral implants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. Ion beam system for implanting industrial products of various shapes

    International Nuclear Information System (INIS)

    Denholm, A.S.; Wittkower, A.

    1985-01-01

    Implantation of metals and ceramics with ions of nitrogen and other species has improved surface properties such as friction, wear and corrosion in numerous industrial applications. Zymet has built a production machine to take advantage of this process which can implant a 2 x 10 17 ions/cm 2 dose of nitrogen ions into a 20 cm x 20 cm area in about 30 min using a 100 keV beam. Treatment is accomplished by mounting the product on a cooled, tiltable, turntable which rotates continuously, or is indexed in 15 0 steps to expose different surfaces in fixed position. Product cooling is accomplished by using a chilled eutectic metal to mount and grip the variously shaped objects. A high voltage supply capable of 10 mA at 100 kV is used, and the equipment is microcomputer controlled via serial light links. All important machine parameters are presented in sequenced displays on a CRT. Uniformity of treatment and accumulated dose are monitored by a Faraday cup system which provides the microprocessor with data for display of time to completion on the process screen. For routine implants the operator requires only two buttons; one for chamber vacuum control, and the other for process start and stop. (orig.)

  18. Implementation of wireless power transfer and communications for an implantable ocular drug delivery system.

    Science.gov (United States)

    Tang, T B; Smith, S; Flynn, B W; Stevenson, J T M; Gundlach, A M; Reekie, H M; Murray, A F; Renshaw, D; Dhillon, B; Ohtori, A; Inoue, Y; Terry, J G; Walton, A J

    2008-09-01

    A wireless power transfer and communication system based on near-field inductive coupling has been designed and implemented. The feasibility of using such a system to remotely control drug release from an implantable drug delivery system is addressed. The architecture of the wireless system is described and the signal attenuation over distance in both water and phosphate buffered saline is studied. Additionally, the health risk due to exposure to radio frequency (RF) radiation is examined using a biological model. The experimental results demonstrate that the system can trigger the release of drug within 5 s, and that such short exposure to RF radiation does not produce any significant (system could replace a chemical battery in an implantable system, eliminating the risks associated with battery failure and leakage and also allowing more compact designs for applications such as drug delivery.

  19. Location of unaccessible implant surface areas during debridement in simulated peri-implantitis therapy

    OpenAIRE

    Steiger-Ronay, Valerie; Merlini, Andrea; Wiedemeier, Daniel B.; Schmidlin, Patrick R.; Attin, Thomas; Sahrmann, Philipp

    2017-01-01

    Background An in vitro model for peri-implantitis treatment was used to identify areas that are clinically difficult to clean by analyzing the pattern of residual stain after debridement with commonly employed instruments. Methods Original data from two previous publications, which simulated surgical (SA) and non-surgical (NSA) implant debridement on two different implant systems respectively, were reanalyzed regarding the localization pattern of residual stains after instrumentation. Two bli...

  20. Electromagnetic Interference in Patients with Implanted Cardioverter-Defibrillators and Implantable Loop Recorders

    Directory of Open Access Journals (Sweden)

    Marcos de Sousa

    2002-07-01

    Full Text Available Modern life exposes us all to an ever-increasing number of potential sources of electromagnetic interference (EMI and patients with Implantable rhythm devices (IRD like pacemakers, implantable cardioverter defibrillators or implantable loop recorders often ask about the use of microwave ovens, walking through airport metal detectors and the use of cellular phones. Electromagnetic interference occurs when electromagnetic waves emitted by one device impede the normal function of another electronic device. The potential for interaction between implanted pacing systems and cardioverter-defibrillators (electromagnetic interference, EMI has been recognized for years.1,2,3,4. It has been shown that EMI can produce clinically significant effects on patients with implanted pacemakers and ICDs. For these reasons the following text discusses the influence of several EMI generating devices on IRD .

  1. Description of the condition of the implant-prosthesis system: a transverse study

    International Nuclear Information System (INIS)

    Salazar Salgado, Walter

    2008-01-01

    Current condition of the implant-prosthesis system of the patients attended in the Facultad de Odontologia de la Universidad de Costa Rica is described, in the included period from January 2001 to December 2006. Parameters of comparison will be established for future evaluations. An appointment was scheduled with each patient to review. A radiovisiograph was used for digital radiography with parallel technique and radiographic positioners, for anterior and posterior sector. In addition, a questionnaire was applied to all patients. The percentage of survival of the implants placed in the years 2001-2006, is 95.2 % and 92.4 % of the patients are satisfied with the aesthetic aspect of their restoration [es

  2. Accuracy of two digital implant impression systems based on confocal microscopy with variations in customized software and clinical parameters.

    Science.gov (United States)

    Giménez, Beatriz; Pradíes, Guillermo; Martínez-Rus, Francisco; Özcan, Mutlu

    2015-01-01

    To evaluate the accuracy of two digital impression systems based on the same technology but different postprocessing correction modes of customized software, with consideration of several clinical parameters. A maxillary master model with six implants located in the second molar, second premolar, and lateral incisor positions was fitted with six cylindrical scan bodies. Scan bodies were placed at different angulations or depths apical to the gingiva. Two experienced and two inexperienced operators performed scans with either 3D Progress (MHT) or ZFX Intrascan (Zimmer Dental). Five different distances between implants (scan bodies) were measured, yielding five data points per impression and 100 per impression system. Measurements made with a high-accuracy three-dimensional coordinate measuring machine (CMM) of the master model acted as the true values. The values obtained from the digital impressions were subtracted from the CMM values to identify the deviations. The differences between experienced and inexperienced operators and implant angulation and depth were compared statistically. Experience of the operator, implant angulation, and implant depth were not associated with significant differences in deviation from the true values with both 3D Progress and ZFX Intrascan. Accuracy in the first scanned quadrant was significantly better with 3D Progress, but ZFX Intrascan presented better accuracy in the full arch. Neither of the two systems tested would be suitable for digital impression of multiple-implant prostheses. Because of the errors, further development of both systems is required.

  3. Influence of Implant Positions and Occlusal Forces on Peri-Implant Bone Stress in Mandibular Two-Implant Overdentures: A 3-Dimensional Finite Element Analysis.

    Science.gov (United States)

    Alvarez-Arenal, Angel; Gonzalez-Gonzalez, Ignacio; deLlanos-Lanchares, Hector; Brizuela-Velasco, Aritza; Dds, Elena Martin-Fernandez; Ellacuria-Echebarria, Joseba

    2017-12-01

    The aim of this study was to evaluate and compare the bone stress around implants in mandibular 2-implant overdentures depending on the implant location and different loading conditions. Four 3-dimensional finite element models simulating a mandibular 2-implant overdenture and a Locator attachment system were designed. The implants were located at the lateral incisor, canine, second premolar, and crossed-implant levels. A 150 N unilateral and bilateral vertical load of different location was applied, as was 40 N when combined with midline load. Data for von Mises stress were produced numerically, color coded, and compared between the models for peri-implant bone and loading conditions. With unilateral loading, in all 4 models much higher peri-implant bone stress values were recorded on the load side compared with the no-load side, while with bilateral occlusal loading, the stress distribution was similar on both sides. In all models, the posterior unilateral load showed the highest stress, which decreased as the load was applied more mesially. In general, the best biomechanical environment in the peri-implant bone was found in the model with implants at premolar level. In the crossed-implant model, the load side greatly altered the biomechanical environment. Overall, the overdenture with implants at second premolar level should be the chosen design, regardless of where the load is applied. The occlusal loading application site influences the bone stress around the implant. Bilateral occlusal loading distributes the peri-implant bone stress symmetrically, while unilateral loading increases it greatly on the load side, no matter where the implants are located.

  4. A simple ion implantation system for solar cells

    International Nuclear Information System (INIS)

    Kenny, M.J.; Bird, J.R.; Broe, H.G.

    1982-11-01

    A project has been initiated to investigate simple but effective ion implantation and pulsed annealing techniques for the fabrication of high efficiency silicon solar cells. In particular, the method aims to eliminate the mass analyser and associated components from the implanter. A solid feed source is used in a clean ultra high vacuum environment to minimise impurities

  5. Localization and Tracking of Implantable Biomedical Sensors

    Directory of Open Access Journals (Sweden)

    Ilknur Umay

    2017-03-01

    Full Text Available Implantable sensor systems are effective tools for biomedical diagnosis, visualization and treatment of various health conditions, attracting the interest of researchers, as well as healthcare practitioners. These systems efficiently and conveniently provide essential data of the body part being diagnosed, such as gastrointestinal (temperature, pH, pressure parameter values, blood glucose and pressure levels and electrocardiogram data. Such data are first transmitted from the implantable sensor units to an external receiver node or network and then to a central monitoring and control (computer unit for analysis, diagnosis and/or treatment. Implantable sensor units are typically in the form of mobile microrobotic capsules or implanted stationary (body-fixed units. In particular, capsule-based systems have attracted significant research interest recently, with a variety of applications, including endoscopy, microsurgery, drug delivery and biopsy. In such implantable sensor systems, one of the most challenging problems is the accurate localization and tracking of the microrobotic sensor unit (e.g., robotic capsule inside the human body. This article presents a literature review of the existing localization and tracking techniques for robotic implantable sensor systems with their merits and limitations and possible solutions of the proposed localization methods. The article also provides a brief discussion on the connection and cooperation of such techniques with wearable biomedical sensor systems.

  6. Mandibular Reconstruction by Using a Liquid Nitrogen-Treated Autograft in a Dog with an Oral Tumor.

    Science.gov (United States)

    Okamura, Yasuhiko; Heishima, Kazuki; Motegi, Tomoki; Sasaki, Jun; Goryo, Masanobu; Nishida, Hideji; Tsuchiya, Hiroyuki; Katayama, Masaaki; Uzuka, Yuji

    A 10 yr old intact female German shepherd dog presented with a large peripheral odontogenic fibroma and malignant melanoma on her lower jaw. The tumor was resected with a unilateral subtotal rostral hemimandibulectomy. After the mandible was removed, it was devitalized intraoperatively by freezing it in liquid nitrogen. It was subsequently reimplanted. New bone tissue formed in the gap between the frozen bone and the host bone. The regenerated bone contained osteocytes, osteoblasts, and blood vessels. The cosmetic appearance of the dog was preserved. The dog had normal mastication. The malignant melanoma recurred rostral of the left canine tooth at 159 days after the reconstruction surgery. A subtotal hemimandibulectomy was consequently performed. This is the first reported case of mandibular reconstruction using a liquid nitrogen-treated autograft in a dog with oral tumors.

  7. A detection system for charged-particle decay studies with a continuous-implantation method

    Energy Technology Data Exchange (ETDEWEB)

    Sun, L.J. [China Institute of Atomic Energy, Beijing 102413 (China); Xu, X.X., E-mail: xuxinxing@ciae.ac.cn [China Institute of Atomic Energy, Beijing 102413 (China); Lin, C.J., E-mail: cjlin@ciae.ac.cn [China Institute of Atomic Energy, Beijing 102413 (China); Wang, J.S. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); Fang, D.Q. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, Z.H. [School of Physic and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Wang, Y.T. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Li, J. [School of Physic and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Yang, L.; Ma, N.R. [China Institute of Atomic Energy, Beijing 102413 (China); Wang, K. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Zang, H.L. [School of Physic and State Key Laboratory of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Wang, H.W.; Li, C.; Shi, C.Z.; Nie, M.W.; Li, X.F.; Li, H. [Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Shanghai 201800 (China); Ma, J.B.; Ma, P. [Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000 (China); and others

    2015-12-21

    A new detection system with high detection efficiency and low detection threshold has been developed for charged-particle decay studies, including β-delayed proton, α decay or direct proton emission from proton-rich nuclei. The performance was evaluated by using the β-delayed proton emitter {sup 24}Si produced by projectile fragmentation at the First Radioactive Ion Beam Line in Lanzhou. Under a continuous-beam mode, the isotopes of interest were implanted into two double-sided silicon strip detectors, where the subsequent decays were measured and correlated to the preceding implantations by using position and time information. The system allows us to measure protons with energies down to about 200 keV without obvious β background in the proton spectrum. Further application of the detection system can be extended to the measurements of β-delayed proton decay and the direct proton emission of more exotic proton-rich nuclei.

  8. FIRST USE OF STEREOLOGY TO QUANTIFY THE SURVIVAL OF FAT AUTOGRAFTS

    Directory of Open Access Journals (Sweden)

    Eduardo Serna Cuéllar

    2011-05-01

    Full Text Available It is not usual to perform quantitative analyses on surgical materials. Rather, they are evaluated clinically, through qualitative methods, and if quantitation is done, it is on a 2-dimensional basis. In this study, the long-term survival of fat autografts (FAG in 40 subjects with facial soft tissue defects is quantified. An adipose tissue preparation from the abdomen obtained through liposuction and centrifugation is injected subcutaneously. Approximately 14 months later, the treated area is biopsied. Extensive computer-based histological analyses were performed using the stereological method in order to directly obtain three parameters: volume fraction of adipocytes in the fat tissue (VV, density (number per volume of adipocytes in the fat tissue (NV, and the mean cell volume of adipocytes (VA in each tissue sample. A set of equations based on these three quantitative parameters is produced for evaluation of the volumetric survival fraction (VSF of FAG. The presented data evidenced a 66% survival fraction at the 14-month follow-up. In routine practice, it would be sufficient to perform this volumetric analysis on the injected and biopsied fat samples to know what fraction of the FAG has survived. This is an objective method for quantifying FAG survival and will allow a standardized comparison between different research series and authors.

  9. 21 CFR 880.6300 - Implantable radiofrequency transponder system for patient identification and health information.

    Science.gov (United States)

    2010-04-01

    ... patient identification and health information. 880.6300 Section 880.6300 Food and Drugs FOOD AND DRUG... radiofrequency transponder system for patient identification and health information. (a) Identification. An implantable radiofrequency transponder system for patient identification and health information is a device...

  10. A classification of growth friendly spine implants.

    Science.gov (United States)

    Skaggs, David L; Akbarnia, Behrooz A; Flynn, John M; Myung, Karen S; Sponseller, Paul D; Vitale, Michael G

    2014-01-01

    Various types of spinal implants have been used with the objective of minimizing spinal deformities while maximizing the spine and thoracic growth in a growing child with a spinal deformity. The aim of this study was to describe a classification system of growth friendly spinal implants to allow researchers and clinicians to have a common language and facilitate comparative studies. Growth friendly spinal implant systems fall into 3 categories based upon the forces of correction the implants exert on the spine, which are as follows: Distraction-based systems correct spinal deformities by mechanically applying a distractive force across a deformed segment with anchors at the top and bottom of the implants, which commonly attach to the spine, rib, and/or the pelvis. The present examples of distraction-based implants are spine-based or rib-based growing rods, vertical expandable titanium rib prosthesis, and remotely expandable devices. Compression-based systems correct spinal deformities with a compressive force applied to the convexity of the curve causing convex growth inhibition. This compressive force may be generated both mechanically at the time of implantation, as well as over time resulting from longitudinal growth of vertebral endplates hindered by the spinal implants. Examples of compression-based systems are vertebral staples and tethers. Guided growth systems correct spinal deformity by anchoring multiple vertebrae (usually including the apical vertebrae) to rods with mechanical forces including translation at the time of the initial implant. The majority of the anchors are not rigidly attached to the rods, thus permitting longitudinal growth over time as the anchors slide over the rods. Examples of guided growth systems include the Luque trolley and Shilla. Each system has its benefits and shortcomings. Knowledge of the fundamental principles upon which these systems are based may aid the clinician to choose an appropriate treatment for patients. Having a

  11. Augmentation Mammaplasty Using Implants: A Review

    Directory of Open Access Journals (Sweden)

    Susumu Takayanagi

    2012-09-01

    Full Text Available One of the techniques for augmentation mammaplasty is the procedure using implants. Eventhough this technique has been used for many years, there are still several controversial issuesto be discussed and overcome for patient safety. In this review article, capsular contracture,leak or rupture of the implants, possible systemic disease, relation with breast cancer, andrecent problems with Poly Implant Prothese implants are described and discussed.

  12. Indirect MR-arthrography in osteochondral autograft and crushed bone graft with a collagen membrane-Correlation with histology

    Energy Technology Data Exchange (ETDEWEB)

    Streitparth, F. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)], E-mail: florian.streitparth@charite.de; Schoettle, P.; Schell, H. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Lehmkuhl, L.; Madej, T.; Wieners, G. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Duda, G.N. [Center for Musculoskeletal Surgery, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany); Schroeder, R.J. [Klinik fuer Strahlenheilkunde, Charite, Campus Virchow-Klinikum, Humboldt-University, Berlin (Germany)

    2009-04-15

    Objective: To analyze the spectrum of findings in indirect MR-arthrography following osteochondral autograft transfer system (OATS) and crushed bone graft using a magnetic resonance imaging (MRI) scoring and grading system in relation to histology as the standard of reference. Materials and methods: Iatrogenic lesions were set at ovine condylar facets (n = 6/group), treated with OATS or crushed bone graft. 1.5 T MRI was performed 6 months after surgery using PD-weighted (w fat saturated (fs) fast spin echo (FSE), T1-w 2D, and 3D fs gradient echo (GE) sequences 30 min. after i.v. Gd-DTPA administration and passive joint exercise. The repair tissue was evaluated by two independent radiologists. The MR findings were compared to histology. Results: In all cases, MRI and histologic grading correlated well and showed significant superior repair in OATS at 6 months (p < 0.05), reproducing the original articular contour and a good subchondral restoration. FsT1-w3DGE proved most appropriate identifying characteristic post-operative findings: the OATS group demonstrated bone marrow edema at the donor site and the graft/host interface showed significant enhancement in indirect MR-arthrography, indicating fibrocartilage. After crushed bone graft, we found an irregular structure and significant contrast uptake, consistent with remnants of bone grafts surrounded by inflammatory tissue. Conclusion: Indirect MR-arthrography is an accurate, non-invasive monitoring tool following OATS and crushed bone graft as the MRI scoring and grading system allows a reliable evaluation of normal and pathological osteochondral repair with a high histologic correlation.

  13. Reliability of a semi-automated 3D-CT measuring method for tunnel diameters after anterior cruciate ligament reconstruction: A comparison between soft-tissue single-bundle allograft vs. autograft.

    Science.gov (United States)

    Robbrecht, Cedric; Claes, Steven; Cromheecke, Michiel; Mahieu, Peter; Kakavelakis, Kyriakos; Victor, Jan; Bellemans, Johan; Verdonk, Peter

    2014-10-01

    Post-operative widening of tibial and/or femoral bone tunnels is a common observation after ACL reconstruction, especially with soft-tissue grafts. There are no studies comparing tunnel widening in hamstring autografts versus tibialis anterior allografts. The goal of this study was to observe the difference in tunnel widening after the use of allograft vs. autograft for ACL reconstruction, by measuring it with a novel 3-D computed tomography based method. Thirty-five ACL-deficient subjects were included, underwent anatomic single-bundle ACL reconstruction and were evaluated at one year after surgery with the use of 3-D CT imaging. Three independent observers semi-automatically delineated femoral and tibial tunnel outlines, after which a best-fit cylinder was derived and the tunnel diameter was determined. Finally, intra- and inter-observer reliability of this novel measurement protocol was defined. In femoral tunnels, the intra-observer ICC was 0.973 (95% CI: 0.922-0.991) and the inter-observer ICC was 0.992 (95% CI: 0.982-0.996). In tibial tunnels, the intra-observer ICC was 0.955 (95% CI: 0.875-0.985). The combined inter-observer ICC was 0.970 (95% CI: 0.987-0.917). Tunnel widening was significantly higher in allografts compared to autografts, in the tibial tunnels (p=0.013) as well as in the femoral tunnels (p=0.007). To our knowledge, this novel, semi-automated 3D-computed tomography image processing method has shown to yield highly reproducible results for the measurement of bone tunnel diameter and area. This series showed a significantly higher amount of tunnel widening observed in the allograft group at one-year follow-up. Level II, Prospective comparative study. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Randomized study on the effect of single-implant versus two-implant retained overdentures on implant loss and muscle activity: a 12-month follow-up report.

    Science.gov (United States)

    Alqutaibi, A Y; Kaddah, A F; Farouk, M

    2017-06-01

    The objective was to evaluate and compare single- and two-implant retained overdentures for the rehabilitation of the edentulous mandible. Fifty-six edentulous subjects were eligible for inclusion. Using a random sampling system, a single implant or two implants were placed in the mandible. After 3 months, locator attachments were connected to the implants and the denture delivered with the retentive components incorporated in the denture base. Implant failure and muscle activity were evaluated at the 3-, 6-, and 12-month follow-up examinations. The study sample comprised 56 patients (32 male, 24 female), with a mean age of 58.2 years. A total of 84 implants were placed (28 in the single-implant group and 56 in the two-implant group). All patients completed the 12 months of follow-up. No significant differences were found between subjects in the two groups with respect to implant failure. With regard to improvements in muscle activity, the two-implant group showed statistically significant but perhaps not clinically important differences. Single-implant mandibular overdentures may be suggested as an alternative treatment modality for the rehabilitation of edentulous patients who cannot afford the cost of a two-implant overdenture. Copyright © 2017 International Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  15. Augmentation Mammaplasty Using Implants: A Review

    Directory of Open Access Journals (Sweden)

    Susumu Takayanagi

    2012-09-01

    Full Text Available One of the techniques for augmentation mammaplasty is the procedure using implants. Even though this technique has been used for many years, there are still several controversial issues to be discussed and overcome for patient safety. In this review article, capsular contracture, leak or rupture of the implants, possible systemic disease, relation with breast cancer, and recent problems with Poly Implant Prothese implants are described and discussed.

  16. Cutaneous and systemic hypersensitivity reactions to metallic implants.

    Science.gov (United States)

    Basko-Plluska, Juliana L; Thyssen, Jacob P; Schalock, Peter C

    2011-01-01

    Cutaneous reactions to metal implants, orthopedic or otherwise, are well documented in the literature. The first case of a dermatitis reaction over a stainless steel fracture plate was described in 1966. Most skin reactions are eczematous and allergic in nature, although urticarial, bullous, and vasculitic eruptions may occur. Also, more complex immune reactions may develop around the implants, resulting in pain, inflammation, and loosening. Nickel, cobalt, and chromium are the three most common metals that elicit both cutaneous and extracutaneous allergic reactions from chronic internal exposure. However, other metal ions as well as bone cement components can cause such hypersensitivity reactions. To complicate things, patients may also develop delayed-type hypersensitivity reactions to metals (ie, in-stent restenosis, prosthesis loosening, inflammation, pain, or allergic contact dermatitis) following the insertion of intravascular stents, dental implants, cardiac pacemakers, or implanted gynecologic devices. Despite repeated attempts by researchers and clinicians to further understand this difficult area of medicine, the association between metal sensitivity and cutaneous allergic reactions remains to be fully understood. This review provides an update of the current knowledge in this field and should be valuable to health care providers who manage patients with conditions related to this field.

  17. Immunological Response to Biodegradable Magnesium Implants

    Science.gov (United States)

    Pichler, Karin; Fischerauer, Stefan; Ferlic, Peter; Martinelli, Elisabeth; Brezinsek, Hans-Peter; Uggowitzer, Peter J.; Löffler, Jörg F.; Weinberg, Annelie-Martina

    2014-04-01

    The use of biodegradable magnesium implants in pediatric trauma surgery would render surgical interventions for implant removal after tissue healing unnecessary, thereby preventing stress to the children and reducing therapy costs. In this study, we report on the immunological response to biodegradable magnesium implants—as an important aspect in evaluating biocompatibility—tested in a growing rat model. The focus of this study was to investigate the response of the innate immune system to either fast or slow degrading magnesium pins, which were implanted into the femoral bones of 5-week-old rats. The main alloying element of the fast-degrading alloy (ZX50) was Zn, while it was Y in the slow-degrading implant (WZ21). Our results demonstrate that degrading magnesium implants beneficially influence the immune system, especially in the first postoperative weeks but also during tissue healing and early bone remodeling. However, rodents with WZ21 pins showed a slightly decreased phagocytic ability during bone remodeling when the degradation rate reached its maximum. This may be due to the high release rate of the rare earth-element yttrium, which is potentially toxic. From our results we conclude that magnesium implants have a beneficial effect on the innate immune system but that there are some concerns regarding the use of yttrium-alloyed magnesium implants, especially in pediatric patients.

  18. A wirelessly controlled implantable LED system for deep brain optogenetic stimulation

    Science.gov (United States)

    Rossi, Mark A.; Go, Vinson; Murphy, Tracy; Fu, Quanhai; Morizio, James; Yin, Henry H.

    2015-01-01

    In recent years optogenetics has rapidly become an essential technique in neuroscience. Its temporal and spatial specificity, combined with efficacy in manipulating neuronal activity, are especially useful in studying the behavior of awake behaving animals. Conventional optogenetics, however, requires the use of lasers and optic fibers, which can place considerable restrictions on behavior. Here we combined a wirelessly controlled interface and small implantable light-emitting diode (LED) that allows flexible and precise placement of light source to illuminate any brain area. We tested this wireless LED system in vivo, in transgenic mice expressing channelrhodopsin-2 in striatonigral neurons expressing D1-like dopamine receptors. In all mice tested, we were able to elicit movements reliably. The frequency of twitches induced by high power stimulation is proportional to the frequency of stimulation. At lower power, contraversive turning was observed. Moreover, the implanted LED remains effective over 50 days after surgery, demonstrating the long-term stability of the light source. Our results show that the wireless LED system can be used to manipulate neural activity chronically in behaving mice without impeding natural movements. PMID:25713516

  19. [A totally implantable venous access device. Implantation in general or local anaesthesia? A retrospective cost analysis].

    Science.gov (United States)

    Schuld, J; Richter, S; Moussavian, M R; Kollmar, O; Schilling, M K

    2009-08-01

    Implantation of venous access port systems can be performed in local or general anesthesia. In spite of the increasing rate of interventionally implanted systems, the surgical cut-down represents a safe alternative. Thus, the question arises whether--in context to the increasing health-economic pressure--open implantation in general anesthesia is still a feasible alternative to implantation in local anesthesia regarding OR efficiency and costs. In a retrospective analysis, 993 patients receiving a totally implantable venous access device between 2001 and 2007 were evaluated regarding OR utilization, turnover times, intraoperative data and costs. Implantations in local (LA) and general anesthesia (GA) were compared. GA was performed in 762 cases (76.6 %), LA was performed in 231 patients (23.3 %). Mean operation time was similar in both groups (LA 47.27 +/- 1.40 min vs. GA 45.41 +/- 0.75 min, p = 0.244). Patients receiving local anesthesia had a significantly shorter stay in the OR unit (LA 95.9 +/- 1.78 min vs. GA 105.92 +/- 0.92 min; p cut (LA 39.57 +/- 0.69 min vs. GA 50.46 +/- 0.52 min; p material costs were significantly lower in the LA group compared with the GA group (LA: 400.72 +/- 8.25 euro vs. GA: 482.86 +/- 6.23 euro; p systems in local anesthesia is superior in comparison to the implantation under general anesthesia regarding procedural times in the OR unit and costs. With the same operation duration, but less personnel and material expenditure, implantation in local anesthesia offers a potential economic advantage by permitting faster changing times. Implantation in GA only should be performed at a special request by the patient or in difficult venous conditions. Georg Thieme Verlag Stuttgart.New York.

  20. A two-microphone noise reduction system for cochlear implant users with nearby microphones. Part II: Performance Evaluation

    OpenAIRE

    Kompis, Martin; Bertram, Matthias; Senn, Pascal; Müller, Joachim; Pelizzone, Marco; Häusler, Rudolf

    2008-01-01

    Users of cochlear implants (auditory aids, which stimulate the auditory nerve electrically at the inner ear) often suffer from poor speech understanding in noise. We evaluate a small (intermicrophone distance 7 mm) and computationally inexpensive adaptive noise reduction system suitable for behind-the-ear cochlear implant speech processors. The system is evaluated in simulated and real, anechoic and reverberant environments. Results from simulations show improvements of 3.4 to 9.3 dB in signa...

  1. Sacroiliac joint stability: Finite element analysis of implant number, orientation, and superior implant length.

    Science.gov (United States)

    Lindsey, Derek P; Kiapour, Ali; Yerby, Scott A; Goel, Vijay K

    2018-03-18

    To analyze how various implants placement variables affect sacroiliac (SI) joint range of motion. An experimentally validated finite element model of the lumbar spine and pelvis was used to simulate a fusion of the SI joint using various placement configurations of triangular implants (iFuse Implant System ® ). Placement configurations were varied by changing implant orientation, superior implant length, and number of implants. The range of motion of the SI joint was calculated using a constant moment of 10 N-m with a follower load of 400 N. The changes in motion were compared between the treatment groups to assess how the different variables affected the overall motion of the SI joint. Transarticular placement of 3 implants with superior implants that end in the middle of the sacrum resulted in the greatest reduction in range of motion (flexion/extension = 73%, lateral bending = 42%, axial rotation = 72%). The range of motions of the SI joints were reduced with use of transarticular orientation (9%-18%) when compared with an inline orientation. The use of a superior implant that ended mid-sacrum resulted in median reductions of (8%-14%) when compared with a superior implant that ended in the middle of the ala. Reducing the number of implants, resulted in increased SI joint range of motions for the 1 and 2 implant models of 29%-133% and 2%-39%, respectively, when compared with the 3 implant model. Using a validated finite element model we demonstrated that placement of 3 implants across the SI joint using a transarticular orientation with superior implant reaching the sacral midline resulted in the most stable construct. Additional clinical studies may be required to confirm these results.

  2. Variable-temperature sample system for ion implantation at -192 to +5000C

    International Nuclear Information System (INIS)

    Fuller, C.T.

    1978-04-01

    A variable-temperature sample system based on exchange-gas coupling was developed for ion-implantation use. The sample temperature can be controlled from -192 0 C to +500 0 C with rapid cooling. The system also has provisions for focusing and alignment of the ion beam, electron suppression, temperature monitoring, sample current measuring, and cryo-shielding. Design considerations and operating characteristics are discussed. 5 figures

  3. Radioactive implants for medical applications; Radioaktive Implantate fuer medizinische Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, M.

    2008-07-01

    The long-term success of surgery is often diminished by excessive wound healing, which makes another intervention necessary. Locally applied radionuclides with short range radiation can prevent such benign hyperproliferation. As pure electron emitter with a half-life of 14.3 days and a mean energy of 694.9 keV (E{sub max}=1710.48 keV) {sup 32}P is a suitable radionuclide which can be produced from the stable {sup 31}P by the capture of thermal neutrons (1 x 10{sup 14} /s/cm{sup 2}) in a nuclear reactor. After a typical irradiation time (14 days) the ratio of {sup 32}P to {sup 31}P is 1.4 x 10{sup -5} to 1. Implants made of polymer and/or bioabsorbable material functioning as a carrier of the radioactive emitter allow - as opposed to metallic implants - for new applications for this type of radiotherapy. In this thesis a manufacturing method for previously not available organic, radioactive implants has been developed and a corresponding dosimetry system has been established. By means of ion implantation, {sup 32}P ions with up to 180 keV can be shot some 100 nm deep into organic implant materials. For a typical dose (15 Gy over 7 days, 1 mm distance from the implant) an activity of 75 kBq is needed corresponding to 1.3 x 10{sup 11} {sup 32}P ions. The sputter ion gun, which has been optimized for this application, creates an ion beam with high beam current (> 14 {mu}A P{sup -}) and low emittance (< 4 {pi} mm mrad {radical}(MeV)). Because of the good beam quality also small implants (<1 mm{sup 2}) can be manufactured with high efficiency. The unintentionally co-implanted portion of molecules and nuclides of the same mass (e.g. {sup 31}PH, {sup 16}O{sub 2} and {sup 32}S) could be reduced from approximately 500 to 50 by an improvement of the isotope selection at {sup 32}P beam creation. Hence, in comparison with the best hitherto existing implantation methods, the radiation dose of the implant could be reduced by an order of magnitude. With regard to the beta

  4. Group D. Initiator paper. Implants--peri-implant (hard and soft tissue) interactions in health and disease: the impact of explosion of implant manufacturers.

    Science.gov (United States)

    Ivanovski, Saso

    2015-01-01

    1. The best-documented implants have a threaded solid screw-type design and are manufactured from commercially pure (grade IV) titanium. There is good evidence to support implants ≥ 6 mm in length, and ≥ 3 mm in diameter. 2. Integrity of the seal between the abutment and the implant is important for several reasons, including minimization of mechanical and biological complications and maintaining marginal bone levels. Although the ideal design features of the implant-abutment connection have not been determined, an internal connection, micro-grooves at the implant collar, and horizontal offset of the implant-abutment junction (platform switch) appear to impart favorable properties. 3. Implants with moderately rough implant surfaces provide advantages over machined surfaces in terms of the speed and extent of osseointegration. While the favorable performances of both minimally and moderately rough surfaces are supported by long-term data, moderately rough surfaces provide superior outcomes in compromised sites, such as the posterior maxilla. 4. Although plaque is critical in the progression of peri-implantitis, the disease has a multi-factorial aetiology, and may be influenced by poor integrity of the abutment/implant connection. Iatrogenic factors, such as the introduction of a foreign body. (e.g., cement) below the mucosal margin, can be important contributors. 5. Clinicians should exercise caution when using a particular implant system, ensuring that the implant design is appropriate and supported by scientific evidence. Central to this is access to and participation in quality education on the impact that implant characteristics can have on clinical outcomes. Caution should be exercised in utilizing non-genuine restorative componentry that may lead to a poor implant-abutment fit and subsequent technical and biological complications.

  5. Short Implants: New Horizon in Implant Dentistry.

    Science.gov (United States)

    Jain, Neha; Gulati, Manisha; Garg, Meenu; Pathak, Chetan

    2016-09-01

    The choice of implant length is an essential factor in deciding the survival rates of these implants and the overall success of the prosthesis. Placing an implant in the posterior part of the maxilla and mandible has always been very critical due to poor bone quality and quantity. Long implants can be placed in association with complex surgical procedures such as sinus lift and bone augmentation. These techniques are associated with higher cost, increased treatment time and greater morbidity. Hence, there is need for a less invasive treatment option in areas of poor bone quantity and quality. Data related to survival rates of short implants, their design and prosthetic considerations has been compiled and structured in this manuscript with emphasis on the indications, advantages of short implants and critical biomechanical factors to be taken into consideration when choosing to place them. Studies have shown that comparable success rates can be achieved with short implants as those with long implants by decreasing the lateral forces to the prosthesis, eliminating cantilevers, increasing implant surface area and improving implant to abutment connection. Short implants can be considered as an effective treatment alternative in resorbed ridges. Short implants can be considered as a viable treatment option in atrophic ridge cases in order to avoid complex surgical procedures required to place long implants. With improvement in the implant surface geometry and surface texture, there is an increase in the bone implant contact area which provides a good primary stability during osseo-integration.

  6. Optimization of dental implantation

    Science.gov (United States)

    Dol, Aleksandr V.; Ivanov, Dmitriy V.

    2017-02-01

    Modern dentistry can not exist without dental implantation. This work is devoted to study of the "bone-implant" system and to optimization of dental prostheses installation. Modern non-invasive methods such as MRI an 3D-scanning as well as numerical calculations and 3D-prototyping allow to optimize all of stages of dental prosthetics. An integrated approach to the planning of implant surgery can significantly reduce the risk of complications in the first few days after treatment, and throughout the period of operation of the prosthesis.

  7. Symmetric Encryption Relying on Chaotic Henon System for Secure Hardware-Friendly Wireless Communication of Implantable Medical Systems

    Directory of Open Access Journals (Sweden)

    Taha Belkhouja

    2018-05-01

    Full Text Available Healthcare remote devices are recognized as a promising technology for treating health related issues. Among them are the wireless Implantable Medical Devices (IMDs: These electronic devices are manufactured to treat, monitor, support or replace defected vital organs while being implanted in the human body. Thus, they play a critical role in healing and even saving lives. Current IMDs research trends concentrate on their medical reliability. However, deploying wireless technology in such applications without considering security measures may offer adversaries an easy way to compromise them. With the aim to secure these devices, we explore a new scheme that creates symmetric encryption keys to encrypt the wireless communication portion. We will rely on chaotic systems to obtain a synchronized Pseudo-Random key. The latter will be generated separately in the system in such a way that avoids a wireless key exchange, thus protecting patients from the key theft. Once the key is defined, a simple encryption system that we propose in this paper will be used. We analyze the performance of this system from a cryptographic point of view to ensure that it offers a better safety and protection for patients.

  8. Influence of Palatal Coverage and Implant Distribution on Implant Strain in Maxillary Implant Overdentures.

    Science.gov (United States)

    Takahashi, Toshihito; Gonda, Tomoya; Mizuno, Yoko; Fujinami, Yozo; Maeda, Yoshinobu

    2016-01-01

    Maxillary implant overdentures are often used in clinical practice. However, there is no agreement or established guidelines regarding prosthetic design or optimal implant placement configuration. The purpose of this study was to examine the influence of palatal coverage and implant number and distribution in relation to impact strain under maxillary implant overdentures. A maxillary edentulous model with implants and experimental overdentures with and without palatal coverage was fabricated. Four strain gauges were attached to each implant, and they were positioned in the anterior, premolar, and molar areas. A vertical occlusal load of 98 N was applied through a mandibular complete denture, and the implant strains were compared using one-way analysis of variance (P = .05). The palatolabial strain was much higher on anterior implants than on other implants in both denture types. Although there was no significant difference between the strain under dentures with and without palatal coverage, palateless dentures tended to result in higher implant strain than dentures with palatal coverage. Dentures supported by only two implants registered higher strain than those supported by four or six implants. Implants under palateless dentures registered higher strain than those under dentures with palatal coverage. Anterior implants exhibited higher palatolabial strain than other implants regardless of palatal coverage and implant configuration; it is therefore recommended that maxillary implant overdentures should be supported by six implants with support extending to the distal end of the arch.

  9. An economic evaluation of maxillary implant overdentures based on six vs. four implants.

    Science.gov (United States)

    Listl, Stefan; Fischer, Leonhard; Giannakopoulos, Nikolaos Nikitas

    2014-08-18

    The purpose of the present study was to assess the value for money achieved by bar-retained implant overdentures based on six implants compared with four implants as treatment alternatives for the edentulous maxilla. A Markov decision tree model was constructed and populated with parameter estimates for implant and denture failure as well as patient-centred health outcomes as available from recent literature. The decision scenario was modelled within a ten year time horizon and relied on cost reimbursement regulations of the German health care system. The cost-effectiveness threshold was identified above which the six-implant solution is preferable over the four-implant solution. Uncertainties regarding input parameters were incorporated via one-way and probabilistic sensitivity analysis based on Monte-Carlo simulation. Within a base case scenario of average treatment complexity, the cost-effectiveness threshold was identified to be 17,564 € per year of denture satisfaction gained above of which the alternative with six implants is preferable over treatment including four implants. Sensitivity analysis yielded that, depending on the specification of model input parameters such as patients' denture satisfaction, the respective cost-effectiveness threshold varies substantially. The results of the present study suggest that bar-retained maxillary overdentures based on six implants provide better patient satisfaction than bar-retained overdentures based on four implants but are considerably more expensive. Final judgements about value for money require more comprehensive clinical evidence including patient-centred health outcomes.

  10. Anterior cruciate ligament reconstruction with 4-strand hamstring autograft and accelerated rehabilitation: a 10-year prospective study on clinical results, knee osteoarthritis and its predictors.

    Science.gov (United States)

    Janssen, Rob P A; du Mée, Arthur W F; van Valkenburg, Juliette; Sala, Harm A G M; Tseng, Carroll M

    2013-09-01

    Analysis of long-term clinical and radiological outcomes after anterior cruciate ligament (ACL) reconstruction with special attention to knee osteoarthritis and its predictors. A prospective, consecutive case series of 100 patients. Arthroscopic transtibial ACL reconstruction was performed using 4-strand hamstring tendon autografts with a standardized accelerated rehabilitation protocol. Analysis was performed preoperatively and 10 years postoperatively. Clinical examination included Lysholm and Tegner scores, IKDC, KT-1000 testing (MEDmetric Co., San Diego, CA, USA) and leg circumference measurements. Radiological evaluation included AP weight bearing, lateral knee, Rosenberg and sky view X-rays. Radiological classifications were according to Ahlbäck and Kellgren & Lawrence. Statistical analysis included univariate and multivariate logistic regressions. RESULTS CLINICAL OUTCOME: A significant improvement (p test, IKDC score and one-leg hop test. A pivot shift phenomenon (glide) was still present in 43 (50%) patients and correlated with lower levels of activity (p test. Transtibial ACL reconstruction with 4-strand hamstring autograft and accelerated rehabilitation restored anteroposterior knee stability. Clinical parameters and patient satisfaction improved significantly. At 10-year follow-up, radiological signs of OA were present in 53.5 % of the subjects. Risk factors for OA were meniscectomy prior to or at the time of ACL reconstruction and chondral lesions at the time of ACL reconstruction. II.

  11. Three-Dimensional Electroanatomic Mapping System-Enhanced Cardiac Resynchronization Therapy Device Implantation: Results From a Multicenter Registry.

    Science.gov (United States)

    Del Greco, Maurizio; Maines, Massimiliano; Marini, Massimiliano; Colella, Andrea; Zecchin, Massimo; Vitali-Serdoz, Laura; Blandino, Alessandro; Barbonaglia, Lorella; Allocca, Giuseppe; Mureddu, Roberto; Marenna, Biondino; Rossi, Paolo; Vaccari, Diego; Chianca, Roberto; Indiani, Stefano; DI Matteo, Irene; Angheben, Carlo; Zorzi, Alessandro

    2017-01-01

    Cardiac resynchronization therapy (CRT) device implantation guided by an electroanatomic mapping system (EAMS) is an emerging technique that may reduce fluoroscopy and angiography use and provide information on coronary sinus (CS) electrical activation. We evaluated the outcome of the EAMS-guided CRT implantation technique in a multicenter registry. During the period 2011-2014 we enrolled 125 patients (80% males, age 74 [71-77] years) who underwent CRT implantation by using the EnSite system to create geometric models of the patient's cardiac chambers, build activation mapping of the CS, and guide leads positioning. Two hundred and fifty patients undergoing traditional CRT implantation served as controls. Success and complication rates, fluoroscopy and total procedure times in the overall study population and according to center experience were collected. Centers that performed ≥10 were defined as highly experienced. Left ventricular lead implantation was successful in 122 (98%) cases and 242 (97%) controls (P = 0.76). Median fluoroscopy time was 4.1 (0.3-10.4) minutes in cases versus 16 (11-26) minutes in controls (P < 0.001). Coronary sinus angiography was performed in 33 (26%) cases and 208 (83%) controls (P < 0.001). Complications occurred in 5 (4%) cases and 17 (7%) controls (P = 0.28). Median fluoroscopy time (median 11 minutes vs. 3 minutes, P < 0.001) and CS angiography rate (55% vs. 21%, P < 0.001) were significantly higher in low experienced centers, while success rate and complications rate were similar. EAMS-guided CRT implantation proved safe and effective in both high- and low-experienced centers and allowed to reduce fluoroscopy use by ≈75% and angiography rate by ≈70%. © 2016 Wiley Periodicals, Inc.

  12. Implantation doping of GaN

    International Nuclear Information System (INIS)

    Zolper, J.C.

    1996-01-01

    Ion implantation has played an enabling role in the realization of many high performance photonic and electronic devices in mature semiconductor materials systems such as Si and GaAs. This can also be expected to be the case in III-Nitride based devices as the material quality continues to improve. This paper reviews the progress in ion implantation processing of the III-Nitride materials, namely, GaN, AlN, InN and their alloys. Details are presented of the successful demonstrations of implant isolation as well as n- and p-type implantation doping of GaN. Implant doping has required activation annealing at temperatures in excess of 1,000 C. The nature of the implantation induced damage and its response to annealing is addressed using Rutherford Backscattering. Finally, results are given for the first demonstration of a GaN device fabricated using ion implantation doping, a GaN junction field effect transistor (JFET)

  13. Different encapsulation strategies for implanted electronics

    Directory of Open Access Journals (Sweden)

    Winkler Sebastian

    2017-09-01

    Full Text Available Recent advancements in implant technology include increasing application of electronic systems in the human body. Hermetic encapsulation of electronic components is necessary, specific implant functions and body environments must be considered. Additional functions such as wireless communication systems require specialized technical solutions for the encapsulation.

  14. Open-Wedge High Tibial Osteotomy: RCT 2 Years RSA Follow-Up.

    Science.gov (United States)

    Lind-Hansen, Thomas Bruno; Lind, Martin Carøe; Nielsen, Poul Torben; Laursen, Mogens Berg

    2016-11-01

    We investigated the influence of three different bone grafting materials on stability and clinical outcome of the healing open-wedge high tibial osteotomy (OW-HTO) with immediate partial weight bearing. A total of 45 (3 × 15) patients were randomized to injectable calcium phosphate cement (Calcibon; Biomet-Merck Biomaterials GmbH, Darmstadt, Germany), local bone autograft, or iliac crest autograft. Stability of the bony healing was evaluated with radiostereometric analysis (RSA) up to 24 months postoperatively. Clinical outcome was evaluated with the knee injury and osteoarthritis outcome score (KOOS). RSA revealed translations and rotations close to zero regardless of bone grafting material, with no statistically significant differences between the groups. Clinically, the Calcibon group had lower quality of life KOOS subscore at 2 years follow-up. We conclude that with a stable implant and 6 weeks of partial weight bearing, local autografting is sufficient to achieve solid bone consolidation following OW-HTO. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  15. Systemic levels of metallic ions released from orthodontic mini-implants.

    Science.gov (United States)

    de Morais, Liliane Siqueira; Serra, Glaucio Guimarães; Albuquerque Palermo, Elisabete Fernandes; Andrade, Leonardo Rodrigues; Müller, Carlos Alberto; Meyers, Marc André; Elias, Carlos Nelson

    2009-04-01

    Orthodontic mini-implants are a potential source of metallic ions to the human body because of the corrosion of titanium (Ti) alloy in body fluids. The purpose of this study was to gauge the concentration of Ti, aluminum (Al), and vanadium (V), as a function of time, in the kidneys, livers, and lungs of rabbits that had Ti-6Al-4V alloy orthodontic mini-implants placed in their tibia. Twenty-three New Zealand rabbits were randomly divided into 4 groups: control, 1 week, 4 weeks, and 12 weeks. Four orthodontic mini-implants were placed in the left proximal tibia of 18 rabbits. Five control rabbits had no orthodontic mini-implants. After 1, 4, and 12 weeks, the rabbits were killed, and the selected tissues were extracted and prepared for analysis by graphite furnace atomic absorption spectrophotometry. Low amounts of Ti, Al, and V were detectable in the 1-week, 4-weeks, and 12-weeks groups, confirming that release of these metals from the mini-implants occurs, with diffusion and accumulation in remote organs. Despite the tendency of ion release when using the Ti alloy as orthodontic mini-implants, the amounts of metals detected were significantly below the average intake of these elements through food and drink and did not reach toxic concentrations.

  16. Percutaneous implantation of intra-arterial port system for regional drug infusion: results and complications in 110 cases

    International Nuclear Information System (INIS)

    Won, Je Hwan; Lee, Jong Hyuk; Ko, Kyung Hee; Won, Jong Yoon; Park, Sung Il; Lee, Do Yun; Kang, Byung Chul

    2000-01-01

    To investigate the feasibility and complications of a percutaneously implantable port system for regional drug infusion. For intra-arterial drug infusion, a 5.8 or 5-F pediatric venous port system was implanted in 110 patients with hepatocellular carcinoma (n=79), liver metastasis (n=16), gallbladder cancer (n=4), stomach cancer (n=3), pancreatic cancer (n=3), Burger's diseases mellitus (n=2), or lymphoma (n=1). All intra-arterial port implantations were performed percutaneously in an angiographic ward through the common femoral artery (n=98), left subclavian artery (n=10), or left superficial femoral artery (n=2). Complications were evaluated during the follow-up period, which ranged from 21 to 530 (mean, 163) days. The technical success rate for percutaneous implantation of the system was 97.3% (107 of 110 patients). The tips of the port catheter were located in the common hepatic artery (n=34), proper hepatic artery (n=49), right hepatic artery quick resulthepatic artery (n=1), descending aorta at T9 level (n=10), left popliteal artery (n=2), right external iliac artery (n=1), left external iliac artery (n=1), or left deep femoral artery (n=1). Complications were encountered in 24 patients (22.4%), namely chamber site infection (n=7), catheter dislodgement (n=7), catheter occlusion (n=3), migration of coil (n=2), disconnection between chamber and catheter (n=1), kinking of catheter (n=1), arterial occlusion (n=1), necrosis of overlying skin (n=1), and leakage around port chamber (n=1). Outcomes of complications included removal of port systems or cessation of therapy in 12 cases (11.2%), correction of catheter location using a guide wire in five (4.7%), thrombolysis with urokinase in three (2.8%), and straightening using a snare in one (0.9%). In three patients, the port system was used without reintervention. Percutaneous implantation of an intra-arterial port system showed a high technical success rate and a low rate of serious complications. The method may be

  17. Local and systemic changes associated with long-term, percutaneous, static implantation with titanium alloys in rhesus macaques (Macaca mulatta)

    Energy Technology Data Exchange (ETDEWEB)

    Frydman, Galit F.; Marini, Robert P.; Bakthavatchalu, Vasudevan; Biddle, Kathleen; Muthupalani, Sureshkumar; Vanderburg, Charles R.; Lai, Barry; Bendapudi, Pavan K.; Tompkins, Ronald G.; Fox, James G.

    2017-04-01

    Metal alloys are frequently used as implant materials in veterinary medicine. Recent studies suggest that many types of metal alloys may induce both local and systemic inflammatory responses. In this study, 37 rhesus macaques with long-term skull-anchored percutaneous titanium alloy implants (0-14 years duration) were evaluated for changes in their hematology, coagulation and serum chemistry profiles. Negative controls (n=28) did not have implants. All of the implanted animals were on IACUC-approved protocols and were not implanted for the purpose of this study. Animals with implants had significantly higher plasma D-dimer and lower antithrombin III concentrations compared with nonimplanted animals (p-values < 0.05). Additionally, animals with implants had significantly higher globulin, and lower albumin and calcium concentrations compared with nonimplanted animals (p-values < 0.05). Many of these changes were positively correlated with duration of implantation as well as the number of implants. Chronic bacterial infection was observed on the skin around many of the implant sites, and within deeper tissues. Representative histopathology around the implant site of two implanted animals revealed chronic suppurative to pyogranulomatous inflammation extending from the skin to the dura mater. X-ray fluorescence microscopy of tissue biopsies from the implant site of the same two animals revealed significant increases in free metal ions within the tissue, including titanium and iron. Free metal ions persisted in the tissues up to 6 months postexplant. These results suggest that long-term skull-anchored percutaneous titanium alloy implants results in localized inflammation, chronic infection, and leaching of metal ions into local tissues.

  18. Stent implantation into the tracheo-bronchial system in rabbits: histopathologic sequelae in bare metal vs. drug-eluting stents.

    Science.gov (United States)

    Sigler, Matthias; Klötzer, Julia; Quentin, Thomas; Paul, Thomas; Möller, Oliver

    2015-12-01

    Stent implantation into the tracheo-bronchial system may be life-saving in selected pediatric patients with otherwise intractable stenosis of the upper airways. Following implantation, significant tissue proliferation may occur, requiring re-interventions. We sought to evaluate the effect of immunosuppressive coating of the stents on the extent of tissue proliferation in an animal model. Bare metal and sirolimus-coated stents (Bx Sonic and Cypher Select, Johnson & Johnson, Cordis) were implanted into non-stenotic lower airways of New Zealand white rabbits (weight 3.1 to 4.8 kg). Three stents with sirolimus coating and six bare metal stents could be analyzed by means of histology and immunohistochemistry 12 months after implantation. On a macroscopic evaluation, all stents were partially covered with a considerable amount of whitish tissue. Histologically, these proliferations contained fiber-rich connective tissue and some fibromuscular cells without significant differences between both stent types. The superficial tissue layer was formed by typical respiratory epithelium and polygonal cells. Abundant lymphocyte infiltrations and moderate granulocyte infiltrations were found in both groups correspondingly, whereas foreign-body reaction was more pronounced around sirolimus-eluting stents. After stent implantation in the tracheo-bronchial system of rabbits, we found tissue reactions comparable to those seen after stent implantation into the vascular system. There was no difference between coated and uncoated stents with regard to quality and quantity of tissue proliferation. We found, however, a significantly different inflammatory reaction with a more pronounced foreign-body reaction in sirolimus-coated stents. In our small series, drug-eluting stents did not exhibit any benefit over bare metal stents in an experimental setting.

  19. A touch probe method of operating an implantable RFID tag for orthopedic implant identification.

    Science.gov (United States)

    Liu, Xiaoyu; Berger, J Lee; Ogirala, Ajay; Mickle, Marlin H

    2013-06-01

    The major problem in operating an implantable radio-frequency identification (RFID) tag embedded on an orthopedic implant is low efficiency because of metallic interference. To improve the efficiency, this paper proposes a method of operating an implantable passive RFID tag using a touch probe at 13.56 MHz. This technology relies on the electric field interaction between two pairs of electrodes, one being a part of the touch probe placed on the surface of tissue and the other being a part of the tag installed under the tissue. Compared with using a conventional RFID antenna such as a loop antenna, this method has a better performance in the near field operation range to reduce interference with the orthopedic implant. Properly matching the touch probe and the tag to the tissue and the implant reduces signal attenuation and increases the overall system efficiency. The experiments have shown that this method has a great performance in the near field transcutaneous operation and can be used for orthopedic implant identification.

  20. Design and optimization of a 3-coil resonance-based wireless power transfer system for biomedical implants

    KAUST Repository

    Yi, Ying

    2014-09-01

    This paper presents a resonance-based wireless power transfer system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. We theoretically analyzed the system and characterized it by measuring its inductance, self-resonant frequency, and quality factor Q. In our resonance-based wireless power transfer prototype, we proposed a 3-coil system, using two 15-mm radius implantable coils, with a resonance frequency of 6.76MHz. This system can effectively transfer power for a distance of up to 50mm. Moreover, our proposed 3-coil system can achieve a high Q-factor and has a comparable power transfer efficiency (PTE) to previously reported works about 3-coil and 4-coil systems. The experimental PTE can achieve 82.4% at a separation distance of 20mm and more than 10% PTE at a distance of 40mm.

  1. Design and optimization of a 3-coil resonance-based wireless power transfer system for biomedical implants

    KAUST Repository

    Yi, Ying; Buttner, Ulrich; Fan, Yiqiang; Foulds, Ian G.

    2014-01-01

    This paper presents a resonance-based wireless power transfer system using a single layer of inductor coil windings, in a pancake configuration, in order to obtain a compact system for implantable electronic applications. We theoretically analyzed the system and characterized it by measuring its inductance, self-resonant frequency, and quality factor Q. In our resonance-based wireless power transfer prototype, we proposed a 3-coil system, using two 15-mm radius implantable coils, with a resonance frequency of 6.76MHz. This system can effectively transfer power for a distance of up to 50mm. Moreover, our proposed 3-coil system can achieve a high Q-factor and has a comparable power transfer efficiency (PTE) to previously reported works about 3-coil and 4-coil systems. The experimental PTE can achieve 82.4% at a separation distance of 20mm and more than 10% PTE at a distance of 40mm.

  2. Automated dental implantation using image-guided robotics: registration results.

    Science.gov (United States)

    Sun, Xiaoyan; McKenzie, Frederic D; Bawab, Sebastian; Li, Jiang; Yoon, Yongki; Huang, Jen-K

    2011-09-01

    One of the most important factors affecting the outcome of dental implantation is the accurate insertion of the implant into the patient's jaw bone, which requires a high degree of anatomical accuracy. With the accuracy and stability of robots, image-guided robotics is expected to provide more reliable and successful outcomes for dental implantation. Here, we proposed the use of a robot for drilling the implant site in preparation for the insertion of the implant. An image-guided robotic system for automated dental implantation is described in this paper. Patient-specific 3D models are reconstructed from preoperative Cone-beam CT images, and implantation planning is performed with these virtual models. A two-step registration procedure is applied to transform the preoperative plan of the implant insertion into intra-operative operations of the robot with the help of a Coordinate Measurement Machine (CMM). Experiments are carried out with a phantom that is generated from the patient-specific 3D model. Fiducial Registration Error (FRE) and Target Registration Error (TRE) values are calculated to evaluate the accuracy of the registration procedure. FRE values are less than 0.30 mm. Final TRE values after the two-step registration are 1.42 ± 0.70 mm (N = 5). The registration results of an automated dental implantation system using image-guided robotics are reported in this paper. Phantom experiments show that the practice of robot in the dental implantation is feasible and the system accuracy is comparable to other similar systems for dental implantation.

  3. Spectral-Temporal Modulated Ripple Discrimination by Children With Cochlear Implants.

    Science.gov (United States)

    Landsberger, David M; Padilla, Monica; Martinez, Amy S; Eisenberg, Laurie S

    A postlingually implanted adult typically develops hearing with an intact auditory system, followed by periods of deafness (or near deafness) and adaptation to the implant. For an early implanted child whose brain is highly plastic, the auditory system matures with consistent input from a cochlear implant. It is likely that the auditory system of early implanted cochlear implant users is fundamentally different than postlingually implanted adults. The purpose of this study is to compare the basic psychophysical capabilities and limitations of these two populations on a spectral resolution task to determine potential effects of early deprivation and plasticity. Performance on a spectral resolution task (Spectral-temporally Modulated Ripple Test [SMRT]) was measured for 20 bilaterally implanted, prelingually deafened children (between 5 and 13 years of age) and 20 hearing children within the same age range. Additionally, 15 bilaterally implanted, postlingually deafened adults, and 10 hearing adults were tested on the same task. Cochlear implant users (adults and children) were tested bilaterally, and with each ear alone. Hearing listeners (adults and children) were tested with the unprocessed SMRT and with a vocoded version that simulates an 8-channel cochlear implant. For children with normal hearing, a positive correlation was found between age and SMRT score for both the unprocessed and vocoded versions. Older hearing children performed similarly to hearing adults in both the unprocessed and vocoded test conditions. However, for children with cochlear implants, no significant relationship was found between SMRT score and chronological age, age at implantation, or years of implant experience. Performance by children with cochlear implants was poorer than performance by cochlear implanted adults. It was also found that children implanted sequentially tended to have better scores with the first implant compared with the second implant. This difference was not

  4. Maxillary Three-Implant Overdentures Opposing Mandibular Two-Implant Overdentures: 10-Year Surgical Outcomes of a Randomized Controlled Trial.

    Science.gov (United States)

    Ma, Sunyoung; Tawse-Smith, Andrew; De Silva, Rohana K; Atieh, Momen A; Alsabeeha, Nabeel H M; Payne, Alan G T

    2016-06-01

    The surgical placement of four maxillary implants for overdentures may not be obligatory when opposing mandibular two-implant overdentures. To determine 10-year surgical outcomes and implant success of three narrow diameter implants in edentulous maxillae with conventional loading. Forty participants with mandibular two-implant overdentures were randomly allocated for surgery for maxillary overdentures. Using osteotomes, three implants of similar systems were placed with a one-stage procedure and 12-week loading with splinted and unsplinted prosthodontic designs. Marginal bone and stability measurements were done at surgery, 12 weeks, 1-, 2-, 5-, 7-, 10 years. One hundred seventeen implants were placed in 39 participants, with 35 being seen at 1 year; 29 at 2 years; 28 at 5 years; 26 at 7 years; and 23 (59%) at 10 years. Marginal bone loss was 1.35 mm between surgery and 12 weeks; 0.36 mm between 12 weeks and 1 year; 0.48 mm between 1 and 5 years; and 0.22 mm between 5 and 10 years. Implant stability quotients were 56.05, 57.54, 60.88, 58.80, 61.17 at surgery, 12 weeks, 1 year, 5 years, and 10 years. Four-field tables by implant showed success rates of 82% at 1 year; 69.2% at 2 years; 66.7% at 5 years; 61.5% at 7 years; 51.3% at 10 years. Data showed no differences between surgical technique, systems, or prosthodontic designs. Surgical placement with osteotomes of three narrow diameter implants for maxillary overdentures, opposing mandibular two-implant overdentures, is an acceptable approach, subject to strict patient selection. Implant success is independent of prosthodontic design. © 2015 Wiley Periodicals, Inc.

  5. Reliable and energy-efficient communications for wireless biomedical implant systems.

    Science.gov (United States)

    Ntouni, Georgia D; Lioumpas, Athanasios S; Nikita, Konstantina S

    2014-11-01

    Implant devices are used to measure biological parameters and transmit their results to remote off-body devices. As implants are characterized by strict requirements on size, reliability, and power consumption, applying the concept of cooperative communications to wireless body area networks offers several benefits. In this paper, we aim to minimize the power consumption of the implant device by utilizing on-body wearable devices, while providing the necessary reliability in terms of outage probability and bit error rate. Taking into account realistic power considerations and wireless propagation environments based on the IEEE P802.l5 channel model, an exact theoretical analysis is conducted for evaluating several communication scenarios with respect to the position of the wearable device and the motion of the human body. The derived closed-form expressions are employed toward minimizing the required transmission power, subject to a minimum quality-of-service requirement. In this way, the complexity and power consumption are transferred from the implant device to the on-body relay, which is an efficient approach since they can be easily replaced, in contrast to the in-body implants.

  6. Impact of systemic diseases on oral health related quality of life after implant-prosthodontic rehabilitation

    Directory of Open Access Journals (Sweden)

    Tina Pretnar

    2014-08-01

    Full Text Available Background: Implant-prosthodontic rehabilitation improves oral health related quality of life (OHRQoL, but the presence of systemic diseases can also affect the well-being of an individual.The study was carried out to determine the relationship between systemic diseases and OHRQoL after implant-prosthodontic rehabilitation on the basis of psychometric testing by a standardized questionnaire »Oral Health Impact Profile« (OHIP.Methods: 130 patients, who received one to eight Ankylos® implants (on average 2.6 ± 1.8 were included in this retrospective study in which all aspects of the OHRQoL construct were evaluated with a Slovenian version of the OHIP questionnaire. Data on all present systemic diseases were obtained from the existing health records. Dental status and dental restorations were identified on the basis of orthopantomographic images.Results: The majority of subjects had a cardiovascular disease (N = 37; 28.5 %, followed by a headache (N = 15, 11.5 %, allergies and asthma (n = 13, 10 %, and a rheumatic disease (N = 11, 8.5 %. Only osteoporosis was statistically significantly related to OHRQoL after implant-prosthodontic rehabilitation (p = 0.024. The best multiple linear regression model for the summary score for the questionnaire »Oral Health Impact Profile« for Slovenia (OHIP, and taking into account gender and age as confounding factors, included the number of remaining teeth and the presence of osteoporosis (p = 0.003, adjusted R2 = 0.104.Conclusions: The total number of remaining teeth in the oral cavity (p = 0.031, the presence of osteoporosis (p = 0.024, and taking into account the subject’s gender and age, are the most important clinical factors that affect the functioning of the SGS as well as psychosocial behavior of the patients after an implant-prosthodontic rehabilitation (adjusted R2 = 0.104. Other systemic diseases (cardiovascular disease, headache, allergies and

  7. Determining Threshold Distance Providing Less Interference for Wireless Medical Implant Communication Systems in Coexisting Environments under Shadow Fading Conditions

    Directory of Open Access Journals (Sweden)

    Selman KULAÇ

    2017-08-01

    Full Text Available Important interference problems will be able to be encountered especially close areas to the hospitals where wireless implantable medical systems' communication traffic occurs heavily in near future. It is possible that these interferences could cause wireless implant devices to malfunction and harmful effects on patients. In this study, it is proposed to determine threshold distance in order to get less interference for wireless implantable medical systems under shadow fading conditions where MICS band and MetAids band users coexist intensely simultaneously. In this method, threshold power according to the \\cite{FCC} is pulled down by adding extra distance margin in order to minimize the interference effects to the MICS systems using confidence interval calculations. Because received signal strength just below the monitoring threshold power according to the \\cite{FCC} brings about much more interferences for the MICS systems even if listen-before-talk technique is applied.

  8. Clinical observation on fibrin glue technique in pterygium surgery performed with limbal autograft transplantation

    Directory of Open Access Journals (Sweden)

    Hui Liu

    2013-07-01

    Full Text Available AIM: To compare the efficiency and safety of fibrin glue to suture technique in pterygium surgery performed with limbal autograft.METHODS: A prospective randomized clinical trial was carried out in 60 eyes of 48 patients operated for primary nasal pterygium. Autologous limbal graft taken from the superotemporal limbus was used to cover the sclera after pterygium excision under local anesthesia with 2% lidocaine. In 22 cases(30 eyes, the transplant was attached to the sclera with a fibrin tissue adhesive(group 1and in 26 cases(30 eyeswith 10-0 Virgin silk sutures(group 2. Patients were followed up at least for 3 months. Time of operation, matching degree of graft and visual analogue scale(VASscore were mainly observed and recorded. RESULTS: Patient symptoms were significantly less and biomicroscopic findings were better in group 1. Pterygium recurrence was seen in 1 case of group 1, and 1 case of group 2. Average surgery time was shorter(PCONCLUSION: Using fibrin glue for graft fixation in pterygium surgery causes significantly less postoperative pain and shortens surgery time significantly.

  9. Impact of Different Surgeons on Dental Implant Failure.

    Science.gov (United States)

    Chrcanovic, Bruno Ramos; Kisch, Jenö; Albrektsson, Tomas; Wennerberg, Ann

    To assess the influence of several factors on the prevalence of dental implant failure, with special consideration of the placement of implants by different dental surgeons. This retrospective study is based on 2,670 patients who received 10,096 implants at one specialist clinic. Only the data of patients and implants treated by surgeons who had inserted a minimum of 200 implants at the clinic were included. Kaplan-Meier curves were stratified with respect to the individual surgeon. A generalized estimating equation (GEE) method was used to account for the fact that repeated observations (several implants) were placed in a single patient. The factors bone quantity, bone quality, implant location, implant surface, and implant system were analyzed with descriptive statistics separately for each individual surgeon. A total of 10 surgeons were eligible. The differences between the survival curves of each individual were statistically significant. The multivariate GEE model showed the following variables to be statistically significant: surgeon, bruxism, intake of antidepressants, location, implant length, and implant system. The surgeon with the highest absolute number of failures was also the one who inserted the most implants in sites of poor bone and used turned implants in most cases, whereas the surgeon with the lowest absolute number of failures used mainly modern implants. Separate survival analyses of turned and modern implants stratified for the individual surgeon showed statistically significant differences in cumulative survival. Different levels of failure incidence could be observed between the surgeons, occasionally reaching significant levels. Although a direct causal relationship could not be ascertained, the results of the present study suggest that the surgeons' technique, skills, and/or judgment may negatively influence implant survival rates.

  10. Dose perturbation in the presence of metallic implants: treatment planning system versus Monte Carlo simulations

    International Nuclear Information System (INIS)

    Wieslander, Elinore; Knoeoes, Tommy

    2003-01-01

    An increasing number of patients receiving radiation therapy have metallic implants such as hip prostheses. Therefore, beams are normally set up to avoid irradiation through the implant; however, this cannot always be accomplished. In such situations, knowledge of the accuracy of the used treatment planning system (TPS) is required. Two algorithms, the pencil beam (PB) and the collapsed cone (CC), are implemented in the studied TPS. Comparisons are made with Monte Carlo simulations for 6 and 18 MV. The studied materials are steel, CoCrMo, Orthinox(a stainless steel alloy and registered trademark of Stryker Corporation), TiAlV and Ti. Monte Carlo simulated depth dose curves and dose profiles are compared to CC and PB calculated data. The CC algorithm shows overall a better agreement with Monte Carlo than the PB algorithm. Thus, it is recommended to use the CC algorithm to get the most accurate dose calculation both for the planning target volume and for tissues adjacent to the implants when beams are set up to pass through implants

  11. Macro design morphology of endosseous dental implants.

    Science.gov (United States)

    Sahiwal, Indira G; Woody, Ronald D; Benson, Byron W; Guillen, Guillermo E

    2002-05-01

    The identification of dental implant bodies in patients without available records is a considerable problem due to increased patient mobility and to the large number of implant systems with different designs. The purpose of this study was to document the designs of selected implants to help clinicians identify these implants from their radiographic images. More than 50 implant manufacturers were contacted and asked to provide implants with dimensions as close as possible to 3.75 mm (diameter) x 10 mm (length). Forty-four implants were donated, separated into threaded and non-threaded categories, and further sorted into tapered and non-tapered categories. The implants were examined visually, and features on the entire circumference and length of each implant were recorded and categorized as coronal, midbody, or apical. A series of tables describe the 44 implants according to coronal, midbody, and apical features. The results of this project offer dentists basic knowledge of the design of selected dental implants. Such knowledge can aid the radiographic identification of these implants.

  12. Retention system for implant-supported dentures used by brazilian dentists who work in implant dentistry

    OpenAIRE

    Saturnino Aparecido Ramalho; Fábio Pontes Dantas

    2010-01-01

    Objective: To provide the dentists with support in the choice of the cement or screw type of retention for implant-supported dentures, according to the patient’s problem. Methods: An opinion questionnaire was applied to a sample of 468 participants, all dentists working in the field of Implant Dentistry, of whom 272 (58.1%) participated in the 4th International Congress of Osseointegration of APCD, held in São Paulo (SP) from 6 to 9 May 2004, 119 (25.4%) participated in the 2nd International ...

  13. Irradiation influence on Mylar and Makrofol induced by argon ions in a plasma immersion ion implantation system

    Energy Technology Data Exchange (ETDEWEB)

    Hassan, A. [Accelerators & Ion Sources Department, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Cairo (Egypt); El-Saftawy, A.A., E-mail: aama1978@yahoo.com [Accelerators & Ion Sources Department, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Cairo (Egypt); Aal, S.A. Abd El [Central Lab. for Elemental & Isotopic Analysis, Nuclear Research Center, Atomic Energy Authority, P.O. 13759, Cairo (Egypt); Ghazaly, M. El [Physiology Department, College of Medicine, Taif University, P.O. 888, Taif (Saudi Arabia); Physics Department, Faculty of Science, Zagazig University, P.O. 44519, Zagazig (Egypt)

    2015-08-30

    Highlights: • A home-built plasma immersion ion implantation system was tested in modifying surfaces. • Wettability modifications within the energy range 10 keV implantation are not investigated elsewhere, up to our knowledge. • The wettability of Mylar and Makrofol surface was enhanced by the dual effect of ion implantation and plasma treatment. • The improved wettability was found to depend on both surface roughness and chemistry. • The adhesive bonding and surface energy of the polymers are improved. - Abstract: Mylar and Makrofol polycarbonate polymers were irradiated by Ar ions in a plasma immersion ion implantation (PIII) system. The surface wettability of both polymers was investigated by employing the contact angle method. The measured contact angles were found to depend on the surface layer properties. Good wetting surfaces were found to depend not only on surface roughness but also on its chemistry that analyzed by Fourier transform infrared (FTIR) spectroscopy. Surfaces topography and roughness was investigated and correlated to their surface energy which studied with the aid of acid-base model for evaluating the improvement of surface wettability after irradiation. PIII improves polymers surface properties efficiently in a controllable way.

  14. Diagnostic Principles of Peri-Implantitis: a Systematic Review and Guidelines for Peri-Implantitis Diagnosis Proposal

    Directory of Open Access Journals (Sweden)

    Ausra Ramanauskaite

    2016-09-01

    Full Text Available Objectives: To review and summarize the literature concerning peri-implantitis diagnostic parameters and to propose guidelines for peri-implantitis diagnosis. Material and Methods: An electronic literature search was conducted of the MEDLINE (Ovid and EMBASE databases for articles published between 2011 and 2016. Sequential screening at the title/abstract and full-text levels was performed. Systematic reviews/guidelines of consensus conferences proposing classification or suggesting diagnostic parameters for peri-implantitis in the English language were included. The review was recorded on PROSPERO system with the code CRD42016033287. Results: The search resulted in 10 articles that met the inclusion criteria. Four were papers from consensus conferences, two recommended diagnostic guidelines, three proposed classification of peri-implantitis, and one suggested an index for implant success. The following parameters were suggested to be used for peri-implantitis diagnosis: pain, mobility, bleeding on probing, probing depth, suppuration/exudate, and radiographic bone loss. In all of the papers, different definitions of peri-implantitis or implant success, as well as different thresholds for the above mentioned clinical and radiographical parameters, were used. Current evidence rationale for the diagnosis of peri-implantitis and classification based on consecutive evaluation of soft-tissue conditions and the amount of bone loss were suggested. Conclusions: Currently there is no single uniform definition of peri-implantitis or the parameters that should be used. Rationale for diagnosis and prognosis of peri-implantitis as well as classification of the disease is proposed.

  15. [Technical feasibility of the implantation of a monorail stent system into the renal arteries without pre-dilatation].

    Science.gov (United States)

    Neumann, C; Gschwendtner, M; Karnel, F; Mair, J; Dorffner, G; Dorffner, R

    2005-01-01

    To evaluate the technical feasibility of the implantation of the monorail RX Herculink system into the renal arteries without pre-dilatation. Forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink stent. The mean grade of the stenosis was 83.8 %, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). In 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30 % were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 +/- 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 +/- 0.0. Implantation of the RX Herculink stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies.

  16. Laser-Modified Surface Enhances Osseointegration and Biomechanical Anchorage of Commercially Pure Titanium Implants for Bone-Anchored Hearing Systems

    Science.gov (United States)

    Omar, Omar; Simonsson, Hanna; Palmquist, Anders; Thomsen, Peter

    2016-01-01

    Osseointegrated implants inserted in the temporal bone are a vital component of bone-anchored hearing systems (BAHS). Despite low implant failure levels, early loading protocols and simplified procedures necessitate the application of implants which promote bone formation, bone bonding and biomechanical stability. Here, screw-shaped, commercially pure titanium implants were selectively laser ablated within the thread valley using an Nd:YAG laser to produce a microtopography with a superimposed nanotexture and a thickened surface oxide layer. State-of-the-art machined implants served as controls. After eight weeks’ implantation in rabbit tibiae, resonance frequency analysis (RFA) values increased from insertion to retrieval for both implant types, while removal torque (RTQ) measurements showed 153% higher biomechanical anchorage of the laser-modified implants. Comparably high bone area (BA) and bone-implant contact (BIC) were recorded for both implant types but with distinctly different failure patterns following biomechanical testing. Fracture lines appeared within the bone ~30–50 μm from the laser-modified surface, while separation occurred at the bone-implant interface for the machined surface. Strong correlations were found between RTQ and BIC and between RFA at retrieval and BA. In the endosteal threads, where all the bone had formed de novo, the extracellular matrix composition, the mineralised bone area and osteocyte densities were comparable for the two types of implant. Using resin cast etching, osteocyte canaliculi were observed directly approaching the laser-modified implant surface. Transmission electron microscopy showed canaliculi in close proximity to the laser-modified surface, in addition to a highly ordered arrangement of collagen fibrils aligned parallel to the implant surface contour. It is concluded that the physico-chemical surface properties of laser-modified surfaces (thicker oxide, micro- and nanoscale texture) promote bone bonding

  17. Repair of segmental bone defect using Totally Vitalized tissue engineered bone graft by a combined perfusion seeding and culture system.

    Directory of Open Access Journals (Sweden)

    Lin Wang

    Full Text Available BACKGROUND: The basic strategy to construct tissue engineered bone graft (TEBG is to combine osteoblastic cells with three dimensional (3D scaffold. Based on this strategy, we proposed the "Totally Vitalized TEBG" (TV-TEBG which was characterized by abundant and homogenously distributed cells with enhanced cell proliferation and differentiation and further investigated its biological performance in repairing segmental bone defect. METHODS: In this study, we constructed the TV-TEBG with the combination of customized flow perfusion seeding/culture system and β-tricalcium phosphate (β-TCP scaffold fabricated by Rapid Prototyping (RP technique. We systemically compared three kinds of TEBG constructed by perfusion seeding and perfusion culture (PSPC method, static seeding and perfusion culture (SSPC method, and static seeding and static culture (SSSC method for their in vitro performance and bone defect healing efficacy with a rabbit model. RESULTS: Our study has demonstrated that TEBG constructed by PSPC method exhibited better biological properties with higher daily D-glucose consumption, increased cell proliferation and differentiation, and better cell distribution, indicating the successful construction of TV-TEBG. After implanted into rabbit radius defects for 12 weeks, PSPC group exerted higher X-ray score close to autograft, much greater mechanical property evidenced by the biomechanical testing and significantly higher new bone formation as shown by histological analysis compared with the other two groups, and eventually obtained favorable healing efficacy of the segmental bone defect that was the closest to autograft transplantation. CONCLUSION: This study demonstrated the feasibility of TV-TEBG construction with combination of perfusion seeding, perfusion culture and RP technique which exerted excellent biological properties. The application of TV-TEBG may become a preferred candidate for segmental bone defect repair in orthopedic and

  18. Miniature Coplanar Implantable Antenna on Thin and Flexible Platform for Fully Wireless Intracranial Pressure Monitoring System

    Directory of Open Access Journals (Sweden)

    M. Waqas A. Khan

    2017-01-01

    Full Text Available Minimally invasive approach to intracranial pressure monitoring is desired for long-term diagnostics. The monitored pressure is transmitted outside the skull through an implant antenna. We present a new miniature (6 mm × 5 mm coplanar implant antenna and its integration on a sensor platform to establish a far-field data link for the sensor readout at distances of 0.5 to 1 meter. The implant antenna was developed using full-wave electromagnetic simulator and measured in a liquid phantom mimicking the dielectric properties of the human head. It achieved impedance reflection coefficient better than −10 dB from 2.38 GHz to 2.54 GHz which covers the targeted industrial, scientific, and medical band. Experiments resulted in an acceptable peak gain of approximately −23 dBi. The implant antenna was submerged in the liquid phantom and interfaced to a 0.5 mW voltage controlled oscillator. To verify the implant antenna performance as a part of the ICP monitoring system, we recorded the radiated signal strength using a spectrum analyzer. Using a half-wavelength dipole as the receiving antenna, we captured approximately −58.7 dBm signal at a distance of 1 m from the implant antenna which is well above for the reader with sensitivity of −80 dBm.

  19. Stress Distribution in Single Dental Implant System: Three-Dimensional Finite Element Analysis Based on an In Vitro Experimental Model.

    Science.gov (United States)

    Rezende, Carlos Eduardo Edwards; Chase-Diaz, Melody; Costa, Max Doria; Albarracin, Max Laurent; Paschoeto, Gabriela; Sousa, Edson Antonio Capello; Rubo, José Henrique; Borges, Ana Flávia Sanches

    2015-10-01

    This study aimed to analyze the stress distribution in single implant system and to evaluate the compatibility of an in vitro model with finite element (FE) model. The in vitro model consisted of Brånemark implant; multiunit set abutment of 5 mm height; metal-ceramic screw-retained crown, and polyurethane simulating the bone. Deformations were recorded in the peri-implant region in the mesial and distal aspects, after an axial 300 N load application at the center of the occlusal aspect of the crown, using strain gauges. This in vitro model was scanned with micro CT to design a three-dimensional FE model and the strains in the peri-implant bone region were registered to check the compatibility between both models. The FE model was used to evaluate stress distribution in different parts of the system. The values obtained from the in vitro model (20-587 με) and the finite element analysis (81-588 με) showed agreement among them. The highest stresses because of axial and oblique load, respectively were 5.83 and 40 MPa for the cortical bone, 55 and 1200 MPa for the implant, and 80 and 470 MPa for the abutment screw. The FE method proved to be effective for evaluating the deformation around single implant. Oblique loads lead to higher stress concentrations.

  20. Intra- and intersubject comparison of cochlear implant systems using the Esprit and the Tempo+ behind-the-ear speech processor.

    Science.gov (United States)

    Kompis, Martin; Jenk, Martin; Vischer, Mattheus W; Seifert, Eberhard; Häusler, Rudolf

    2002-12-01

    A patient with bilateral profound deafness was implanted with a Nucleus CI24M cochlear implant (CI) and used an Esprit behind-the-ear (BTE) speech processor. Thirteen months later, the implant had to be removed because of a cholesteatoma. As the same electrode could not be reinserted, a Medel combi40s CI was implanted in the same ear, and the patient used a Tempo+ BTE processor. After 1 year of use of the Combi40s/Tempo+ system, speech recognition was better and was rated better subjectively than with the CI24M/Esprit system. Speech recognition and subjective ratings were also assessed for two matched groups of nine CI users each, using either an Esprit or a Tempo+ processor. On average, speech recognition scores were higher for the group of Tempo+ users, but the difference was not statistically significant. Users of the Esprit processors rated their device higher in terms of cosmetic appearance and comfort of wearing.

  1. Influences of microgap and micromotion of implant-abutment interface on marginal bone loss around implant neck.

    Science.gov (United States)

    Liu, Yang; Wang, Jiawei

    2017-11-01

    To review the influences and clinical implications of micro-gap and micro-motion of implant-abutment interface on marginal bone loss around the neck of implant. Literatures were searched based on the following Keywords: implant-abutment interface/implant-abutment connection/implant-abutment conjunction, microgap, micromotion/micromovement, microleakage, and current control methods available. The papers were then screened through titles, abstracts, and full texts. A total of 83 studies were included in the literature review. Two-piece implant systems are widely used in clinics. However, the production error and masticatory load result in the presence of microgap and micromotion between the implant and the abutment, which directly or indirectly causes microleakage and mechanical damage. Consequently, the degrees of microgap and micromotion further increase, and marginal bone absorption finally occurs. We summarize the influences of microgap and micromotion at the implant-abutment interface on marginal bone loss around the neck of the implant. We also recommend some feasible methods to reduce their effect. Clinicians and patients should pay more attention to the mechanisms as well as the control methods of microgap and micromotion. To reduce the corresponding detriment to the implant marginal bone, suitable Morse taper or hybrid connection implants and platform switching abutments should be selected, as well as other potential methods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  2. Aspects of an automatic system of implants of radioactive seeds and anatomic object simulator for tests in prostate brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Leonardo S.M.; Braga, Viviane V.B.; Campos, Tarcísio P. R. de, E-mail: leonardosantiago.lsms@gmail.com, E-mail: vitoriabraga06@gmail.com, E-mail: tprcampos@yahoo.com.br [Universidade Federal de Minas Gerais (PCTN/UFMG), Belo Horizonte (Brazil). Pós-Graduação em Ciências e Técnicas Nucleares. Departamento de Engenharia Nuclear

    2017-07-01

    This work presents the state of the art of the research and development of an automatic radioactive seed implantation system (PSIS). PSIS may assist in the procedure of testing permanent implants in the prostate. These tests will be important in measurements of absorbed doses in the pelvic structures, involving the organs and tissues at risk to improve planning, seed positioning and dosimetry. The automated Prostate Seed Implant System (PSIS) has been designed to meet operational needs, which offers the freedom of positioning of the brachytherapy needle within the treatment area and ensures repeatability and fidelity to the planned treatment. Both the ultrasound probe and the seed implant needle are driven by step motors, Atmega microcontroller, bearings, aluminum shafts and a GUI (Graphical User Interface). Movement of both the probe and the needle holder was performed by fixed spindle on a threaded rod rushing to the step motors by a coupling. The step motors used to move the system consist of step motors used in CNC (Computer Numeric Control) machine. The choice of these engines occurred due to the precision in the movements that can be obtained with these types of motors. The ultrasound probe serves to help, through the images acquired during the longitudinal movement, to monitor the application of the seeds. The parts that make up the system infrastructure were made of aluminum and translucent acrylic and cylindrical aluminum bars of different diameters. All these pieces were fixed and adjusted trough screws, washers, nuts and adhesive to metal, composing the final prototype of the PSIS. The project was developed and the PSIS prototype was assembled. The prototype presented acceptable operating characteristics for prostate implants. The advantage of this system is the automation of the application that provides an accurate positioning and movement of both probe and seed application. In addition to this study, seeds implantation tests will be performed, and

  3. Aspects of an automatic system of implants of radioactive seeds and anatomic object simulator for tests in prostate brachytherapy

    International Nuclear Information System (INIS)

    Silva, Leonardo S.M.; Braga, Viviane V.B.; Campos, Tarcísio P. R. de

    2017-01-01

    This work presents the state of the art of the research and development of an automatic radioactive seed implantation system (PSIS). PSIS may assist in the procedure of testing permanent implants in the prostate. These tests will be important in measurements of absorbed doses in the pelvic structures, involving the organs and tissues at risk to improve planning, seed positioning and dosimetry. The automated Prostate Seed Implant System (PSIS) has been designed to meet operational needs, which offers the freedom of positioning of the brachytherapy needle within the treatment area and ensures repeatability and fidelity to the planned treatment. Both the ultrasound probe and the seed implant needle are driven by step motors, Atmega microcontroller, bearings, aluminum shafts and a GUI (Graphical User Interface). Movement of both the probe and the needle holder was performed by fixed spindle on a threaded rod rushing to the step motors by a coupling. The step motors used to move the system consist of step motors used in CNC (Computer Numeric Control) machine. The choice of these engines occurred due to the precision in the movements that can be obtained with these types of motors. The ultrasound probe serves to help, through the images acquired during the longitudinal movement, to monitor the application of the seeds. The parts that make up the system infrastructure were made of aluminum and translucent acrylic and cylindrical aluminum bars of different diameters. All these pieces were fixed and adjusted trough screws, washers, nuts and adhesive to metal, composing the final prototype of the PSIS. The project was developed and the PSIS prototype was assembled. The prototype presented acceptable operating characteristics for prostate implants. The advantage of this system is the automation of the application that provides an accurate positioning and movement of both probe and seed application. In addition to this study, seeds implantation tests will be performed, and

  4. System overview of the fully implantable destination therapy--ReinHeart-total artificial heart.

    Science.gov (United States)

    Pelletier, Benedikt; Spiliopoulos, Sotirios; Finocchiaro, Thomas; Graef, Felix; Kuipers, Kristin; Laumen, Marco; Guersoy, Dilek; Steinseifer, Ulrich; Koerfer, Reiner; Tenderich, Gero

    2015-01-01

    Owing to the lack of suitable allografts, the demand for long-term mechanical circulatory support in patients with biventricular end-stage heart failure is rising. Currently available Total Artificial Heart (TAH) systems consist of pump units with only limited durability, percutaneous tubes and bulky external equipment that limit the quality of life. Therefore we are focusing on the development of a fully implantable, highly durable destination therapy total artificial heart. The ReinHeart-TAH system consists of a passively filling pump unit driven by a low-wear linear drive between two artificial ventricles, an implantable control unit and a compliance chamber. The TAH is powered by a transcutaneous energy transmission system. The flow distribution inside the ventricles was analysed by fluid structure interaction simulation and particle image velocimetry measurements. Along with durability tests, the hydrodynamic performance and flow balance capability were evaluated in a mock circulation loop. Animal trials are ongoing. Based on fluid structure interaction simulation and particle image velocimetry, blood stagnation areas have been significantly reduced. In the mock circulation loop the ReinHeart-TAH generated a cardiac output of 5 l/min at an operating frequency of 120 bpm and an aortic pressure of 120/80 mmHg. The highly effective preload sensitivity of the passively filling ventricles allowed the sensorless integration of the Frank Starling mechanism. The ReinHeart-TAH effectively replaced the native heart's function in animals for up to 2 days. In vitro and in vivo testing showed a safe and effective function of the ReinHeart-TAH system. This has the potential to become an alternative to transplantation. However, before a first-in-man implant, chronic animal trials still have to be completed. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  5. Ion implantation

    International Nuclear Information System (INIS)

    Dearnaley, Geoffrey

    1975-01-01

    First, ion implantation in semiconductors is discussed: ion penetration, annealing of damage, gettering, ion implanted semiconductor devices, equipement requirements for ion implantation. The importance of channeling for ion implantation is studied. Then, some applications of ion implantation in metals are presented: study of the corrosion of metals and alloys; influence or ion implantation on the surface-friction and wear properties of metals; hyperfine interactions in implanted metals

  6. Wireless microsensor network solutions for neurological implantable devices

    Science.gov (United States)

    Abraham, Jose K.; Whitchurch, Ashwin; Varadan, Vijay K.

    2005-05-01

    The design and development of wireless mocrosensor network systems for the treatment of many degenerative as well as traumatic neurological disorders is presented in this paper. Due to the advances in micro and nano sensors and wireless systems, the biomedical sensors have the potential to revolutionize many areas in healthcare systems. The integration of nanodevices with neurons that are in communication with smart microsensor systems has great potential in the treatment of many neurodegenerative brain disorders. It is well established that patients suffering from either Parkinson"s disease (PD) or Epilepsy have benefited from the advantages of implantable devices in the neural pathways of the brain to alter the undesired signals thus restoring proper function. In addition, implantable devices have successfully blocked pain signals and controlled various pelvic muscles in patients with urinary and fecal incontinence. Even though the existing technology has made a tremendous impact on controlling the deleterious effects of disease, it is still in its infancy. This paper presents solutions of many problems of today's implantable and neural-electronic interface devices by combining nanowires and microelectronics with BioMEMS and applying them at cellular level for the development of a total wireless feedback control system. The only device that will actually be implanted in this research is the electrodes. All necessary controllers will be housed in accessories that are outside the body that communicate with the implanted electrodes through tiny inductively-coupled antennas. A Parkinson disease patient can just wear a hat-system close to the implantable neural probe so that the patient is free to move around, while the sensors continually monitor, record, transmit all vital information to health care specialist. In the event of a problem, the system provides an early warning to the patient while they are still mobile thus providing them the opportunity to react and

  7. Fatigue induced changes in conical implant-abutment connections.

    Science.gov (United States)

    Blum, Kai; Wiest, Wolfram; Fella, Christian; Balles, Andreas; Dittmann, Jonas; Rack, Alexander; Maier, Dominik; Thomann, Ralf; Spies, Benedikt Christopher; Kohal, Ralf Joachim; Zabler, Simon; Nelson, Katja

    2015-11-01

    Based on the current lack of data and understanding of the wear behavior of dental two-piece implants, this study aims for evaluating the microgap formation and wear pattern of different implants in the course of cyclic loading. Several implant systems with different conical implant-abutment interfaces were purchased. The implants were first evaluated using synchrotron X-ray high-resolution radiography (SRX) and scanning electron microscopy (SEM). The implant-abutment assemblies were then subjected to cyclic loading at 98N and their microgap was evaluated after 100,000, 200,000 and 1 million cycles using SRX, synchrotron micro-tomography (μCT). Wear mechanisms of the implant-abutment connection (IAC) after 200,000 cycles and 1 million cycles were further characterized using SEM. All implants exhibit a microgap between the implant and abutment prior to loading. The gap size increased with cyclic loading with its changes being significantly higher within the first 200,000 cycles. Wear was seen in all implants regardless of their interface design. The wear pattern comprised adhesive wear and fretting. Wear behavior changed when a different mounting medium was used (brass vs. polymer). A micromotion of the abutment during cyclic loading can induce wear and wear particles in conical dental implant systems. This feature accompanied with the formation of a microgap at the IAC is highly relevant for the longevity of the implants. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  8. Wear at the Implant-Abutment Interface of Zirconia Abutments Manufactured by Three CAD/CAM Systems.

    Science.gov (United States)

    Pinheiro Tannure, Ana Luiza; Cunha, Alfredo Gonçalves; Borges Junior, Luiz Antônio; da Silva Concílio, Laís Regiane; Claro Neves, Ana Christina

    To evaluate the changes in the external-hexagon surface of the titanium (Ti) implant before and after mechanical cycling, when coupled with zirconia (Zr) abutments (A) manufactured by three computer-aided design/computer-aided manufacturing (CAD/CAM) systems (Neodent Digital, Zirkonzahn, and AmannGirrbach) and the ZrTi abutment manufactured by Neodent. Four groups were formed (n = 6): titanium implant with Zr AmannGirrbach abutment (AZrAG), with Zr Zirkonzahn abutment (AZrZ), with Zr Neodent abutment (AZrN), and with Zr abutment with infrastructure in Ti Neodent (AZrTiN). Standardized abutments were made from three identical abutments milled in wax. Images of the surface of each side of the hexagons of the implant were obtained by scanning electron microscopy, before and after mechanical cycling, to evaluate the parameters: (1) scratches in the hexagon face; (2) hexagon superior shoulder kneading; (3) hexagon shoulder wear; (4) alterations on the hexagon base; and (5) scratches on the hexagon top. The abutments were coupled with the implants, and Cr-Co crowns were cemented. The implant/abutment/crown assemblies were submitted to mechanical cycling (400 N, 8.0 Hz) for 1 million cycles. The observed changes were classified as follows: absence (0), mild (1), moderate (2), and severe (3). The results were analyzed using the Mann-Whitney, Kruskal-Wallis, and Dunn tests (P abutments, the AZrN group had shown more surface alterations. Among the Zr groups, AZrZ samples had shown the most altered surfaces, suggesting that alterations on the implant/Zr abutment hexagon surfaces are related to the abutment milled hexagon shape.

  9. Columnar transmitter based wireless power delivery system for implantable device in freely moving animals.

    Science.gov (United States)

    Eom, Kyungsik; Jeong, Joonsoo; Lee, Tae Hyung; Lee, Sung Eun; Jun, Sang Bum; Kim, Sung June

    2013-01-01

    A wireless power delivery system is developed to deliver electrical power to the neuroprosthetic devices that are implanted into animals freely moving inside the cage. The wireless powering cage is designed for long-term animal experiments without cumbersome wires for power supply or the replacement of batteries. In the present study, we propose a novel wireless power transmission system using resonator-based inductive links to increase power efficiency and to minimize the efficiency variations. A columnar transmitter coil is proposed to provide lateral uniformity of power efficiency. Using this columnar transmitter coil, only 7.2% efficiency fluctuation occurs from the maximum transmission efficiency of 25.9%. A flexible polymer-based planar type receiver coil is fabricated and assembled with a neural stimulator and an electrode. Using the designed columnar transmitter coil, the implantable device successfully operates while it moves freely inside the cage.

  10. A Wireless Magnetic Resonance Energy Transfer System for Micro Implantable Medical Sensors

    Directory of Open Access Journals (Sweden)

    Tianyang Yang

    2012-07-01

    Full Text Available Based on the magnetic resonance coupling principle, in this paper a wireless energy transfer system is designed and implemented for the power supply of micro-implantable medical sensors. The entire system is composed of the in vitro part, including the energy transmitting circuit and resonant transmitter coils, and in vivo part, including the micro resonant receiver coils and signal shaping chip which includes the rectifier module and LDO voltage regulator module. Transmitter and receiver coils are wound by Litz wire, and the diameter of the receiver coils is just 1.9 cm. The energy transfer efficiency of the four-coil system is greatly improved compared to the conventional two-coil system. When the distance between the transmitter coils and the receiver coils is 1.5 cm, the transfer efficiency is 85% at the frequency of 742 kHz. The power transfer efficiency can be optimized by adding magnetic enhanced resonators. The receiving voltage signal is converted to a stable output voltage of 3.3 V and a current of 10 mA at the distance of 2 cm. In addition, the output current varies with changes in the distance. The whole implanted part is packaged with PDMS of excellent biocompatibility and the volume of it is about 1 cm3.

  11. Evaluation of stabilization techniques for ion implant processing

    Science.gov (United States)

    Ross, Matthew F.; Wong, Selmer S.; Minter, Jason P.; Marlowe, Trey; Narcy, Mark E.; Livesay, William R.

    1999-06-01

    With the integration of high current ion implant processing into volume CMOS manufacturing, the need for photoresist stabilization to achieve a stable ion implant process is critical. This study compares electron beam stabilization, a non-thermal process, with more traditional thermal stabilization techniques such as hot plate baking and vacuum oven processing. The electron beam processing is carried out in a flood exposure system with no active heating of the wafer. These stabilization techniques are applied to typical ion implant processes that might be found in a CMOS production process flow. The stabilization processes are applied to a 1.1 micrometers thick PFI-38A i-line photoresist film prior to ion implant processing. Post stabilization CD variation is detailed with respect to wall slope and feature integrity. SEM photographs detail the effects of the stabilization technique on photoresist features. The thermal stability of the photoresist is shown for different levels of stabilization and post stabilization thermal cycling. Thermal flow stability of the photoresist is detailed via SEM photographs. A significant improvement in thermal stability is achieved with the electron beam process, such that photoresist features are stable to temperatures in excess of 200 degrees C. Ion implant processing parameters are evaluated and compared for the different stabilization methods. Ion implant system end-station chamber pressure is detailed as a function of ion implant process and stabilization condition. The ion implant process conditions are detailed for varying factors such as ion current, energy, and total dose. A reduction in the ion implant systems end-station chamber pressure is achieved with the electron beam stabilization process over the other techniques considered. This reduction in end-station chamber pressure is shown to provide a reduction in total process time for a given ion implant dose. Improvements in the ion implant process are detailed across

  12. Immediate and early function of Brånemark System implants placed in the esthetic zone: a 1-year prospective clinical multicenter study.

    Science.gov (United States)

    Maló, Paulo; Friberg, Bertil; Polizzi, Giovanni; Gualini, Federico; Vighagen, Torbjörn; Rangert, Bo

    2003-01-01

    Immediate/early implant function means great benefits for patients and therapists because treatment time and cost can be substantially reduced. This concept has become an accepted alternative for complete arch fixed restorations in the mandible, and clinical documentation is emerging for other indications. The purpose of this prospective clinical multicenter study was to evaluate the outcome of implants placed in incisor, canine, and premolar regions in maxillas or mandibles. Implants were loaded with provisional crowns and bridges on the same day or within a few days and were followed up for 1 year during function. Four centers treated 76 patients each in need of an implant-retained prosthesis in the anterior and premolar regions in the maxilla or mandible. A total of 116 titanium implants with machined surfaces (Brånemark System , Nobel Biocare AB, Gothenburg, Sweden) were placed: 74 in maxillas and 42 in mandibles. Eighty-seven prostheses were made, of which 63 were single crowns and 24 were bridges (supported by 53 splinted implants). Twenty-two implants in 14 patients were placed in fresh extraction sites. The goal with the preparation and insertion technique was to achieve good primary implant stability and a minimum implant insertion torque of 30 Ncm before the implant was completely seated. The occlusion was adjusted to eliminate direct contact with the provisional prostheses. After 6 months, the patients received their permanent prostheses. Sixty-seven patients were followed for 1 year. Five implants were lost in five patients, three in the maxilla and two in the mandible. Four of the lost implants were single-tooth replacements and one was splinted. The cumulative survival rate (CSR) was 95.7% for all implants after 1 year and 93.7% and 98.1% for single-tooth and splinted implants, respectively. There were no implant losses in the extraction sites. The CSR of 96% at 1 year indicates that immediate function of Brånemark System implants placed in incisor

  13. Evaluation of an infrared camera and X-ray system using implanted fiducials in patients with lung tumors for gated radiation therapy

    International Nuclear Information System (INIS)

    Willoughby, Twyla R.; Forbes, Alan R.; Buchholz, Daniel; Langen, Katja M.; Wagner, Thomas H.; Zeidan, Omar A.; Kupelian, Patrick A.; Meeks, Sanford L.

    2006-01-01

    Purpose: To report on the initial clinical use of a commercially available system to deliver gated treatment using implanted fiducials, in-room kV X-rays, and an infrared camera tracking system. Methods and Materials: ExacTrac Adaptive Gating from BrainLab is a localization system using infrared cameras and X-rays. Gating signals are the patient's breathing pattern obtained from infrared reflectors on the patient. kV X-rays of an implanted fiducial are synchronized to the breathing pattern. After localization and shift of the patient to isocenter, the breathing pattern is used to gate Radiation. Feasibility tests included localization accuracy, radiation output constancy, and dose distributions with gating. Clinical experience is reported on treatment of patients with small lung lesions. Results: Localization accuracy of a moving target with gating was 1.7 mm. Dose constancy measurements showed insignificant change in output with gating. Improvements of dose distributions on moving targets improved with gating. Eleven patients with lung lesions were implanted with 20 mm x 0.7 mm gold coil (Visicoil). The implanted fiducial was used to localize and treat the patients with gating. Treatment planning and repeat computed tomographic scans showed that the change in center of gross target volume (GTV) to implanted marker averaged 2.47 mm due in part to asymmetric tumor shrinkage. Conclusion: ExacTrac Adaptive Gating has been used to treat lung lesions. Initial system evaluation verified its accuracy and usability. Implanted fiducials are visible in X-rays and did not migrate

  14. Elders with implant overdentures: a 22-year clinical report.

    Science.gov (United States)

    Alsabeeha, Nabeel H M

    2012-09-01

    To report on the long-term survival and prosthodontic maintenance of two edentulous adults with mandibular overdentures supported by hydroxyapatite (HA)-coated implants. Mandibular implant overdentures are a successful treatment option with positive impact on the quality of life of elderly edentulous adults. Long-term survival of the implants requires continued rigorous prosthodontic maintenance. Two elderly edentulous adults with mandibular overdentures supported by 2 HA-coated implants were presented for prosthodontic rehabilitation after 22 years of placement. The implants were osseo-integrated and surviving at presentation based on accepted criteria. The mandibular implant overdentures suffered recurrent loss of retention and stability. Prosthodontic treatment involving the replacement of defective attachment systems and construction of new sets of mandibular implant overdentures opposing complete maxillary dentures is presented. The long-term survival of mandibular 2-implant overdentures requires continued prosthodontic maintenance. A conservative approach in the rehabilitation of two older edentulous adults with mandibular 2-implant overdentures was described including proper selection of attachment systems. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

  15. Cochlear implantation in children and adults in Switzerland.

    Science.gov (United States)

    Brand, Yves; Senn, Pascal; Kompis, Martin; Dillier, Norbert; Allum, John H J

    2014-02-04

    The cochlear implant (CI) is one of the most successful neural prostheses developed to date. It offers artificial hearing to individuals with profound sensorineural hearing loss and with insufficient benefit from conventional hearing aids. The first implants available some 30 years ago provided a limited sensation of sound. The benefit for users of these early systems was mostly a facilitation of lip-reading based communication rather than an understanding of speech. Considerable progress has been made since then. Modern, multichannel implant systems feature complex speech processing strategies, high stimulation rates and multiple sites of stimulation in the cochlea. Equipped with such a state-of-the-art system, the majority of recipients today can communicate orally without visual cues and can even use the telephone. The impact of CIs on deaf individuals and on the deaf community has thus been exceptional. To date, more than 300,000 patients worldwide have received CIs. In Switzerland, the first implantation was performed in 1977 and, as of 2012, over 2,000 systems have been implanted with a current rate of around 150 CIs per year. The primary purpose of this article is to provide a contemporary overview of cochlear implantation, emphasising the situation in Switzerland.

  16. Finite element analysis of the stress distributions in peri-implant bone in modified and standard-threaded dental implants

    Directory of Open Access Journals (Sweden)

    Serkan Dundar

    2016-01-01

    Full Text Available The aim of this study was to examine the stress distributions with three different loads in two different geometric and threaded types of dental implants by finite element analysis. For this purpose, two different implant models, Nobel Replace and Nobel Active (Nobel Biocare, Zurich, Switzerland, which are currently used in clinical cases, were constructed by using ANSYS Workbench 12.1. The stress distributions on components of the implant system under three different static loadings were analysed for the two models. The maximum stress values that occurred in all components were observed in FIII (300 N. The maximum stress values occurred in FIII (300 N when the Nobel Replace implant is used, whereas the lowest ones, in the case of FI (150 N loading in the Nobel Active implant. In all models, the maximum tensions were observed to be in the neck region of the implants. Increasing the connection between the implant and the bone surface may allow more uniform distribution of the forces of the dental implant and may protect the bone around the implant. Thus, the implant could remain in the mouth for longer periods. Variable-thread tapered implants can increase the implant and bone contact.

  17. Predicting the Failure of Dental Implants Using Supervised Learning Techniques

    Directory of Open Access Journals (Sweden)

    Chia-Hui Liu

    2018-05-01

    Full Text Available Prosthodontic treatment has been a crucial part of dental treatment for patients with full mouth rehabilitation. Dental implant surgeries that replace conventional dentures using titanium fixtures have become the top choice. However, because of the wide-ranging scope of implant surgeries, patients’ body conditions, surgeons’ experience, and the choice of implant system should be considered during treatment. The higher price charged by dental implant treatments compared to conventional dentures has led to a rush among medical staff; therefore, the future impact of surgeries has not been analyzed in detail, resulting in medial disputes. Previous literature on the success factors of dental implants is mainly focused on single factors such as patients’ systemic diseases, operation methods, or prosthesis types for statistical correlation significance analysis. This study developed a prediction model for providing an early warning mechanism to reduce the chances of dental implant failure. We collected the clinical data of patients who received artificial dental implants at the case hospital for a total of 8 categories and 20 variables. Supervised learning techniques such as decision tree (DT, support vector machines, logistic regressions, and classifier ensembles (i.e., Bagging and AdaBoost were used to analyze the prediction of the failure of dental implants. The results show that DT with both Bagging and Adaboost techniques possesses the highest prediction performance for the failure of dental implant (area under the receiver operating characteristic curve, AUC: 0.741; the analysis also revealed that the implant systems affect dental implant failure. The model can help clinical surgeons to reduce medical failures by choosing the optimal implant system and prosthodontics treatments for their patients.

  18. MRI information for commonly used otologic implants: review and update.

    Science.gov (United States)

    Azadarmaki, Roya; Tubbs, Rhonda; Chen, Douglas A; Shellock, Frank G

    2014-04-01

    To review information on magnetic resonance imaging (MRI) issues for commonly used otologic implants. Manufacturing companies, National Library of Medicine's online database, and an additional online database (www.MRIsafety.com). A literature review of the National Library of Medicine's online database with focus on MRI issues for otologic implants was performed. The MRI information on implants provided by manufacturers was reviewed. Baha and Ponto Pro osseointegrated implants' abutment and fixture and the implanted magnet of the Sophono Alpha 1 and 2 abutment-free systems are approved for 3-Tesla magnetic resonance (MR) systems. The external processors of these devices are MR Unsafe. Of the implants tested, middle ear ossicular prostheses, including stapes prostheses, except for the 1987 McGee prosthesis, are MR Conditional for 1.5-Tesla (and many are approved for 3-Tesla) MR systems. Cochlear implants with removable magnets are approved for patients undergoing MRI at 1.5 Tesla after magnet removal. The MED-EL PULSAR, SONATA, CONCERT, and CONCERT PIN cochlear implants can be used in patients undergoing MRI at 1.5 Tesla with application of a protective bandage. The MED-EL COMBI 40+ can be used in 0.2-Tesla MR systems. Implants made from nonmagnetic and nonconducting materials are MR Safe. Knowledge of MRI guidelines for commonly used otologic implants is important. Guidelines on MRI issues approved by the US Food and Drug Administration are not always the same compared with other parts of the world. This monograph provides a current reference for physicians on MRI issues for commonly used otologic implants.

  19. Air Abrasive Disinfection of Implant Surfaces in a Simulated Model of Peri-Implantitis

    Science.gov (United States)

    2016-06-01

    may be higher in patients diagnosed with periodontal disease, systemic chronic disease such as diabetes or patients who smoke tobacco.9,10 One of...flora associated with peri-implantitis is similar to that found in chronic periodontitis .14 Gram-positive, facultative bacteria are normally...9):1490-5. 20. Heitz-Mayfield LJ, Lang NP. Comparative biology of chronic and aggressive periodontitis vs. peri-implantitis. Periodontol 2000

  20. Implantable enzyme amperometric biosensors.

    Science.gov (United States)

    Kotanen, Christian N; Moussy, Francis Gabriel; Carrara, Sandro; Guiseppi-Elie, Anthony

    2012-05-15

    The implantable enzyme amperometric biosensor continues as the dominant in vivo format for the detection, monitoring and reporting of biochemical analytes related to a wide range of pathologies. Widely used in animal studies, there is increasing emphasis on their use in diabetes care and management, the management of trauma-associated hemorrhage and in critical care monitoring by intensivists in the ICU. These frontier opportunities demand continuous indwelling performance for up to several years, well in excess of the currently approved seven days. This review outlines the many challenges to successful deployment of chronically implantable amperometric enzyme biosensors and emphasizes the emerging technological approaches in their continued development. The foreign body response plays a prominent role in implantable biotransducer failure. Topics considering the approaches to mitigate the inflammatory response, use of biomimetic chemistries, nanostructured topographies, drug eluting constructs, and tissue-to-device interface modulus matching are reviewed. Similarly, factors that influence biotransducer performance such as enzyme stability, substrate interference, mediator selection and calibration are reviewed. For the biosensor system, the opportunities and challenges of integration, guided by footprint requirements, the limitations of mixed signal electronics, and power requirements, has produced three systems approaches. The potential is great. However, integration along the multiple length scales needed to address fundamental issues and integration across the diverse disciplines needed to achieve success of these highly integrated systems, continues to be a challenge in the development and deployment of implantable amperometric enzyme biosensor systems. Copyright © 2012 Elsevier B.V. All rights reserved.

  1. Technical feasibility of the implantation of a monorail stent system into the renal arteries without pre-dilatation

    International Nuclear Information System (INIS)

    Neumann, C.; Dorffner, R.; Gschwendtner, M.; Karnel, F.; Mair, J.; Dorffner, G.

    2005-01-01

    Purpose: to evaluate the technical feasibility of the implantation of the monorail RX Herculink trademark system into the renal arteries without pre-dilatation. Materials and methods: forty-two patients (mean age 71 years) from four centers with a total of 44 renal artery stenoses underwent implantation of the RX Herculink trademark stent. The mean grade of the stenosis was 83.8%, the mean length 7.5 mm. The stenoses were ostial in 38 cases and in immediate proximity to the ostium in 6 cases. The mean follow-up-period was 57 weeks (24 - 176 weeks). Results: in 42 cases, the implantation was successful without pre-dilatation. In 2 cases, pre-dilatation was carried out. In none of the cases, detachment of the stent from the balloon was observed. In one stenosis with a length of 17 mm, implantation of two stents was performed. In 9 cases, post-dilatation with a larger balloon or higher balloon pressure was necessary. Residual stenoses exceeding 30% were not observed. Two patients developed local bleeding at the puncture site. During the follow-up, restenoses were observed in 5 stents after 26 to 126 weeks, which necessitated a second intervention in 3 cases (PTA in 2 cases, re-stenting in 1 case). The primary patency rate after 6 and 12 months was 0.92 ± 0.056 according to Kaplan-Meier, the secondary patency rate after 6 and 12 months was 1.0 ± 0.0. Conclusion: implantation of the RX Herculink trademark stent system into the renal arteries without pre-dilatation is technically feasible and safe. Even without pre-dilatation, the stent-system can be advanced through the stenosis without detachment. The complication rate is low. Our clinical results are comparable to previous studies. (orig.)

  2. Implantation activation annealing of Si-implanted gallium nitride at temperatures > 1,100 C

    International Nuclear Information System (INIS)

    Zolper, J.C.; Han, J.; Biefeld, R.M.

    1997-01-01

    The activation annealing of Si-implanted GaN is reported for temperatures from 1,100 to 1,400 C. Although previous work has shown that Si-implanted GaN can be activated by a rapid thermal annealing at ∼1,100 C, it was also shown that significant damage remained in the crystal. Therefore, both AlN-encapsulated and uncapped Si-implanted GaN samples were annealed in a metal organic chemical vapor deposition system in a N 2 /NH 3 ambient to further assess the annealing process. Electrical Hall characterization shows increases in carrier density and mobility for annealing up to 1,300 C before degrading at 1,400 C due to decomposition of the GaN epilayer. Rutherford backscattering spectra show that the high annealing temperatures reduce the implantation induced damage profile but do not completely restore the as-grown crystallinity

  3. [Total cervical disk replacement--implant-specific approaches: keel implant (Prodisc-C intervertebral disk prosthesis)].

    Science.gov (United States)

    Korge, Andreas; Siepe, Christoph J; Heider, Franziska; Mayer, H Michael

    2010-11-01

    Dynamic intervertebral support of the cervical spine via an anterolateral approach using a modular artificial disk prosthesis with end-plate fixation by central keel fixation. Cervical median or mediolateral disk herniations, symptomatic cervical disk disease (SCDD) with anterior osseous, ligamentous and/or discogenic narrowing of the spinal canal. Cervical fractures, tumors, osteoporosis, arthrogenic neck pain, severe facet degeneration, increased segmental instability, ossification of posterior longitudinal ligament (OPLL), severe osteopenia, acute and chronic systemic, spinal or local infections, systemic and metabolic diseases, known implant allergy, pregnancy, severe adiposity (body mass index > 36 kg/m2), reduced patient compliance, alcohol abuse, drug abuse and dependency. Exposure of the anterior cervical spine using the minimally invasive anterolateral approach. Intervertebral fixation of retainer screws. Intervertebral diskectomy. Segmental distraction with vertebral body retainer and vertebral distractor. Removal of end-plate cartilage. Microscopically assisted decompression of spinal canal. Insertion of trial implant to determine appropriate implant size, height and position. After biplanar image intensifier control, drilling for keel preparation using drill guide and drill bit, keel-cut cleaner to remove bone material from the keel cut, radiologic control of depth of the keel cut using the corresponding position gauge. Implantation of original implant under lateral image intensifier control. Removal of implant inserter. Functional postoperative care and mobilization without external support, brace not used routinely, soft brace possible for 14 days due to postoperative pain syndromes. Implantation of 100 cervical Prodisc-C disk prostheses in 78 patients (average age 48 years) at a single center. Clinical and radiologic follow-up 24 months postoperatively. Significant improvement based on visual analog scale and Neck Disability Index. Radiologic

  4. PAIN RELIEF MEDIATED BY IMPLANTABLE DRUG-DELIVERY DEVICES

    NARCIS (Netherlands)

    HOEKSTRA, A

    Various totally implantable drug delivery systems from single access ports to micropumps are now available for administration of repeated boluses, and continuous or programmable infusions. In this respect, emphasis is given to a relatively cheap, totally implantable system for self-administering

  5. Chewing efficiency and maximum bite force with different attachment systems of implant overdentures: a crossover study.

    Science.gov (United States)

    Elsyad, Moustafa Abdou; Khairallah, Ahmed Samir

    2017-06-01

    This crossover study aimed to evaluate and compare chewing efficiency and maximum bite force (MBF) with resilient telescopic and bar attachment systems of implant overdentures in patients with atrophied mandibles. Ten participants with severely resorbed mandibles and persistent denture problems received new maxillary and mandibular conventional dentures (control, CD). After 3 months of adaptation, two implants were inserted in canine region of the mandible. In a quasi-random method, overdentures were connected to the implants with either bar overdentures (BOD) or resilient telescopic overdentures (TOD) attachment systems. Chewing efficiency in terms of unmixed fraction (UF) was measured using chewing gum (after 5, 10, 20, 30 and 50 strokes), and MBF was measured using a bite force transducer. Measurements were performed 3 months after using each of the following prostheses: CD, BOD and TOD. Chewing efficiency and MBF increased significantly with BOD and TOD compared to CD. As the number of chewing cycles increased, the UF decreased. TOD recorded significant higher chewing efficiency and MBF than BOD. Resilient telescopic attachments are associated with increased chewing efficiency and MBF compared bar attachments when used to retain overdentures to the implants in patients with atrophied mandibles. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. The impact of glucocorticosteroids administered for systemic diseases on the osseointegration and survival of dental implants placed without bone grafting-A retrospective study in 31 patients.

    Science.gov (United States)

    Petsinis, Vassilis; Kamperos, Georgios; Alexandridi, Foteini; Alexandridis, Konstantinos

    2017-08-01

    To evaluate the impact of glucocorticosteroids, administered for the treatment of systemic diseases, on the osseointegration and survival of dental implants placed without bone grafting. A retrospective study was conducted in search of patients treated with dental implants while receiving glucocorticosteroid therapy for various systemic diseases. In these cases, a conventional two-stage surgical protocol was used, without bone regeneration procedures. The osseointegration was clinically and radiographically tested at the uncovering of the implants. The follow-up after loading was set at a minimum of 3 years. A total of 31 patients were included in the study. Of the 105 dental implants placed, 104 were osseointegrated (99%). No bone absorption was radiographically noted at the uncovering of the osseointegrated implants. All of the osseointegrated implants were successfully loaded for the prosthetic restoration. The mean follow-up period after loading was 71 months, with an implant survival rate of 99%. Glucocorticosteroid intake for systemic diseases does not have a significant impact on the osseointegration and the 3-year survival of dental implants placed with a conventional two-stage surgical protocol and without bone grafting. Therefore, it should not be considered a contraindication for dental implant placement. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. Published by Elsevier Ltd. All rights reserved.

  7. Bone anchors or interference screws? A biomechanical evaluation for autograft ankle stabilization.

    Science.gov (United States)

    Jeys, Lee; Korrosis, Sotiris; Stewart, Todd; Harris, Nicholas J

    2004-01-01

    Autograft stabilization uses free semitendinosus tendon grafts to anatomically reconstruct the anterior talofibular ligament. Study aims were to evaluate the biomechanical properties of Mitek GII anchors compared with the Arthrex Bio-Tenodesis Screw for free tendon reconstruction of the anterior talofibular ligament. There are no differences in load to failure and percentage specimen elongation at failure between the 2 methods. Controlled laboratory study using porcine models. Sixty porcine tendon constructs were failure tested. Re-creating the pull of the anterior talofibular ligament, loads were applied at 70 degrees to the bones. Thirty-six tendons were fixed to porcine tali and tested using a single pull to failure; 10 were secured with anchors and No. 2 Ethibond, 10 with anchors and FiberWire, 10 with screws and Fiberwire, and 6 with partially gripped screws. Cyclic preloading was conducted on 6 tendons fixed by anchors and on 6 tendons fixed by screws before failure testing. Two groups of 6 components fixed to the fibula were also tested. The talus single-pull anchor group produced a mean load of 114 N and elongation of 37% at failure. The talus single-pull screw group produced a mean load of 227 N and elongation of 22% at failure (P anchors. The improved biomechanics of interference screws suggests that these may be more suited to in vivo reconstruction of the anterior talofibular ligament than are bone anchors.

  8. Persistent bone marrow edema after osteochondral autograft transplantation in the knee joint

    International Nuclear Information System (INIS)

    Nemec, Stefan Franz; Marlovits, Stefan; Trattnig, Siegfried

    2009-01-01

    Background and objective: The assessment of bone marrow edema-like signal intensity in magnetic resonance imaging (MRI) in patients after osteochondral autograft transplantation (OCT) in the knee joint is a parameter of yet indefinite value. This study determines the prevalence of persistent edema-like signal intensity in OCT patients and evaluates the correlation between edema and morphological imaging findings of the graft and clinical pain symptoms. Materials and methods: In this longitudinal observational study, 10 patients after OCT were followed by MRI prospectively 1 month, 3 months, 6 months, 12 months, and 24 months post-operatively. All MR examinations were performed on a 1.0 T MR unit with the same protocol using a modified scoring system (magnetic resonance observation of cartilage repair tissue-MOCART) for evaluation. Edema-like signal intensity in and beneath the osteochondral graft was assessed in its prevalence and graded using a coronal short tau inversion recovery fast spin echo (STIR-FSE) sequence: grade 1, normal; grade 2, moderate (diameter 2 cm). The finding of edema-like signal intensity was correlated with graded parameters describing the morphology of the repair tissue assessed in a sagittal dual FSE sequence including: (a) surface of repair tissue: grade 1, intact; grade 2, damaged. (b) Cartilage interface: grade 1, complete; grade 2, incomplete. (c) Bone interface: grade 1, complete; grade 2, delamination. The finding of edema-like signal intensity was also correlated with the KOOS pain score assessing knee pain after 12 months. Results: Initially, after 1 month the prevalence of edema-like signal intensity was 70% (7/10 patients) and finally after 24 months 60% (6/10 patients). We found no significant relationship between the prevalence and degree of edema-like signal intensity and parameters describing the morphology of the repair tissue. Also the clinical pain score did not show significant correlation with edema. Conclusion

  9. Short dental implants: an emerging concept in implant treatment.

    Science.gov (United States)

    Al-Hashedi, Ashwaq Ali; Taiyeb Ali, Tara Bai; Yunus, Norsiah

    2014-06-01

    Short implants have been advocated as a treatment option in many clinical situations where the use of conventional implants is limited. This review outlines the effectiveness and clinical outcomes of using short implants as a valid treatment option in the rehabilitation of edentulous atrophic alveolar ridges. Initially, an electronic search was performed on the following databases: Medline, PubMed, Embase, Cochrane Database of Systematic Reviews, and DARE using key words from January 1990 until May 2012. An additional hand search was included for the relevant articles in the following journals: International Journal of Oral and Maxillofacial Implants, Clinical Oral Implants Research, Journal of Clinical Periodontology, International Journal of Periodontics, Journal of Periodontology, and Clinical Implant Dentistry and Related Research. Any relevant papers from the journals' references were hand searched. Articles were included if they provided detailed data on implant length, reported survival rates, mentioned measures for implant failure, were in the English language, involved human subjects, and researched implants inserted in healed atrophic ridges with a follow-up period of at least 1 year after implant-prosthesis loading. Short implants demonstrated a high rate of success in the replacement of missing teeth in especially atrophic alveolar ridges. The advanced technology and improvement of the implant surfaces have encouraged the success of short implants to a comparable level to that of standard implants. However, further randomized controlled clinical trials and prospective studies with longer follow-up periods are needed.

  10. Digital photoelastic analysis applied to implant dentistry

    Science.gov (United States)

    Ramesh, K.; Hariprasad, M. P.; Bhuvanewari, S.

    2016-12-01

    Development of improved designs of implant systems in dentistry have necessitated the study of stress fields in the implant regions of the mandible/maxilla for better understanding of the biomechanics involved. Photoelasticity has been used for various studies related to dental implants in view of whole field visualization of maximum shear stress in the form of isochromatic contours. The potential of digital photoelasticity has not been fully exploited in the field of implant dentistry. In this paper, the fringe field in the vicinity of the connected implants (All-On-Four® concept) is analyzed using recent advances in digital photoelasticity. Initially, a novel 3-D photoelastic model making procedure, to closely mimic all the anatomical features of the human mandible is proposed. By choosing appropriate orientation of the model with respect to the light path, the essential region of interest were sought to be analysed while keeping the model under live loading conditions. Need for a sophisticated software module to carefully identify the model domain has been brought out. For data extraction, five-step method is used and isochromatics are evaluated by twelve fringe photoelasticity. In addition to the isochromatic fringe field, whole field isoclinic data is also obtained for the first time in implant dentistry, which could throw important information in improving the structural stability of the implant systems. Analysis is carried out for the implant in the molar as well as the incisor region. In addition, the interaction effects of loaded molar implant on the incisor area are also studied.

  11. A direct plasma injection system into an RFQ for clean and safe ion implantation

    International Nuclear Information System (INIS)

    Takeuchi, T.; Katayama, T.; Okamura, M.; Yano, K.; Sakumi, A.; Hattori, T.; Hayashizaki, N.; Jameson, R.A.

    2002-01-01

    A new injection system, direct plasma injection system, was tested and its principle was proved successfully. We found that one of advantages of this injection system was efficient consumption of source materials. Large portions of induced ions can be injected into a first stage accelerator. This feature is quite useful for ion implantation applications, because toxic exhaust gas can be eliminated. In order to utilize this system for industrial application, the feasibility of a boron injection scheme using a Nd:YAG laser system was investigated

  12. Application of the cultured epidermal autograft "JACE(®") for treatment of severe burns: Results of a 6-year multicenter surveillance in Japan.

    Science.gov (United States)

    Matsumura, Hajime; Matsushima, Asako; Ueyama, Masashi; Kumagai, Norio

    2016-06-01

    In the 1970s, Green et al. developed a method that involved culturing keratinocyte sheets and used for treatment of burns. Since then, the take rate of cultured epidermal autograft (CEA) onto fascia, granulation tissue, or allografts has been extensively reported, while that on an artificial dermis in a large case series is not. Moreover, the contribution of CEA to patient survival has not been analyzed in a multicenter study. We conducted a 6-year multicenter surveillance on the application of the CEA "JACE(®") for treatment of burns >30% total body surface area (TBSA) across 118 Japanese hospitals. This surveillance included 216 patients and 718 graft sites for efficacy analysis. The CEA take rate at 4 weeks after grafting was evaluated, and safety was monitored until 52 weeks. In addition, the survival curve obtained in this study and the data obtained from the Tokyo Burn Unit Association (TBUA) were compared. The mean CEA take rates at week 4 were 66% (sites) and 68% (patients), and the rate on the artificial dermis was 65% for 226 sites. CEA application combined with wide split-thickness auto or patch autograft increased the CEA take rate. On comparison with the data obtained from the TBUA, which included data on individuals with burns of the same severity, CEA application was found to contribute to patient survival until 7 weeks after burn. We reported the take rate of CEA based on a 6-year multicenter surveillance. From our results, we found that the application of CEA is a useful treatment for the patients with extensive burns. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  13. Magnet-Retained Two-Mini-Implant Overdenture: Clinical and Mechanical Consideration

    Directory of Open Access Journals (Sweden)

    Yuichi Ishida

    2016-10-01

    Full Text Available Two-implant overdentures have become the accepted treatment for restoring mandibular edentulism. The dimensions of regular implants sometimes limit their use, such as in the case of narrow ridges. Mini-implants with reduced diameters (less than 3.0 mm enable insertion into narrow ridges. A magnet-retained two-mini-implant overdenture system was developed and is described in this paper. Additionally, we describe a clinical mandibular procedure using the system and evaluate its biomechanical performance.

  14. Number of implants for mandibular implant overdentures: a systematic review

    Science.gov (United States)

    Lee, Jeong-Yol; Kim, Ha-Young; Bryant, S. Ross

    2012-01-01

    PURPOSE The aim of this systematic review is to address treatment outcomes of Mandibular implant overdentures relative to implant survival rate, maintenance and complications, and patient satisfaction. MATERIALS AND METHODS A systematic literature search was conducted by a PubMed search strategy and hand-searching of relevant journals from included studies. Randomized Clinical Trials (RCT) and comparative clinical trial studies on mandibular implant overdentures until August, 2010 were selected. Eleven studies from 1098 studies were finally selected and data were analyzed relative to number of implants. RESULTS Six studies presented the data of the implant survival rate which ranged from 95% to 100% for 2 and 4 implant group and from 81.8% to 96.1% for 1 and 2 implant group. One study, which statistically compared implant survival rate showed no significant differences relative to the number of implants. The most common type of prosthetic maintenance and complications were replacement or reattaching of loose clips for 2 and 4 implant group, and denture repair due to the fracture around an implant for 1 and 2 implant groups. Most studies showed no significant differences in the rate of prosthetic maintenance and complication, and patient satisfaction regardless the number of implants. CONCLUSION The implant survival rate of mandibular overdentures is high regardless of the number of implants. Denture maintenance is likely not inflenced substantially by the number of implants and patient satisfaction is typically high again regardless os the number of implants. PMID:23236572

  15. Wireless Power Transfer Strategies for Implantable Bioelectronics.

    Science.gov (United States)

    Agarwal, Kush; Jegadeesan, Rangarajan; Guo, Yong-Xin; Thakor, Nitish V

    2017-01-01

    Neural implants have emerged over the last decade as highly effective solutions for the treatment of dysfunctions and disorders of the nervous system. These implants establish a direct, often bidirectional, interface to the nervous system, both sensing neural signals and providing therapeutic treatments. As a result of the technological progress and successful clinical demonstrations, completely implantable solutions have become a reality and are now commercially available for the treatment of various functional disorders. Central to this development is the wireless power transfer (WPT) that has enabled implantable medical devices (IMDs) to function for extended durations in mobile subjects. In this review, we present the theory, link design, and challenges, along with their probable solutions for the traditional near-field resonant inductively coupled WPT, capacitively coupled short-ranged WPT, and more recently developed ultrasonic, mid-field, and far-field coupled WPT technologies for implantable applications. A comparison of various power transfer methods based on their power budgets and WPT range follows. Power requirements of specific implants like cochlear, retinal, cortical, and peripheral are also considered and currently available IMD solutions are discussed. Patient's safety concerns with respect to electrical, biological, physical, electromagnetic interference, and cyber security from an implanted neurotech device are also explored in this review. Finally, we discuss and anticipate future developments that will enhance the capabilities of current-day wirelessly powered implants and make them more efficient and integrable with other electronic components in IMDs.

  16. A wireless transmission system powered by an enzyme biofuel cell implanted in an orange.

    Science.gov (United States)

    MacVittie, Kevin; Conlon, Tyler; Katz, Evgeny

    2015-12-01

    A biofuel cell composed of catalytic electrodes made of "buckypaper" modified with PQQ-dependent glucose dehydrogenase and FAD-dependent fructose dehydrogenase on the anode and with laccase on the cathode was used to activate a wireless information transmission system. The cathode/anode pair was implanted in orange pulp extracting power from its content (glucose and fructose in the juice). The open circuit voltage, Voc, short circuit current density, jsc, and maximum power produced by the biofuel cell, Pmax, were found as ca. 0.6 V, ca. 0.33 mA·cm(-2) and 670 μW, respectively. The voltage produced by the biofuel cell was amplified with an energy harvesting circuit and applied to a wireless transmitter. The present study continues the research line where different implantable biofuel cells are used for the activation of electronic devices. The study emphasizes the biosensor and environmental monitoring applications of implantable biofuel cells harvesting power from natural sources, rather than their biomedical use. Copyright © 2014 Elsevier B.V. All rights reserved.

  17. Low-Gain, Low-Noise Integrated Neuronal Amplifier for Implantable Artifact-Reduction Recording System

    OpenAIRE

    Zbrzeski, Adeline; Lewis, Noëlle; Rummens, Francois; Jung, Ranu; N'Kaoua, Gilles; Benazzouz, Abdelhamid; Renaud, Sylvie

    2013-01-01

    Brain neuroprostheses for neuromodulation are being designed to monitor the neural activity of the brain in the vicinity of the region being stimulated using a single macro-electrode. Using a single macro-electrode, recent neuromodulation studies show that recording systems with a low gain neuronal amplifier and successive amplifier stages can reduce or reject stimulation artifacts. These systems were made with off-the-shelf components that are not amendable for future implant design. A low-g...

  18. Autografting of peripheral-blood progenitor cells early in chronic myeloid Leukemia Transplante autólogo de células progenitoras em fase crônica precoce da Leucemia mielóide crônica

    Directory of Open Access Journals (Sweden)

    Paulo V. B. Carvalho

    2004-12-01

    Full Text Available The role of peripheral-blood progenitor cell (PBPC transplantation as a treatment for chronic myeloid leukemia (CML patients remains uncertain. We presented herein 11 CML patients treated with autografting of PBPC in early chronic phase followed by interferon-alpha (IFN-alpha. Bone marrow samples obtained at diagnosis and during follow-up after autografting as well as leukapheresis products were analyzed by cytogenetics, fluorescence in situ hybridization (FISH and reverse transcriptase-polymerase chain reaction (RT-PCR. The median follow-up of patients after autografting was 22 months (range: 1-49. Two treatment-related deaths occurred in patients enrolled in the study. Eight out of 9 (88.9% and 7 out of 9 (77.8% patients achieved hematologic and cytogenetic responses, respectively. Molecular cytogenetic and molecular responses were seen in all 7 patients analyzed (100.0% and in one single patient (11.1%, respectively. The median percentages of Ph+ (78.0% metaphases obtained after 6 months of autografting was lower than those obtained at diagnosis (100.0%, P=0.04. The median percentages of FISH+ nuclei obtained at 3 (4.0%, 6 (7.3% and 9 (14.7% months after autografting were also lower than that obtained at diagnosis (82.5%; P=0.002; P=0.003; P=0.030, respectively. At the end of the study, 9 patients (81.8% were alive in chronic phase, 4 of them presenting hematologic, cytogenetic and molecular cytogenetic responses. We conclude that autografting performed with PBPC in early chronic phase of CML followed by IFN-alpha results in lower numbers of Ph+ and FISH+ cells in bone marrow.O papel do transplante de célula progenitora periférica (CPP como tratamento de pacientes com leucemia mielóide crônica (LMC permanece incerto. Nós apresentamos neste estudo 11 pacientes com LMC tratados com o transplante autólogo (TMO-auto de CPP durante a fase crônica precoce, seguido de interferon-alfalfa (IFN-alfa. Amostras de medula óssea, obtidas ao diagn

  19. SIMPLANT: analytic calculation of ion implantation within the Tadpance system

    International Nuclear Information System (INIS)

    Fawcett, R.J.

    1988-04-01

    An analytic method for calculating the concentration distribution of dopant atoms introduced into a multilayer semiconductor device by ion beam implantation is explained. Computer software written to apply the method is described. The operation of the software within a semiconductor process and device modelling package is outlined. Implantation distributions generated by the software are illustrated. (author)

  20. Ion implantation for semiconductors

    International Nuclear Information System (INIS)

    Grey-Morgan, T.

    1995-01-01

    Full text: Over the past two decades, thousands of particle accelerators have been used to implant foreign atoms like boron, phosphorus and arsenic into silicon crystal wafers to produce special embedded layers for manufacturing semiconductor devices. Depending on the device required, the atomic species, the depth of implant and doping levels are the main parameters for the implantation process; the selection and parameter control is totally automated. The depth of the implant, usually less than 1 micron, is determined by the ion energy, which can be varied between 2 and 600 keV. The ion beam is extracted from a Freeman or Bernas type ion source and accelerated to 60 keV before mass analysis. For higher beam energies postacceleration is applied up to 200 keV and even higher energies can be achieved by mass selecting multiplycharged ions, but with a corresponding reduction in beam output. Depending on the device to be manufactured, doping levels can range from 10 10 to 10 15 atoms/cm 2 and are controlled by implanter beam currents in the range up to 30mA; continuous process monitoring ensures uniformity across the wafer of better than 1 % . As semiconductor devices get smaller, additional sophistication is required in the design of the implanter. The silicon wafers charge electrically during implantation and this charge must be dissipated continuously to reduce the electrical stress in the device and avoid destructive electrical breakdown. Electron flood guns produce low energy electrons (below 10 electronvolts) to neutralize positive charge buildup and implanter design must ensure minimum contamination by other isotopic species and ensure low internal sputter rates. The pace of technology in the semiconductor industry is such that implanters are being built now for 256 Megabit circuits but which are only likely to be widely available five years from now. Several specialist companies manufacture implanter systems, each costing around US$5 million, depending on the

  1. Scalloped Implant-Abutment Connection Compared to Conventional Flat Implant-Abutment Connection

    DEFF Research Database (Denmark)

    Starch-Jensen, Thomas; Christensen, Ann-Eva; Lorenzen, Henning

    2017-01-01

    OBJECTIVES: The objective was to test the hypothesis of no difference in implant treatment outcome after installation of implants with a scalloped implant-abutment connection compared to a flat implant-abutment connection. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane library search...... of suprastructures has never been compared within the same study. High implant survival rate was reported in all the included studies. Significantly more peri-implant marginal bone loss, higher probing depth score, bleeding score and gingival score was observed around implants with a scalloped implant-abutment...... loss around implants with a scalloped implant-abutment connection. CONCLUSIONS: A scalloped implant-abutment connection seems to be associated with higher peri-implant marginal bone loss compared to a flat implant-abutment connection. Therefore, the hypothesis of the present systematic review must...

  2. A temperature sensor implant for active implantable medical devices for in vivo subacute heating tests under MRI.

    Science.gov (United States)

    Silemek, Berk; Acikel, Volkan; Oto, Cagdas; Alipour, Akbar; Aykut, Zaliha Gamze; Algin, Oktay; Atalar, Ergin

    2018-05-01

    To introduce a temperature sensor implant (TSI) that mimics an active implantable medical device (AIMD) for animal testing of MRI heating. Computer simulations and phantom experiments poorly represent potential temperature increases. Animal experiments could be a better model, but heating experiments conducted immediately after the surgery suffer from alterations of the thermoregulatory and tissue properties during acute testing conditions. Therefore, the aim of this study was to introduce a temperature sensor implant that mimics an AIMD and capable of measuring the electrode temperature after implantation of the device without any further intervention at any time after the surgery in an animal model. A battery-operated TSI, which resembled an AIMD, was used to measure the lead temperature and impedance and the case temperature. The measured values were transmitted to an external computer via a low-power Bluetooth communication protocol. In addition to validation experiments on the phantom, a sheep experiment was conducted to test the feasibility of the system in subacute conditions. The measurements had a maximum of 0.5°C difference compared to fiber-optic temperature probes. In vivo animal experiments demonstrated feasibility of the system. An active implant, which can measure its own temperature, was proposed to investigate implant heating during MRI examinations. Magn Reson Med 79:2824-2832, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

  3. Reliability of implant placement after virtual planning of implant positions using cone beam CT data and surgical (guide) templates.

    Science.gov (United States)

    Nickenig, Hans-Joachim; Eitner, Stephan

    2007-01-01

    We assessed the reliability of implant placement after virtual planning of implant positions using cone-beam CT data and surgical guide templates. A total of 102 patients (250 implants, 55.4% mandibular; mean patient age, 40.4 years) who had undergone implant treatment therapy in an armed forces dental clinic (Cologne, Germany) between July 1, 2005 and December 1, 2005. They were treated with a system that allows transfer of virtual planning to surgical guide templates. Only in eight cases the surgical guides were not used because a delayed implant placement was necessary. In four posterior mandibular cases, handling was limited because of reduced interocclusal distance, requiring 50% shortening of the drill guides. The predictability of implant size was high: only one implant was changed to a smaller diameter (because of insufficient bone). In all cases, critical anatomical structures were protected and no complications were detected in postoperative panoramic radiographs. In 58.1% (147) of the 250 implants, a flapless surgery plan was realized. Implant placement after virtual planning of implant positions using cone beam CT data and surgical templates can be reliable for preoperative assessment of implant size, position, and anatomical complications. It is also indicative of cases amenable to flapless surgery.

  4. Middle ear implants

    Directory of Open Access Journals (Sweden)

    K S Gangadhara Somayaji

    2013-01-01

    Full Text Available Hearing loss is becoming more common in the society living in cities with lot of background noise around, and frequent use of gadgets like mobile phones, MP3s, and IPods are adding to the problem. The loss may involve the conductive or perceptive pathway. Majority of the patients with conductive hearing loss will revert back to normal hearing levels with medical and/or surgical treatment. However, in sensorineural hearing loss, many factors are involved in the management. Though traditionally hearing aids in various forms are the most commonly used modality in managing these patients, there are some drawbacks associated with them. Implantable middle ear amplifiers represent the most recent breakthrough in the management of hearing loss. Middle ear implants are surgically implanted electronic devices that aim to correct hearing loss by stimulating the ossicular chain or middle ear. Of late, they are also being used in the management of congenital conductive hearing loss and certain cases of chronic otitis media with residual hearing loss. The article aims to provide general information about the technology, indications and contraindications, selection of candidates, available systems, and advantages of middle ear implants. (MEI

  5. Pacemaker dependency after transcatheter aortic valve implantation with the self-expanding Medtronic CoreValve System.

    Science.gov (United States)

    van der Boon, Robert M A; Van Mieghem, Nicolas M; Theuns, Dominic A; Nuis, Rutger-Jan; Nauta, Sjoerd T; Serruys, Patrick W; Jordaens, Luc; van Domburg, Ron T; de Jaegere, Peter P T

    2013-09-30

    To determine pacemaker (PM) dependency at follow-up visit in patients who underwent new permanent pacemaker implantation (PPI) following transcatheter aortic valve implantation (TAVI). Single center prospective observational study including 167 patients without previous PM implantation who underwent TAVI with the self-expanding Medtronic CoreValve System (MCS) between November 2005 and February 2011. PM dependency was defined by the presence of a high degree atrioventricular block (HDAVB; second [AV2] and third degree [AV3B]), or a slow (atrial fibrilation with slow response (n=1, 2.8%) and left bundle branch block (n=1, 2.8%). Long term follow-up was complete for all patients and ranged from 1 to 40 months (median (IQR): 11.5 (5.0-18.0 months). Of those patients with a HDAVB, 16 out of the 30 patients (53.3%) were PM independent at follow-up visit (complete or partial resolution of the AV conduction abnormality). Overall, 20 out of the 36 patients (55.6%) who received a new PM following TAVI were PM independent at follow-up. Partial and even complete resolution of peri-operative AV conduction abnormalities after MCS valve implantation occurred in more than half of the patients. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Experimental investigation of commercial small diameter dental implants in porcine mandibular segments.

    Science.gov (United States)

    Hasan, Istabrak; Heinemann, Friedhelm; Schwegmann, Monika; Keilig, Ludger; Stark, Helmut; Bourauel, Christoph

    2017-02-01

    Small diameter (mini) dental implants have become more popular in recent years as alternatives to classical implant treatment in clinical cases with critical bony situations. However, an in-depth scientific analysis of the mechanical and biomechanical effects of small diameter implants has not yet been published. The aim of the present study was to investigate experimentally different commercial mini implants by measuring their displacements under immediate loading. Twelve commercially available mini implants were measured. Implants were inserted into porcine mandibular segments and loaded by means of a predefined displacement of 0.5 mm of the loading system. The implants were loaded at an angle of 30° to the implant long axis using the self-developed biomechanical hexapod measurement system. Implant displacements were registered. The experimental results were compared to the numerical ones from a previous study. Measured implant displacements were within the range of 39-194 μm. A large variation in the displacements was obtained among the different implant systems due to the different designs and thread profiles. Comparing experimental and numerical results, the displacements that were obtained numerically were within the range of 79-347 μm. The different commercial mini implants showed acceptable primary stability and could be loaded immediately after their insertion.

  7. Comparison of two systems for rigidly connecting 2.0-mm bone screws to an implantable device : in vitro stability testing

    NARCIS (Netherlands)

    van Loon, JP; de Bont, LGM; Verkerke, GJ

    The stability of a screw-fixed implantable device can be improved by eliminating the freedom of movement between the screws and the device. Two systems have been developed for rigidly connecting 2.0-mm bone screws to an implantable device, and the aim of this study was to test and compare the

  8. The effects of local insulin application to lumbar spinal fusions in a rat model.

    Science.gov (United States)

    Koerner, John D; Yalamanchili, Praveen; Munoz, William; Uko, Linda; Chaudhary, Saad B; Lin, Sheldon S; Vives, Michael J

    2013-01-01

    The rates of pseudoarthrosis after a single-level spinal fusion have been reported up to 35%, and the agents that increase the rate of fusion have an important role in decreasing pseudoarthrosis after spinal fusion. Previous studies have analyzed the effects of local insulin application to an autograft in a rat segmental defect model. Defects treated with a time-released insulin implant had significantly more new bone formation and greater quality of bone compared with controls based on histology and histomorphometry. A time-released insulin implant may have similar effects when applied in a lumbar spinal fusion model. This study analyzes the effects of a local time-released insulin implant applied to the fusion bed in a rat posterolateral lumbar spinal fusion model. Our hypothesis was twofold: first, a time-released insulin implant applied to the autograft bed in a rat posterolateral lumbar fusion will increase the rate of successful fusion and second, will alter the local environment of the fusion site by increasing the levels of local growth factors. Animal model (Institutional Animal Care and Use Committee approved) using 40 adult male Sprague-Dawley rats. Forty skeletally mature Sprague-Dawley rats weighing approximately 500 g each underwent posterolateral intertransverse lumbar fusions with iliac crest autograft from L4 to L5 using a Wiltse-type approach. After exposure of the transverse processes and high-speed burr decortication, a Linplant (Linshin Canada, Inc., ON, Canada) consisting of 95% microrecrystalized palmitic acid and 5% bovine insulin (experimental group) or a sham implant consisting of only palmitic acid (control group) was implanted on the fusion bed with iliac crest autograft. As per the manufacturer, the Linplant has a release rate of 2 U/day for a minimum of 40 days. The transverse processes and autograft beds of 10 animals from the experimental and 10 from the control group were harvested at Day 4 and analyzed for growth factors. The

  9. Health-economic evaluation in implant trials: design considerations.

    Science.gov (United States)

    Alt, Volker; Pavlidis, Theodoros; Szalay, Gabor; Heiss, Christian; Schnettler, Reinhard

    2009-01-01

    In today's world, demonstration of the safety, efficacy, and quality of a new treatment strategy is no longer sufficient in many countries for market entry and reimbursement in the public healthcare system. This implies that new implants in orthopedic and orthopedic trauma surgery not only must be shown to lead to better medical outcome compared with the standard of care implant, but also must be shown to exhibit "good value" for the money for the public health-care system based on sound economic data from health-economic studies. The purpose of this article is to elucidate a framework for health-economic aspects alongside implant trials, with the assumption that the new implant is more costly but potentially better than the control implant. Cost-effectiveness, cost-utility, and cost-benefit studies are suitable for the assessment of the health-economic value of a new implant. The following criteria should be considered for a health-economic study design in the context with an implant: i) it should state medical benefits of the new implant compared with the control implant; ii) it should precise the type of health economic study; iii) it should define the methodological approach, perspective of the study, and types of costs; iv) if necessary, it should state discount costs and/benefits; and v) a sound sensitivity analysis should be included. Furthermore, close cooperation between researchers, clinicians, and health economists is essential.

  10. Biomechanical rationale and evaluation of an implant system for rib fracture fixation

    OpenAIRE

    Bottlang, M.; Walleser, S.; Noll, M.; Honold, S.; Madey, S. M.; Fitzpatrick, D.; Long, W. B.

    2010-01-01

    Background Biomechanical research directed at developing customized implant solutions for rib fracture fixation is essential to reduce the complexity and to increase the reliability of rib osteosynthesis. Without a simple and reliable implant solution, surgical stabilization of rib fractures will remain underutilized despite proven benefits for select indications. This article summarizes the research, development, and testing of a specialized and comprehensive implant solution for rib fractur...

  11. Five-Year Safety Data for More than 55,000 Subjects following Breast Implantation: Comparison of Rare Adverse Event Rates with Silicone Implants versus National Norms and Saline Implants.

    Science.gov (United States)

    Singh, Navin; Picha, George J; Hardas, Bhushan; Schumacher, Andrew; Murphy, Diane K

    2017-10-01

    The U.S. Food and Drug Administration has required postapproval studies of silicone breast implants to evaluate the incidence of rare adverse events over 10 years after implantation. The Breast Implant Follow-Up Study is a large 10-year study (>1000 U.S. sites) evaluating long-term safety following primary augmentation, revision-augmentation, primary reconstruction, or revision-reconstruction with Natrelle round silicone breast implants compared with national norms and outcomes with saline implants. Targeted adverse events in subjects followed for 5 to 8 years included connective tissue diseases, neurologic diseases, cancer, and suicide. The safety population comprised 55,279 women (primary augmentation, n = 42,873; revision-augmentation, n = 6837; primary reconstruction, n = 4828; and revision-reconstruction, n = 741). No targeted adverse events occurred at significantly greater rates in silicone implant groups versus national norms across all indications. The standardized incidence rate (observed/national norm) for all indications combined was 1.4 for cervical/vulvar cancer, 0.8 for brain cancer, 0.3 for multiple sclerosis, and 0.1 for lupus/lupus-like syndrome. Silicone implants did not significantly increase the risk for any targeted adverse events compared with saline implants. The risk of death was similar with silicone versus saline implants across all indications. The suicide rate (10.6 events per 100,000 person-years) was not significantly higher than the national norm. No implant-related deaths occurred. Results from 5 to 8 years of follow-up for a large number of subjects confirmed the safety of Natrelle round silicone implants, with no increased risk of systemic disease or suicide versus national norms or saline implants. Therapeutic, II.

  12. Surface modification of yttria stabilized zirconia by ion implantation

    International Nuclear Information System (INIS)

    Scholten, D.

    1987-01-01

    The results of investigations of surface modification by ion implantation in zirconia are described. As dopant material, iron was investigated thoroughly. The depth distribution of implanted ions depends on implantation parameters and the dopant-matrix system. The investigations of thermal stability of some implanted iron profiles by RBS and AES are described. Special interest lies in the thermal stability under working conditions of the zirconia material (400-1000 0 C). Radiation damage introduced in the implanted layer was investigated using transmission electron microscopy on polycrystalline material and channeling experiments on a single crystal implanted with iron. 179 refs.; 87 figs.; 20 tabs

  13. Revisiting the stability of mini-implants used for orthodontic anchorage

    Directory of Open Access Journals (Sweden)

    Chung-Chen Jane Yao

    2015-11-01

    Conclusion: This study revealed that once the dental surgeon becomes familiar with the procedure, the stability of orthodontic mini-implants depends on the type of mini-implant, age of the patient, implantation site, and the healing time of the mini-implant. Miniplates are a more feasible anchorage system when miniscrews fail repeatedly.

  14. Association between socioeconomic factors and ICD implantation in a publicly financed health care system

    DEFF Research Database (Denmark)

    Winther-Jensen, Matilde; Hassager, Christian; Lassen, Jens Flensted

    2017-01-01

    Aims: For patients surviving out-of-hospital cardiac arrest (OHCA) with a shockable rhythm, implantable cardioverter defibrillator (ICD) is recommended for non-reversible causes of arrest. We aimed to determine factors associated with implantation of ICD and survival in patients surviving non...... admission. Association to ICD implantation during index admission was analysed in logistic regression, survival was assessed using Cox regression. Implantable cardioverter defibrillator implantation increased during the study period [odds ratio (OR) 1-year increase: 1.04, 95% confidence intervals (95% CI...

  15. Chronically implanted pressure sensors: challenges and state of the field.

    Science.gov (United States)

    Yu, Lawrence; Kim, Brian J; Meng, Ellis

    2014-10-31

    Several conditions and diseases are linked to the elevation or depression of internal pressures from a healthy, normal range, motivating the need for chronic implantable pressure sensors. A simple implantable pressure transduction system consists of a pressure-sensing element with a method to transmit the data to an external unit. The biological environment presents a host of engineering issues that must be considered for long term monitoring. Therefore, the design of such systems must carefully consider interactions between the implanted system and the body, including biocompatibility, surgical placement, and patient comfort. Here we review research developments on implantable sensors for chronic pressure monitoring within the body, focusing on general design requirements for implantable pressure sensors as well as specifications for different medical applications. We also discuss recent efforts to address biocompatibility, efficient telemetry, and drift management, and explore emerging trends.

  16. Feasibility of a pre-implantation fitting test for an implantable hearing aid using a VR (virtual reality) software

    International Nuclear Information System (INIS)

    Dammann, F.; Bode, A.; Heuschmid, M.; Schwaderer, E.; Schaich, M.; Seemann, M.; Claussen, C.D.; Maassen, M.; Zenner, H.P.

    2001-01-01

    Purpose: To prove the feasibility of a preoperative fitting test for an implantable hearing aid using a VR environment. Methods: A high-resolution spiral CT was performed after mastoidectomy in 10 temporal bone specimens. The bony structures were segmented and merged with the computer-aided design (CAD) data of the hearing aid in a VR environment. For each specimen a three-dimensional fitting test was carried out by three examiners determining the implantability of the hearing aid. The implantation simulation was compared with the real implantation procedure performed by an experienced ENT surgeon. Results: The used VR system enabled real-time 3D-visualisation and manipulation of CT- and CAD-data. All objects could be independently moved in all three dimensions. The VR fitting test corresponded closely with the real implantation. The implantability of the hearing aid was properly predicted by all three examiners. Conclusion: Merging CT and CAD data in a virtual reality environment bears high potential for the presurgical determination of the fit and mountability of medical implants in complex anatomical regions. (orig.) [de

  17. Why are mini-implants lost: the value of the implantation technique!

    Science.gov (United States)

    Romano, Fabio Lourenço; Consolaro, Alberto

    2015-01-01

    The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1) Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2) Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3) Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4) The more precise the lancing procedures, the better the implant placement technique; 5) Self-drilling does not mean higher pressures; 6) Knowing where implant placement should end decreases the risk of complications and mini-implant loss.

  18. Why are mini-implants lost: The value of the implantation technique!

    Directory of Open Access Journals (Sweden)

    Fabio Lourenço Romano

    2015-02-01

    Full Text Available The use of mini-implants have made a major contribution to orthodontic treatment. Demand has aroused scientific curiosity about implant placement procedures and techniques. However, the reasons for instability have not yet been made totally clear. The aim of this article is to establish a relationship between implant placement technique and mini-implant success rates by means of examining the following hypotheses: 1 Sites of poor alveolar bone and little space between roots lead to inadequate implant placement; 2 Different sites require mini-implants of different sizes! Implant size should respect alveolar bone diameter; 3 Properly determining mini-implant placement site provides ease for implant placement and contributes to stability; 4 The more precise the lancing procedures, the better the implant placement technique; 5 Self-drilling does not mean higher pressures; 6 Knowing where implant placement should end decreases the risk of complications and mini-implant loss.

  19. Quality control of system of imaging for rectal ultrasound for implants seed prostate low rate

    International Nuclear Information System (INIS)

    Luquero Llopis, N.; Ferrer Gracia, C.; Huertas Martinez, C.; Huerga Cabrerizo, C.; Corredoira Silva, E.; Serrada Hierro, A.

    2013-01-01

    In this work, the objective is the evaluation of the image system used in implants of prostate of low rate held at our hospital, for maximum control on the placement of the seeds in the patient and therefore carried out dosimetry. (Author)

  20. Single-implant overdentures retained by the Novaloc attachment system: study protocol for a mixed-methods randomized cross-over trial.

    Science.gov (United States)

    de Souza, Raphael F; Bedos, Christophe; Esfandiari, Shahrokh; Makhoul, Nicholas M; Dagdeviren, Didem; Abi Nader, Samer; Jabbar, Areej A; Feine, Jocelyne S

    2018-04-23

    Overdentures retained by a single implant in the midline have arisen as a minimal implant treatment for edentulous mandibles. The success of this treatment depends on the performance of a single stud attachment that is susceptible to wear-related retention loss. Recently developed biomaterials used in attachments may result in better performance of the overdentures, offering minimal retention loss and greater patient satisfaction. These biomaterials include resistant polymeric matrixes and amorphous diamond-like carbon applied on metallic components. The objective of this explanatory mixed-methods study is to compare Novaloc, a novel attachment system with such characteristics, to a traditional alternative for single implants in the mandible of edentate elderly patients. We will carry out a randomized cross-over clinical trial comparing Novaloc attachments to Locators for single-implant mandibular overdentures in edentate elderly individuals. Participants will be followed for three months with each attachment type; patient-based, clinical, and economic outcomes will be gathered. A sample of 26 participants is estimated to be required to detect clinically relevant differences in terms of the primary outcome (patient ratings of general satisfaction). Participants will choose which attachment they wish to keep, then be interviewed about their experiences and preferences with a single implant prosthesis and with the two attachments. Data from the quantitative and qualitative assessments will be integrated through a mixed-methods explanatory strategy. A last quantitative assessment will take place after 12 months with the preferred attachment; this latter assessment will enable measurement of the attachments' long-term wear and maintenance requirements. Our results will lead to evidence-based recommendations regarding these systems, guiding providers and patients when making decisions on which attachment systems and implant numbers will be most appropriate for

  1. Implanted Antennas in Medical Wireless Communications

    CERN Document Server

    Rahmat-Samii, Yahya; Balanis, Constantine

    2006-01-01

    Implanted Antennas in Medical Wireless Communications summarizes the results of recent research activities on the subject of implanted antennas for medical wireless communication systems. It is anticipated that in the near future sophisticated medical devices will be implanted inside the human body for medical telemetry and telemedicine. To establish effective and efficient wireless links with these devices, it is pivotal to give special attention to antenna designs that are low profile, small, safe, and cost effective. In this book, authors Yahya Rahmat-Samii and Jaehoon Kim demonstrate how a

  2. Primary prevention of peri-implantitis: Managing peri-implant mucositis

    OpenAIRE

    Jepsen, Søren; Berglundh, Tord; Genco, Robert; Aass, Anne Merete; Demirel, Korkud; Derks, Jan; Figuero, Elena; Giovannoli, Jean Louis; Goldstein, Moshe; LAMBERT, France; Ortiz-Vigon, Alberto; Polyzois, Ioannis; Salvi, Giovanni; Schwarz, Frank; Serino, Giovanni

    2015-01-01

    Abstract AIMS: Over the past decades, the placement of dental implants has become a routine procedure in the oral rehabilitation of fully and partially edentulous patients. However, the number of patients/implants affected by peri-implant diseases is increasing. As there are--in contrast to periodontitis--at present no established and predictable concepts for the treatment of peri-implantitis, primary prevention is of key importance. The management of peri-implant mucositis is considere...

  3. Combined osteoplasty of metaepiphysial defects in total knee arthroplasty with osteoplastic biomaterial

    Directory of Open Access Journals (Sweden)

    Gavrilov М.А.

    2012-12-01

    Full Text Available The research goal is to study the results of osteoplastic biomaterials application to reach the improvement of primary and long-term secondary stability of fixation. Materials and methods: 62 patients with bone defect of metaepiphy-sis of type 2 according to AORI have been included into the research. Total knee arthroplasty with osteoplasty of the defect has been carried out in all the patients. In the basic group (n=32 combined osteoplasty has been used, and in comparison group (n=30 cement osteoplasty has been applied. In cases with total arthroplasty in the basic group modifying standard resections, structural autograft of laminar form has been received simultaneously. After preparing the floor of the defect its plasty has been carried out: in the basic group the defect has been filled with osteoconductive biomaterial, and in the comparison group — with polymethylmethacrylate to restore the anatomical configuration of condyles. Besides, before cement fixation of the prosthesis in the basic group the received autograft has been put on the restored implant plateau. Results: Assessing the results during the period from 2 to 4 years objective criteria have included the data of X-ray imaging, biomechanical research and WOMAC test. In the postoperative period significant differences have not been revealed. In the follow-up period in the group with application of the combined osteoplasty joint remodulation of autograft and osteoplastic biomaterial with regenerative restoration of bone tissue of the implant plateau has been observed. Conclusion: The described technique may reduce the relative risk of revision arthroplasty.

  4. Monitoring failure rates of commercial implant brands; substantial equivalence in question?

    Science.gov (United States)

    Hujoel, Philippe; Becker, William; Becker, Burton

    2013-07-01

    The aim of this study was to report on the failure rates of two distinct dental implant systems in a clinical practice setting. Date of implant placement and loss were entered prospectively in a data registry system. Failure rates of two commercially pure titanium implants, one with a porous oxydized surface (POS) and the other with a chemically altered surface (CAS), were assessed using a quality control chart and survival analyses. A total of 860 POS and 759 CAS implants were placed. A warning of an increased failure rate of the CAS implant was identified by means of the quality control chart. Survival analyses indicated that the CAS implant failure rate was twice that of the POS implant (Hazard Ratio: 2.08; 95% CI: 1.33-3.28, P-value POS implant was associated with a non-significant 64% drop in the implant failure rate within less than a year (HR: 0.36; 95% CI: 0.12-1.14; P-value POS implant and an 8% failure with the CAS implant appears inconsistent with the assumption of substantial equivalence. © 2012 John Wiley & Sons A/S.

  5. Osteogenesis and Morphology of the Peri-Implant Bone Facing Dental Implants

    Directory of Open Access Journals (Sweden)

    Marco Franchi

    2004-01-01

    Full Text Available This study investigated the influence of different implant surfaces on peri-implant osteogenesis and implant face morphology of peri-implant tissues during the early (2 weeks and complete healing period (3 months. Thirty endosseous titanium implants (conic screws with differently treated surfaces (smooth titanium = SS, titanium plasma sprayed = TPS, sand-blasted zirconium oxide = Zr-SLA were implanted in femur and tibiae diaphyses of two mongrel sheep. Histological sections of the implants and surrounding tissues obtained by sawing and grinding techniques were observed under light microscopy (LM. The peri-implant tissues of other samples were mechanically detached from the corresponding implants to be processed for SEM observation. Two weeks after implantation, we observed osteogenesis (new bone trabeculae around all implant surfaces only where a gap was present at the host bone-metal interface. No evident bone deposition was detectable where threads of the screws were in direct contact with the compact host bone. Distance osteogenesis predominated in SS implants, while around rough surfaces (TPS and Zr-SLA, both distance and contact osteogenesis were present. At SEM analysis 2 weeks after implantation, the implant face of SS peri-implant tissue showed few, thin, newly formed, bone trabeculae immersed in large, loose, marrow tissue with blood vessels. Around the TPS screws, the implant face of the peri-implant tissue was rather irregular because of the rougher metal surface. Zr-SLA screws showed more numerous, newly formed bone trabeculae crossing marrow spaces and also needle-like crystals in bone nodules indicating an active mineralising process. After 3 months, all the screws appeared osseointegrated, being almost completely covered by a compact, mature, newly formed bone. However, some marrow spaces rich in blood vessels and undifferentiated cells were in contact with the metal surface. By SEM analysis, the implant face of the peri-implant

  6. Amorphization of metals by ion implantation and ion beam mixing

    International Nuclear Information System (INIS)

    Rauschenbach, B.; Heera, V.

    1988-01-01

    Amorphous metallic systems can be formed either by high-fluence ion implantation of glassforming species or by irradiation of layered metal systems with inert gas ions. Both techniques and experimental examples are presented. Empirical rules are discussed which predict whether a given system can be transformed into an amorphous phase. Influence of temperature, implantation dose and pre-existing crystalline metal composition on amorphization is considered. Examples are given of the implantation induced amorphous structure, recrystallization and formation of quasicrystalline structures. (author)

  7. Implantable Medical Devices; Networking Security Survey

    Directory of Open Access Journals (Sweden)

    Siamak Aram

    2016-08-01

    Full Text Available The industry of implantable medical devices (IMDs is constantly evolving, which is dictated by the pressing need to comprehensively address new challenges in the healthcare field. Accordingly, IMDs are becoming more and more sophisticated. Not long ago, the range of IMDs’ technical capacities was expanded, making it possible to establish Internet connection in case of necessity and/or emergency situation for the patient. At the same time, while the web connectivity of today’s implantable devices is rather advanced, the issue of equipping the IMDs with sufficiently strong security system remains unresolved. In fact, IMDs have relatively weak security mechanisms which render them vulnerable to cyber-attacks that compromise the quality of IMDs’ functionalities. This study revolves around the security deficiencies inherent to three types of sensor-based medical devices; biosensors, insulin pump systems and implantable cardioverter defibrillators. Manufacturers of these devices should take into consideration that security and effectiveness of the functionality of implants is highly dependent on the design. In this paper, we present a comprehensive study of IMDs’ architecture and specifically investigate their vulnerabilities at networking interface.

  8. Labral reconstruction with iliotibial band autografts and semitendinosus allografts improves hip joint contact area and contact pressure: an in vitro analysis.

    Science.gov (United States)

    Lee, Simon; Wuerz, Thomas H; Shewman, Elizabeth; McCormick, Frank M; Salata, Michael J; Philippon, Marc J; Nho, Shane J

    2015-01-01

    Labral reconstruction using iliotibial band (ITB) autografts and semitendinosus (Semi-T) allografts has recently been described in cases of labral deficiency. To characterize the joint biomechanics with a labrum-intact, labrum-deficient, and labrum-reconstructed acetabulum in a hip cadaveric model. The hypothesis was that labral resection would decrease contact area, increase contact pressure, and increase peak force, while subsequent labral reconstruction with ITB autografts or Semi-T allografts would restore these values toward the native intact labral state. Controlled laboratory study. Ten fresh-frozen human cadaveric hips were analyzed utilizing thin-film piezoresistive load sensors to measure contact area, contact pressure, and peak force (1) with the native intact labrum, (2) after segmental labral resection, and (3) after graft labral reconstruction with either ITB autografts or Semi-T allografts. Each specimen was examined at 20° of extension and 60° of flexion. Statistical analysis was conducted through 1-way analysis of variance with post hoc Games-Howell tests. For the ITB group, labral resection significantly decreased contact area (at 20°: 73.2%±5.38%, P=.0010; at 60°: 78.5%±6.93%, P=.0063) and increased contact pressure (at 20°: 106.7%±4.15%, P=.0387; at 60°: 103.9%±1.15%, P=.0428). In addition, ITB reconstruction improved contact area (at 20°: 87.2%±12.3%, P=.0130; at 60°: 90.5%±8.81%, P=.0079) and contact pressure (at 20°: 98.5%±5.71%, P=.0476; at 60°: 96.6%±1.13%, P=.0056) from the resected state. Contact pressure at 60° of flexion was significantly lower compared with the native labrum (P=.0420). For the Semi-T group, labral resection significantly decreased contact area (at 20°: 68.1%±12.57%, P=.0002; at 60°: 67.5%±6.70%, P=.0002) and increased contact pressure (at 20°: 105.3%±3.73%, P=.0304; at 60°: 106.8%±4.04%, P=.0231). Semi-T reconstruction improved contact area (at 20°: 87.9%±7.95%, P=.0087; at 60°: 92.9%±13

  9. Three-Dimensional Finite Element Analysis on Stress Distribution of Internal Implant-Abutment Engagement Features.

    Science.gov (United States)

    Cho, Sung-Yong; Huh, Yun-Hyuk; Park, Chan-Jin; Cho, Lee-Ra

    To investigate the stress distribution in an implant-abutment complex with a preloaded abutment screw by comparing implant-abutment engagement features using three-dimensional finite element analysis (FEA). For FEA modeling, two implants-one with a single (S) engagement system and the other with a double (D) engagement system-were placed in the human mandibular molar region. Two types of abutments (hexagonal, conical) were connected to the implants. Different implant models (a single implant, two parallel implants, and mesial and tilted distal implants with 1-mm bone loss) were assumed. A static axial force and a 45-degree oblique force of 200 N were applied as the sum of vectors to the top of the prosthetic occlusal surface with a preload of 30 Ncm in the abutment screw. The von Mises stresses at the implant-abutment and abutment-screw interfaces were measured. In the single implant model, the S-conical abutment type exhibited broader stress distribution than the S-hexagonal abutment. In the double engagement system, the stress concentration was high in the lower contact area of the implant-abutment engagement. In the tilted implant model, the stress concentration point was different from that in the parallel implant model because of the difference in the bone level. The double engagement system demonstrated a high stress concentration at the lower contact area of the implant-abutment interface. To decrease the stress concentration, the type of engagement features of the implant-abutment connection should be carefully considered.

  10. Sub-meninges implantation reduces immune response to neural implants.

    Science.gov (United States)

    Markwardt, Neil T; Stokol, Jodi; Rennaker, Robert L

    2013-04-15

    Glial scar formation around neural interfaces inhibits their ability to acquire usable signals from the surrounding neurons. To improve neural recording performance, the inflammatory response and glial scarring must be minimized. Previous work has indicated that meningeally derived cells participate in the immune response, and it is possible that the meninges may grow down around the shank of a neural implant, contributing to the formation of the glial scar. This study examines whether the glial scar can be reduced by placing a neural probe completely below the meninges. Rats were implanted with sets of loose microwire implants placed either completely below the meninges or implanted conventionally with the upper end penetrating the meninges, but not attached to the skull. Histological analysis was performed 4 weeks following surgical implantation to evaluate the glial scar. Our results found that sub-meninges implants showed an average reduction in reactive astrocyte activity of 63% compared to trans-meninges implants. Microglial activity was also reduced for sub-meninges implants. These results suggest that techniques that isolate implants from the meninges offer the potential to reduce the encapsulation response which should improve chronic recording quality and stability. Published by Elsevier B.V.

  11. Polymeric implant of methylprednisolone for spinal injury ...

    African Journals Online (AJOL)

    Polymeric implant of methylprednisolone for spinal injury: preparation and characterization. Bo Yin, Jian-Jun Ji, Ming Yang. Abstract. Purpose: To improve the effectiveness and reduce the systemic side effects of methylprednisolone in traumatic spinal injuries, its polymeric implants were prepared using chitosan and sodium ...

  12. Quality assessment of pacemaker implantations in Denmark

    DEFF Research Database (Denmark)

    Møller, M; Arnsbo, P; Asklund, Mogens

    2002-01-01

    AIMS: Quality assessment of therapeutic procedures is essential to insure a cost-effective health care system. Pacemaker implantation is a common procedure with more than 500,000 implantations world-wide per year, but the general complication rate is not well described. We studied procedure relat...

  13. Progress in ion implantation equipment for semiconductor manufacturing

    International Nuclear Information System (INIS)

    Kawai, Tadashi; Naito, Masao

    1987-01-01

    In the semiconductor device manufacturing industry, ion implantation systems are used to dope semiconductor substrates with impurities that act as donor or acceptor. In an ion implantation system, required impurity ions are generated from an ion source, subjected to mass analysis, accelerated, converged and implanted in semiconductor wafers. High-tension arc tends to cause troubles in these systems, but improvement in design increased the average operation rate of medium-power systems from bout 70 percent to 90 percent during the past 10 years. Freeman type ion sources have replaced most RF ion sources and cold cathode PIG sources, which had been widely used until the early 1970s. Many of the recent ion sources are equipped with a P and As vaporizer to increase the beam intensity. By an increased beam intensity or decreased handling time in combination with an automatic handling system, the throughput has reached 330 wafers per hour for 10 second implantation. The yield has increased due to the development of improved scanning methods, vacuum devices such as cryopump, and processes and apparatus that serve for preventing particles from being contained in micro-devices. Various other improvements have been made to permit efficient production. (Nogami, K.)

  14. Scalloped Implant-Abutment Connection Compared to Conventional Flat Implant-Abutment Connection

    DEFF Research Database (Denmark)

    Starch-Jensen, Thomas; Christensen, Ann-Eva; Lorenzen, Henning

    2017-01-01

    OBJECTIVES: The objective was to test the hypothesis of no difference in implant treatment outcome after installation of implants with a scalloped implant-abutment connection compared to a flat implant-abutment connection. MATERIAL AND METHODS: A MEDLINE (PubMed), Embase and Cochrane library search......-abutment connection. There were no significant differences between the two treatment modalities regarding professional or patient-reported outcome measures. Meta-analysis disclosed a mean difference of peri-implant marginal bone loss of 1.56 mm (confidence interval: 0.87 to 2.25), indicating significant more bone...... loss around implants with a scalloped implant-abutment connection. CONCLUSIONS: A scalloped implant-abutment connection seems to be associated with higher peri-implant marginal bone loss compared to a flat implant-abutment connection. Therefore, the hypothesis of the present systematic review must...

  15. In Vitro Laser Treatment Platform Construction with Dental Implant Thread Surface on Bacterial Adhesion for Peri-Implantitis

    Directory of Open Access Journals (Sweden)

    Hsien-Nan Kuo

    2017-01-01

    Full Text Available This study constructs a standard in vitro laser treatment platform with dental implant thread surface on bacterial adhesion for peri-implantitis at different tooth positions. The standard clinical adult tooth jaw model was scanned to construct the digital model with 6 mm bone loss depth on behalf of serious peri-implantitis at the incisor, first premolar, and first molar. A cylindrical suite connected to the implant and each tooth root in the jaw model was designed as one experimental unit set to allow the suite to be replaced for individual bacterial adhesion. The digital peri-implantitis and suite models were exported to fulfill the physical model using ABS material in a 3D printer. A 3 mm diameter specimen implant on bacterial adhesion against Escherichia coli was performed for gram-negative bacteria. An Er:YAG laser, working with a chisel type glass tip, was moved from the buccal across the implant thread to the lingual for about 30 seconds per sample to verify the in vitro laser treatment platform. The result showed that the sterilization rate can reach 99.3% and the jaw model was not damaged after laser irradiation testing. This study concluded that using integrated image processing, reverse engineering, CAD system, and a 3D printer to construct a peri-implantitis model replacing the implant on bacterial adhesion and acceptable sterilization rate proved the feasibility of the proposed laser treatment platform.

  16. Imaging of common breast implants and implant-related complications: A pictorial essay.

    Science.gov (United States)

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  17. Immediate Direct-To-Implant Breast Reconstruction Using Anatomical Implants

    Directory of Open Access Journals (Sweden)

    Sung-Eun Kim

    2014-09-01

    Full Text Available BackgroundIn 2012, a new anatomic breast implant of form-stable silicone gel was introduced onto the Korean market. The intended use of this implant is in the area of aesthetic breast surgery, and many reports are promising. Thus far, however, there have been no reports on the use of this implant for breast reconstruction in Korea. We used this breast implant in breast reconstruction surgery and report our early experience.MethodsFrom November 2012 to April 2013, the Natrelle Style 410 form-stable anatomically shaped cohesive silicone gel-filled breast implant was used in 31 breasts of 30 patients for implant breast reconstruction with an acellular dermal matrix. Patients were treated with skin-sparing mastectomies followed by immediate breast reconstruction.ResultsThe mean breast resection volume was 240 mL (range, 83-540 mL. The mean size of the breast implants was 217 mL (range, 125-395 mL. Breast shape outcomes were considered acceptable. Infection and skin thinning occurred in one patient each, and hematoma and seroma did not occur. Three cases of wound dehiscence occurred, one requiring surgical intervention, while the others healed with conservative treatment in one month. Rippling did not occur. So far, complications such as capsular contracture and malrotation of breast implant have not yet arisen.ConclusionsBy using anatomic breast implants in breast reconstruction, we achieved satisfactory results with aesthetics better than those obtained with round breast implants. Therefore, we concluded that the anatomical implant is suitable for breast reconstruction.

  18. A protocol of rehabilitation after ACL reconstruction using a hamstring autograft in the first month after surgery--a preliminary report.

    Science.gov (United States)

    Biernat, Ryszard; Wołosewicz, Mariusz; Tomaszewski, Wiesław

    2007-01-01

    The purpose of this paper is to present a protocol of rehabilitation after ACL reconstruction using a hamstring autograft in the first month after surgery. The program enables the patient to return early to everyday activities (school, sedentary work) without crutches or a stabilizer. The program has been developed in accordance with rehabilitation protocols employed at Karolinska Institute in Sweden and Prof. Shelbourne's Clinic in the USA. The study group included 31 patients (18 men and 13 women). Patients rehabilitated in the Department according to our program achieved stable gait patterns and were able to step up and down within four to seven weeks. Early patient mobilization after ACL reconstruction is possible and does not cause any negative effects provided that the patient, doctor and physiotherapist cooperate very closely.

  19. Effects of ion implantation on charges in the silicon--silicon dioxide system

    International Nuclear Information System (INIS)

    Learn, A.J.; Hess, D.W.

    1977-01-01

    Structures consisting of thermally grown oxide on silicon were implanted with boron, arsenic, or argon ions. For argon implantation through oxides, an increased fixed oxide charge (Q/sub ss/) was observed with the increase being greater for than for silicon. This effect is attributed to oxygen recoil which produces additional excess ionized silicon in the oxide of a type similar to that arising in thermal oxidation. Fast surface state (N/sub st/) generation was also noted which in most cases obscured the Q/sub ss/ increase. Of various heat treatments tested, only a 900 degreeC anneal in hydrogen annihilated N/sub st/ and allowed Q/sub ss/ measurement. Such N/sub st/ apparently arises as a consequence of implantation damage at the silicon--silicon dioxide interface. With the exception of boron implantations into thick oxides or through aluminum electrodes, reduction of the mobile ionic charge (Q/sub o/) was achieved by implantation. The reduction again is presumably damage related and is not negated by high-temperature annealing but may be counterbalanced by aluminum incorporation in the oxide

  20. Prevention and management of cochlear implant infections.

    Science.gov (United States)

    Gluth, Michael B; Singh, Rajesh; Atlas, Marcus D

    2011-11-01

    Understanding the issues of infection related to an implantable medical device is crucial to all cochlear implant teams. Furthermore, given the risk of central nervous system complications and the relatively high quantity of underlying resource investment associated with cochlear implantation, the stakes of infection are high. The optimal strategies to prevent and manage such infections are still evolving as good-quality prospective data to guide such management decisions are not yet abundant within the medical literature and many recommendations are based on retrospective reviews or anecdotal evidence. We will outline a general strategy to deal with cochlear implant-related infection based on both the authors' experience and the published literature.

  1. A 60 keV implanter for metals

    International Nuclear Information System (INIS)

    Leutenecker, R.; Ryssel, H.; Zeller, K.-H.; Spoehrle, H.P.

    1985-01-01

    The design and preliminary performance data of a 60 keV high current implanter for the implantation of non-separated ion beams into metals are described. The target chamber accepts samples up to 70 cm in diameter and is equipped with holders to implant ball bearings, axles and other components which have to be rotated during implantation. Samples are mounted on a rugged table which can move up to 35 kg for +-35 cm in the x and y directions. The implanter, including the vacuum system, is completely computer controlled. The ion source is equipped with an oven having a maximum temperature of 1200 0 C and can deliver ion beams of nitrogen as well as different metal ions such as tin and silver with currents up to 10 mA. (Auth.)

  2. Stresses generated by two zygomatic implant placement techniques associated with conventional inclined anterior implants

    Directory of Open Access Journals (Sweden)

    Paulo H.T. Almeida

    2018-06-01

    Full Text Available Purpose: To make a comparative evaluation, by means of the finite element method, of the stress generated on supporting tissues and prosthetic system components, using zygomatic implants with the exteriorized and extramaxillary techniques, and different placement positions, associated either with inclined anterior implants, or those without inclination. Materials and methods: Eight (8 tridimensional models were created to represent the clinical situations being researched, using the dataset of scanned images of an edentulous model. The implants and prosthetic components were photographed on millimeter paper and inserted into Rhinoceros 3D modeling computer software. From the measurements made on the image, the virtual models were made. The application force was distributed on the occlusal surface of the working side of the left maxillary first molar, first and second premolars, and incisal regions of the central incisor, simulating the occlusal load during mastication, in a total of 150 N. Results: The extramaxillary technique presented considerable variation in increased tension on the prosthesis screws and bone tissue. In the exteriorized technique, the highest tension values occurred in the region of the ridge, and the lowest, on the zygomatic process; the absence of cantilever reduced the stress on bone tissue in almost all regions. Conclusion: The exteriorized technique was shown to be more favorable to the distribution of stresses on the micro-unit screws and bone tissue, with the model with zygomatic implant placed in the region of the first molar and inclined anterior implant presenting the best results. Keywords: Zygomatic implants, Atrophic maxilla, Finite element analysis, Cantilever, Inclined implant

  3. Implantable Cardiac Pacemakers – 50 Years from the First Implantation

    Directory of Open Access Journals (Sweden)

    Ratko Magjarević

    2010-01-01

    Overview: Development of implantable cardiac pacemaker was enabled by another important invention, the silicon transistor. h ough the invention of suitable lithium cells as appropriate power supply was essential for prolongation of battery life cycle and for increased reliability of pacemakers, main milestones in the development were associated with technological breakthroughs in electronics: from transistors, which introduced such features as small size and low power consumption, to hybrid and integrated circuits, which enabled programmability, microprocessors, which added more options in programming (multiprogrammability, diagnostics and telemetry, and the ICT (information communication technology that enabled physicians remote access to patients and interrogation of their implantable devices. Conclusions: Implantable pacemakers are reliable devices indicated for a wide range of dif erent therapies of cardiac rhythm disorders and heart failure. h ere is still a lot to learn about the physiology of a normal heart and even more about the failing heart. Modern pacemakers provide physicians valuable information from pacemakers’ memory via the built-in telemetry system. h ese information help physicians to better understand pathologic processes within the heart, thus contributing to the development of new ideas for treatment of diseases and for precise tailoring of the therapy to the patient’s needs. Although implantable pacemakers have reached the level of mature technology, they will continue to develop with therapies and diagnostics to facilitate a higher quality of life.

  4. Implants in free fibula flap supporting dental rehabilitation - Implant and peri-implant related outcomes of a randomized clinical trial.

    Science.gov (United States)

    Kumar, Vinay V; Ebenezer, Supriya; Kämmerer, Peer W; Jacob, P C; Kuriakose, Moni A; Hedne, Naveen; Wagner, Wilfried; Al-Nawas, Bilal

    2016-11-01

    The objective of this study was to assess the difference in success rates of implants when using two or four implant-supported-overdentures following segmental mandibular reconstruction with fibula free flap. This prospective, parallel designed, randomized clinical study was conducted with 1:1 ratio. At baseline, all participants already had segmental reconstruction of mandible with free fibula flap. The participants were randomized into two groups: Group-I received implant-supported-overdentures on two tissue-level implants and Group-II received implant-supported-overdentures on four tissue-level implants. Success rates of the implants were evaluated at 3 months, 6 months and 12 months following implant loading using marginal bone level changes as well as peri-implant indices (Buser et al., 1990). 52 patients were randomized into two treatment groups (26 each), out of which 18 patients (36 implants) of Group-I and 17 patients (68 implants) of Group-II were evaluated. One implant in Group-I was lost due to infective complications and one patient in the same group had superior barrel necrosis. There was a statistically significant increase at both time points (p = 0.03, p = 0.04 at 6 months, 12 months) in the amount of marginal bone loss in Group-I (0.4 mm, 0.5 mm at 6 months, 12 months) as compared to Group-II (0.1 mm, 0.2 mm at 6 months, 12 months). There were no clinically significant changes peri-implant parameters between both groups. Peri-implant soft tissue hyperplasia was seen in both groups, 32% of implants at 3-months, 26% at 6-months and 3% at 12-months follow-up. The results of this study show that patients with 2-implant-supported-overdentures had higher marginal bone loss as compared to patients with 4-implant-supported-overdentures. There were no clinically significant differences in peri-implant soft tissue factors in patients with 2- or 4-implant-supported-overdentures. Hyperplastic peri-implant tissues are common in the early implant

  5. Imaging of common breast implants and implant-related complications: A pictorial essay

    Directory of Open Access Journals (Sweden)

    Amisha T Shah

    2016-01-01

    Full Text Available The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  6. General Diseases Influence on Peri-Implantitis Development: a Systematic Review

    Directory of Open Access Journals (Sweden)

    Zygimantas Guobis

    2016-09-01

    Full Text Available Objectives: To systematically review the influence of systemic diseases or medications used in their treatment on the dental implant therapy success. Material and Methods: The search strategy was implemented on the National Library of Medicine database (MEDLINE (Ovid and EMBASE electronic databases between January 2006 and January 2016. Human studies with available English articles analysing the relationship between dental implant therapy success and systemic diseases, such as diabetes mellitus, AIDS/HIV, rheumatoid arthritis, osteoporosis, Crohn’s disease, cardiovascular diseases, scleroderma, Sjögren’s syndrome, lichen planus, ectodermal dysplasia, post-transplantation status, were included in present review according to the PRISMA guidelines. The review protocol was registered on PROSPERO system with the code CRD42016033662. Results: Present review included forty one retrospective and prospective follow-up studies, case-control studies, case report series and cohort studies. Despite some limitations this study reveals positive results of implantation in most systemic conditions that should be interpreted with caution. Influence of cardiovascular diseases on the dental implantation success should be explored deeply, because of controversial results and likelihood of comorbidity expressed by a history of cardiovascular diseases and periodontitis. There is only a weak relationship with bone density in osteoporosis and implant failure. All the other diseases did not show significant effect on implantation success. Conclusions: Recent studies with low strength of evidence and controversy show that systemic diseases may have potential effect on the success of implantation, but further detailed studies are needed to provide these findings.

  7. Impact of Intentional Overload on Joint Stability of Internal Implant-Abutment Connection System with Different Diameter.

    Science.gov (United States)

    Lee, Ji-Hye; Lee, Won; Huh, Yoon-Hyuk; Park, Chan-Jin; Cho, Lee-Ra

    2017-09-05

    To evaluate the axial displacement of the implant-abutment assembly of different implant diameter after static and cyclic loading of overload condition. An internal conical connection system with three diameters (Ø 4.0, 4.5, and 5.0) applying identical abutment dimension and the same abutment screw was evaluated. Axial displacement of abutment and reverse torque loss of abutment screw were evaluated under static and cyclic loading conditions. Static loading test groups were subjected to vertical static loading of 250, 400, 500, 600, 700, and 800 N consecutively. Cyclic loading test groups were subjected to 500 N cyclic loading to evaluate the effect of excessive masticatory loading. After abutment screw tightening for 30 Ncm, axial displacement was measured upon 1, 3, 10, and 1,000,000 cyclic loadings of 500 N. Repeated-measure ANOVA and 2-way ANOVA were used for statistical analysis (α = 0.05). The increasing magnitude of vertical load and thinner wall thickness of implant increased axial displacement of abutment and reverse torque loss of abutment screw (p < 0.05). Implants in the Ø 5.0 diameter group demonstrated significantly low axial displacement, and reverse torque loss after static loading than Ø 4.0 and Ø 4.5 diameter groups (p < 0.05). In the cyclic loading test, all diameter groups of implant showed significant axial displacement after 1 cycle of loading of 500 N (p < 0.05). There was no significant axial displacement after 3, 10, or 1,000,000 cycles of loading (p = 0.603). Implants with Ø 5.0 diameter demonstrated significantly low axial displacement and reverse torque loss after the cyclic and static loading of overload condition. © 2017 by the American College of Prosthodontists.

  8. Retrograde peri-implantitis

    Directory of Open Access Journals (Sweden)

    Mohamed Jumshad

    2010-01-01

    Full Text Available Retrograde peri-implantitis constitutes an important cause for implant failure. Retrograde peri-implantitis may sometimes prove difficult to identify and hence institution of early treatment may not be possible. This paper presents a report of four cases of (the implant placed developing to retrograde peri-implantitis. Three of these implants were successfully restored to their fully functional state while one was lost due to extensive damage. The paper highlights the importance of recognizing the etiopathogenic mechanisms, preoperative assessment, and a strong postoperative maintenance protocol to avoid retrograde peri-implant inflammation.

  9. Performance of conical abutment (Morse Taper) connection implants: a systematic review.

    Science.gov (United States)

    Schmitt, Christian M; Nogueira-Filho, Getulio; Tenenbaum, Howard C; Lai, Jim Yuan; Brito, Carlos; Döring, Hendrik; Nonhoff, Jörg

    2014-02-01

    In this systematic review, we aimed to compare conical versus nonconical implant-abutment connection systems in terms of their in vitro and in vivo performances. An electronic search was performed using PubMed, Embase, and Medline databases with the logical operators: "dental implant" AND "dental abutment" AND ("conical" OR "taper" OR "cone"). Names of the most common conical implant-abutment connection systems were used as additional key words to detect further data. The search was limited to articles published up to November 2012. Recent publications were also searched manually in order to find any relevant studies that might have been missed using the search criteria noted above. Fifty-two studies met the inclusion criteria and were included in this systematic review. As the data and methods, as well as types of implants used was so heterogeneous, this mitigated against the performance of meta-analysis. In vitro studies indicated that conical and nonconical abutments showed sufficient resistance to maximal bending forces and fatigue loading. However, conical abutments showed superiority in terms of seal performance, microgap formation, torque maintenance, and abutment stability. In vivo studies (human and animal) indicated that conical and nonconical systems are comparable in terms of implant success and survival rates with less marginal bone loss around conical connection implants in most cases. This review indicates that implant systems using a conical implant-abutment connection, provides better results in terms of abutment fit, stability, and seal performance. These design features could lead to improvements over time versus nonconical connection systems. © 2013 Wiley Periodicals, Inc.

  10. A controlled clinical trial of implant-retained mandibular overdentures : Clinical aspects

    NARCIS (Netherlands)

    Boerrigter, EM; VanOort, RP; Raghoebar, GM; Stegenga, B; Schoen, PJ; Boering, G

    In a controlled clinical trial, treatment effects of mandibular overdentures on two different implant-systems in edentulous patients were compared one year after insertion of the new dentures. The implant-systems used were the Branemark system (Bra) and the IMZ-system. Treatment was randomly

  11. Evaluation of an expence of materials during ion implantation

    International Nuclear Information System (INIS)

    Bannikov, M.G.; Zlobin, N.; Zotov, A.V.; Vasilev, V.I.; Vasilev, I.P.

    2003-01-01

    Ion implantation is used for a surface modification. The implantation dose must be sufficient to obtain the required properties of a processed surface, but should not be exceeded to prevent over-expenditure of implanted materials. The latter is especially important when noble metals are used as an implanted material. The ion implanter includes a vacuum chamber, source of metal ions (target) and a vacuum pumping-out system. Ions of a plasma-forming gas sputter the target and ions of metal are then accelerated and implanted into surface treated. Ion implantation dose can be calculated from operation parameters such as ion beam current density and duration of implanting. The presence of the plasma-forming gas in the ion flow makes it difficult to determine the expenditure of an implanted metal itself. The objective of this paper is the more accurate definition of an expense of an implanted metal. Mass- spectrometric analysis of an ion beam together with the weighing of the target was used to determine the expense of an implanted metal. It was found that, depending on the implantation parameters, on average around 50% of a total ion flow are metal ions. Results obtained allow more precise definition of an implantation dose. Thus, over- expenditure of implanted metals can be eliminated. (author)

  12. Low-Gain, Low-Noise Integrated Neuronal Amplifier for Implantable Artifact-Reduction Recording System

    Directory of Open Access Journals (Sweden)

    Abdelhamid Benazzouz

    2013-09-01

    Full Text Available Brain neuroprostheses for neuromodulation are being designed to monitor the neural activity of the brain in the vicinity of the region being stimulated using a single macro-electrode. Using a single macro-electrode, recent neuromodulation studies show that recording systems with a low gain neuronal amplifier and successive amplifier stages can reduce or reject stimulation artifacts. These systems were made with off-the-shelf components that are not amendable for future implant design. A low-gain, low-noise integrated neuronal amplifier (NA with the capability of recording local field potentials (LFP and spike activity is presented. In vitro and in vivo characterizations of the tissue/electrode interface, with equivalent impedance as an electrical model for recording in the LFP band using macro-electrodes for rodents, contribute to the NA design constraints. The NA occupies 0.15 mm2 and dissipates 6.73 µW, and was fabricated using a 0.35 µm CMOS process. Test-bench validation indicates that the NA provides a mid-band gain of 20 dB and achieves a low input-referred noise of 4 µVRMS. Ability of the NA to perform spike recording in test-bench experiments is presented. Additionally, an awake and freely moving rodent setup was used to illustrate the integrated NA ability to record LFPs, paving the pathway for future implantable systems for neuromodulation.

  13. Correlation between Insertion Torque and Implant Stability Quotient in Tapered Implants with Knife-Edge Thread Design

    Directory of Open Access Journals (Sweden)

    Domenico Baldi

    2018-01-01

    Full Text Available Aim. To evaluate the correlation between insertion torque (IT and implant stability quotient (ISQ in tapered implants with knife-edge threads. Methods. Seventy-five identical implants (Anyridge, Megagen were inserted by using a surgical drilling unit with torque control and an integrated resonance frequency analysis module (Implantmed, W&H. IT (N/cm and ISQ were recorded and implants were divided into three groups (n=25 according to the IT: low (50. ISQ difference among groups was assessed by Kruskal-Wallis test, followed by Bonferroni-corrected Mann–Whitney U-test for pairwise comparisons. The strength of the association between IT and ISQ was assessed by Spearman Rho correlation coefficient (α=0.05. Results. At the pairwise comparisons, a significant difference of ISQ values was demonstrated only between low torque and high torque groups. The strength of the association between IT and ISQ value was significant for both the entire sample and the medium torque group, while it was not significant in low and high torque groups. Conclusions. For the investigated implant, ISQ and IT showed a positive correlation up to values around 50 N/cm: higher torques subject the bone-implant system to unnecessary biological and mechanical stress without additional benefits in terms of implant stability. This trial is registered with NCT03222219.

  14. Systemic Assessment of Calcium and Phosphorus Level after Implantation of Porous Iron in Rats

    Science.gov (United States)

    Siallagan, S. F.; Amelia, F.; Utami, N. D.; Ulum, M. F.; Boediono, A.; Estuningsih, S.; Hermawan, H.; Noviana, D.

    2017-07-01

    One of important aspects in bone healing process is physiological level of calcium (Ca), and phosphorus (P) that can be altered by implantation of biodegradable porous iron. Therefore, this study aims to investigate the concentration of Ca, P and Ca/P ratio in the peripheral blood during the implantation period up to 4 months. Forty adult male Sprague Dawley rats were used and divided into 3 groups receiving different pore size of iron implants (pore size 450, 580, 800μm) and one group of sham. The implants (5x2x0.5mm) were inserted into flat bone defects at latero-medial of femoral bone. Blood sample was taken from ventral tail artery before and after 4 month of implantation. Calcium and P concentrations in the blood were determined by BA-88A Semi-Auto Chemistry Analyzer. Results showed that concentration of Ca and P are slightly higher after implantation than before implantation, except for the 450μm group. The Ca/P ratio before and after implantation was increased in the sham group, and decreased in the 450 and 800μm groups. Concentration of Ca, P and Ca/P ratio insignificantly change between before and 4 months after surgery in some groups.

  15. Development and evaluation of totally implantable ventricular assist system using a vibrating flow pump and transcutaneous energy transmission system with amorphous fibers.

    Science.gov (United States)

    Yambe, T; Hashimoto, H; Kobayashi, S; Sonobe, T; Naganuma, S; Nanka, S S; Matsuki, H; Yoshizawa, M; Tabayashi, K; Takayasu, H; Takeda, H; Nitta, S

    1997-01-01

    We have developed a vibrating flow pump (VFP) that can generate oscillated blood flow with a relatively high frequency (10-50 Hz) for a totally implantable ventricular assist system (VAS). To evaluate the newly developed VAS, left heart bypasses, using the VFP, were performed in chronic animal experiments. Hemodynamic parameters were recorded in a data recorder in healthy adult goats during an awake condition and analyzed in a personal computer system through an alternating-direct current converter. Basic performance of the total system with a transcutaneous energy transmission system were satisfactory. During left ventricular assistance with the VFP, Mayer wave fluctuations of hemodynamics were decreased in the power spectrum, the fractal dimensions of the hemodynamics were significantly decreased, and peripheral vascular resistance was significantly decreased. These results suggest that cardiovascular regulatory nonlinear dynamics, which mediate the hemodynamics, may be affected by left ventricular bypass with oscillated flow. The decreased power of the Mayer wave in the spectrum caused the limit cycle attractor of the hemodynamics and decreased peripheral resistance. These results suggest that this newly developed VAS is useful for the totally implantable system with unique characteristics that can control hemodynamic properties.

  16. Evaluation of electron beam stabilization for ion implant processing

    Science.gov (United States)

    Buffat, Stephen J.; Kickel, Bee; Philipps, B.; Adams, J.; Ross, Matthew F.; Minter, Jason P.; Marlowe, Trey; Wong, Selmer S.

    1999-06-01

    With the integration of high energy ion implant processes into volume CMOS manufacturing, the need for thick resist stabilization to achieve a stable ion implant process is critical. With new photoresist characteristics, new implant end station characteristics arise. The resist outgassing needs to be addressed as well as the implant profile to ensure that the dosage is correct and the implant angle does not interfere with other underlying features. This study compares conventional deep-UV/thermal with electron beam stabilization. The electron beam system used in this study utilizes a flood electron source and is a non-thermal process. These stabilization techniques are applied to a MeV ion implant process in a CMOS production process flow.

  17. Cochlear implants in children implanted in Jordan: A parental overview.

    Science.gov (United States)

    Alkhamra, Rana A

    2015-07-01

    Exploring the perspective of parents on the cochlear implant process in Jordan. Sixty parents of deaf children were surveyed on the information gathering process prior to cochlear implant surgery, and their implant outcome expectations post-surgery. Whether child or parent characteristics may impact parents' post-surgical expectations was explored. Although parents used a variety of information sources when considering a cochlear implant, the ear, nose and throat doctor comprised their major source of information (60%). Parents received a range of information prior to cochlear implant but agreed (93.3%) on the need for a multidisciplinary team approach. Post-surgically, parents' expected major developments in the areas of spoken language (97%), and auditory skills (100%). Receiving education in mainstream schools (92%) was expected too. Parents perceived the cochlear implant decision as the best decision they can make for their child (98.3%). A significant correlation was found between parents contentment with the cochlear implant decision and expecting developments in the area of reading and writing (r=0.7). Child's age at implantation and age at hearing loss diagnosis significantly affected parents' post-implant outcome expectations (pparents agree on the need for a comprehensive multidisciplinary team approach during the different stages of the cochlear implant process. Parents' education about cochlear implants prior to the surgery can affect their post-surgical outcome expectations. The parental perspective presented in this study can help professionals develop better understanding of parents' needs and expectations and henceforth improve their services and support during the different stages of the cochlear implant process. Copyright © 2015. Published by Elsevier Ireland Ltd.

  18. Location of unaccessible implant surface areas during debridement in simulated peri-implantitis therapy.

    Science.gov (United States)

    Steiger-Ronay, Valerie; Merlini, Andrea; Wiedemeier, Daniel B; Schmidlin, Patrick R; Attin, Thomas; Sahrmann, Philipp

    2017-11-28

    An in vitro model for peri-implantitis treatment was used to identify areas that are clinically difficult to clean by analyzing the pattern of residual stain after debridement with commonly employed instruments. Original data from two previous publications, which simulated surgical (SA) and non-surgical (NSA) implant debridement on two different implant systems respectively, were reanalyzed regarding the localization pattern of residual stains after instrumentation. Two blinded examiners evaluated standardized photographs of 360 initially ink-stained dental implants, which were cleaned at variable defect angulations (30, 60, or 90°), using different instrument types (Gracey curette, ultrasonic scaler or air powder abrasive device) and treatment approaches (SA or NSA). Predefined implant surface areas were graded for residual stain using scores ranging from one (stain-covered) to six (clean). Score differences between respective implant areas were tested for significance by pairwise comparisons using Wilcoxon-rank-sum-tests with a significance level α = 5%. Best scores were found at the machined surface areas (SA: 5.58 ± 0.43, NSA: 4.76 ± 1.09), followed by the tips of the threads (SA: 4.29 ± 0.44, NSA: 4.43 ± 0.61), and areas between threads (SA: 3.79 ± 0.89, NSA: 2.42 ± 1.11). Apically facing threads were most difficult to clean (SA: 1.70 ± 0.92, NSA: 2.42 ± 1.11). Here, air powder abrasives provided the best results. Machined surfaces at the implant shoulder were well accessible and showed least amounts of residual stain. Apically facing thread surfaces constituted the area with most residual stain regardless of treatment approach.

  19. Peri-Implant Bone Loss and Peri-Implantitis: A Report of Three Cases and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Vanchit John

    2016-01-01

    Full Text Available Dental implant supported restorations have been added substantially to the clinical treatment options presented to patients. However, complications with these treatment options also arise due to improper patient selection and inadequate treatment planning combined with poor follow-up care. The complications related to the presence of inflammation include perimucositis, peri-implant bone loss, and peri-implantitis. Prevalence rates of these complications have been reported to be as high as 56%. Treatment options that have been reported include nonsurgical therapy, the use of locally delivered and systemically delivered antibiotics, and surgical protocols aimed at regenerating the lost bone and soft tissue around the implants. The aim of this article is to report on three cases and review some of the treatment options used in their management.

  20. The effect of shape, length and diameter of implants on primary stability based on resonance frequency analysis

    Directory of Open Access Journals (Sweden)

    Hamidreza Barikani

    2014-01-01

    Full Text Available Background: The aim of this in vitro study was to evaluate the effect of shape, diameter and length of implants on their primary stability based on resonance frequency analysis. Materials and Methods: Replace select tapered and Branemark MK III implants were selected. Each of these two selected groups was divided into nine subgroups based on the implant length (IL (short, medium and long and the implant diameter (ID (narrow platform [NP], regular platform [RP] and wide platform [WP]. Five implants were assigned to each of the nine subgroups. Implants were placed in artificial bone blocks with bone quality similar to D3 bone. Immediately after the implant placement, its primary stability was measured using Osstell Mentor equipment. T-test and Tukey′s honest significant difference Post hoc were performed for data analysis. Statistical significance was defined at P < 0.05. Results: Replace select system showed significantly higher primary stability compared to the Branemark system, when using the short implants for all three diameters (P ≤ 0.004. However, in medium length implants there were no significant differences between the two implant systems (P ≥ 0.31. In long implants, only when the NP and RP implants were used, the Replace Select system showed significantly higher primary stability compared to the Branemark system (P = 0.000. In the replace select system, long implants had a significantly higher primary stability compared to medium and short length implants (P ≤ 0.003. In the NP and RP Branemark implants, short implants showed significantly lower primary stability compared to medium and long implants (P ≤ 0.002. However, in WP Branemark implants, primary stability increased significantly with increasing the IL from short to medium and from medium to long (P = 0.000. There were also significant differences between NP and the two other wider implants in both systems (P = 0.000. Conclusion: The use of tapered implants is

  1. Long time follow up of implant therapy and treatment of peri-implantitis.

    Science.gov (United States)

    Roos-Jansåker, Ann-Marie

    2007-01-01

    Dental implants have become an often used alternative to replace missing teeth, resulting in an increasing percentage of the adult population with implant supported prosthesis. Although favourable long-term results of implant therapy have been reported, infections occur. Until recently few reports included data on peri-implant infections, possibly underestimating this complication of implant treatment. It is possible that some infections around implants develop slowly and that with time peri-implantitis will be a common complication to implant therapy as an increasing number of patients have had their implants for a long time (>10 years). Data on treatment of peri-implant lesions are scarce leaving the clinician with limited guidance regarding choice of treatment. The aim of this thesis was to study the frequency of implant loss and presence of peri-implant lesions in a group of patients supplied with Brånemark implants 9-14 years ago, and to relate these events to patient and site specific characteristics. Moreover three surgical treatment modalities for peri-implantitis were evaluated. The thesis is based on six studies; Studies I-III included 218 patients and 1057 implants followed for 9-14 years evaluating prevalence of, and factors related to implant loss (Paper I) and prevalence of peri-implant infections and related factors (Paper I-III). Study IV is a review describing different treatment modalities of peri-implant infections. Study V is a prospective cohort study involving 36 patients and 65 implants, evaluating the use of a bone substitute with or without the use of a resorbable membrane. Study VI is a case series with 12 patients and 16 implants, evaluating a bone substitute in combination with a resorbable membrane and submerged healing. This thesis demonstrated that: After 9-14 years the survival rates of dental implants are high (95.7%). Implant loss seems to cluster within patients and are related to periodontitis evidenced as bone loss on

  2. Silicone breast implants and connective tissue disease

    DEFF Research Database (Denmark)

    Lipworth, Loren; Holmich, Lisbet R; McLaughlin, Joseph K

    2011-01-01

    The association of silicone breast implants with connective tissue diseases (CTDs), including systemic sclerosis, systemic lupus erythematosus, rheumatoid arthritis, and fibromyalgia, as well as a hypothesized new "atypical" disease, which does not meet established diagnostic criteria for any known...... CTD, has been extensively studied. We have reviewed the epidemiologic literature regarding an association between cosmetic breast implants and CTDs, with particular emphasis on results drawn from the most recent investigations, many of which are large cohort studies with long-term follow-up, as well...... as on those studies that address some of the misinformation and historically widespread claims regarding an association between breast implants and CTDs. These claims have been unequivocally refuted by the remarkably consistent evidence from published studies, as well as numerous independent meta...

  3. Oral Rehabilitation with Implant-Retained Overdenture in a Patient with Down Syndrome.

    Science.gov (United States)

    Altintas, Nuray Yilmaz; Kilic, Serdar; Altintas, Subutay Han

    2017-01-24

    Down syndrome, known as trisomy 21, is the most common chromosomal disorder. The disorder affects mental and systemic development as well as oral structure, including dental anomalies, high susceptibility of periodontal disease, and poor quality of alveolar bone. This report presents a case of dental rehabilitation by means of dental implants of a patient with Down syndrome. Two titanium dental implants were placed in the maxilla, and three titanium dental implants were installed in the mandible. One implant was lost during the osseointegration period. The prosthetic rehabilitation was performed with implant-retained maxillary and mandibular overdentures with the Locator attachment system. After a 2-year follow-up period, the patient was doing well, and all implants were clinically stable with no signs of bone loss or inflammation. The present study emphasizes that implant-retained overdentures with Locator attachment system could be a therapeutic option even for patients with Down syndrome. This therapy prevents crestal bone loss around the implants, improves functional and esthetic outcomes, and provides optimum oral hygiene for patients with mild mental impairment. Careful patient selection and education of patients and caregivers are essential considerations for a successful and safe treatment with dental implants in Down syndrome patients. © 2017 by the American College of Prosthodontists.

  4. Current concepts of regenerative biomaterials in implant dentistry

    Directory of Open Access Journals (Sweden)

    Annapurna Ahuja

    2015-01-01

    Full Text Available The primary objective of any implant system is to achieve firm fixation to the bone and this could be influenced by biomechanical as well as biomaterial selection. An array of materials is used in the replacement of missing teeth through implantation. The appropriate selection of biomaterials directly influences the clinical success and longevity of implants. Thus the clinician needs to have adequate knowledge of the various biomaterials and their properties for their judicious selection and application in his/her clinical practice. The recent materials such as bioceramics and composite biomaterials that are under consideration and investigation have a promising future. For optimal performance, implant biomaterials should have suitable mechanical strength, biocompatibility, and structural biostability in the physiological environment. This article reviews the various implant biomaterials and their ease of use in implant dentistry.

  5. The Effect of Breast Implants on Mammogram Outcomes.

    Science.gov (United States)

    Kam, Kelli; Lee, Esther; Pairawan, Seyed; Anderson, Kendra; Cora, Cherie; Bae, Won; Senthil, Maheswari; Solomon, Naveenraj; Lum, Sharon

    2015-10-01

    Breast cancer detection in women with implants has been questioned. We sought to evaluate the impact of breast implants on mammographic outcomes. A retrospective review of women undergoing mammography between March 1 and October 30, 2013 was performed. Demographic characteristics and mammogram results were compared between women with and without breast implants. Overall, 4.8 per cent of 1863 women identified during the study period had breast implants. Median age was 59 years (26-93). Women with implants were younger (53.9 vs 59.2 years, P breast tissue (72.1% vs 56.4%, P = 0.004) than those without. There were no statistically significant differences with regards to Breast Imaging Recording and Data System 0 score (13.3% with implants vs 21.4% without), call back exam (18.9% with vs 24.1% without), time to resolution of abnormal imaging (58.6 days with vs 43.3 without), or cancer detection rate (0% with implants vs 1.0% without). Because implants did not significantly affect mammogram results, women with implants should be reassured that mammography remains useful in detecting cancer. However, future research is required to determine whether lower call back rates and longer time to resolution of imaging findings contribute to delays in diagnosis in patients with implants.

  6. Anterior cruciate ligament reconstruction using bone plug-free quadriceps tendon autograft: intermediate-term clinical outcome after 24-36 months.

    Science.gov (United States)

    Schulz, Arndt P; Lange, Vivien; Gille, Justus; Voigt, Christine; Fröhlich, Susanne; Stuhr, Markus; Jürgens, Christian

    2013-01-01

    Although known as a possible graft option for decades, quadriceps tendon grafts have often been termed a second-line graft option. We report a consecutive case series using this method as the primary treatment line. The rationale for this study was to evaluate the midterm results of this method in a prospective and consecutive case series. The primary study question was to determine the clinical results 24-36 months after primary anterior cruciate ligament (ACL) reconstruction using a bone plug-free quadriceps tendon autograft fixed with bioabsorbable cross-pins. The study population included 55 patients, of whom 24 were female (43.6%). The mean age at the index procedure was 31.7 years (15-58 years). All patients received an ACL construction using a bone block-free quadriceps tendon graft fixed with resorbable cross-pins. The postoperative regimen included partial weight-bearing for 3 weeks and flexion limited to 90° for six weeks; an orthosis was not used. The mean follow-up duration was 29.5 months (24.3-38.5 months) after the index procedure. The International Knee Documentation Committee (IKDC) subjective score and examination form was assessed, as well as the Lysholm and Gillquist score and the Tegner activity index. The Rolimeter arthrometer was used to assess the anterior laxity of the knee. Graft harvesting was possible in all cases; a bony extension was never required. On average, graft length was measured at 8.8 cm (7.5-10 cm). The mean IKDC subjective score at follow-up was 80.44 points (55.17-100 points, standard deviation [SD] 12.05). The mean preinjury Tegner activity index was 4.98 (2-7) compared to a mean value of 4.16 (2-7, SD 0.8) at follow-up. There was a mean loss of 0.82 index points. The average Lysholm and Gillquist score was 89 points (65-100, SD 17.7). Of the results, 89.1% were in the good or very good groups; in one case (1.8%), the result was poor, while the rest were fair. ACL reconstruction using a bone plug-free quadriceps tendon

  7. Systemic Sclerosis and Silicone Breast Implant: A Case Report and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Antonios Psarras

    2014-01-01

    Full Text Available Environmentally induced systemic sclerosis is a well-recognized condition, which is correlated with exposure to various chemical compounds or drugs. However, development of scleroderma-like disease after exposure to silicone has always been a controversial issue and, over time, it has triggered spirited debate whether there is a certain association or not. Herein, we report the case of a 35-year-old female who developed Raynaud’s phenomenon and, finally, systemic sclerosis shortly after silicone breast implantation surgery.

  8. Electromechanical impedance method to assess dental implant stability

    International Nuclear Information System (INIS)

    Tabrizi, Aydin; Rizzo, Piervincenzo; Ochs, Mark W

    2012-01-01

    The stability of a dental implant is a prerequisite for supporting a load-bearing prosthesis and establishment of a functional bone–implant system. Reliable and noninvasive methods able to assess the bone interface of dental and orthopedic implants (osseointegration) are increasingly demanded for clinical diagnosis and direct prognosis. In this paper, we propose the electromechanical impedance method as a novel approach for the assessment of dental implant stability. Nobel Biocare ® implants with a size of 4.3 mm diameter ×13 mm length were placed inside bovine bones that were then immersed in a solution of nitric acid to allow material degradation. The degradation simulated the inverse process of bone healing. The implant–bone systems were monitored by bonding a piezoceramic transducer (PZT) to the implants’ abutment and measuring the admittance of the PZT over time. It was found that the PZT’s admittance and the statistical features associated with its analysis are sensitive to the degradation of the bones and can be correlated to the loss of calcium measured by means of the atomic absorption spectroscopy method. The present study shows promising results and may pave the road towards an innovative approach for the noninvasive monitoring of dental implant stability and integrity. (paper)

  9. Prosthetic implant treatment of the edentulous maxilla with overdenture.

    Science.gov (United States)

    Inversini, M

    2006-10-01

    The literature concerning the success of prosthetic implant treatment with maxillary overdenture is reviewed, and variables affecting treatment from the implant and prosthetic standpoint are analysed. Guidelines for the fabrication of maxillary overimplants comparable to those for mandibular overimplants are still lacking, as are evidence-based prosthetic design concepts. Individual methods and techniques have been described, but evaluation standards for the outcome of maxillary prosthetic-implant treatment are lacking or individually interpreted. The biomechanics involved in the proposed system are described, together with the advantages of telescopic crowns for the retention of removable partial prosthesis supported by maxillary implants. The positive influence, in terms of long-term prognosis, of the perio-protective design of removable partial prostheses supported by maxillary overimplants is also discussed. The proposed system not only provides stability, support and retention for removable partial prostheses supported by maxillary implants, but also enables implant survival rates to be improved, both for biomechanical reasons and due to improved oral hygiene. The simplification of fabrication procedures, repair, rebasing and re-operating also reduce the cost of follow-up and improve the cost/benefit ratio. However, additional studies are needed to clarify the number and most appropriate distribution of implants, as well as the most favourable prosthetic designs for maxillary overimplants.

  10. Breast reconstruction - implants

    Science.gov (United States)

    Breast implants surgery; Mastectomy - breast reconstruction with implants; Breast cancer - breast reconstruction with implants ... harder to find a tumor if your breast cancer comes back. Getting breast implants does not take as long as breast reconstruction ...

  11. Functional adaptation of the masticatory system to implant-supported mandibular overdentures.

    Science.gov (United States)

    Giannakopoulos, Nikolaos Nikitas; Corteville, Frédéric; Kappel, Stefanie; Rammelsberg, Peter; Schindler, Hans Jürgen; Eberhard, Lydia

    2017-05-01

    The purpose of this study was to investigate the adaptation behavior of the stomatognathic system after immediate loading (24 to 72 h after surgery) of two implants supporting mandibular overdentures, assessed on insertion and three months later. The study hypothesis was that insertion of the overdentures would significantly change masticatory performance and muscle activity at both times. Thirty subjects (nine female, mean age 69.64 ± 11.81 years; 21 male, mean age 68.67 ± 7.41 years) who participated in a randomized clinical trial were included in the study. Each patient was examined three times: (i) at baseline, after already having worn new dentures for three months (T1); (ii) immediately after insertion of the overdentures on the implants (T2); and (iii) after an adaptation period of three months (T3). Examination comprised assessment of masticatory performance with artificial test food (Optocal), and simultaneous bilateral surface EMG recording of the masseter and anterior temporalis muscles. Particle-size distribution (representative value X 50 ), maximum muscle contraction (MVC), and total muscle work (TMW; area under the curve) were compared by use of repeated-measures analysis of variance (ANOVA). At T3, all measured variables (i.e., masticatory performance and muscle activity) were significantly different from those at T1. At T2, no significant changes were observed. The study hypothesis had to be rejected for T2 but accepted for T3. Functional rehabilitation (in terms of masticatory performance and masticatory muscle activity) does not occur immediately after immediate loading of two implants with mandibular overdentures, but requires a significant time for functional improvement. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. [Operative treatment of proximal humeral four-part fractures in elderly patients: comparison of two angular-stable implant systems].

    Science.gov (United States)

    Kuhlmann, T; Hofmann, T; Seibert, O; Gundlach, G; Schmidt-Horlohé, K; Hoffmann, R

    2012-04-01

    Although being one of the most common fractures in elderly patients, there is still no standardised treatment protocol for four-part fractures of the proximal humerus. However, a wide variety of angular-stable implants is available. The present retrospective study compares the clinical and radiological outcome following operative treatment of four-part fractures of the proximal humerus with the Philos system (Philos, proximal humeral internal locking system, Synthes GmbH, Umkirch Germany) and the angular-stable Königsee plate system (Königsee Implantate GmbH, Allendorf, Germany) in patients older than 65 years. From July 2005 until December 2007 we identified 77 patients with a four-part fracture of the proximal humerus who were treated operatively with one of the two implant systems. Of the patients, 17 could not be located so that in total 60 patients (78 %) participated in this study. The mean age of the 30 patients (10 m, 20 f) in the Philos group was 69 years (65-92), whereas the mean age of the 30 patients (11 m, 19 f) in the Königsee group was 71 years (65-93). A comprehensive assessment was performed after a median of 17 months (12-24), including physical examination, radiographic examination and completion of the disabilities of the arm, shoulder and hand score (DASH) and the Constant score (CS) as patient-oriented, limb-specific questionnaires. Neither in the Philos nor in the Königsee group could excellent results be achieved. Using the CS 13 patients (43 %) of the Philos group achieved a good and 15 (50 %) a satisfactory result. Bad results were found in 2 patients (7 %). The mean CS was 61.53 points. In the Königsee group mean CS was 61.76 points. In detail, 14 patients (47 %) treated with the Königsee implant were rated as good and 15 (50 %) as satisfactory. Only 1 patient (3 %) was rated as poor. No significant statistical differences were found between the groups. Mean DASH score in the Philos group was 56.30 points and 55.37 points in the K

  13. Use of antibiotic beads to salvage infected breast implants.

    Science.gov (United States)

    Sherif, Rami D; Ingargiola, Michael; Sanati-Mehrizy, Paymon; Torina, Philip J; Harmaty, Marco A

    2017-10-01

    When an implant becomes infected, implant salvage is often performed where the implant is removed, capsulectomy is performed, and a new implant is inserted. The patient is discharged with a PICC line and 6-8 weeks of intravenous (IV) antibiotics. This method has variable success and subjects the patient to long-term systemic antibiotics. In the 1960s, the use of antibiotic-impregnated beads for the treatment of chronic osteomyelitis was described. These beads deliver antibiotic directly to the site of the infection, thereby eliminating the complications of systemic IV antibiotics. This study aimed to present a case series illustrating the use of STIMULAN calcium sulfate beads loaded with vancomycin and tobramycin to increase the rate of salvage of the infected implant and forgo IV antibiotics. A retrospective analysis was performed of patients who were treated at Mount Sinai Hospital for implant infection with salvage and antibiotic beads. Twelve patients were identified, 10 of whom had breast cancer. Comorbidities included hypertension, smoking, and immunocompromised status. Infections were noted anywhere from 5 days to 8 years postoperatively. Salvage was successful in 9 out of the 12 infected implants using antibiotic bead therapy without home IV antibiotics. The use of antibiotic beads is promising for salvaging infected breast implants without IV antibiotics. Seventy-five percent of the implants were successfully salvaged. Of the three patients who had unsalvageable implants, one was infected with antibiotic-resistant Rhodococcus that was refractory to bead therapy and one was noncompliant with postoperative instructions. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  14. Comparison of dual-time-constant and fast-acting automatic gain control (AGC) systems in cochlear implants.

    Science.gov (United States)

    Boyle, Patrick J; Büchner, Andreas; Stone, Michael A; Lenarz, Thomas; Moore, Brian C J

    2009-04-01

    Cochlear implants usually employ an automatic gain control (AGC) system as a first stage of processing. AGC1 was a fast-acting (syllabic) compressor. AGC2 was a dual-time-constant system; it usually performed as a slow-acting compressor, but incorporated an additional fast-acting system to provide protection from sudden increases in sound level. Six experienced cochlear-implant users were tested in a counterbalanced order, receiving one-month of experience with a given AGC type before switching to the other type. Performance was evaluated shortly after provision of a given AGC type and after one-month of experience with that AGC type. Questionnaires, mainly relating to listening in quiet situations, did not reveal significant differences between the two AGC types. However, fixed-level and roving-level tests of sentence identification in noise both revealed significantly better performance for AGC2. It is suggested that the poorer performance for AGC1 occurred because AGC1 introduced cross-modulation between the target speech and background noise, which made perceptual separation of the target and background more difficult.

  15. An Implanted, Stimulated Muscle Powered Piezoelectric Generator

    Science.gov (United States)

    Lewandowski, Beth; Gustafson, Kenneth; Kilgore, Kevin

    2007-01-01

    A totally implantable piezoelectric generator system able to harness power from electrically activated muscle could be used to augment the power systems of implanted medical devices, such as neural prostheses, by reducing the number of battery replacement surgeries or by allowing periods of untethered functionality. The features of our generator design are no moving parts and the use of a portion of the generated power for system operation and regulation. A software model of the system has been developed and simulations have been performed to predict the output power as the system parameters were varied within their constraints. Mechanical forces that mimic muscle forces have been experimentally applied to a piezoelectric generator to verify the accuracy of the simulations and to explore losses due to mechanical coupling. Depending on the selection of system parameters, software simulations predict that this generator concept can generate up to approximately 700 W of power, which is greater than the power necessary to drive the generator, conservatively estimated to be 50 W. These results suggest that this concept has the potential to be an implantable, self-replenishing power source and further investigation is underway.

  16. Influence of implant number on the movement of mandibular implant overdentures.

    Science.gov (United States)

    Oda, Ken; Kanazawa, Manabu; Takeshita, Shin; Minakuchi, Shunsuke

    2017-03-01

    The rotational movement of an implant overdenture (IOD) has a negative effect on the perceived masticatory ability of the denture wearer. However, the influence of implant number on the movement of IODs has not been investigated. The purpose of this in vitro study was to evaluate the denture movement of mandibular IODs anchored by different numbers of implants. An edentulous mandibular test model with artificial mucosa and 5 experimental overdentures (N=5) was fabricated. The locator attachment system with blue nylon inserts was chosen for this study. Three implant positions were prepared: anterior midline (1-IOD), bilateral lateral incisor regions (2-IOD), and anterior midline and bilateral canine regions (3-IOD). Vertical loads of 50 N were applied to the mid-anterior region, the left canine region, the left premolar region, and the left first molar region. The vertical and horizontal displacements at the right distal edge and the vertical displacements at the loading point were measured. The displacement values were statistically analyzed using a 1-way analysis of variance and the post hoc Tukey honest significant difference test with the implant number as a factor. In addition, the values of the vertical and horizontal displacements at the distal edge of the overdenture were statistically compared using a paired t test, and the values of the vertical displacement at the distal edge of the overdenture were statistically analyzed by a repeated measures analysis of variance and the post hoc Tukey honest significance difference test with the loading point as a factor (a=.05). Upon anterior loading, the 2-IOD showed significantly larger vertical displacements at the right distal edge than the 1-IOD or 3-IOD (P.05). Within the limitations of this in vitro study, the following conclusions were drawn: During mastication with the anterior teeth, the use of 2 implants for anchoring an IOD increased the rotation of the denture base more than the use of 1 or 3 implants

  17. Device-length changes and implant function following surgical implantation of the KineSpring in cadaver knees

    Directory of Open Access Journals (Sweden)

    McNicholas MJ

    2015-01-01

    Full Text Available Michael J McNicholas,1 Stefan M Gabriel,2 Anton G Clifford,2 Evelyne M Hasler2 1Aintree University Hospital, Teaching Hospital, Major Trauma Centre, NHS Foundation Trust, Liverpool, UK; 2Moximed, Hayward, CA, USA Introduction: The KineSpring implant system has been shown to provide load reductions at the medial compartment of the knee, and has demonstrated clinical success in reducing pain and increasing function in patients with medial knee osteoarthritis. These results depend on the ability of the KineSpring to rotate, lengthen, and shorten to accommodate knee motions, and in response to knee position and loading. Purpose: The present study was undertaken to determine length changes of the implanted KineSpring in response to a range of knee positions, external knee loads, and placements by different orthopedic surgeons. Materials and methods: KineSpring system components were implanted in ten cadaver leg specimens by ten orthopedic surgeons, and absorber-length changes were measured under combined loading and in different positions of the knee. Results and conclusion: Spring compression consistent with knee-load reduction, and device lengthening and shortening to accommodate knee loads and motions were seen. These confirm the functionality of the KineSpring when implanted medially to the knee. Keywords: KineSpring, knee, function, preservation, offloading, osteoarthritis

  18. Dental Implants in an Aged Population: Evaluation of Periodontal Health, Bone Loss, Implant Survival, and Quality of Life.

    Science.gov (United States)

    Becker, William; Hujoel, Philippe; Becker, Burton E; Wohrle, Peter

    2016-06-01

    To evaluate aged partially and fully edentulous patients who received dental implants and were maintained over time. Further, to determine how the partially and edentulous ageing populations (65 and above) with dental implants maintain bone levels, proper oral hygiene, and perceive benefits of dental implants. Since 1995, patients receiving dental implants have been prospectively entered into an Access-based computerized program (Triton Tacking System). Patient demographics (age, sex), bone quality, quantity, implant location, and type of surgery have been continuously entered into the database. The database was queried for patients receiving implants (first stage) between 66 and 93 years of age. Thirty-one patients were within this age group. Twenty-five patients returned to the clinic for periodontal and dental implant evaluation. The Periodontal Index was used to evaluate selected teeth in terms of probing depth, bleeding on probing, plaque accumulation, and mobility. Using NIH Image J, radiographs taken at second stage and last examination were measured for changes in interproximal bone levels. Once identified, each patient anomalously filled out an abbreviated quality of health life form. Due to small sample size, descriptive statistics were used to compare clinical findings. Fifteen males ranging from 78 to 84 (mean age 84 years) years and 16 females from 66 to 93 (mean age 83 years) (age range 66-93) were contacted by phone or mail and asked to return to our office for a re-examination. For this group, the first dental implants were placed in 1996 (n = initial two implants) and continuously recorded through 2013 (n = last seven implants). Thirty-one patients received a total of 84 implants. Two patients were edentulous, and the remaining were partially edentulous. Four implants were lost. Between implant placement and 6- to 7-year interval, 13 patients with 40 implants had a cumulative survival rate of 94.6%. Of the original group (n = 33), three

  19. Remote actuated valve implant

    Science.gov (United States)

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  20. Technical tips during implantation of selective upper airway stimulation.

    Science.gov (United States)

    Heiser, Clemens; Thaler, Erica; Soose, Ryan J; Woodson, B Tucker; Boon, Maurits

    2018-03-01

    Selective upper airway stimulation is now well-established in the United States and in several European countries, with more than 1,000 patients implanted since U.S. Food and Drug Administration approval in April 2014. The authors herein, all head and neck surgeons, account for approximately one of every five implants completed to date. Several of the authors also provide comprehensive longitudinal care of their patients as dual-specialty sleep medicine physicians. Multi-center, retrospective clinical analysis. More than 300 implants have been evaluated and reviewed in five different implant centers (Germany, United States). This analysis shares tips and techniques from the collective experiences with more than 300 implants, which can help newer implanters learn vicariously both for standard practices in executing routine implants through activation and, importantly, for working through more challenging encounters with anatomy, special patient phenotypes, system testing, and troubleshooting. These tips should help new implanters handle most of the situations arising during implantation and avoid common pitfalls. Laryngoscope, 128:756-762, 2018. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  1. A 10-year randomized clinical trial on the influence of splinted and unsplinted oral implants retaining mandibular overdentures: peri-implant outcome.

    Science.gov (United States)

    Naert, Ignace; Alsaadi, Ghada; van Steenberghe, Daniel; Quirynen, Marc

    2004-01-01

    This randomized controlled clinical trial aimed to evaluate the efficacy of splinted implants versus unsplinted implants in overdenture therapy over a 10-year period. The study sample comprised 36 completely edentulous patients, 17 men and 19 women (mean age 63.7 years). In each patient, 2 implants (Brånemark System, Nobel Biocare, Göteborg, Sweden) were placed in the interforaminal area. Three to 5 months after placement, they were connected to standard abutments. The patients were then rehabilitated with ball-retained overdentures, magnet-retained overdentures, or bar-retained overdentures (the control group). Patients were followed for 4, 12, 60, and 120 months post-abutment connection. Group means as well as linear regression models were fitted with attachment type and time as classification variables and corrected for simultaneous testing (Tukey). After 10 years, 9 patients had died and 1 was severely ill. Over 10 years, no implants failed. Mean Plaque Index, Bleeding Index, change in attachment level, Periotest values, and marginal bone level at the end of the follow-up period were not significantly different among the groups. The annual marginal bone loss, excluding the first months of remodeling, was comparable with that found around healthy natural teeth. The fact that no implants failed and that overall marginal bone loss after the first year of bone remodeling was limited suggested that implants in a 2-implant mandibular overdenture concept have an excellent prognosis in this patient population, irrespective of the attachment system used.

  2. Dosimetric measurement of scattered radiation from dental implants in simulated head and neck radiotherapy.

    Science.gov (United States)

    Wang, R; Pillai, K; Jones, P K

    1998-01-01

    The purpose of this study was to examine the dose enhancement at bone-implant interfaces from scattered radiation during simulated head and neck radiotherapy. Three cylindric implant systems with different compositions (pure titanium, titanium-aluminum-vanadium alloy, titanium coated with hydroxyapatite) and a high gold content transmandibular implant system (gold-copper-silver alloy) were studied. Extruded lithium fluoride single crystal chips were used as thermoluminescent material to measure radiation dose enhancement at 0, 1, and 2 mm from the bone-implant interface. The relative doses in buccal, lingual, mesial, and distal directions were also recorded and compared. The results indicated that the highest dose enhancement occurred at a distance of 0 mm from the bone-implant interface for all the implant systems studied. The transmandibular implants had higher scattered radiation than other groups at 0 mm and at 1 mm from the bone-implant interface. There was no significant difference of dose enhancement between buccal, lingual, mesial, and distal directions. Titanium implants coated with hydroxyapatite demonstrated the best results under the simulated irradiation.

  3. [Carbon fiber-reinforced plastics as implant materials].

    Science.gov (United States)

    Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R

    2003-01-01

    Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

  4. ERP IMPLANTATION: KEY FACTORS OF SUCCESS AND IMPACT ON PERFORMANCE

    Directory of Open Access Journals (Sweden)

    Dumitru Valentin

    2008-05-01

    Full Text Available The implantation of an ERP (abbreviation for "Enterprise Resource Planning" system is an enterprise project that implies the remodeling of the information system, mostly the rethinking of management procedures within the organization. The expansion and the complexity of these projects demand a theoretical framework and « optimal practices » in order to model and to evaluate the key factors of implementation success and to analyze its impact on the organization’s performance. The research problem of our communication can be divided into three research questions: - What conceptual framework for ERP implantation? - What are the key factors of success in ERP implantation? - What is the relationship between ERP implantation and enterprise performance?

  5. Treatment Alternatives to Negotiate Peri-Implantitis

    Directory of Open Access Journals (Sweden)

    Eli E. Machtei

    2014-01-01

    Full Text Available Peri-implant diseases are becoming a major health issue in dentistry. Despite the magnitude of this problem and the potential grave consequences, commonly acceptable treatment protocols are missing. Hence, the present paper reviews the literature treatment of peri-implantitis in order to explore their benefits and limitations. Treatment of peri-implantitis may include surgical and nonsurgical approaches, either individually or combined. Nonsurgical therapy is aimed at removing local irritants from the implants’ surface with or without surface decontamination and possibly some additional adjunctive therapies agents or devices. Systemic antibiotics may also be incorporated. Surgical therapy is aimed at removing any residual subgingival deposits and additionally reducing the peri-implant pockets depth. This can be done alone or in conjunction with either osseous respective approach or regenerative approach. Finally, if all fails, explantation might be the best alternative in order to arrest the destruction of the osseous structure around the implant, thus preserving whatever is left in this site for future reconstruction. The available literature is still lacking with large heterogeneity in the clinical response thus suggesting possible underlying predisposing conditions that are not all clear to us. Therefore, at present time treatment of peri-implantitis should be considered possible but not necessarily predictable.

  6. Does the number of implants have any relation with peri-implant disease?

    Directory of Open Access Journals (Sweden)

    Bernardo Born PASSONI

    2014-10-01

    Full Text Available Objective: The aim of this study was to evaluate the relationship between the number of pillar implants of implant-supported fixed prostheses and the prevalence of periimplant disease. Material and Methods: Clinical and radiographic data were obtained for the evaluation. The sample consisted of 32 patients with implant-supported fixed prostheses in function for at least one year. A total of 161 implants were evaluated. Two groups were formed according to the number of implants: G1 ≤5 implants and G2 >5 implants. Data collection included modified plaque index (MPi, bleeding on probing (BOP, probing depth (PD, width of keratinized mucosa (KM and radiographic bone loss (BL. Clinical and radiographic data were grouped for each implant in order to conduct the diagnosis of mucositis or peri-implantitis. Results: Clinical parameters were compared between groups using Student’s t test for numeric variables (KM, PD and BL and Mann-Whitney test for categorical variables (MPi and BOP. KM and BL showed statistically significant differences between both groups (p<0.001. Implants from G1 – 19 (20.43% – compared with G2 – 26 (38.24% – showed statistically significant differences regarding the prevalence of peri-implantitis (p=0.0210. Conclusion: It seems that more than 5 implants in total fixed rehabilitations increase bone loss and consequently the prevalence of implants with periimplantitis. Notwithstanding, the number of implants does not have any influence on the prevalence of mucositis.

  7. Prospects of ion implantation and ion beam mixing for corrosion protection

    International Nuclear Information System (INIS)

    Wolf, G.K.; Munn, P.; Ensinger, W.

    1985-01-01

    Ion implantation is very useful new low temperature treatment for improving the mechanical surface properties of materials without any dimensional changes. In addition also the corrosion properties of metals can be modified considerably by this technique. The long term corrosion behaviour of implanted metals, however, has been studied only for a very limited number of cases. In this contribution a survey of attempts to do this will be presented. As examples of promising systems for corrosion protection by ion beams iron, steel and titanium were examined with and without pretreatment by ion implantation and ion beam mixing. The corrosion rates of the systems have been obtained by neutron activation analysis and by electrochemical methods. Experimental results are presented on: Palladium implanted in titanium - crevice corrosion in salt solution; Palladium implanted in and deposited on titanium -corrosion in sulfuric acid; Platinum implanted in stainless steel -corrosion in sulfuric acid. (author)

  8. Development and implantation of application systems for reduction and analysis of experimental data in Nuclear Physics area

    International Nuclear Information System (INIS)

    Cardoso Junior, J.L.; Schelin, H.R.; Lemos, B.J.K.C.; Tanaka, E.H.; Castro, A.T.C.G.

    1984-01-01

    Several application systems for reduction and analysis of experimental data are described. These codes were development and/or implanted in tee IEAv/CTA CYBER 170/750 system. A brief description of the experimental data acquisition modes and the necessary reduction for analysis is given. Information on the purposes, uses and access of the codes are given [pt

  9. Tribological properties of nitrogen implanted and boron implanted steels

    International Nuclear Information System (INIS)

    Kern, K.T.

    1996-01-01

    Samples of a steel with high chrome content was implanted separately with 75 keV nitrogen ions and with 75 keV boron ions. Implanted doses of each ion species were 2-, 4-, and 8 x 10 17 /cm 2 . Retained doses were measured using resonant non-Rutherford Backscattering Spectrometry. Tribological properties were determined using a pin-on-disk test with a 6-mm diameter ruby pin with a velocity of 0.94 m/min. Testing was done at 10% humidity with a load of 377 g. Wear rate and coefficient of friction were determined from these tests. While reduction in the wear rate for nitrogen implanted materials was observed, greater reduction (more than an order of magnitude) was observed for boron implanted materials. In addition, reduction in the coefficient of friction for high-dose boron implanted materials was observed. Nano-indentation revealed a hardened layer near the surface of the material. Results from grazing incidence x-ray diffraction suggest the formation of Fe 2 N and Fe 3 N in the nitrogen implanted materials and Fe 3 B in the boron implanted materials. Results from transmission electron microscopy will be presented

  10. Cochlear implantation in late-implanted adults with prelingual deafness.

    Science.gov (United States)

    Most, Tova; Shrem, Hadas; Duvdevani, Ilana

    2010-01-01

    The purpose of this study was to examine the effect of cochlear implantation (CI) on prelingually deafened participants who were implanted as adults. The effect of the CI was examined with regard to the following variables: communication, family, social skills, education, and work satisfaction with one's life, loneliness, and self-esteem. Thirty-eight adults participated. Four self-report questionnaires were used at 2 points in time: before and after CI. The research findings show significant differences in the reports of most variables before and after implantation. The participants felt better with regard to communication, social skills, education, and work and satisfaction with one's life after implantation in comparison to their feelings before implantation. Furthermore, they felt less lonely after implantation. However, there were no significant differences before and after implantation regarding their feelings within the family and regarding their self-esteem. The results demonstrated the need to evaluate the benefits resulting from the CI not only with traditional clinical measures but with additional measures as well. Furthermore, they demonstrated the benefit of the CI on the positive psychosociological implications of prelingually deafened adults. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Histology of a dental implant with a platform switched implant-abutment connection

    Directory of Open Access Journals (Sweden)

    Vittoria Perrotti

    2011-10-01

    Full Text Available Background: Peri-implant crestal bone must be stable for aesthetic reasons. Aim of this study was a histologic analysis of an implant with a platform switched implant-abutment connection. Materials and methods: A 32-year-old male patient participated in this study. The patient needed a bilateral mandibular restoration. Four implants were used, and were immediately restored and loaded the same day of insertion. After a 6 weeks healing period, one implant with platform-switched abutment was retrieved with trephine. Before retrieval the implant was osseointegrated and not mobile. On one side of the implant, a 1 mm resorption of the crestal bone was present. On the contrary, on the other side no bone resorption had occurred and about 1 mm of bone was present over the implant shoulder. Results: The bone-implant contact percentage was 65.1 ± 6.3 %. Platform- switching could help in maintaining the height of the peri-implant crestal bone.

  12. Safety of implantable pacemakers and cardioverter defibrillators in the magnetic field of a novel remote magnetic navigation system.

    Science.gov (United States)

    Jilek, Clemens; Tzeis, Stylianos; Reents, Tilko; Estner, Heidi-Luise; Fichtner, Stephanie; Ammar, Sonia; Wu, Jinjin; Hessling, Gabriele; Deisenhofer, Isabel; Kolb, Christof

    2010-10-01

    Electromagnetic interference with pacemaker and implantable cardioverter defibrillator (ICD) systems may cause temporary or permanent system malfunction of implanted devices. The aim of this study was to evaluate potential interference of a novel magnetic navigation system with implantable rhythm devices. A total of 121 devices (77 pacemakers, 44 ICDs) were exposed to an activated NIOBE II® Magnetic Navigation System (Stereotaxis, St. Louis, MO, USA) at the maximal magnetic field strength of 0.1 Tesla and evaluated in vitro with respect to changes in parameter settings of the device, changes of the battery status/detection of elective replacement indication, or alterations of data stored in the device. A total of 115 out of 121 (95%) devices were free of changes in parameter settings, battery status, and internally stored data after repeated exposition to the electromagnetic field of the remote magnetic navigation system. Interference with the magnetic navigation field was observed in 6 pacemakers, resulting in reprogramming to a power-on-reset mode with or without detection of the elective replacement indication in 5 devices and abnormal variance of battery status in one device. All pacemakers could be reprogrammed to the initial modes and the battery status proved to be normal some minutes after the pacemakers had been removed from the magnetic field. Interference of a remote magnetic navigation system (at maximal field strength) with pacemakers and ICDs not connected to leads with antitachycardic detection and therapies turned off is rare. Occurring functional abnormalities could be reprogrammed in our sample. An in vitro study will give information about interference of devices connected to leads. © 2010 Wiley Periodicals, Inc.

  13. Effectiveness of Implant Therapy Analyzed in a Swedish Population: Prevalence of Peri-implantitis.

    Science.gov (United States)

    Derks, J; Schaller, D; Håkansson, J; Wennström, J L; Tomasi, C; Berglundh, T

    2016-01-01

    Peri-implantitis is an inflammatory disease affecting soft and hard tissues surrounding dental implants. As the global number of individuals that undergo restorative therapy through dental implants increases, peri-implantitis is considered as a major and growing problem in dentistry. A randomly selected sample of 588 patients who all had received implant-supported therapy 9 y earlier was clinically and radiographically examined. Prevalence of peri-implantitis was assessed and risk indicators were identified by multilevel regression analysis. Forty-five percent of all patients presented with peri-implantitis (bleeding on probing/suppuration and bone loss >0.5 mm). Moderate/severe peri-implantitis (bleeding on probing/suppuration and bone loss >2 mm) was diagnosed in 14.5%. Patients with periodontitis and with ≥4 implants, as well as implants of certain brands and prosthetic therapy delivered by general practitioners, exhibited higher odds ratios for moderate/severe peri-implantitis. Similarly, higher odds ratios were identified for implants installed in the mandible and with crown restoration margins positioned ≤1.5 mm from the crestal bone at baseline. It is suggested that peri-implantitis is a common condition and that several patient- and implant-related factors influence the risk for moderate/severe peri-implantitis (ClinicalTrials.gov NCT01825772). © International & American Associations for Dental Research 2015.

  14. Reliability of a CAD/CAM Surgical Guide for Implant Placement: An In Vitro Comparison of Surgeons' Experience Levels and Implant Sites.

    Science.gov (United States)

    Park, Su-Jung; Leesungbok, Richard; Cui, Taixing; Lee, Suk Won; Ahn, Su-Jin

    This in vitro study evaluated the reliability of a surgical guide with regard to different levels of operator surgical experience and implant site. A stereolithographic surgical guide for epoxy resin mandibles with three edentulous molar sites was produced using a computer-aided design/computer-assisted manufacture (CAD/CAM) system. Two surgeons with and two surgeons without implant surgery experience placed implants in a model either using or not using the CAD/CAM surgical guide. Four groups were created: inexperienced surgeon without the guide (group 1); experienced surgeon without the guide (group 2); inexperienced surgeon with the guide (group 3); and experienced surgeon with the guide (group 4). Planned implants and placed implants were superimposed using digital software, and deviation parameters were calculated. There were no significant differences in any of the deviation parameters between the groups when using the surgical guide. With respect to the implant sites, there were no significant differences among the groups in any parameter. Use of the CAD/CAM surgical guide reduced discrepancies among operators performing implant surgery regardless of their level of experience. Whether or not the guide was used, differences in the anterior-posterior implant site in the molar area did not affect the accuracy of implant placement.

  15. Bilateral Poly Implant Prothèse Implant Rupture: An Uncommon Presentation

    Directory of Open Access Journals (Sweden)

    Peter Mallon

    2013-07-01

    Full Text Available Summary: A woman in her 50s underwent delayed bilateral Poly Implant Prothèse implant reconstruction following mastectomy for breast cancer. Symptoms of implant rupture developed 43 months after surgery with an erythematous rash on her trunk. The rash then spread to her reconstructed breast mounds. Initial ultrasound scan and magnetic resonance imaging were normal; however, subsequent magnetic resonance imaging demonstrated left implant rupture only. In theater, following removal of both implants, both were found to be ruptured. The rash on her trunk resolved within 3 weeks in the postoperative period. Chemical analyses of silicone in both implants confirmed a nonauthorized silicone source; in addition, the chemical structure was significantly different between the left and right implant, perhaps explaining the variation in presentation.

  16. Complications after cardiac implantable electronic device implantations

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  17. Management of peri-implantitis

    Directory of Open Access Journals (Sweden)

    Jayachandran Prathapachandran

    2012-01-01

    Full Text Available Peri-implantitis is a site-specific infectious disease that causes an inflammatory process in soft tissues, and bone loss around an osseointegrated implant in function. The etiology of the implant infection is conditioned by the status of the tissue surrounding the implant, implant design, degree of roughness, external morphology, and excessive mechanical load. The microorganisms most commonly associated with implant failure are spirochetes and mobile forms of Gram-negative anaerobes, unless the origin is the result of simple mechanical overload. Diagnosis is based on changes of color in the gingiva, bleeding and probing depth of peri-implant pockets, suppuration, X-ray, and gradual loss of bone height around the tooth. Treatment will differ depending upon whether it is a case of peri-implant mucositis or peri-implantitis. The management of implant infection should be focused on the control of infection, the detoxification of the implant surface, and regeneration of the alveolar bone. This review article deals with the various treatment options in the management of peri-implantitis. The article also gives a brief description of the etiopathogenesis, clinical features, and diagnosis of peri-implantitis.

  18. Peri-implant soft tissue and marginal bone adaptation on implant with non-matching healing abutments: micro-CT analysis.

    Science.gov (United States)

    Finelle, Gary; Papadimitriou, Dimitrios E V; Souza, André B; Katebi, Negin; Gallucci, German O; Araújo, Mauricio G

    2015-04-01

    To assess (i) the outcome of changing the horizontal-offset dimension on the peri-implant soft tissues and the crestal bone and (ii) the effect of different healing abutments (flared vs. straight) on the marginal peri-implant soft tissues and crestal bone. Two-piece dental implants diameters of 3.5 and 4.5 mm were placed at least 1 mm subcrestal in five beagle dogs. Three different investigational groups: (i) 3.5-mm-diameter implant with narrow healing abutment (3.5N), (ii) 4.5-mm-diameter implant with narrow healing abutment (4.5N), and (iii) 3.5-mm-diameter implant with wide healing abutment (3.5W), were assessed. After 4 months of healing, the vertical distance from the marginal crestal bone (MB) to the implant shoulder (IS); the vertical distance from the IS to the first bone-to-implant contact; and the horizontal distance of bone ingrowth on the implant platform were measured with a high-resolution micro-CT (Xradia MicroXCT-200 system). Implants with a narrow healing caps showed an interproximal MB located between 0 and 1 mm above the implant shoulder, while the 3.5W group exhibits a mean value -0.50 mm. As all implants in group 3.5N presented a fBIC located at the level of the IS. For the 4.5N group, the mean fBIC-IS distance was -0.52 mm apically to the IS. For the 3.5WC group, the mean fBIC-IS distance was -1.42 mm. Horizontal bone apposition was only observed for the 3.5N group and the 4.5N group. The dimension of the horizontal offset would play a minimal role in reducing bone remodeling, whereas the configuration of the transmucosal component would directly influence marginal bone remodeling. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Autologous Dermis Graft Implantation: A Novel Approach to Reinforcement in Giant Hiatal Hernias

    Directory of Open Access Journals (Sweden)

    Balázs Kovács

    2018-01-01

    Full Text Available Objectives. Nonreinforced tensile repair of giant hiatal hernias is susceptible to recurrence, and the role of mesh graft implantation remains controversial. Creating a new and viable choice without the use of high-cost biological allografts is desirable. This study presents the application of dermis graft reinforcement, a cost-efficient, easily adaptable alternative, in graft reinforcement of giant hiatal hernia repairs. Methods. A 62-year-old female patient with recurrent giant hiatal hernia (9 × 11 cm and upside down stomach, immediately following the Belsey repair done in another department, was selected for the pilot procedure. The standard three-stitch nonabsorbable reconstruction of diaphragmatic crura was undertaken via laparoscopic approach. A 12 × 6 cm dermis autograft was harvested from the loose abdominal skin. “U” figure onlay reinforcement of diaphragm closure was secured with titanium staples. The procedure was completed with a standard Dor fundoplication. One- and seven-month follow-ups were conducted. Results. No short-term postoperative complications were observed. One-month follow-up showed normal anatomical location of abdominal viscera on computed tomography imaging. High-resolution manometry showed normal lower esophageal sphincter pressure. Preoperative abdominal complaints were resolved. Procedural costs were lower than the average cost following mesh graft reinforcement. Conclusion. Dermis graft reinforcement is a cheap, easily adaptable procedure in the repair of giant hiatal hernias, even in the setting of laparoscopic reoperative procedure.

  20. Power Approaches for Implantable Medical Devices

    Directory of Open Access Journals (Sweden)

    Achraf Ben Amar

    2015-11-01

    Full Text Available Implantable medical devices have been implemented to provide treatment and to assess in vivo physiological information in humans as well as animal models for medical diagnosis and prognosis, therapeutic applications and biological science studies. The advances of micro/nanotechnology dovetailed with novel biomaterials have further enhanced biocompatibility, sensitivity, longevity and reliability in newly-emerged low-cost and compact devices. Close-loop systems with both sensing and treatment functions have also been developed to provide point-of-care and personalized medicine. Nevertheless, one of the remaining challenges is whether power can be supplied sufficiently and continuously for the operation of the entire system. This issue is becoming more and more critical to the increasing need of power for wireless communication in implanted devices towards the future healthcare infrastructure, namely mobile health (m-Health. In this review paper, methodologies to transfer and harvest energy in implantable medical devices are introduced and discussed to highlight the uses and significances of various potential power sources.

  1. Experimental study on bone tissue reaction around HA implants radiated after implantation

    International Nuclear Information System (INIS)

    Kudo, Masato; Matsui, Yoshiro; Tamura, Sayaka; Chen, Xuan; Uchida, Haruo; Mori, Kimie; Ohno, Kohsuke; Michi, Ken-ichi

    1998-01-01

    This study was conducted to investigate histologically and histomorphometrically the tissue reaction around hydroxylapatite (HA) implants that underwent irradiation in 3 different periods in the course of bone healing after implantation. The cylindrical high-density HA implants were implanted in 48 Japanese white rabbit mandibles. A single 15 Gy dose was applied to the mandible 5, 14, or 28 days after implantation. The rabbits were sacrificed 7, 14, 28, and 90 days after irradiation. Nonirradiated rabbits were used as controls. CMR, labeling with tetracycline and calcein, and non-decalcified specimens stained with toluidine blue were used for histological analyses and histomorphometric measurements. The results were as follows: In the rabbits irradiated 5 days after implantation, the HA-bone contact was observed later than that in the controls and the bone-implant contact surface ratio was lower than that in the controls at examination because necrosis of the newly-formed bone occurred just after irradiation. HA-bone contact of the rabbits irradiated 14 and 28 days after implantation was similar to that of the controls. And, bone remodeling was suppressed in rabbits of each group sacrificed at 90 days after irradiation. The results suggested that a short interval between implantation and irradiation causes direct contact between HA implant and bone and a long lapse of time before irradiation hardly affects the bone-implant contact, but delays bone remodeling. Therefore, it is necessary to prevent overloading the HA implants irradiated after implantation and pay utmost attention to conditions around the bone-implant contact. (author)

  2. Split-Framework in Mandibular Implant-Supported Prosthesis

    Directory of Open Access Journals (Sweden)

    Danny Omar Mendoza Marin

    2015-01-01

    Full Text Available During oral rehabilitation of an edentulous patient with an implant-supported prosthesis, mandibular flexure must be considered an important biomechanical factor when planning the metal framework design, especially if implants are installed posterior to the interforaminal region. When an edentulous mandible is restored with a fixed implant-supported prosthesis connected by a fixed full-arch framework, mandibular flexure may cause needless stress in the overall restorative system and lead to screw loosening, poor fit of prosthesis, loss of the posterior implant, and patient’s discomfort due to deformation properties of the mandible during functional movements. The use of a split-framework could decrease the stress with a precise and passive fit on the implants and restore a more natural functional condition of the mandible, helping in the longevity of the prosthesis. Therefore, the present clinical report describes the oral rehabilitation of an edentulous patient by a mandibular fixed implant-supported prosthesis with a split-framework to compensate for mandibular flexure. Clinical Significance. The present clinical report shows that the use of a split-framework reduced the risk of loss of the posterior implants or screws loosening with acceptable patient comfort over the period of a year. The split-framework might have compensated for the mandibular flexure during functional activities.

  3. Brainjacking: Implant Security Issues in Invasive Neuromodulation.

    Science.gov (United States)

    Pycroft, Laurie; Boccard, Sandra G; Owen, Sarah L F; Stein, John F; Fitzgerald, James J; Green, Alexander L; Aziz, Tipu Z

    2016-08-01

    The security of medical devices is critical to good patient care, especially when the devices are implanted. In light of recent developments in information security, there is reason to be concerned that medical implants are vulnerable to attack. The ability of attackers to exert malicious control over brain implants ("brainjacking") has unique challenges that we address in this review, with particular focus on deep brain stimulation implants. To illustrate the potential severity of this risk, we identify several mechanisms through which attackers could manipulate patients if unauthorized access to an implant can be achieved. These include blind attacks in which the attacker requires no patient-specific knowledge and targeted attacks that require patient-specific information. Blind attacks include cessation of stimulation, draining implant batteries, inducing tissue damage, and information theft. Targeted attacks include impairment of motor function, alteration of impulse control, modification of emotions or affect, induction of pain, and modulation of the reward system. We also discuss the limitations inherent in designing implants and the trade-offs that must be made to balance device security with battery life and practicality. We conclude that researchers, clinicians, manufacturers, and regulatory bodies should cooperate to minimize the risk posed by brainjacking. Copyright © 2016 Elsevier Inc. All rights reserved.

  4. One-stage explant-implant procedure of exposed porous orbital implants

    DEFF Research Database (Denmark)

    Toft, Peter B; Rasmussen, Marie L Roed; Prause, Jan Ulrik

    2011-01-01

    Purpose:  To investigate the risks of implant exposure after a combined explant-implant procedure in patients with an exposed porous orbital implant. Methods:  Twenty-four consecutive patients who had a combined explant-implant procedure of an exposed hydroxyapatite (21) or porous polyethylene (3...... at the same procedure in sockets without profound signs of infection. The procedure carries a possible risk of poor motility....

  5. Ion implantation as an efficient surface treatment

    International Nuclear Information System (INIS)

    Straede, C.A.

    1992-01-01

    Ion beam processing has for several years been well established in the semiconductor industry. In recent years ion implantation of tool steels, ceramics and even plastics has gained increasing industrial awareness. The development of ion implantation to a commercially viable surface treatment of tools and spare parts working in production type environments is very dependent on technical merits, economic considerations, competing processes and highly individual barriers to acceptance for each particular application. Some examples of this will be discussed. The development of the process is very closely linked with the development of high current accelerators and their ability to efficiently manipulate the samples being treated, or to make sample manipulation superfluous by using special beam systems like the PSII. Furthermore, the ability to produce high beam currents (mA) of a wide variety of ions is crucial. Previously, it was broadly accepted that ion implantation of tools on a commercial basis generally had to be limited to nitrogen implantation. The development of implanters which can produce high beam currents of ions like B + , C + , Ti + , Cr + and others is rapidly changing this situation, and today an increasing number of commercial implantations are performed with these ions although nitrogen is still successfully used in the majority of commercial implantation. All in all, the recent development of equipment makes it possible to a higher extent than before to tailor the implantation to a specific situation. The emerging new possibilities in this direction will be discussed, and a broad selection of practical examples of ion implantation at standard low temperatures of tools and spare parts will be given. Furthermore, very interesting results have been obtained recently by implanting nitrogen at elevated temperatures, which yields a relatively deep penetration of the implanted ions. (orig./WL)

  6. Successful vitrification and autografting of baboon (Papio anubis) ovarian tissue.

    Science.gov (United States)

    Amorim, Christiani A; Jacobs, Sophie; Devireddy, Ram V; Van Langendonckt, Anne; Vanacker, Julie; Jaeger, Jonathan; Luyckx, Valérie; Donnez, Jacques; Dolmans, Marie-Madeleine

    2013-08-01

    Can a vitrification protocol using an ethylene glycol/dimethyl sulphoxide-based solution and a cryopin successfully cryopreserve baboon ovarian tissue? Our results show that baboon ovarian tissue can be successfully cryopreserved with our vitrification protocol. Non-human primates have already been used as an animal model to test vitrification protocols for human ovarian tissue cryopreservation. Ovarian biopsies from five adult baboons were vitrified, warmed and autografted for 5 months. After grafting, follicle survival, growth and function and also the quality of stromal tissue were assessed histologically and by immunohistochemistry. The influence of the vitrification procedure on the cooling rate was evaluated by a computer model. After vitrification, warming and long-term grafting, follicles were able to grow and maintain their function, as illustrated by Ki67, anti-Müllerian hormone (AMH) and growth differentiation factor-9 (GDF-9) immunostaining. Corpora lutea were also observed, evidencing successful ovulation in all the animals. Stromal tissue quality did not appear to be negatively affected by our cryopreservation procedure, as demonstrated by vascularization and proportions of fibrotic areas, which were similar to those found in fresh ungrafted ovarian tissue. Despite our promising findings, before applying this technique in a clinical setting, we need to validate it by achieving pregnancies. In addition to encouraging results obtained with our vitrification procedure for non-human ovarian tissue, this study also showed, for the first time, expression of AMH and GDF-9 in ovarian follicles. This study was supported by grants from the Fonds National de la Recherche Scientifique de Belgique (grant Télévie No. 7.4507.10, grant 3.4.590.08 awarded to Marie-Madeleine Dolmans), Fonds Spéciaux de Recherche, Fondation St Luc, Foundation Against Cancer, and Department of Mechanical Engineering at Louisiana State University (support to Ram Devireddy), and

  7. Wireless power transfer and data communication for neural implants case study : epilepsy monitoring

    CERN Document Server

    Yilmaz, Gürkan

    2017-01-01

    This book presents new circuits and systems for implantable biomedical applications targeting neural recording. The authors describe a system design adapted to conform to the requirements of an epilepsy monitoring system. Throughout the book, these requirements are reflected in terms of implant size, power consumption, and data rate. In addition to theoretical background which explains the relevant technical challenges, the authors provide practical, step-by-step solutions to these problems. Readers will gain understanding of the numerical values in such a system, enabling projections for feasibility of new projects. Provides complete, system-level perspective for implantable batteryless biomedical system; Extends design example to implementation and long term in-vitro validation; Discusses system design concerns regarding wireless power transmission and wireless data communication, particularly for systems in which both are performed on the same channel/frequency; Presents fully-integrated, implantable syste...

  8. Spinal shape modulation in a porcine model by a highly flexible and extendable non-fusion implant system

    NARCIS (Netherlands)

    Wessels, Martijn; Hekman, Edsko E G; Kruyt, Moyo C.; Castelein, RM; Homminga, Jasper J.; Verkerke, Gijsbertus J.

    2016-01-01

    Purpose: In vivo evaluation of scoliosis treatment using a novel approach in which two posterior implants are implanted: XSLAT (eXtendable implant correcting Scoliosis in LAT bending) and XSTOR (eXtendable implant correcting Scoliosis in TORsion). The highly flexible and extendable implants use only

  9. The Pathology of Orthopedic Implant Failure Is Mediated by Innate Immune System Cytokines

    OpenAIRE

    Landgraeber, Stefan; Jäger, Marcus; Jacobs, Joshua J.; Hallab, Nadim James

    2014-01-01

    All of the over 1 million total joint replacements implanted in the US each year are expected to eventually fail after 15–25 years of use, due to slow progressive subtle inflammation at the bone implant interface. This inflammatory disease state is caused by implant debris acting, primarily, on innate immune cells, that is, macrophages. This slow progressive pathological bone loss or “aseptic loosening” is a potentially life-threatening condition due to the serious complications in older peop...

  10. Placement of fin type dental implant in three different surgical situations of alveolar bone

    Directory of Open Access Journals (Sweden)

    Coen Pramono D

    2007-03-01

    Full Text Available Three different dental implant placements according to surgical implant bed situations were observed in its bone integration 3 months after dental implant insertion. This observation was done on implant system which has plateau or fin system. Elf implants were placed in the upper jaw in two patients. In case one, two implants were inserted immediately after tooth extraction, and the other six implants were placed in the alveolar crest regions in delayed implantation or in which the teeth had been extracted over 6 months of period. In case two, three implants were inserted in the post trauma region in the anterior maxilla, which the labial plate had been lost and reconstructed with bone grafting procedure using a mixture of alloplastic and autogenous bones. The alveolar reconstruction was needed to be performed due to only thin alveolar crest width was left intact. All of those implants observed showed in good integration.

  11. [Electromagnetic fields of mobile telephone systems--thresholds, effects and risks for cochlear implant patients and healthy people].

    Science.gov (United States)

    Bischof, F; Langer, J; Begall, K

    2008-11-01

    Every day life is detectably affected by manifold natural sources of electromagnetic fields (EMF), e. g. infrared radiation, light and the terrestrial magnetic field. However, there is still uncertainty about the consequences or hazards of artificial EMF, which emerge from mobile phone or wireless network (wireless local area network [WLAN]) services, for instance. Following recommendations of the International Commission on Non-Ionizing Radiation Protection (ICNIRP) the German Commission on Radiation Protection (SSK) defined corresponding thresholds for high frequency electromagnetic fields (HF-EMF) in 2003. By observing those thresholds HF-EMF is thought to be innocent so far. However, there is still controversial discussion about induction of cancer or neurovegetative symptoms due to inconsistent study results. Patients with cochlea implants are of particular interest within the speciality of otorhinolaryngology due to specific hazards, which arise during mobile telephone use from the distance between brain and inductive metal implants (electrode) on the one hand and the electronic system of the cochlear implant and the source of HF-EMF on the other hand. Besides many studies about the impact of HF-EMF on common welfare, there are only very few surveys (n = 6) covering the effects on patients with cochlear implants. The purpose of this paper is to overview sources, thresholds and subsequently harmful or harmless effects of HFEMF. Due to the current state of knowledge about the impact of mobile phone use on health, we assume, that HF-EMF are harmless both for healthy people and patients with cochlea implants, provided that legal thresholds are observed.

  12. Toward a distributed free-floating wireless implantable neural recording system.

    Science.gov (United States)

    Pyungwoo Yeon; Xingyuan Tong; Byunghun Lee; Mirbozorgi, Abdollah; Ash, Bruce; Eckhardt, Helmut; Ghovanloo, Maysam

    2016-08-01

    To understand the complex correlations between neural networks across different regions in the brain and their functions at high spatiotemporal resolution, a tool is needed for obtaining long-term single unit activity (SUA) across the entire brain area. The concept and preliminary design of a distributed free-floating wireless implantable neural recording (FF-WINeR) system are presented, which can enabling SUA acquisition by dispersedly implanting tens to hundreds of untethered 1 mm3 neural recording probes, floating with the brain and operating wirelessly across the cortical surface. For powering FF-WINeR probes, a 3-coil link with an intermediate high-Q resonator provides a minimum S21 of -22.22 dB (in the body medium) and -21.23 dB (in air) at 2.8 cm coil separation, which translates to 0.76%/759 μW and 0.6%/604 μW of power transfer efficiency (PTE) / power delivered to a 9 kΩ load (PDL), in body and air, respectively. A mock-up FF-WINeR is implemented to explore microassembly method of the 1×1 mm2 micromachined silicon die with a bonding wire-wound coil and a tungsten micro-wire electrode. Circuit design methods to fit the active circuitry in only 0.96 mm2 of die area in a 130 nm standard CMOS process, and satisfy the strict power and performance requirements (in simulations) are discussed.

  13. Development of a simple, low cost, indirect ion beam fluence measurement system for ion implanters, accelerators

    Science.gov (United States)

    Suresh, K.; Balaji, S.; Saravanan, K.; Navas, J.; David, C.; Panigrahi, B. K.

    2018-02-01

    We developed a simple, low cost user-friendly automated indirect ion beam fluence measurement system for ion irradiation and analysis experiments requiring indirect beam fluence measurements unperturbed by sample conditions like low temperature, high temperature, sample biasing as well as in regular ion implantation experiments in the ion implanters and electrostatic accelerators with continuous beam. The system, which uses simple, low cost, off-the-shelf components/systems and two distinct layers of in-house built softwarenot only eliminates the need for costly data acquisition systems but also overcomes difficulties in using properietry software. The hardware of the system is centered around a personal computer, a PIC16F887 based embedded system, a Faraday cup drive cum monitor circuit, a pair of Faraday Cups and a beam current integrator and the in-house developed software include C based microcontroller firmware and LABVIEW based virtual instrument automation software. The automatic fluence measurement involves two important phases, a current sampling phase lasting over 20-30 seconds during which the ion beam current is continuously measured by intercepting the ion beam and the averaged beam current value is computed. A subsequent charge computation phase lasting 700-900 seconds is executed making the ion beam to irradiate the samples and the incremental fluence received by the sampleis estimated usingthe latest averaged beam current value from the ion beam current sampling phase. The cycle of current sampling-charge computation is repeated till the required fluence is reached. Besides simplicity and cost-effectiveness, other important advantages of the developed system include easy reconfiguration of the system to suit customisation of experiments, scalability, easy debug and maintenance of the hardware/software, ability to work as a standalone system. The system was tested with different set of samples and ion fluences and the results were verified using

  14. Clinical implementation of stereotaxic brain implant optimization

    International Nuclear Information System (INIS)

    Rosenow, U.F.; Wojcicka, J.B.

    1991-01-01

    This optimization method for stereotaxic brain implants is based on seed/strand configurations of the basic type developed for the National Cancer Institute (NCI) atlas of regular brain implants. Irregular target volume shapes are determined from delineation in a stack of contrast enhanced computed tomography scans. The neurosurgeon may then select up to ten directions, or entry points, of surgical approach of which the program finds the optimal one under the criterion of smallest target volume diameter. Target volume cross sections are then reconstructed in 5-mm-spaced planes perpendicular to the implantation direction defined by the entry point and the target volume center. This information is used to define a closed line in an implant cross section along which peripheral seed strands are positioned and which has now an irregular shape. Optimization points are defined opposite peripheral seeds on the target volume surface to which the treatment dose rate is prescribed. Three different optimization algorithms are available: linear least-squares programming, quadratic programming with constraints, and a simplex method. The optimization routine is implemented into a commercial treatment planning system. It generates coordinate and source strength information of the optimized seed configurations for further dose rate distribution calculation with the treatment planning system, and also the coordinate settings for the stereotaxic Brown-Roberts-Wells (BRW) implantation device

  15. Computer-assisted intraoperative visualization of dental implants. Augmented reality in medicine

    International Nuclear Information System (INIS)

    Ploder, O.; Wagner, A.; Enislidis, G.; Ewers, R.

    1995-01-01

    In this paper, a recently developed computer-based dental implant positioning system with an image-to-tissue interface is presented. On a computer monitor or in a head-up display, planned implant positions and the implant drill are graphically superimposed on the patient's anatomy. Electromagnetic 3