WorldWideScience

Sample records for implantation functional study

  1. Impact of an implantable steroid contraceptive (etonogestrel-releasing implant) on quality of life and sexual function: a preliminary study.

    Science.gov (United States)

    Di Carlo, Costantino; Sansone, Anna; De Rosa, Nicoletta; Gargano, Virginia; Tommaselli, Giovanni Antonio; Nappi, Carmine; Bifulco, Giuseppe

    2014-01-01

    The aim of the study was to determine the impact of etonogestrel (ENG)-implant used for contraceptive purpose on Quality of life (QoL) and on sexual function (FSF) of healthy Italian women. The Female Sexual Function Index (FSFI) questionnaire and the Short Form-36 (SF-36) validated questionnaire were administered at baseline, 3 and 6 months after insertion of Nexplanon. The implant seems to have a positive impact on QoL after the first three months of therapy. Users showed an improved general health status and physical role status. The implant did not show negative effects on libido and on sexual function. In the first three months of treatment, users experienced a temporary reduction of vitality, mental health, social functioning and emotional role functioning, which seem to disappear after six months of therapy.

  2. Thermal-mechanical study of functionally graded dental implants with the finite element method.

    Science.gov (United States)

    Wang, F; Lee, H P; Lu, C

    2007-01-01

    This article investigates the thermal-mechanical performance of hydroxyapatite/titanium (HA/Ti) functionally graded (FG) dental implants with the three-dimensional finite element method. The stresses induced by occlusal force for the present HA/Ti FG implant are calculated to compare with the corresponding stresses for the titanium dental implant. Thermal-mechanical effect of temperature variation due to daily oral activity is also studied. The HA/Ti FG dental implant performance is evaluated against the maximum von Mises stress, which is the general performance indicator, the first principal/tensile stress for mechanical failure of implant-bone-bond and the third principal/compressive stress for bone absorption. Simulation results indicate that under the influence of occlusal force only, the FG implants with different HA fraction along the implant length perform almost equally well, while the titanium implant sustains much higher von Mises stress. However, when thermal stress is also considered, the FG implant having HA fraction exponential index of m = 2 with temperature decrease of 20 degrees C yields the highest first principal and von Mises stresses among all the FG and titanium implants.

  3. Masticatory function and patient satisfaction with implant-supported mandibular overdentures: a prospective 5-year study

    DEFF Research Database (Denmark)

    Bakke, Merete; Holm, Betty; Gotfredsen, Klaus

    2002-01-01

    PURPOSE: The aim of this study was to assess the outcome of treatment with implant-supported mandibular overdentures in terms of biting and chewing, in entirely satisfied and not fully satisfied patients. MATERIALS AND METHODS: Twelve edentulous patients who had worn dentures for at least 5 years...... muscle activity, even before implant placement, than the entirely satisfied patients. CONCLUSION: Implant-supported mandibular overdenture treatment permits better biting and chewing function than conventional complete dentures.......PURPOSE: The aim of this study was to assess the outcome of treatment with implant-supported mandibular overdentures in terms of biting and chewing, in entirely satisfied and not fully satisfied patients. MATERIALS AND METHODS: Twelve edentulous patients who had worn dentures for at least 5 years...... participated. They were in good health but had retention problems with their mandibular dentures. First, all patients received new dentures. After 3 months, two Astra Tech implants were placed in the anterior part of the mandible, and 6 months later the abutments were connected. Patient assessment...

  4. Functional studies of signaling pathways in peri-implantation development of the mouse embryo by RNAi

    Directory of Open Access Journals (Sweden)

    Bell Graham

    2005-12-01

    Full Text Available Abstract Background Studies of gene function in the mouse have relied mainly on gene targeting via homologous recombination. However, this approach is difficult to apply in specific windows of time, and to simultaneously knock-down multiple genes. Here we report an efficient method for dsRNA-mediated gene silencing in late cleavage-stage mouse embryos that permits examination of phenotypes at post-implantation stages. Results We show that introduction of Bmp4 dsRNA into intact blastocysts by electroporation recapitulates the genetic Bmp4 null phenotype at gastrulation. It also reveals a novel role for Bmp4 in the regulation the anterior visceral endoderm specific gene expression and its positioning. We also show that RNAi can be used to simultaneously target several genes. When applied to the three murine isoforms of Dishevelled, it leads to earlier defects than previously observed in double knock-outs. These include severe delays in post-implantation development and defects in the anterior midline and neural folds at headfold stages. Conclusion Our results indicate that the BMP4 signalling pathway contributes to the development of the anterior visceral endoderm, and reveal an early functional redundancy between the products of the murine Dishevelled genes. The proposed approach constitutes a powerful tool to screen the functions of genes that govern the development of the mouse embryo.

  5. Implanted neuroprosthesis for assisting arm and hand function after stroke: a case study.

    Science.gov (United States)

    Knutson, Jayme S; Chae, John; Hart, Ronald L; Keith, Michael W; Hoyen, Harry A; Harley, Mary Y; Hisel, Terri Z; Bryden, Anne M; Kilgore, Kevin L; Peckham, Hunter

    2012-01-01

    Loss of arm and hand function is common after stroke. An implantable, 12-channel, electromyogram (EMG)-controlled functional electrical stimulation neuroprosthesis (NP) may be a viable assistive device for upper-limb hemiplegia. In this study, a research participant 4.8 yr poststroke underwent presurgical screening, surgical installation of the NP, training, and assessment of upper-limb impairment, activity limitation, and satisfaction over a 2.3 yr period. The NP increased active range of finger extension from 3 to 96 degrees, increased lateral pinch force from 16 to 29 N, increased the number of objects from 1 to 4 out of 6 that the participant could grasp and place in a Grasp-Release Test, and increased the Arm Motor Abilities Test score by 0.3 points. The upper-limb Fugl-Meyer score increased from 27 at baseline to 36 by the end of the study. The participant reported using the NP at home 3-4 d/wk, up to 3 h/d for exercise and household tasks. The effectiveness of the NP to assist with activities of daily living was dependent on the degree of flexor tone, which varied with task and level of fatigue. The EMG-based control strategy was not successfully implemented; button presses were used instead. Further advancements in technology may improve ease of use and address limitations caused by muscle spasticity.

  6. Implanted Neuroprosthesis for Assisting Arm and Hand Function after Stroke: A Case Study

    Science.gov (United States)

    Knutson, Jayme S.; Chae, John; Hart, Ronald L.; Keith, Michael W.; Hoyen, Harry A.; Harley, Mary Y.; Hisel, Terri Z.; Bryden, Anne M.; Kilgore, Kevin L.; Peckham, P. Hunter

    2012-01-01

    Loss of arm and hand function is common after stroke. An implantable 12-channel electromyogram (EMG)-controlled functional electrical stimulation neuroprosthesis (NP) may be a viable assistive device for upper limb hemiplegia. In this study, a research participant 4.8 yrs post-stroke underwent pre-surgical screening, surgical installation of the NP, training, and assessments of upper limb impairment, activity limitation, and satisfaction over a 2.3-yr period. The NP increased active range of finger extension from 3 to 96 degrees, increased lateral pinch force from 16 to 29 N, increased the number of objects from 1 to 4 out of 6 that the participant could grasp and place in a Grasp-Release Test, and increased the Arm Motor Abilities Test score by 0.3 points. The upper limb Fugl-Meyer score increased from 27 at baseline to 36 by end-of-study. The participant reported using the NP at home 3–4 days/wk, up to 3 hrs/day for exercise and household tasks. The effectiveness of the NP to assist with ADL was dependent on the degree of flexor tone, which varied with task and level of fatigue. The EMG-based control strategy was not successfully implemented; button presses were used instead. Further advancements in technology may improve ease of use and address limitations caused by muscle spasticity. PMID:23516054

  7. Efficacy Study of a Fully Implanted Neuroprosthesis for Functional Benefit to Individuals with Tetraplegia

    Science.gov (United States)

    2016-10-01

    modules (stimulators, biopotential recording) for the NNP. As a result, it may require more time to fabricate a complete set for implantation, but we...for our research subjects that is adjacent to our rehabilitation hospital and to our research laboratories . This facility essentially serves as a...this additional information and, in fact, cannot be completed without it. We will continue to report on these implantation procedures to keep the

  8. Short-term improvement of masticatory function after implant restoration

    OpenAIRE

    Kang, Si-Mook; Lee, Sang-Soo; Kwon, Ho-Keun; Kim, Baek-Il

    2015-01-01

    Purpose Dental implants present several advantages over other tooth replacement options. However, there has been little research on masticatory function in relation to implant treatment. Therefore, the aim of the present study was to evaluate the improvement of masticatory function two weeks after implant restoration. Methods Masticatory ability was evaluated with the subjective food intake ability (FIA) and objective mixing ability index (MAI) methods. Fifty-four subjects with first and seco...

  9. Design optimization of functionally graded dental implant.

    Science.gov (United States)

    Hedia, H S; Mahmoud, Nemat-Alla

    2004-01-01

    The continuous increase of man's life span, and the growing confidence in using artificial materials inside the human body necessities introducing more effective prosthesis and implant materials. However, no artificial implant has biomechanical properties equivalent to the original tissue. Recently, titanium and bioceramic materials, such as hydroxyapatite are extensively used as fabrication materials for dental implant due to their high compatibility with hard tissue and living bone. Titanium has reasonable stiffness and strength while hydroxyapatite has low stiffness, low strength and high ability to reach full integration with living bone. In order to obtain good dental implantation of the biomaterial; full integration of the implant with living bone should be satisfied. Minimum stresses in the implant and the bone must be achieved to increase the life of the implant and prevent bone resorption. Therefore, the aim of the current investigation is to design an implant made from functionally graded material (FGM) to achieve the above advantages. The finite element method and optimization technique are used to reach the required implant design. The optimal materials of the FGM dental implant are found to be hydroxyapatite/titanium. The investigations have shown that the maximum stress in the bone for the hydroxyapatite/titanium FGM implant has been reduced by about 22% and 28% compared to currently used titanium and stainless steel dental implants, respectively.

  10. Functional aspects of treatment with implant-supported single crowns: a quality control study in subjects with tooth agenesis

    DEFF Research Database (Denmark)

    Goshima, Kenichi; Lexner, Michala O; Thomsen, Carsten Eckhart

    2010-01-01

    after implant placement shortly before crown cementation, and again 1 month after cementation. It consisted of questionnaires [including Oral Health Impact Profile (OHIP-49)] and functional examination with plastic strips, the Dental Prescale Film and the Occluzer system, Xylitol color-changeable gum......BACKGROUND: No comprehensive patient-centered and clinical evaluations of the functional effect of treatment with implant-supported single crowns (ISSC) have been reported previously. OBJECTIVE: To investigate whether and how treatment with ISSC affects masticatory function and Oral Health...

  11. Chimeric Peptides as Implant Functionalization Agents for Titanium Alloy Implants with Antimicrobial Properties

    Science.gov (United States)

    Yucesoy, Deniz T.; Hnilova, Marketa; Boone, Kyle; Arnold, Paul M.; Snead, Malcolm L.; Tamerler, Candan

    2015-04-01

    Implant-associated infections can have severe effects on the longevity of implant devices and they also represent a major cause of implant failures. Treating these infections associated with implants by antibiotics is not always an effective strategy due to poor penetration rates of antibiotics into biofilms. Additionally, emerging antibiotic resistance poses serious concerns. There is an urge to develop effective antibacterial surfaces that prevent bacterial adhesion and proliferation. A novel class of bacterial therapeutic agents, known as antimicrobial peptides (AMPs), are receiving increasing attention as an unconventional option to treat septic infection, partly due to their capacity to stimulate innate immune responses and for the difficulty of microorganisms to develop resistance towards them. While host and bacterial cells compete in determining the ultimate fate of the implant, functionalization of implant surfaces with AMPs can shift the balance and prevent implant infections. In the present study, we developed a novel chimeric peptide to functionalize the implant material surface. The chimeric peptide simultaneously presents two functionalities, with one domain binding to a titanium alloy implant surface through a titanium-binding domain while the other domain displays an antimicrobial property. This approach gains strength through control over the bio-material interfaces, a property built upon molecular recognition and self-assembly through a titanium alloy binding domain in the chimeric peptide. The efficiency of chimeric peptide both in-solution and absorbed onto titanium alloy surface was evaluated in vitro against three common human host infectious bacteria, Streptococcus mutans, Staphylococcus epidermidis, and Escherichia coli. In biological interactions such as occur on implants, it is the surface and the interface that dictate the ultimate outcome. Controlling the implant surface by creating an interface composed chimeric peptides may therefore

  12. A study of functional outcomes following implantation of a total distal radioulnar joint prosthesis.

    Science.gov (United States)

    Laurentin-Pérez, L A; Goodwin, A N; Babb, B A; Scheker, L R

    2008-02-01

    This paper reports a long-term follow-up measuring pain, range of motion and weight-bearing ability, following implantation of a total distal radioulnar joint prosthesis. This prosthesis differs from excision arthroplasties and ulnar head replacements by replacing all three components of the distal radioulnar joint, viz. the sigmoid notch, the ulnar head and the triangular fibrocartilage. The design allows longitudinal migration of the radius throughout pronation and supination, as well as load bearing of the wrist. Thirty-one patients receiving the prosthesis returned or were interviewed by telephone at a mean of 5.9 (range 4-9) years. Pronation increased from a mean of 65.5 degrees (range 5-90 degrees ) to 74 degrees (range 20-90 degrees ) and supination from 53 degrees (range 5-90 degrees ) to 70 degrees (range 20-90 degrees ) while greatly diminishing and/or eliminating pain. Grip increased from a mean of 10 kg (22 lbs) to 24 kg (52 lbs). Weight bearing was restored or increased in 29 of 31 patients.

  13. Decellularized aortic conduits: could their cryopreservation affect post-implantation outcomes? A morpho-functional study on porcine homografts.

    Science.gov (United States)

    Gallo, Michele; Bonetti, Antonella; Poser, Helen; Naso, Filippo; Bottio, Tomaso; Bianco, Roberto; Paolin, Adolfo; Franci, Paolo; Busetto, Roberto; Frigo, Anna Chiara; Buratto, Edward; Spina, Michele; Marchini, Maurizio; Ortolani, Fulvia; Iop, Laura; Gerosa, Gino

    2016-11-01

    Decellularized porcine aortic valve conduits (AVCs) implanted in a Vietnamese Pig (VP) experimental animal model were matched against decellularized and then cryopreserved AVCs to assess the effect of cryopreservation on graft hemodynamic performance and propensity to in vivo repopulation by host's cells. VPs (n = 12) underwent right ventricular outflow tract substitution using AVC allografts and were studied for 15-month follow-up. VPs were randomized into two groups, receiving AVCs treated with decellularization alone (D; n = 6) or decellularization/cryopreservation (DC; n = 6), respectively. Serial echocardiography was carried out to follow up hemodynamic function. All explanted AVCs were processed for light and electron microscopy. No signs of dilatation, progressive stenosis, regurgitation, and macroscopic calcification were echocardiographically observed in both D and DC groups. Explanted D grafts exhibited near-normal features, whereas the presence of calcification, inflammatory infiltrates, and disarray of elastic lamellae occurred in some DC grafts. In the unaltered regions of AVCs from both groups, almost complete re-endothelialization was observed for both valve cusps and aorta walls. In addition, side-by-side repopulation by recipient's fibroblasts, myofibroblasts, and smooth muscle cells was paralleled by ongoing tissue remodeling, as revealed by the ultrastructural identification of typical canals of collagen fibrillogenesis and elastogenesis-related features. Incipient neo-vascularization and re-innervation of medial and adventitial tunicae of grafted aortic walls were also detected for both D and DC groups. Cryopreservation did not affect post-implantation AVC hemodynamic behavior and was topically propensive to cell repopulation and tissue renewal, although graft deterioration including calcification was present in several areas. Thus, these preliminary data provide essential information on feasibility of decellularization and

  14. Short-term improvement of masticatory function after implant restoration

    Science.gov (United States)

    2015-01-01

    Purpose Dental implants present several advantages over other tooth replacement options. However, there has been little research on masticatory function in relation to implant treatment. Therefore, the aim of the present study was to evaluate the improvement of masticatory function two weeks after implant restoration. Methods Masticatory ability was evaluated with the subjective food intake ability (FIA) and objective mixing ability index (MAI) methods. Fifty-four subjects with first and second missing molars completed the study. The subjects were asked to complete a self-reported questionnaire about 30 different food items, and to chew wax samples 10 times both before and two weeks after implant restoration. A total of 108 waxes were analyzed with an image analysis program. Results Dental implant restoration for lost molar teeth on one side increased the FIA score by 9.0% (P<0.0001). The MAI score also increased, by 14.3% after implant restoration (P<0.0001). Comparison between the good and poor mastication groups, which were subdivided based on the median MAI score before implant restoration, showed that the FIA score of the poor group was enhanced 1.1-fold while its MAI score was enhanced 2.0-fold two weeks after an implant surgery. Conclusions Using the FIA and MAI assessment methods, this study showed that masticatory function was improved two weeks after implant restoration. In particular, the enhancement of masticatory function by implant restoration was greater in patients with relatively poor initial mastication than in those with good initial mastication. PMID:26734490

  15. Importance of cochlear health for implant function.

    Science.gov (United States)

    Pfingst, Bryan E; Zhou, Ning; Colesa, Deborah J; Watts, Melissa M; Strahl, Stefan B; Garadat, Soha N; Schvartz-Leyzac, Kara C; Budenz, Cameron L; Raphael, Yehoash; Zwolan, Teresa A

    2015-04-01

    Amazing progress has been made in providing useful hearing to hearing-impaired individuals using cochlear implants, but challenges remain. One such challenge is understanding the effects of partial degeneration of the auditory nerve, the target of cochlear implant stimulation. Here we review studies from our human and animal laboratories aimed at characterizing the health of the implanted cochlea and the auditory nerve. We use the data on cochlear and neural health to guide rehabilitation strategies. The data also motivate the development of tissue-engineering procedures to preserve or build a healthy cochlea and improve performance obtained by cochlear implant recipients or eventually replace the need for a cochlear implant. This article is part of a Special Issue entitled .

  16. Bone remodeling induced by dental implants of functionally graded materials.

    Science.gov (United States)

    Lin, Daniel; Li, Qing; Li, Wei; Swain, Michael

    2010-02-01

    Functionally graded material (FGM) had been developed as a potential implant material to replace titanium for its improved capability of initial osseointegration. The idea behind FGM dental implant is that its properties can be tailored in accordance with the biomechanical needs at different regions adapting to its hosting bony tissues, therefore creating an improved overall integration and stability in the entire restoration. However, there have been very few reports available so far on predicting bone remodeling induced by FGM dental implants. This article aims to evaluate bone remodeling when replacing the titanium with a hydroxyapatite/collagen (HAP/Col) FGM model. A finite element model was constructed in the buccal-lingual section of a dental implant-bone structure generated from in vivo CT scan images. The remodeling simulation was performed over a 4 year healing period. Comparisons were made between the titanium implant and various FGM implants of this model. The FGM implants showed an improved bone remodeling outcome. The study is expected to provide a basis for future development of FGM implants.

  17. Dental implants from functionally graded materials.

    Science.gov (United States)

    Mehrali, Mehdi; Shirazi, Farid Seyed; Mehrali, Mohammad; Metselaar, Hendrik Simon Cornelis; Kadri, Nahrizul Adib Bin; Osman, Noor Azuan Abu

    2013-10-01

    Functionally graded material (FGM) is a heterogeneous composite material including a number of constituents that exhibit a compositional gradient from one surface of the material to the other subsequently, resulting in a material with continuously varying properties in the thickness direction. FGMs are gaining attention for biomedical applications, especially for implants, owing to their reported superior composition. Dental implants can be functionally graded to create an optimized mechanical behavior and achieve the intended biocompatibility and osseointegration improvement. This review presents a comprehensive summary of biomaterials and manufacturing techniques researchers employ throughout the world. Generally, FGM and FGM porous biomaterials are more difficult to fabricate than uniform or homogenous biomaterials. Therefore, our discussion is intended to give the readers about successful and obstacles fabrication of FGM and porous FGM in dental implants that will bring state-of-the-art technology to the bedside and develop quality of life and present standards of care.

  18. Electrodeposited silk coatings for functionalized implant applications

    Science.gov (United States)

    Elia, Roberto

    The mechanical and morphological properties of titanium as well as its biocompatibility and osteoinductive characteristics have made it the material of choice for dental implant systems. Although the success rate of titanium implants exceeds 90% in healthy individuals, a large subset of the population has one or more risk factors that inhibit implant integration. Treatments and coatings have been developed to improve clinical outcomes via introduction of appropriate surface topography, texture and roughness or incorporation of bioactive molecules. It is essential that the coatings and associated deposition techniques are controllable and reproducible. Currently, methods of depositing functional coatings are dictated by numerous parameters (temperature, particle size distribution, pH and voltage), which result in variable coating thickness, strength, porosity and weight, and hinder or preclude biomolecule incorporation. Silk is a highly versatile protein with a unique combination of mechanical and physical properties, including tunable degradation, biocompatibility, drug stabilizing capabilities and mechanical properties. Most recently an electrogelation technique was developed which allows for the deposition of gels which dry seamlessly over the contoured topography of the conductive substrate. In this work we examine the potential use of silk electrogels as mechanically robust implant coatings capable of sequestering and releasing therapeutic agents. Electrodeposition of silk electrogels formed in uniform electric fields was characterized with respect to field intensity and deposition time. Gel formation kinetics were used to derive functions which allowed for the prediction of coating deposition over a range of process and solution parameters. Silk electrogel growth orientation was shown to be influenced by the applied electric field. Coatings were reproducible and tunable via intrinsic silk solution properties and extrinsic process parameters. Adhesion was

  19. Masticatory function with implant-supported overdentures

    NARCIS (Netherlands)

    van Kampen, FMC; van der Bilt, A; Cune, MS; Fontijn-Tekamp, FA; Bosman, F

    2004-01-01

    The type of attachment that is used in implant-supported mandibular overdentures may influence the retention and stability of the prosthesis and, thus, masticatory function. In this within- subject cross- over clinical trial, we examined the hypothesis that greater retention and stability of the ove

  20. Evaluation of surgically retrieved temporomandibular joint alloplastic implants: pilot study.

    Science.gov (United States)

    Ferreira, Joao N A R; Ko, Ching-Chang; Myers, Sandra; Swift, James; Fricton, James R

    2008-06-01

    The purpose of this study was to perform a retrieval analysis of temporomandibular joint (TMJ) alloplastic interpositional implants and test possible correlation between implant failure features and patient clinical outcomes. In addition, we investigated the implants' surface and examined the foreign body reaction associated with different types of alloplastic materials. Twelve implants (Proplast/Teflon [Vitek, Houston, TX] and Silastic [Dow Corning, Midland, MI]) were surgically removed from the patients' TMJs. Implant surface failure features (fracture length, perforation of the implants) were observed using stereomicroscopy and recorded for description of the failure mechanisms and to statistically compare with clinical outcomes. Patients' clinical data (pain symptoms and mandibular function) were collected and examined. Clinical outcomes were obtained relative to symptom severity (Symptom Severity Index [SSI]) and jaw function (modified Mandibular Function Impairment Questionnaire [mMFIQ]). Peri-implant soft tissues and implants were analyzed with light microscopy and stereo zoom microscopy. Electron microprobe analysis of implant fragments and peri-implant tissues was performed. The statistical results showed that only the presence of implant perforation was statistically associated with the SSI, specifically with the pain tolerability dimension. No statistical association was seen between any of the other implant failure predictors and the SSI and between the predictors and the mMFIQ. Stereo zoom microscopy suggested that Proplast/Teflon implants (n = 7) were susceptible to perforation, layer tearing, fracture and fiber extrusion. The Silastic implants (n = 3) revealed a possible center perforation with fracture lines towards the periphery and fiber extrusion. Teflon implant wear debris particles appear to trigger a multinucleated giant cell foreign body reaction. Facial pain was a significant correlate to perforation and breakdown of the alloplastic TMJ

  1. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    OpenAIRE

    Stamatović Novak; Matić Smiljana; Tatić Zoran; Petković-Ćurčin Aleksandra; Vojvodić Danilo; Rakić Mia

    2013-01-01

    Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following t...

  2. Temperature-dependant study of phosphorus ion implantation in germanium

    Science.gov (United States)

    Razali, M. A.; Smith, A. J.; Jeynes, C.; Gwilliam, R. M.

    2012-11-01

    We present experimental results on shallow junction formation in germanium by phosphorus ion implantation and standard rapid thermal processing. An attempt is made to improve phosphorus activation by implanting phosphorus at high and low temperature. The focus is on studying the germanium damage and phosphorus activation as a function of implant temperature. Rutherford backscattering spectrometry with channelling and Hall Effect measurements are employed for characterisation of germanium damage and phosphorus activation, respectively. High and low temperature implants were found to be better compared to room temperature implant.

  3. Functional outcome of auditory implants in hearing loss.

    Science.gov (United States)

    Di Girolamo, S; Saccoccio, A; Giacomini, P G; Ottaviani, F

    2007-01-01

    The auditory implant provides a new mechanism for hearing when a hearing aid is not enough. It is the only medical technology able to functionally restore a human sense i.e. hearing. The auditory implant is very different from a hearing aid. Hearing aids amplify sound. Auditory implants compensate for damaged or non-working parts of the inner ear because they can directly stimulate the acoustic nerve. There are two principal types of auditory implant: the cochlear implant and the auditory brainstem implant. They have common basic characteristics, but different applications. A cochlear implant attempts to replace a function lost by the cochlea, usually due to an absence of functioning hair cells; the auditory brainstem implant (ABI) is a modification of the cochlear implant, in which the electrode array is placed directly into the brain when the acoustic nerve is not anymore able to carry the auditory signal. Different types of deaf or severely hearing-impaired patients choose auditory implants. Both children and adults can be candidates for implants. The best age for implantation is still being debated, but most children who receive implants are between 2 and 6 years old. Earlier implantation seems to perform better thanks to neural plasticity. The decision to receive an implant should involve a discussion with many medical specialists and an experienced surgeon.

  4. Study of Endometrial Receptivity during Implantation in Implantation Dysfunction Mouse

    Institute of Scientific and Technical Information of China (English)

    Yan-juan LIU; Guang-ying HUANG; Ming-wei YANG; Fu-er LU

    2008-01-01

    Objective To establish the mice model of implantation dysfunction and to study the endometrial receptivity during implantation in implantation dysfunction mouse. Methods Sexually mature female virgin, Kunming mice were randomly assigned to the control group and the model group postcoitally. The model mice at 9 : 00 AM on d 4 of pregnancy(d 4) were injected subcutaneously with mifepristone. All animals were sacrificed at 9:00 PM on d 4 and their uterine horns were examined for the presence of implanted embryos. Histopathology of uterine endometrium was observed by light-microscope. The endometrial expressions of estrogen receptor (ER) and progesterone receptor (PR) assessed by immunnohistochemical SP method. The endometrial expressions of ER mRNA and PR mRNA were assessed by semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR).Results Compared with control group, implantation rates and average embryo number significently decreased in model group, the development of endometrium was inhibited. In model group, absorbency and area rate of ER and PR in the gland and stroma were lower than those in control group (P<0.05). Expressions of ER mRNA and PR mRNA in model uterus were significantly lower than those in the control.Conclusion The endometrial receptivity and implantation decreased in mifepristoneinduced implantation dysfunction mouse.

  5. Impact of dental implant insertion method on the peri-implant bone tissue: Experimental study

    Directory of Open Access Journals (Sweden)

    Stamatović Novak

    2013-01-01

    Full Text Available Background/Aim. The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. Methods. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. Results. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 105, α = 0.05. No necrosis and osteoblastic activity were observed. Conclusion. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction and bone tissue necrosis, while better results were achieved by the two-stage method regarding the number of osteocytes.

  6. Public perceptions of dental implants: a qualitative study.

    Science.gov (United States)

    Wang, Guihua; Gao, Xiaoli; Lo, Edward C M

    2015-07-01

    Dental implants have become a popular option for treating partially dentate or edentulous patients. Information on dental implants is widely available in the public domain and is disseminated through industries and dental practitioners at various levels/disciplines. This qualitative study aimed to evaluate the public's information acquisition and their perceptions of dental implants and the effects of these on their care-seeking and decision making. A purposive sample of 28 adults were recruited to join six focus groups. To be eligible, one must be 35-64 years of age, had never been engaged in dentally related jobs, had at least one missing tooth, and had heard about dental implant but never received dental implant or entered into any dental consultation regarding dental implants. All of the focus groups discussions were transcribed verbatim and subjected to thematic content analysis following a grounded theory approach. Participants acquired information on dental implants through various means, such as patient information boards, printed advertisements, social media, and personal connections. They expected dental implants to restore the patients' appearance, functions, and quality of life to absolute normality. They regarded dental implants as a panacea for all cases of missing teeth, overestimated their functions and longevity, and underestimated the expertise needed to carry out the clinical procedures. They were deterred from seeking dental implant treatment by the high price, invasive procedures, risks, and complications. Members of the public were exposed to information of varying quality and had some unrealistic expectations regarding dental implants. Such perceptions may shape their care-seeking behaviours and decision-making processes in one way or another. The views and experiences gathered in this qualitative study could assist clinicians to better understand the public's perspectives, facilitate constructive patient-dentist communication, and contribute

  7. Novel Bio-functional Magnesium Coating on Porous Ti6Al4V Orthopaedic Implants: In vitro and In vivo Study

    Science.gov (United States)

    Li, Xiaokang; Gao, Peng; Wan, Peng; Pei, Yifeng; Shi, Lei; Fan, Bo; Shen, Chao; Xiao, Xin; Yang, Ke; Guo, Zheng

    2017-01-01

    Titanium and its alloys with various porous structures are one of the most important metals used in orthopaedic implants due to favourable properties as replacement for hard tissues. However, surface modification is critical to improve the osteointegration of titanium and its alloys. In this study, a bioactive magnesium coating was successfully fabricated on porous Ti6Al4V by means of arc ion plating, which was proved with fine grain size and high film/substrate adhesion. The surface composition and morphology were characterized by X-ray diffraction and SEM equipped with energy dispersive spectroscopy. Furthermore, the in vitro study of cytotoxicity and proliferation of MC3T3-E1 cells showed that magnesium coated porous Ti6Al4V had suitable degradation and biocompatibility. Moreover, the in vivo studies including fluorescent labelling, micro-computed tomography analysis scan and Van-Gieson staining of histological sections indicated that magnesium coated porous Ti6Al4V could significantly promote bone regeneration in rabbit femoral condylar defects after implantation for 4 and 8 weeks, and has better osteogenesis and osteointegration than the bare porous Ti6Al4V. Therefore, it is expected that this bioactive magnesium coating on porous Ti6Al4V scaffolds with improved osteointegration and osteogenesis functions can be used for orthopedic applications. PMID:28102294

  8. Histopathological Verification of Osteoimmunological Mediators in Peri-Implantitis and Correlation to Bone Loss and Implant Functional Period.

    Science.gov (United States)

    Konermann, Anna; Götz, Werner; Le, Michael; Dirk, Cornelius; Lossdörfer, Stefan; Heinemann, Friedhelm

    2016-02-01

    Peri-implantitis (PI) is characterized by inflammation and bone resorption eventually leading to implant failure, but the characteristic pathologic determinants are undefined to date. This study aims to elucidate the parameters involved in PI pathogenesis, including intraoral implant retention time, extent of bone loss, smoking history, and identification of osteoimmunological markers for inflammation and bone loss. Peri-implant tissues (n = 21) displaying clinically diagnosed PI from patients with vertical bone loss ranging from 0-12 mm and implant function period between 1 and 60 months were evaluated by histochemistry and immunohistochemistry for TRAP, CD3, RANK, RANKL, OPG, and TNF-α. Statistical analyses were performed with the Welch test and correlation coefficients were calculated. Most bone resorption occurred during the first 12 months of implant function and correlated with the extent of inflammation, although histological signs of inflammation strongly varied between samples from minimal appearance of inflammatory cells to extended infiltrates. Implant function period and smoking history did not significantly affect the degree of inflammation. Higher RANK levels emerged in the first 12 months of implant function compared to longer retention times and were negatively correlated to the occurrence of RANKL. Additionally, histological signs of inflammation were about two-fold higher in specimens with bone resorption up from 5 mm compared to under 5 mm. CD3(+) cells were more prevalent in extensive inflammatory infiltrates and samples derived from smokers. Our analyses proved that PI-induced bone loss is differentially influenced by the parameters evaluated in this study, but a distinct interconnection between disease severity and implant retention time can be established.

  9. A test of static and dynamic balance function in children with cochlear implants: the vestibular olympics.

    Science.gov (United States)

    Cushing, Sharon L; Chia, Ruth; James, Adrian L; Papsin, Blake C; Gordon, Karen A

    2008-01-01

    To determine the incidence of static and dynamic balance dysfunction in a group of children with profound sensorineural hearing loss receiving a cochlear implant and to assess the impact of cochlear implant activation on equilibrium. Observational cross-sectional study of children with single-sided implants, tested under 2 conditions: (1) implant on and (2) implant off in a random order. Ambulatory setting within an academic, tertiary care children's hospital. Forty-one children (ages 4-17 years) with cochlear implants comprised the study group. Fourteen children with normal hearing served as controls. All participants performed a standardized test of static and dynamic balance function (Bruininks-Oseretsky Test of Motor Proficiency 2 [BOT2], balance subset). Children with implants performed the BOT2 under the 2 randomized conditions. Overall performance on the balance subset of the BOT2 and the influence of implant activation on performance. The mean (SD) age-adjusted scale score for our control group was 17 (5) points (95% confidence interval [CI], 14-20), which was not significantly different (P = .15) from the published age-adjusted mean for the BOT2 balance subset (15 [5] points). The group that had undergone implantation, however, performed significantly more poorly (12 [ 6] points; 95% CI, 10-14) than either the control group or the published test mean (P = .004). Children with implants performed better with their implants on than with their implants off (mean [SD] difference, 1.3 [2.7] points; 95% CI, 0.3-2.3; P = .01). Large differences exist in the balance ability of children with sensorineural hearing loss requiring cochlear implantation compared with age-matched controls. Implant activation, however, conferred a slight advantage in accomplishing balance-related tasks. These results substantiate the need to further quantify the baseline vestibular dysfunction of our study population of children with cochlear implants, as well as the impact of implant

  10. Osseointegrated implants and auricular defects: a case series study.

    Science.gov (United States)

    Wright, Robert F; Zemnick, Candice; Wazen, Jack J; Asher, Eric

    2008-08-01

    The objective of this study was to report on the survival rate of 16 patients treated with extraoral implants in the auricular region, analyze treatment outcomes, and discuss important clinical variables encountered during treatment. Sixteen patients who received extraoral dental implants to retain auricular prostheses between 1987 and 2003 were followed retrospectively. The variables recorded were gender, initial diagnosis, number and size of implants, implant placement date, age at implant placement, history of radiation to the treated field, abutment size, design of initial prosthesis, age of initial prosthesis (when a remake was indicated), date of prosthesis delivery, soft tissue response, grafting procedure, date of last follow-up, and complications. All patients were thoroughly evaluated presurgically by the reconstruction team, which consisted of prosthodontists, a facial prosthetist, and an otolaryngologist. Surgical templates were used for all patients. The criteria for success of the prostheses included marginal accuracy, overall stability and function, symmetry/position, texture, color stability, and patient acceptance. Thirty-nine implants were placed in 16 patients. All 16 patients were completely satisfied with their reconstructions. No surgical complications, implant failures, or prosthetic failures were encountered. Therefore, the survival rate was 100%. Three patients (18.75%) had grade 0, seven (43.75%) had grade 1, five (31.25%) had grade 2, and one (6.25%) had grade 3 soft tissue inflammation. The inflammation completely resolved in 7 of the 13 patients (54%) with hygiene reinforcement or soft tissue reduction. The survival rate for bone-anchored titanium implants and prostheses was 100%. Bone-anchored titanium implants provided the 16 patients in this study with a safe, reliable, adhesive-free method to anchor auricular prostheses with recovery of normal appearance. Under the guidance of an appropriate implant team, proper positioning of

  11. Functional recovery of patients with ischemic cardiomyopathy treated with coronary artery bypass surgery and concomitant intramyocardial bone marrow mononuclear cell implantation: A long term follow-up study

    Directory of Open Access Journals (Sweden)

    Trifunović Zoran

    2015-01-01

    Full Text Available Background/Aim. Intramyocardial bone marrow mononuclear cells (BMMNC implantation concomitant to coronary artery bypass grafting (CABG surgery as an option for regenerative therapy in chronic ischemic heart failure was tested in a very few number of studies, with not consistent conclusions regarding improvement in left ventricular function, and with a follow-up period between 6 months and 1 year. This study was focused on testing of the hypothesis that intramyocardial BMMNC implantation, concomitant to CABG surgery in ischemic cardiomyopathy patients, leads to better postoperative long-term results regarding the primary endpoint of conditional status-functional capacity and the secondary endpoint of mortality than CABG surgery alone in a median follow-up period of 5 years. Methods. A total of 30 patients with ischemic cardiomyopathy and the median left ventricular ejection fraction (LVEF of 35.9 ± 4.7% were prospectively and randomly enrolled in a single center interventional, open labeled clinical trial as two groups: group I of 15 patients designated as the study group to receive CABG surgery and intramyocardial implantation of BMMNC and group II of 15 patients as the control group to receive only the CABG procedure. All the patients in both groups received the average of 3.4 ± 0.7 implanted coronary grafts, and all of them received the left internal mammary artery (LIMA to the left anterior descending (LAD and autovenous to other coronaries. Results. The group with BMMNC and CABG had the average of 17.5 ± 3.8 injections of BMMNC suspension with the average number of injected bone marrow mononuclear cells of 70.7 ± 32.4 × 106 in the total average volume of 5.7 ± 1.5 mL. In this volume the average count of CD34+ and CD133+ cells was 3.96 ± 2.77 × 106 and 2.65 ± 1.71 × 106, respectively. All the patients were followed up in 2.5 to 7.5 years (median, 5 years. At the end of the follow-up period, significantly more patients from the group

  12. Microscopic view of osseointegration and functional mechanisms of implant surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Han, Guang; Shen, Zhijian, E-mail: shen@mmk.su.se

    2015-11-01

    Argon ion beam polishing technique was applied to prepare the cross sections of implants feasible for high resolution scanning electron microscope investigation. The interfacial microstructure between newly formed bone and implants with three modified surfaces retrieved after in vivo test using three different animal models was characterized. By this approach it has become possible to directly observe early bone formation, the increase of bone density, and the evolution of bone structure. The two bone growth mechanisms, distant osteogenesis and contact osteogenesis, can also be distinguished. These direct observations give, at microscopic level, a better view of osseointegration and expound the functional mechanisms of various implant surfaces for osseointegration. - Highlights: • Argon ion beam polishing was used for cross sections of interface. • The interfaces between new bone and implants can be distinguished. • Two bone growth mechanisms were verified. • The functional mechanisms of three modified implants were expounded.

  13. Dental Implants - Perceiving Patients' Satisfaction in Relation to Clinical and Electromyography Study on Implant Patients.

    Directory of Open Access Journals (Sweden)

    Mohammad Khursheed Alam

    Full Text Available The aim of this study is to evaluate the satisfaction of patients with posterior implants in relation to the clinical success criteria and surface electromyography (sEMG findings of the masseter and temporalis muscles. Total 42 subjects were investigated. Twenty one subjects with posterior dental implants were interviewed using a questionnaire and the clinical success criteria were determined based on The International Congress of Oral Implantologists. The myofunction of the masticatory muscles were assessed using sEMG (21 subjects and compared to the control group of subjects without implants (21 subjects. Out of 21 subjects, all were satisfied with the aesthetics of their implant. Twenty of them (95.2% were satisfied with its function and stability. As for clinical criteria, 100% (50 of the implants were successful with no pain, mobility or exudates. sEMG findings showed that patients have significantly lower (p<0.01 basal or resting median power frequency but with muscle burst. During chewing, control subjects showed faster chewing action. There was no difference in reaction and recovery time of clenching for both groups. In conclusion, the satisfaction of implant patients was high, and which was in relation to the successful clinical success criteria and sEMG findings.

  14. Surface Functionalization of Orthopedic Titanium Implants with Bone Sialoprotein.

    Directory of Open Access Journals (Sweden)

    Andreas Baranowski

    Full Text Available Orthopedic implant failure due to aseptic loosening and mechanical instability remains a major problem in total joint replacement. Improving osseointegration at the bone-implant interface may reduce micromotion and loosening. Bone sialoprotein (BSP has been shown to enhance bone formation when coated onto titanium femoral implants and in rat calvarial defect models. However, the most appropriate method of BSP coating, the necessary level of BSP coating, and the effect of BSP coating on cell behavior remain largely unknown. In this study, BSP was covalently coupled to titanium surfaces via an aminosilane linker (APTES, and its properties were compared to BSP applied to titanium via physisorption and untreated titanium. Cell functions were examined using primary human osteoblasts (hOBs and L929 mouse fibroblasts. Gene expression of specific bone turnover markers at the RNA level was detected at different intervals. Cell adhesion to titanium surfaces treated with BSP via physisorption was not significantly different from that of untreated titanium at any time point, whereas BSP application via covalent coupling caused reduced cell adhesion during the first few hours in culture. Cell migration was increased on titanium disks that were treated with higher concentrations of BSP solution, independent of the coating method. During the early phases of hOB proliferation, a suppressive effect of BSP was observed independent of its concentration, particularly when BSP was applied to the titanium surface via physisorption. Although alkaline phosphatase activity was reduced in the BSP-coated titanium groups after 4 days in culture, increased calcium deposition was observed after 21 days. In particular, the gene expression level of RUNX2 was upregulated by BSP. The increase in calcium deposition and the stimulation of cell differentiation induced by BSP highlight its potential as a surface modifier that could enhance the osseointegration of orthopedic implants

  15. CO2 laser surface treatment of failed dental implants for re-implantation: an animal study.

    Science.gov (United States)

    Kasraei, Shahin; Torkzaban, Parviz; Shams, Bahar; Hosseinipanah, Seyed Mohammad; Farhadian, Maryam

    2016-07-01

    The aim of the present study was to evaluate the success rate of failed implants re-implanted after surface treatment with CO2 laser. Despite the widespread use of dental implants, there are many incidents of failures. It is believed that lasers can be applied to decontaminate the implant surface without damaging the implant. Ten dental implants that had failed for various reasons other than fracture or surface abrasion were subjected to CO2 laser surface treatment and randomly placed in the maxillae of dogs. Three failed implants were also placed as the negative controls after irrigation with saline solution without laser surface treatment. The stability of the implants was evaluated by the use of the Periotest values (PTVs) on the first day after surgery and at 1, 3, and 6 months post-operatively. The mean PTVs of treated implants increased at the first month interval, indicating a decrease in implant stability due to inflammation followed by healing of the tissue. At 3 and 6 months, the mean PTVs decreased compared to the 1-month interval (P implant stability. The mean PTVs increased in the negative control group compared to baseline (P implants were significantly lower than control group at 3 and 6 months after implant placement (P implantation of failed implants in Jack Russell Terrier dogs after CO2 laser surface debridement is associated with a high success rate in terms of implant stability.

  16. Perceptually optimized gain function for cochlear implant signal-to-noise ratio based noise reduction.

    Science.gov (United States)

    Mauger, Stefan J; Dawson, Pam W; Hersbach, Adam A

    2012-01-01

    Noise reduction in cochlear implants has achieved significant speech perception improvements through spectral subtraction and signal-to-noise ratio based noise reduction techniques. Current methods use gain functions derived through mathematical optimization or motivated by normal listening psychoacoustic experiments. Although these gain functions have been able to improve speech perception, recent studies have indicated that they are not optimal for cochlear implant noise reduction. This study systematically investigates cochlear implant recipients' speech perception and listening preference of noise reduction with a range of gain functions. Results suggest an advantageous gain function and show that gain functions currently used for noise reduction are not optimal for cochlear implant recipients. Using the cochlear implant optimised gain function, a 27% improvement over the current advanced combination encoder (ACE) stimulation strategy in speech weighted noise and a 7% improvement over current noise reduction strategies were observed in babble noise conditions. The optimized gain function was also most preferred by cochlear implant recipients. The CI specific gain function derived from this study can be easily incorporated into existing noise reduction strategies, to further improve listening performance for CI recipients in challenging environments.

  17. Moessbauer Studies of Implanted Impurities in Solids

    CERN Multimedia

    2002-01-01

    Moessbauer studies were performed on implanted radioactive impurities in semiconductors and metals. Radioactive isotopes (from the ISOLDE facility) decaying to a Moessbauer isotope were utilized to investigate electronic and vibrational properties of impurities and impurity-defect structures. This information is inferred from the measured impurity hyperfine interactions and Debye-Waller factor. In semiconductors isoelectronic, shallow and deep level impurities have been implanted. Complex impurity defects have been produced by the implantation process (correlated damage) or by recoil effects from the nuclear decay in both semiconductors and metals. Annealing mechanisms of the defects have been studied. \\\\ \\\\ In silicon amorphised implanted layers have been recrystallized epitaxially by rapid-thermal-annealing techniques yielding highly supersaturated, electrically-active donor concentrations. Their dissolution and migration mechanisms have been investigated in detail. The electronic configuration of Sb donors...

  18. Immediate implant loading with fixed dental restorations: An animal model study

    Directory of Open Access Journals (Sweden)

    Špadijer-Gostović Aleksandra

    2012-01-01

    Full Text Available Background/Aim. Immediate loading is considered to be the most innovative technique in contemporary implant dentistry. Recent clinical and experimental findings have demonstrated that only implants with high primary stability can be subjected to immediate loading protocol with predictable results. It is generally accepted that the most important prerequsite for successful osseointegration is achievement and maintenance of implant stability. The aim of this in vivo study was to investigate the possibility for successful application of immediate loading protocol in implant systems with different surface properties. Methods. In the experimental study 2 mongrel dogs were edentulated bilaterally in the mandibular and maxillary premolar areas. After 3 months implants were placed in a pattern 4 different commercially available implants per quadrant (n = 32: Mk III TiUnite (Nobel Biocare, Sweden, ITI TPS (Straumann, Switzerland, 3IOsseotite (Implant Innovation, USA and XiVE Cell-Plus (Friadent, Germany. Implants were subjected to immediate loading with 4 unit gold cast bridges, 2 days post implantation. The assessment of implant stability and immediate loading possibilities were done by performing Resonance frequency analysis (RFA. Results. After a 6- month loading period all bridges were in function and all implants occurred well osseointegrated. When summarizing the Implant Stability Quotient (ISQ values, it was noted that resonance frequency was significantly higher for mandibular implants. The results of this experimental setting showed that all evaluated surfaces achieved good implant stability. Increase of ISQ values was found for all implants in the mandible and partially decrease of ISQ values for maxillary implants after 6 months of functional loading with 4 unit bridges. Conclusions. Investigated endooseal implants did not show different degree of osseointegration, because there was not statisticaly significant difference among observed

  19. Immediately loaded mini dental implants as overdenture retainers: 1-Year cohort study of implant stability and peri-implant marginal bone level.

    Science.gov (United States)

    Šćepanović, Miodrag; Todorović, Aleksandar; Marković, Aleksa; Patrnogić, Vesna; Miličić, Biljana; Moufti, Adel M; Mišić, Tijana

    2015-05-01

    This 1-year cohort study investigated stability and peri-implant marginal bone level of immediately loaded mini dental implants used to retain overdentures. Each of 30 edentulous patients received 4 mini dental implants (1.8 mm × 13 mm) in the interforaminal mandibular region. The implants were immediately loaded with pre-made overdentures. Outcome measures included implant stability and bone resorption. Implant stability was measured using the Periotest Classic(®) device immediately after placement and on the 3rd and 6th weeks and the 4th, 6th and 12th months postoperatively. The peri-implant marginal bone level (PIBL) was evaluated at the implant's mesial and distal sides from the polished platform to the marginal crest. Radiographs were taken using a tailored film holder to reproducibly position the X-ray tube at the 6th week, 4th and 12th months postoperatively. The primary stability (Periotest value, PTV) measured -0.27 ± 3.41 on a scale of -8 to + 50 (lower PTV reflects higher stability). The secondary stability decreased significantly until week 6 (mean PTV = 7.61 ± 7.05) then increased significantly reaching (PTV = 6.17 ± 6.15) at 12 months. The mean PIBL measured -0.40 mm after 1 year of functional loading, with no statistically significant differences at the various follow-ups (p = 0.218). Mini dental implants placed into the interforaminal region could achieve a favorable primary stability for immediate loading. The follow-up Periotest values fluctuated, apparently reflecting the dynamics of bone remodeling, with the implants remaining clinically stable (98.3%) after 1 year of function. The 1-year bone resorption around immediately loaded MDIs is within the clinically acceptable range for standard implants. Copyright © 2014 Elsevier GmbH. All rights reserved.

  20. Design of functionally graded dental implant in the presence of cancellous bone.

    Science.gov (United States)

    Hedia, H S

    2005-10-01

    In a previous work by the author [Hedia HS, Mahmoud NA. Biomed Mater Eng 2004;14(2):133--143], a functionally graded material (FGM) dental implant was designed without cancellous bone in the model. In this investigation, the effect of the presence of cancellous bone as a thin layer around the dental implant was investigated. It is well known that the main inorganic component of natural bone is hydroxyapatite (HAP) and that the main organic component is collagen (Col). HAP implants are not bioabsorbable, and because induction of bone into and around the artificially made HAP is not always satisfactory, loosening or breakage of HAP implants might occur after implantation in the clinical application. The development of a new material that is bioabsorbable and that has osteo-conductive activity is needed. Therefore, the aim of the current investigation was to design an implant, in the presence of cancellous bone as a thin layer around it, from FGM. In this study, a novel biomaterial, Col/HAP, as a FGM, was developed using the finite element and optimization techniques that are available in the ANSYS package. These materials have a self-organized character similar to that of natural bone. The investigations have shown that the maximum stress in the cortical bone and cancellous bone for the Col/HAP functionally graded implant has been reduced by about 40% and 19%, respectively, compared with currently used titanium dental implants.

  1. Molecular Approaches to Functionalization of Dental Implant Surfaces

    Directory of Open Access Journals (Sweden)

    Angelina O. Zekiy

    2015-12-01

    Full Text Available The present review examines several approaches to improve properties of dental implants by modifying their bioactive surfaces (functionalization using the techniques of molecular transplantation. The first group of functional ligands is designed to enhance osseointegration of implants, it includes growth factors, promoting the formation and bone remodeling: bone morphogenetic proteins (BMPs, platelet-derived growth factor (PDGF, fibroblast growth factor (FGF and their combinations with each other, and several other ones. The second group of bioactive molecules does not directly stimulate bone formation, but it promotes osteoblast seeding on the implant surface due to the adhesive properties, thus accelerating osseointegration. Finally, the third group of substances used to increase the antibacterial properties of coatings, thereby reducing the formation of bacterial film on the implant surface and the risk of inflammatory rejection of the implant. Key issues of using biofunctional coatings, despite their obvious promise today still are relatively high cost, difficulties of controlling properties and its storage between the fabrication and installation of implants in the bone of the recipient.

  2. Investigation of Pathogenic Genes in Peri-Implantitis from Implant Clustering Failure Patients: A Whole-Exome Sequencing Pilot Study

    Science.gov (United States)

    Lee, Soohyung; Kim, Ji-Young; Hwang, Jihye; Kim, Sanguk; Lee, Jae-Hoon; Han, Dong-Hoo

    2014-01-01

    Peri-implantitis is a frequently occurring gum disease linked to multi-factorial traits with various environmental and genetic causalities and no known concrete pathogenesis. The varying severity of peri-implantitis among patients with relatively similar environments suggests a genetic aspect which needs to be investigated to understand and regulate the pathogenesis of the disease. Six unrelated individuals with multiple clusterization implant failure due to severe peri-implantitis were chosen for this study. These six individuals had relatively healthy lifestyles, with minimal environmental causalities affecting peri-implantitis. Research was undertaken to investigate pathogenic genes in peri-implantitis albeit with a small number of subjects and incomplete elimination of environmental causalities. Whole-exome sequencing was performed on collected saliva samples via self DNA collection kit. Common variants with minor allele frequencies (MAF) > = 0.05 from all control datasets were eliminated and variants having high and moderate impact and loss of function were used for comparison. Gene set enrichment analysis was performed to reveal functional groups associated with the genetic variants. 2,022 genes were left after filtering against dbSNP, the 1000 Genomes East Asian population, and healthy Korean randomized subsample data (GSK project). 175 (p-value implant failure. This result may demonstrate the feasibility of and provide pilot data for a larger research project aimed at discovering biomarkers for early diagnosis of peri-implantitis. PMID:24921256

  3. Effect of cancellous bone on the functionally graded dental implant concept.

    Science.gov (United States)

    Hedia, H S

    2005-01-01

    In a previous work by the author [H.S. Hedia and M. Nemat-Alla, Design optimization of functionally graded dental implant, submitted to be published in the J. Bio-Medical Materials and Engineering], a functionally graded material dental implant was designed without cansellous bone in the model. In this investigation the effect of presence cancellous bone as a thin layer around the dental implant was investigated. It is well known that the main inorganic component of natural bone is hydroxyapatite (HAP) and that the main organic component is collagen (Col). Hydroxyapatite HAP implants are not bioabsorbable, and because induction of bone into and around the artificially made HAP is not always satisfactory, loosening or breakage of HAP implants may occur after implantation in the clinical application. The development of a new material which is bioabsorbable and which has osteoconductive activity is needed. Therefore, the aim of the current investigation is to design an implant, in the presence of cancellous bone as a thin layer around it, from functionally graded material. In this study, a novel biomaterial, collagen/hydroxyapatite (Col/HAP) as a functionally graded material (FGM), was developed using the finite element and optimization techniques which are available in the ANSYS package. These materials have a self-organized character similar to that of natural bone. The investigations have shown that the maximum stress in the cortical bone and cancellous bone for the Col/HAP functionally graded implant has been reduced by about 40% and 19% respectively compared to currently used titanium dental implants.

  4. Immediate implant placement following a modified trephine/osteotome approach: success rates of 116 implants to 4 years in function.

    Science.gov (United States)

    Fugazzotto, Paul A

    2002-01-01

    A technique is presented which utilizes a trephine with a 3.0-mm external diameter followed by an osteotome to implode a core of maxillary posterior alveolar bone prior to immediate implant placement. The technique and its indications and contraindications are described in detail. One hundred sixteen implants were placed and uncovered utilizing this technique. Two implants were mobile at the time of uncovering. One hundred fourteen implants were restored and have been functioning successfully for up to 4 years according to the Albrektsson criteria, yielding a success rate of 98.3%. No implants have been lost or are failing in function.

  5. A prospective study of Astra single tooth implants.

    Science.gov (United States)

    Palmer, R M; Smith, B J; Palmer, P J; Floyd, P D

    1997-06-01

    A new design of single tooth implant (AstraTech, Molndal Sweden) featuring a microthreaded conical neck and TiO blast surface was evaluated clinically and radiographically after 2 years in function. Fifteen patients (age range 16 to 48) with missing maxillary anterior teeth (6 central incisors, 8 laterals, 1 bicuspid) had 4, 13 mm and 11, 15 mm implants placed under local anaesthesia and left for a period of 6 months before exposure and abutment connection/crown fabrication. All patients were seen at 4 to 6 monthly intervals for hygienist maintenance. Radiographs using Rinn holders and a long cone technique were taken at the crown insertion and after 1 year (14 subjects) and 2 years (12 subjects). All implants were successfully integrated at stage 2, and no implants have been lost. The internal conical seal design of the abutment/implant interface facilitated connection and there were no cases of abutment screw loosening. No soft tissue problems were observed, and the gingival morphology/health was well maintained. One crown was recemented after 18 months in function, and 1 crown was replaced because of a fracture to the porcelain incisal edge. At crown insertion, the mean bone level was 0.46 to 0.48 mm apical to the top of the implant and there were no statistically significant changes in the bone level over the 2 years of the study. In conclusion, the single tooth Astra implants were highly successful and bone changes within the first 2 years of function were comparable with other systems reporting high long-term success rates.

  6. Patient-Specific Simulation of Implant Placement and Function for Cochlear Implantation Surgery Planning

    DEFF Research Database (Denmark)

    Ceresa, Mario; Mangado Lopez, Nerea; Dejea Velardo, Hector;

    2014-01-01

    We present a framework for patient specific electrical stimulation of the cochlea, that allows to perform in-silico analysis of implant placement and function before surgery. A Statistical Shape Model (SSM) is created from high-resolution human μCT data to capture important anatomical details...

  7. Adding functionality with additive manufacturing: Fabrication of titanium-based antibiotic eluting implants.

    Science.gov (United States)

    Cox, Sophie C; Jamshidi, Parastoo; Eisenstein, Neil M; Webber, Mark A; Hassanin, Hany; Attallah, Moataz M; Shepherd, Duncan E T; Addison, Owen; Grover, Liam M

    2016-07-01

    Additive manufacturing technologies have been utilised in healthcare to create patient-specific implants. This study demonstrates the potential to add new implant functionality by further exploiting the design flexibility of these technologies. Selective laser melting was used to manufacture titanium-based (Ti-6Al-4V) implants containing a reservoir. Pore channels, connecting the implant surface to the reservoir, were incorporated to facilitate antibiotic delivery. An injectable brushite, calcium phosphate cement, was formulated as a carrier vehicle for gentamicin. Incorporation of the antibiotic significantly (p=0.01) improved the compressive strength (5.8±0.7MPa) of the cement compared to non-antibiotic samples. The controlled release of gentamicin sulphate from the calcium phosphate cement injected into the implant reservoir was demonstrated in short term elution studies using ultraviolet-visible spectroscopy. Orientation of the implant pore channels were shown, using micro-computed tomography, to impact design reproducibility and the back-pressure generated during cement injection which ultimately altered porosity. The amount of antibiotic released from all implant designs over a 6hour period (additively manufacture a titanium-based antibiotic eluting implant, which is an attractive alternative to current treatment strategies of periprosthetic infections.

  8. 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

  9. Complex dielectric function of ion implantation amorphized SiC determined by spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Lohner, T.; Zolnai, Z.; Petrik, P.; Battistig, G.; Koos, A.; Osvath, Z.; Fried, M. [Research Institute for Technical Physics and Materials Science, Konkoly Thege Miklos ut 29-33, 1121 Budapest (Hungary); Garcia Lopez, J.; Morilla, Y. [Centro Nacional de Aceleradores, Av. Thomas A. Edison 7, 41092 Sevilla (Spain)

    2008-05-15

    Measuring with a spectroscopic ellipsometer we determined the complex dielectric function of completely amorphous silicon carbide prepared by ion implantation. 860 keV Ni{sup +} ions were implanted into single crystalline 4H-SiC to produce thick amorphized layer. Ion beam analysis was applied to assess total amorphization. For this purpose {sup 4}He{sup +} ion beam of 3.5 MeV was selected taking the advantage that the scattering cross section of carbon at this energy at 165 detection angle is about six times larger than the Rutherford type. Atomic force microscopy was performed to characterize the roughness of the ion-implanted surfaces. Multiple energy Ar{sup +} implantation was used to produce homogeneous amorphous layer. The Tauc-Lorentz model was applied for the evaluation of the ellipsometric results. The implantation-induced swelling was obtained through the measurement of the step height across the masked and implanted areas. Comparison was made among the complex dielectric functions of amorphized SiC studied by us and by different research groups. It is found that the complex dielectric functions of amorphized SiC differ considerably if different ion implantation conditions were applied. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Influence of bone density on implant stability parameters and implant success: a retrospective clinical study

    Directory of Open Access Journals (Sweden)

    McGlumphy Edwin A

    2008-11-01

    Full Text Available Abstract Background The aim of the present clinical study was to determine the local bone density in dental implant recipient sites using computerized tomography (CT and to investigate the influence of local bone density on implant stability parameters and implant success. Methods A total of 300 implants were placed in 111 patients between 2003 and 2005. The bone density in each implant recipient site was determined using CT. Insertion torque and resonance frequency analysis were used as implant stability parameters. The peak insertion torque values were recorded with OsseoCare machine. The resonance frequency analysis measurements were performed with Osstell instrument immediately after implant placement, 6, and 12 months later. Results Of 300 implants placed, 20 were lost, meaning a survival rate of %. 93.3 after three years (average 3.7 ± 0.7 years. The mean bone density, insertion torque and RFA recordings of all 300 implants were 620 ± 251 HU, 36.1 ± 8 Ncm, and 65.7 ± 9 ISQ at implant placement respectively; which indicated statistically significant correlations between bone density and insertion torque values (p Conclusion CT is a useful tool to determine the bone density in the implant recipient sites, and the local bone density has a prevailing influence on primary implant stability, which is an important determinant for implant success.

  11. Impact of crestal and subcrestal implant placement in peri-implant bone: A prospective comparative study.

    Science.gov (United States)

    Pellicer-Chover, Hilario; Peñarrocha-Diago, María; Peñarrocha-Oltra, David; Gomar-Vercher, Sonia; Agustín-Panadero, Rubén; Peñarrocha-Diago, Miguel

    2016-01-01

    To assess the influence of the crestal or subcrestal placement of implants upon peri-implant bone loss over 12 months of follow-up. Twenty-six patients with a single hopeless tooth were recruited in the Oral Surgery Unit (Valencia University, Valencia, Spain). The patients were randomized into two treatment groups: group A (implants placed at crestal level) or group B (implants placed at subcrestal level). Control visits were conducted by a trained clinician at the time of implant placement and 12 months after loading. A previously established standard protocol was used to compile general data on all patients (sex and age, implant length and diameter, and brushing frequency). Implant success rate, peri-implant bone loss and the treatment of the exposed implant surface were studied. The level of statistical significance was defined as 5% (α=0.05). Twenty-three patients (8 males and 15 females, mean age 49.8±11.6 years, range 28-75 years) were included in the final data analyses, while three were excluded. All the included subjects were non-smokers with a brushing frequency of up to twice a day in 85.7% of the cases. The 23 implants comprised 10 crestal implants and 13 subcrestal implants. After implant placement, the mean bone position with respect to the implant platform in group A was 0.0 mm versus 2.16±0.88 mm in group B. After 12 months of follow-up, the mean bone positions were -0.06±1.11 mm and 0.95±1.50 mm, respectively - this representing a bone loss of 0.06±1.11 mm in the case of the crestal implants and of 1.22±1.06 mm in the case of the subcrestal implants (p=0.014). Four crestal implants and 5 subcrestal implants presented peri-implant bone levels below the platform, leaving a mean exposed treated surface of 1.13 mm and 0.57 mm, respectively. The implant osseointegration success rate at 12 months was 100% in both groups. Within the limitations of this study, bone loss was found to be greater in the case of the subcrestal implants, though from the

  12. [Mechanical studies of lumbar interbody fusion implants].

    Science.gov (United States)

    Bader, R J; Steinhauser, E; Rechl, H; Mittelmeier, W; Bertagnoli, R; Gradinger, R

    2002-05-01

    In addition to autogenous or allogeneic bone grafts, fusion cages composed of metal or plastic are being used increasingly as spacers for interbody fusion of spinal segments. The goal of this study was the mechanical testing of carbon fiber reinforced plastic (CFRP) fusion cages used for anterior lumbar interbody fusion. With a special testing device according to American Society for Testing and Materials (ASTM) standards, the mechanical properties of the implants were determined under four different loading conditions. The implants (UNION cages, Medtronic Sofamor Danek) provide sufficient axial compression, shear, and torsional strength of the implant body. Ultimate axial compression load of the fins is less than the physiological compression loads at the lumbar spine. Therefore by means of an appropriate surgical technique parallel grooves have to be reamed into the endplates of the vertebral bodies according to the fin geometry. Thereby axial compression forces affect the implants body and the fins are protected from damaging loading. Using a supplementary anterior or posterior instrumentation, in vivo failure of the fins as a result of physiological shear and torsional spinal loads is unlikely. Due to specific complications related to autogenous or allogeneic bone grafts, fusion cages made of metal or carbon fiber reinforced plastic are an important alternative implant in interbody fusion.

  13. Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function

    Directory of Open Access Journals (Sweden)

    Francesco Mangano

    2017-01-01

    Full Text Available Background. Direct metal laser sintering (DMLS is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term. Purpose. To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading. Methods. Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC% was calculated. Results. Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%. Conclusions. The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface.

  14. Histological Evidence of the Osseointegration of Fractured Direct Metal Laser Sintering Implants Retrieved after 5 Years of Function.

    Science.gov (United States)

    Mangano, Francesco; Mangano, Carlo; Piattelli, Adriano; Iezzi, Giovanna

    2017-01-01

    Direct metal laser sintering (DMLS) is an additive manufacturing technique that allows the fabrication of dental implants layer by layer through the laser fusion of titanium microparticles. The surface of DMLS implants is characterized by a high open porosity with interconnected pores of different sizes; therefore, it has the potential to enhance and accelerate bone healing. To date, however, there are no histologic/histomorphometric studies in the literature evaluating the interface between bone and DMLS implants in the long-term. To evaluate the interface between bone and DMLS implants retrieved after 5 years of functional loading. Two fractured DMLS implants were retrieved from the human jaws, using a 5 mm trephine bur. Both the implants were clinically stable and functioned regularly before fracture. The specimens were processed for histologic/histomorphometric evaluation; the bone-to-implant contact (BIC%) was calculated. Compact, mature lamellar bone was found over most of the DMLS implants in close contact with the implant surface; the histomorphometric evaluation showed a mean BIC% of 66.1% (±4.5%). The present histologic/histomorphometric study showed that DMLS implants were well integrated in bone, after 5 years of loading, with the peri-implant bone undergoing continuous remodeling at the interface.

  15. Comparative study on the osseointegration of implants in dog mandibles according to the implant surface treatment

    Science.gov (United States)

    2016-01-01

    Objectives This study compared the impact of implant surface treatment on the stability and osseointegration of implants in dog mandibles. Materials and Methods Six adult dogs received a total of 48 implants that were prepared using four different surface treatments; resorbable blast media (RBM), hydroxyapatite (HA), hydrothermal-treated HA, and sand blasting and acid etching (SLA). Implants were installed, and dogs were separated into 2- and 4-week groups. Implant stability was evaluated via Periotest M, Osstell Mentor, and removal torque analyzers. A histomorphometric analysis was also performed. Results The stability evaluation showed that all groups generally had satisfactory values. The histomorphometric evaluation via a light microscope revealed that the HA surface implant group had the highest ratio of new bone formation on the entire fixture. The hydrothermal-treated HA surface implant group showed a high ratio of bone-to-implant contact in the upper half of the implant area. Conclusion The hydrothermal-treated HA implant improved the bone-to-implant contact ratio on the upper fixture, which increased the implant stability. PMID:28053904

  16. Immediate loading of immediate mandibular implants with a full-arch fixed prosthesis: a preliminary study.

    Science.gov (United States)

    Peñarrocha, Miguel; Boronat, Araceli; Garcia, Berta

    2009-06-01

    To determine the survival of immediate dental implants with immediate loading in the partially edentulous mandible, by use of a full-arch screw-retained provisional restoration. Patients who were partially edentulous in the mandible with indications for extraction of the remaining teeth and with a minimum follow-up of 12 months after implant placement were included in the study. They were treated in chronologic order by the insertion of 6 Defcon dental implants (Impladent, Sentmenat, Spain) subjected to immediate loading (4 interforaminal and 2 posterior placements). Implants with a minimum primary stability of 60 implant stability quotient were loaded. All resin screw-retained prostheses were inserted and loaded with fully functional occlusion within 24 hours of implant placement. Eleven patients were treated with immediate implants, although 2 patients were excluded from the study for having an implant stability quotient value below 60 in at least one of the implants after surgery and did not undergo restoration with immediate loading. Fifty-four implants were placed in 9 partially edentulous patients with immediate loading with a full-arch screw-fixed prosthesis. The patients wore this provisional prosthesis during the healing period (2 months) without complication and with a high level of comfort. The survival rate of the implants was 100% at 12 months of follow-up. Immediate mandibular loading with immediate full-arch implant-supported and screw-retained restorations is a viable treatment alternative, yielding a 100% success rate in this small series of patients.

  17. Monopolar Stimulation of the Implanted Cochlea: A Synthetic Population-Based Study

    DEFF Research Database (Denmark)

    Mangado Lopez, Nerea; Ceresa, Mario; Dejea Velardo, Hector

    2016-01-01

    Cochlear implantation is carried out to recover the sense of hearing. However, its functional outcome varies highly between patients. In the current work, we present a study to assess the functional outcomes of cochlear implants considering the inter-variability found among a population of patien...

  18. Axial relationship between dental implants and teeth/implants: a radiographic study.

    Science.gov (United States)

    Machtei, Eli E; Oettinger-Barak, Orit; Horwitz, Jacob

    2014-08-01

    The relationship of dental implants with neighboring teeth will affect both occlusal relationship and distribution of forces; thus, the purpose of this study was to examine implants' axial relationship with adjacent and opposing teeth/implants. Data of dental implants patients was retrieved. Panoramic X rays were digitized. Computer-based software was used to measure the angular relationship between the implants and adjacent/opposing teeth and implants. Data was further sorted by the mode of placement and implants position. 50 patients (219 implants) were included. Mean angle to adjacent tooth/implant was 178.71° ± 9.18° (range 129.7°-206°). Implants were more parallel to adjacent teeth (180.99° ± 1.06°) than to adjacent implants (176.32° ± 0.54°; P = .0001). Mean angular relationship to opposite tooth was 167.88° ± 8.92° (range 137.7°-179.8°). Implants that were placed freehand or with positional guide had similar intra-arch relationship (178.22° and 178.81°, respectively) and similar inter-arch angulations (164.46° and 167.74°). Molars had greater deviation of the angular relationship (175.54°) compared to premolars (181.62°) and incisors (180.55°, P = .0001). Implants placed in the maxilla had smaller axial deviation compared to implants in the mandible (180.41° ± 0.64 vs 177.14° ± 1.02; P = .0081). Good axial relationship may be obtained in most implants placed by an experienced clinician, even when placed freehand. The mandibular posterior region is more prone to axial deviation and as such requires special attention.

  19. A Longitudinal Study in Children with Sequential Bilateral Cochlear Implants: Time Course for the Second Implanted Ear and Bilateral Performance

    Science.gov (United States)

    Reeder, Ruth M.; Firszt, Jill B.; Cadieux, Jamie H.; Strube, Michael J.

    2017-01-01

    Purpose: Whether, and if so when, a second-ear cochlear implant should be provided to older, unilaterally implanted children is an ongoing clinical question. This study evaluated rate of speech recognition progress for the second implanted ear and with bilateral cochlear implants in older sequentially implanted children and evaluated localization…

  20. A Longitudinal Study in Children with Sequential Bilateral Cochlear Implants: Time Course for the Second Implanted Ear and Bilateral Performance

    Science.gov (United States)

    Reeder, Ruth M.; Firszt, Jill B.; Cadieux, Jamie H.; Strube, Michael J.

    2017-01-01

    Purpose: Whether, and if so when, a second-ear cochlear implant should be provided to older, unilaterally implanted children is an ongoing clinical question. This study evaluated rate of speech recognition progress for the second implanted ear and with bilateral cochlear implants in older sequentially implanted children and evaluated localization…

  1. Investigation of pathogenic genes in peri-implantitis from implant clustering failure patients: a whole-exome sequencing pilot study.

    Directory of Open Access Journals (Sweden)

    Soohyung Lee

    Full Text Available Peri-implantitis is a frequently occurring gum disease linked to multi-factorial traits with various environmental and genetic causalities and no known concrete pathogenesis. The varying severity of peri-implantitis among patients with relatively similar environments suggests a genetic aspect which needs to be investigated to understand and regulate the pathogenesis of the disease. Six unrelated individuals with multiple clusterization implant failure due to severe peri-implantitis were chosen for this study. These six individuals had relatively healthy lifestyles, with minimal environmental causalities affecting peri-implantitis. Research was undertaken to investigate pathogenic genes in peri-implantitis albeit with a small number of subjects and incomplete elimination of environmental causalities. Whole-exome sequencing was performed on collected saliva samples via self DNA collection kit. Common variants with minor allele frequencies (MAF > = 0.05 from all control datasets were eliminated and variants having high and moderate impact and loss of function were used for comparison. Gene set enrichment analysis was performed to reveal functional groups associated with the genetic variants. 2,022 genes were left after filtering against dbSNP, the 1000 Genomes East Asian population, and healthy Korean randomized subsample data (GSK project. 175 (p-value <0.05 out of 927 gene sets were obtained via GSEA (DAVID. The top 10 was chosen (p-value <0.05 from cluster enrichment showing significance of cytoskeleton, cell adhesion, and metal ion binding. Network analysis was applied to find relationships between functional clusters. Among the functional groups, ion metal binding was located in the center of all clusters, indicating dysfunction of regulation in metal ion concentration might affect cell morphology or cell adhesion, resulting in implant failure. This result may demonstrate the feasibility of and provide pilot data for a larger research

  2. The Carina© middle ear implant: surgical and functional outcomes.

    Science.gov (United States)

    Bruschini, Luca; Berrettini, Stefano; Forli, Francesca; Murri, Alessandra; Cuda, Domenico

    2016-11-01

    The Carina© system (Cochlear Ltd, Sydney, Australia) is a totally implantable prosthesis designed to meet the needs of acoustic amplification in adults with moderate-to-severe sensorineural or mixed hearing loss. It mechanically stimulates the ossicles or labyrinthine windows. The object of this study was to update surgical and functional results obtained in a consistent sample of Carina© recipients. The data sheets of 26 patients who underwent Carina© surgery at two ENT units [i.e., ENT Audiology and Phoniatrics Unit of the University Hospital of Pisa (Pisa, Italy) and ENT Unit of "Guglielmo da Saliceto" Hospital of Piacenza (Piacenza, Italy)] were evaluated for the surgical and audiological outcomes. Twenty patients received a unilateral device, whereas six patients were bilaterally implanted (simultaneously in one patient and sequentially in the remaining five patients). The total number of ears implanted in this study was 32. Most implanted patients expressed a high degree of satisfaction with the prosthesis, which highlights the improvement in hearing in different environmental conditions, the cosmetic advantages, and greater freedom in performing common activities in daily living. Audiological examination demonstrated valid functional gain and significant improvement in speech perception in quiet. Based on this experience, the Carina© is a valid alternative to hearing aids. Moreover, a bilateral implantation, even a simultaneous implantation, is a viable option for selected motivated patients because the intervention is generally well tolerated and the surgery time is relatively fast.

  3. Adding functionality with additive manufacturing: Fabrication of titanium-based antibiotic eluting implants

    Energy Technology Data Exchange (ETDEWEB)

    Cox, Sophie C. [School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Jamshidi, Parastoo [School of Materials and Metallurgy, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Eisenstein, Neil M. [School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Royal Centre for Defence Medicine, Birmingham Research Park, Vincent Drive, Edgbaston B15 2SQ (United Kingdom); Webber, Mark A. [School of Biosciences, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Hassanin, Hany [School of Materials and Metallurgy, University of Birmingham, Edgbaston B15 2TT (United Kingdom); School of Mechanical and Automotive Engineering, Kingston University, London SW15 3DW (United Kingdom); Attallah, Moataz M. [School of Materials and Metallurgy, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Shepherd, Duncan E.T. [Department of Mechanical Engineering, School of Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Addison, Owen [School of Dentistry, University of Birmingham, Edgbaston B15 2TT (United Kingdom); Grover, Liam M. [School of Chemical Engineering, University of Birmingham, Edgbaston B15 2TT (United Kingdom)

    2016-07-01

    Additive manufacturing technologies have been utilised in healthcare to create patient-specific implants. This study demonstrates the potential to add new implant functionality by further exploiting the design flexibility of these technologies. Selective laser melting was used to manufacture titanium-based (Ti-6Al-4V) implants containing a reservoir. Pore channels, connecting the implant surface to the reservoir, were incorporated to facilitate antibiotic delivery. An injectable brushite, calcium phosphate cement, was formulated as a carrier vehicle for gentamicin. Incorporation of the antibiotic significantly (p = 0.01) improved the compressive strength (5.8 ± 0.7 MPa) of the cement compared to non-antibiotic samples. The controlled release of gentamicin sulphate from the calcium phosphate cement injected into the implant reservoir was demonstrated in short term elution studies using ultraviolet-visible spectroscopy. Orientation of the implant pore channels were shown, using micro-computed tomography, to impact design reproducibility and the back-pressure generated during cement injection which ultimately altered porosity. The amount of antibiotic released from all implant designs over a 6 hour period (< 28% of the total amount) were found to exceed the minimum inhibitory concentrations of Staphylococcus aureus (16 μg/mL) and Staphylococcus epidermidis (1 μg/mL); two bacterial species commonly associated with periprosthetic infections. Antibacterial efficacy was confirmed against both bacterial cultures using an agar diffusion assay. Interestingly, pore channel orientation was shown to influence the directionality of inhibition zones. Promisingly, this work demonstrates the potential to additively manufacture a titanium-based antibiotic eluting implant, which is an attractive alternative to current treatment strategies of periprosthetic infections. - Highlights: • Titanium implants were additively manufactured with surface connected reservoirs. • Implants

  4. Executive Functioning Skills in Preschool-Age Children with Cochlear Implants

    Science.gov (United States)

    Beer, Jessica; Kronenberger, William G.; Castellanos, Irina; Colson, Bethany G.; Henning, Shirley C.; Pisoni, David B.

    2014-01-01

    Purpose: The purpose of this study was to determine whether deficits in executive functioning (EF) in children with cochlear implants (CIs) emerge as early as the preschool years. Method: Two groups of children ages 3 to 6 years participated in this cross-sectional study: 24 preschoolers who had CIs prior to 36 months of age and 21 preschoolers…

  5. A glass fiber-reinforced composite - bioactive glass cranioplasty implant: A case study of an early development stage implant removed due to a late infection.

    Science.gov (United States)

    Posti, Jussi P; Piitulainen, Jaakko M; Hupa, Leena; Fagerlund, Susanne; Frantzén, Janek; Aitasalo, Kalle M J; Vuorinen, Ville; Serlo, Willy; Syrjänen, Stina; Vallittu, Pekka K

    2015-03-01

    This case study describes the properties of an early development stage bioactive glass containing fiber-reinforced composite calvarial implant with histology that has been in function for two years and three months. The patient is a 33-year old woman with a history of substance abuse, who sustained a severe traumatic brain injury later unsuccessfully treated with an autologous bone flap and a custom-made porous polyethylene implant. She was thereafter treated with developmental stage glass fiber-reinforced composite - bioactive glass implant. After two years and three months, the implant was removed due to an implant site infection. The implant was analyzed histologically, mechanically, and in terms of chemistry and dissolution of bioactive glass. Mechanical integrity of the load bearing fiber-reinforced composite part of the implant was not affected by the in vivo period. Bioactive glass particles demonstrated surface layers of hydroxyapatite like mineral and dissolution, and related increase of pH was considerably less after two and three months period than that for fresh bioactive glass. There was a difference in the histology of the tissues inside the implant areas near to the margin of the implant that absorbed blood during implant installation surgery, showed fibrous tissue with blood vessels, osteoblasts, collagenous fibers with osteoid formation, and tiny clusters of more mature hard tissue. In the center of the implant, where there was less absorbed blood, only fibrous tissue was observed. This finding is in line with the combined positron emission tomography - computed tomography examination with (18F)-fluoride marker, which demonstrated activity of the mineralizing bone by osteoblasts especially at the area near to the margin of the implant 10 months after implantation. Based on these promising reactions found in the bioactive glass containing fiber-reinforced composite implant that has been implanted for two years and three months, calvarial

  6. Functional recovery in spinal cord injured rats using polypyrrole/iodine implants and treadmill training.

    Science.gov (United States)

    Alvarez-Mejia, Laura; Morales, Juan; Cruz, Guillermo J; Olayo, María-Guadalupe; Olayo, Roberto; Díaz-Ruíz, Araceli; Ríos, Camilo; Mondragón-Lozano, Rodrigo; Sánchez-Torres, Stephanie; Morales-Guadarrama, Axayacatl; Fabela-Sánchez, Omar; Salgado-Ceballos, Hermelinda

    2015-07-01

    Currently, there is no universally accepted treatment for traumatic spinal cord injury (TSCI), a pathology that can cause paraplegia or quadriplegia. Due to the complexity of TSCI, more than one therapeutic strategy may be necessary to regain lost functions. Therefore, the present study proposes the use of implants of mesoparticles (MPs) of polypyrrole/iodine (PPy/I) synthesized by plasma for neuroprotection promotion and functional recovery in combination with treadmill training (TT) for neuroplasticity promotion and maintenance of muscle tone. PPy/I films were synthesized by plasma and pulverized to obtain MPs. Rats with a TSCI produced by the NYU impactor were divided into four groups: Vehicle (saline solution); MPs (PPy/I implant); Vehicle-TT (saline solution + TT); and MPs-TT (PPy/I implant + TT). The vehicle or MPs (30 μL) were injected into the lesion site 48 h after a TSCI. Four days later, TT was carried out 5 days a week for 2 months. Functional recovery was evaluated weekly using the BBB motor scale for 9 weeks and tissue protection using histological and morphometric analysis thereafter. Although the MPs of PPy/I increased nerve tissue preservation (P = 0.03) and promoted functional recovery (P = 0.015), combination with TT did not produce better neuroprotection, but significantly improved functional results (P = 0.000) when comparing with the vehicle group. So, use these therapeutic strategies by separately could stimulate specific mechanisms of neuroprotection and neuroregeneration, but when using together they could mainly potentiate different mechanisms of neuronal plasticity in the preserved spinal cord tissue after a TSCI and produce a significant functional recovery. The implant of mesoparticles of polypyrrole/iodine into the injured spinal cord displayed good integration into the nervous tissue without a response of rejection, as well as an increased in the amount of preserved tissue and a better functional recovery than the group without

  7. Impact of dental implant insertion method on the peri-implant bone tissue--an experimental study.

    Science.gov (United States)

    Stamatović, Novak; Matić, Smiljana; Tatić, Zoran; Petković-Curcin, Aleksandra; Vojvodić, Danilo; Rakić, Mia

    2013-09-01

    The function of dental implants depends on their stability in bone tissue over extended period of time, i.e. on osseointegration. The process through which osseointegration is achieved depends on several factors, surgical insertion method being one of them. The aim of this study was to histopathologically compare the impact of the surgical method of implant insertion on the peri-implant bone tissue. The experiment was performed on 9 dogs. Eight weeks following the extraction of lower premolars implants were inserted using the one-stage method on the right mandibular side and two-stage method on the left side. Three months after implantation the animals were sacrificed. Three distinct regions of bone tissue were histopathologically analyzed, the results were scored and compared. In the specimens of one-stage implants increased amount of collagen fibers was found in 5 specimens where tissue necrosis was also observed. Only moderate osteoblastic activity was found in 3 sections. The analysis of bone-to-implant contact region revealed statistically significantly better results regarding the amount of collagen tissue fibers for the implants inserted in the two-stage method (Wa = 59 osteocytes in 3 specimens. No necrotic tissue was found. The analyzed specimens of bone adjacent to two-stage implants revealed a moderate increase in the number of osteocytes in 3 and a marked increase in 6 specimens respectively. This difference was statistically significant (Wb = 106.5 > 105, alpha = 0.05). No necrosis and osteoblastic activity were observed. Better results were achieved by the two-stage method in bone-to-implant contact region regarding the amount of collagen tissue, while the results were identical regarding the osteoblastic activity and bone tissue necrosis. There was no difference between the methods in the bone-implant interface region. In the bone tissue adjacent to the implant the results were identical regarding the amount of collagen tissue, osteoblastic reaction

  8. Progressive plateau root form dental implant osseointegration: A human retrieval study.

    Science.gov (United States)

    Gil, Luiz F; Suzuki, Marcelo; Janal, Malvin N; Tovar, Nick; Marin, Charles; Granato, Rodrigo; Bonfante, Estevam A; Jimbo, Ryo; Gil, Jose N; Coelho, Paulo G

    2015-08-01

    Although preclinical and sparse human histology retrieval studies have shown that the interface between implant and bone is constantly remodeling, no human retrieval database has been developed to determine the effect of functional loading time and other clinical/implant design variables on osseointegration. The present study tested the hypothesis that bone-to-implant contact (BIC) and bone area fraction occupancy (BAFO) increase over functional loading time around dental implants. Due to prosthetic retreatment reasons, 93 human implant retrievals from the same manufacturer (Bicon LLC, Boston, MA, USA) were obtained over a period of approximately 15 years. The retrieved implants were under functional loading from 120 days to ∼18 years and were histomorphologic/metrically evaluated. BIC/BAFO were assessed as a function of multiple independent variables: implant surface type, diameter, length, jaw (maxilla/mandible), region (anterior/posterior), and time of functional loading. The results showed that both BIC and BAFO increased over time independently of implant design/clinical variables, supporting the postulated hypothesis.

  9. Dental implants in medically complex patients-a retrospective study.

    Science.gov (United States)

    Manor, Yifat; Simon, Roy; Haim, Doron; Garfunkel, Adi; Moses, Ofer

    2017-03-01

    Dental implant insertion for oral rehabilitation is a worldwide procedure for healthy and medically compromised patients. The impact of systemic disease risks on the outcome of implant therapy is unclear, since there are few if any published randomized controlled trials (RCTs). The objective of this study is to investigate the rate of complications and failures following dental implantation in medically compromised patients in order to elucidate risk factors and prevent them. A retrospective cohort study was conducted from patient files treated with dental implantation between the years 2008-2014. The study group consisted of medically complex patients while the control group consisted of healthy patients. Preoperative, intraoperative, and post operative clinical details were retrieved from patients' files. The survival rate and the success rate of the dental implants were evaluated clinically and radiographically. A total of 204 patients (1003 dental implants) were included in the research, in the study group, 93 patients with 528 dental implants and in the control group, 111 patients with 475 dental implants. No significant differences were found between the groups regarding implant failures or complications. The failure rate of dental implants among the patients was 11.8 % in the study group and 16.2 % in the control group (P = 0.04). It was found that patients with a higher number of implants (mean 6.8) had failures compared with patients with a lower number of implants (mean 4.2) regardless of their health status (P dental implantation in medically complex patients and in healthy patients. Medically complex patients can undergo dental implantation. There are similar rates of complications and failures of dental implants in medically complex patients and in healthy patients.

  10. Implant-supported single-tooth restorations: a 5-year prospective study.

    Science.gov (United States)

    Wennström, Jan L; Ekestubbe, Annika; Gröndahl, Kerstin; Karlsson, Stig; Lindhe, Jan

    2005-06-01

    Comparatively few studies are available reporting at least 5 years of follow-up data of implant-supported single-tooth replacements. To evaluate prospectively the 5-year outcome of implant-supported single-tooth prosthetic restorations. Forty subjects (mean age 41 years), 23 males and 17 females, who required single-tooth prosthetic replacement for a missing tooth were recruited. A total of 45 self-tapping implants (Astra Tech ST-implants)--40 in the maxilla and five in the mandible--were installed in a two-stage procedure. Abutment connection was performed 3-6 months after implant installation. Clinical and radiographic examinations were performed at the completion of the prosthetic treatment and once a year during a 5-year follow-up period. The analysis of peri-implant bone level alteration was performed on subject and implant levels and by the use of analysis of variance and binary logistic regression. Three patients were lost during the 5 years of follow-up. One implant was lost after 2.5 years in function and another four implants could not be accounted for at the 5-year follow-up examination. The overall failure rate at 5 years was 2.6% (subject level) and 2.3% (implant level). The mean loss of marginal bone at the implants during the first year in function was 0.06 mm (SD 0.67) on the subject level and 0.02 mm (0.65) on the implant level. During the subsequent 4 years the annual change in peri-implant bone level amounted to -0.02 mm (0.22) on both subject and implant levels. Thus, the mean total bone level change over the 5-year interval was -0.14 mm (1.04) on subject level and -0.11 mm (1.00) on the implant level of analysis (p>0.05). The frequency of implants with a 5-year bone loss of > or =1 mm was 13%. Approximately 50% of the implants demonstrated no bone loss. The present clinical trial on single-tooth replacements with the Astra Tech implant system demonstrated that the bone loss during the first year of function as well as annually thereafter was

  11. Maxillary sinus function after sinus lifts for the insertion of dental implants

    NARCIS (Netherlands)

    Timmenga, NM; Raghoebar, GM; Boering, G; VanWeissenbruch, R

    Purpose: The influence of bone augmentation of the floor of the maxillary sinus for the insertion of denial implants on sinus function has not been well investigated, In this study, the influence of the sinus lift on the development of maxillary sinus pathology was evaluated using generally accepted

  12. HORMONAL INFLUENCES ON THE OVARIAN FUNCTION AND THE IMPLANTATION PROCESS IN GUINEA PIGS

    Institute of Scientific and Technical Information of China (English)

    LIUCheng-Quan; DAIMao-Zheng; SHENShu-Ren; WANGZhong-Xing

    1989-01-01

    The influence of peptides and steroid hormones on ovarian function and implantation was studied in guinea pigs. Results show that injections of 5ng LHRH in pulses of onc-hour interval 10 times per day, starting from 20-30 days of age, could induce the first vaginal

  13. Assessment of morphological-functional state of children with cochlear implants

    Directory of Open Access Journals (Sweden)

    Pysanko V.M.

    2016-10-01

    Full Text Available Purpose: assessment of morphological-functional state of pre-school age children with cochlear implants and substantiation of need in post-operative rehabilitation in period of preparation for comprehensive school. Material: we tested weakly hearing children with cochlear implants (n=127, age - 5.6±0.6 years. They were the main group. Control group consisted of children with normal hearing (n=70, age - 5.7±0.4 years. Morphological-functional state was assessed by indicators of physical and biological condition, visual analyzer, posture parameters and foot arch, muscular system and level of coordination. We calculated index of integral morphological-functional state assessment. Results: Morphological functional state of most of children (with cochlear implants was characterized by low physical condition indicators and disharmony. We observed delay in biological development. Index of morphological-functional state integral assessment witnesses, that such child can not study in comprehensive school. Rehabilitation program can reduce the gap between children with normal hearing and those with cochlear implants. Conclusions: Rehabilitation program facilitates quicker domestic and social rehabilitation of children at the account of widening the circle of communication, learning new actions and conceptions. It can permit for such children to study at school together with their healthy peers.

  14. Changes in Tinnitus after Cochlear Implantation and Its Relation with Psychological Functioning

    NARCIS (Netherlands)

    Kloostra, Francka J. J.; Arnold, Rosemarie; Hofman, Rutger; Van Dijk, Pim

    2015-01-01

    This study retrospectively assessed the prevalence of tinnitus in cochlear implant patients and the changes after implantation in 212 patients implanted between 2000 and 2009. Patients were included at least 6 months after implantation and received 2 sets of questionnaires, one about the situation b

  15. What do patients expect from treatment with Dental Implants? Perceptions, expectations and misconceptions: a multicenter study.

    Science.gov (United States)

    Yao, Jie; Li, Ming; Tang, Hua; Wang, Peng-Lai; Zhao, Yu-Xiao; McGrath, Colman; Mattheos, Nikos

    2017-03-01

    While research in terms of patient-centered care in implant therapy is growing, few studies have investigated patients' initial perceptions prior to consultation with the implant dentist. The aim of this cross-sectional study was to capture patients' initial information level, perceptions, as well as expectations from the implant therapy. A 34-item questionnaire was developed to investigate patients' preoperative information, perceptions and expectations from treatment with Dental Implants. The study was conducted in three locations (Hong Kong, SiChuan and JiangSu) during 2014-2015 with 277 patients. The main information source about implant therapy was the dentist or hygienist for less than half of the patients (n = 113, 42%). About 62.8% of participants considered that they were in general informed about implants, but only 17.7% felt confident with the information they had. More than 30% of the sample appeared to maintain dangerous misperceptions about Dental Implants: "Dental Implants require less care than natural teeth"; "Treatment with Dental Implants is appropriate for all patients with missing teeth"; "Dental Implants last longer than natural teeth"; and "Treatments with Dental Implants have no risks or complications." Patients were divided when asked whether "Dental Implants are as functional as natural teeth" (agreement frequency = 52.7%). Expectations from treatment outcome were commonly high, while there was a significant correlation between the overall mean of perception scores and outcome expectation scores (r = 0.32, P dental team would need to diagnose and correct prior to initiating implant treatment. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. Stabilization of mandibular complete dentures by four mini implants: Impact on masticatory function.

    Science.gov (United States)

    Batisse, C; Bonnet, G; Bessadet, M; Veyrune, J L; Hennequin, M; Peyron, M A; Nicolas, E

    2016-07-01

    The frequent instability of mandibular removable complete dentures causes an alteration of mastication. An innovative therapeutic strategy involves placing four symphyseal mini implants. This study aimed at assessing the development of masticatory parameters and the impact on quality of life in subjects that underwent this procedure. Eleven edentulous subjects (mean age 72±11 years) with unstable mandibular complete dentures were followed-up before (T0) and two - three months after (T1) mini implant setting. Physiological parameters (number of cycles, duration of sequence and frequency of mastication) during the mastication of food models and the bolus median particle size (d50) of carrot were evaluated at each time. Quality of life was assessed at T0 and T1 using the Global Oral Health Assessment Index (GOHAI). Parametric tests were used to test relationships between mastication, quality of life variations and mini implant setting, and to compare each parameter mean value at times T0 and T1. More subjects were able to chew carrot after setting the mini implants (8 subjects compared to 4 at T0). This improvement was accompanied by changes in kinematic parameters when chewing carrots, soft and hard model food, and by an improvement of their quality of life. However, the particle size values observed in the bolus remained higher than for normal dentate subjects (9.2±2.8mm). These results indicated that the placement of mini implants as retentive elements for mandibular full dentures had a positive impact on patients' masticatory function and quality of life. The placement of mini implants has a positive impact on the masticatory function and oral health quality of life. The results suggest that this alternative procedure can be used as a treatment option for patients unable to receive conventional implants. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Clinical Evaluation of Small Diameter Straumann Implants in Partially Edentulous Patients: A 5-Year Retrospective Study

    Directory of Open Access Journals (Sweden)

    S. OZER

    2011-06-01

    Full Text Available Objective: The aim of the present study was to retrospectively evaluate small-diameter (3.3 mm Straumann® dental implants placed in the maxilla or the mandible over a period of 5 years in function.Materials and Methods: Twenty- eight partially edentulous patients received a total of 48 implants over a 5-year period. After the standard healing period (3 to 6 months, the implants were restored with single-tooth prostheses or fixed partial dentures. All patients were followed according to a strict maintenance program with regular recalls. The cumulative survival rates of implants were analyzed and prosthetic complications were assessed.Results: After 5 years of function, one single 10-mm-long implant in the maxillary premolar region was lost because of recurrent peri-implant infection in a female patient. Two single 10-mm-long maxillary implants placed in the posterior region were lost due to body fracture. The cumulative 5-year survival rate of the implants was 93.75 %. The most common prosthetic complication was loosening of the occlusal screw.Conclusion: Within the limited observation period and the number of patients included in this study, it may be concluded that the use of small-diameter implants appears to be predictable if clinical guidelines are followed and appropriate prosthetic restorations are provided. However, it should be noted that fatigue fracture may occur.

  18. Bone reactions at implants subjected to experimental peri-implantitis and static load. A study in the dog

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2002-01-01

    AIM: The aim of the present experiment was to study peri-implant tissue reactions to lateral static load at implants subjected to experimental mucositis or peri-implantitis. MATERIAL AND METHODS: 5 beagle dogs were used. The mandibular premolars were extracted. After 12 weeks, 3 implants were ins...

  19. Exfoliative cytology and titanium dental implants: a pilot study.

    Science.gov (United States)

    Olmedo, Daniel G; Nalli, Gabriela; Verdú, Sergio; Paparella, María L; Cabrini, Rómulo L

    2013-01-01

    Oral exfoliative cytology is a diagnostic method that involves the study of cells exfoliated from the oral mucosa. Ions/particles released from metallic implants can remain in the peri-implant milieu. The aim of the present study is to assess the presence of metal particles in cells exfoliated from peri-implant oral mucosa around titanium dental implants. The study comprised 30 patients carrying titanium dental implants, who had neither a metallic prosthesis nor metal restorations in neighboring teeth. Individuals undergoing orthodontic therapy and those who had oral piercing were also excluded from the study. The study sample included patients with and without peri-implantitis. Cytologic samples of the peri-implant area were collected. Samples of the marginal gingiva on the contralateral side of the implant were taken from the same individuals to serve as control. Cytologic analysis was performed using light microscopy. Titanium concentration was determined using inductively coupled plasma-mass spectrophotometry. Metal-like particles were observed inside and outside epithelial cells and macrophages in cytologic smears of peri-implant mucosa of both patients with and without peri-implantitis. No particles were found in the control cytologic samples. The concentration of titanium was higher in the peri-implantitis group compared with the group without peri-implantitis; no traces of titanium were observed in controls. Regardless of an inflammatory response, ions/particles are released from the surface of the implant into the biologic milieu. Exfoliative cytology is a simple technique that may be used to detect metal particles in cells exfoliated from the peri-implant mucosa.

  20. PLEPS study of ions implanted RAFM steels

    Science.gov (United States)

    Sojak, S.; Slugeň, V.; Egger, W.; Ravelli, L.; Petriska, M.; Veterníková, J.; Stacho, M.; Sabelová, V.

    2014-04-01

    Current nuclear power plants (NPP) require radiation, heat and mechanical resistance of their structural materials with the ability to stay operational during NPP planned lifetime. Radiation damage much higher, than in the current NPP, is expected in new generations of nuclear power plants, such as Generation IV and fusion reactors. Investigation of perspective structural materials for new generations of nuclear power plants is among others focused on study of reduced activation ferritic/martensitic (RAFM) steels. These steels have good characteristics as reduced activation, good resistance to volume swelling, good radiation, and heat resistance. Our experiments were focused on the study of microstructural changes of binary Fe-Cr alloys with different chromium content after irradiation, experimentally simulated by ion implantations. Fe-Cr alloys were examined, by Pulsed Low Energy Positron System (PLEPS) at FRM II reactor in Garching (Munich), after helium ion implantations at the dose of 0.1 C/cm2. The investigation was focused on the chromium effect and the radiation defects resistivity. In particular, the vacancy type defects (monovacancies, vacancy clusters) have been studied. Based on our previous results achieved by conventional lifetime technique, the decrease of the defects size with increasing content of chromium is expected also for PLEPS measurements.

  1. Electropolishing of Stainless Steel Implants for Stable Functional Osteosynthesis

    Directory of Open Access Journals (Sweden)

    Omel’chuk, A.О.

    2016-01-01

    Full Text Available A new method for the electropolishing stainless steel for stable functional osteosynthesis has been developed. The polishing of implants was carried out in solutions, based on the ternary system H2SO4—H3PO4—H2O with stepwise decreasing the current density and increasing the orthophosphoric acid concentration. The optimal polishing conditions (current density, solution composition, temperature and duration have been determined. The developed method improves the quality and mechanical properties of the surface.

  2. Peri-implant biomechanical responses to standard, short-wide, and mini implants supporting single crowns under axial and off-axial loading (an in vitro study).

    Science.gov (United States)

    Kheiralla, Lamia Sayed; Younis, Jihan Farouk

    2014-02-01

    This study compared the biomechanical responses of 3 single crowns supported by 3 different implants under axial and off-axial loading. A standard implant (3.75 mm diameter, 13 mm length), a mini implant (3 mm diameter, 13 mm length), and a short-wide implant (5.7 mm diameter, 8 mm length) were embedded in epoxy resin by the aid of a surveyor to ensure their parallelism. Each implant supported a full metal crown made of Ni-Cr alloy with standardized dimensions. Strain gauges and finite element analysis (FEA) were used to measure the strain induced under axial and off-axial functional loads of 300 N. Results showed that mini implants recorded the highest microstrains, under both axial and off-axial loading. All implants showed a considerable increase in strain values under off-axial loading. Standard and short-wide implants proved to be preferable in supporting crowns, as the standard implant showed the lowest strains under axial and off-axial loading using FEA simulation, while the short-wide implant showed the lowest strains under nonaxial loading using strain gauge analysis.

  3. Fabrication of Ti/HA composite and functionally graded implant by three-dimensional printing.

    Science.gov (United States)

    Qian, Chao; Zhang, Fuqiang; Sun, Jian

    2015-01-01

    The aim of this study is to evaluate the feasibility of fabricating titanium(Ti)/hydroxyapatite(HA) composite and functionally graded implant by three-dimensional printing (3DP) technology. Nano-scale Ti and HA powders were mixed at the ratio of 8:2 and prepared with water-soluble binder. The Ti/HA composite CAD model was designed to be in cylinder shape (25 mm in diameter, 20 mm in height) with the 100% bond area in each layer. The functionally graded implant was 25 mm in diameter and 10 mm in height with two segments. The upper segment was composed of 100% Ti in each layer, whereas the lower was composed of 80%Ti/20%HA. The composite and functionally graded implant were fabricated by 3DP and sintered at 1200°C under protective argon atmosphere. There occurred a chemical reaction between Ti and HA, in which new resultants of Ca3(PO4)2, CaTiO3, TiO2 and CaO were created. The sintered Ti/HA composite had the aperture size from 50 to 150 μm and the compressive strength of 184.3±27.1 MPa. The result of this study demonstrated that it was feasible to fabricate Ti/HA composite and functionally graded implant by 3DP technology. The microstructure and mechanical properties of Ti/HA composite and functionally graded implant were conductive to bone cell ingrowth, resulting in the wide application of this biocomposite.

  4. Dental implants in persons with severe epilepsy and multiple disabilities: a long-term retrospective study.

    Science.gov (United States)

    Cune, Marco S; Strooker, Hans; van der Reijden, Willy A; de Putter, Cornelis; Laine, Maria L; Verhoeven, Jan Willem

    2009-01-01

    A retrospective study on the performance of endosseous implants in a population of patients with severe epilepsy and additional motor and/or intellectual impairments was performed. All residents of an inpatient center for persons affected by severe, refractory epilepsy and multiple disabilities who received endosseous implants between 1991 and April 2007 were included in the study. Implant survival was analyzed using the Kaplan-Meier method. A subset of patients who were treated between 1991 and 2004 was invited to participate in a clinical and radio?graphic evaluation in 2004 and 2005. A total of 61 patients were treated between 1991 and April 2007 (n=134 implants). Three of these implants in three different patients failed during the observation period, demonstrating an estimated probability of functional implant survival of 97.6% (SE 1.4%) after 16 years. In patients who were seen during the clinical evaluation in 2004 (n=76 implants), only mild inflammation of the peri-implant mucosa was generally observed (Gingival-Bleeding Index=1), despite the fact that the level of oral hygiene was considered inadequate around 55 of 76 implants (72%). Obvious signs of drug-induced gingival hyperplasia in relation to the implants were not observed. Probing depths averaged approximately 2 mm. Stable marginal bone levels were observed on the radiographs. Dental implant treatment in a population of patients with severe epilepsy and additional disabilities seems to be a viable treatment option. Implant loss is rare. Although adequate plaque control was not feasible in all patients, marginal bone levels remained stable.

  5. Patient perceptions of implantable cardioverter-defibrillator deactivation discussions: A qualitative study

    Directory of Open Access Journals (Sweden)

    Jane MacIver

    2016-04-01

    Full Text Available Background: There is a class I recommendation for implantable cardioverter-defibrillator deactivation discussions to occur between physicians and heart failure patients. Few studies have reported the patient’s perspective on the timing of implantable cardioverter-defibrillator deactivation discussions. Aim: To determine patient awareness, preferences and timing of implantable cardioverter-defibrillator deactivation discussions. Design: Grounded theory was used to collect and analyze interview data from 25 heart failure patients with an implantable cardioverter-defibrillator. Setting and participants: Patients with an implantable cardioverter-defibrillator, from the Heart Function Clinic at University Health Network (Toronto, Canada. Results: The sample (n = 25 was predominately male (76% with an average age of 62 years. Patients identified three stages where they felt implantable cardioverter-defibrillator deactivation should be discussed: (1 prior to implantation, (2 with any significant deterioration but while they were of sound mind to engage in and communicate their preferences and (3 at end of life, where patients wished further review of their previously established preferences and decisions about implantable cardioverter-defibrillator deactivation. Most patients (n = 17, 68% said they would consider deactivation, six (24% were undecided and two (8% were adamant they would never turn it off. Conclusion: The patient preferences identified in this study support the need to include information on implantable cardioverter-defibrillator deactivation at implant, with change in clinical status and within broader discussions about end-of-life treatment preferences. Using this process to help patients determine and communicate their implantable cardioverter-defibrillator deactivation preferences may reduce the number of patients experiencing distressing implantable cardioverter-defibrillator shocks at end of life.

  6. Spiral Tomography for Determining Implant Angulation: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Z. Dalili Kajan

    2008-06-01

    Full Text Available Objective: To study the accuracy of spiral tomography in the determination of implant angulation.Materials and Methods: Eighteen gutta-percha filled points on dry mandibles were se-lected for implant placement. A translucent acrylic template was fabricated for each man-dible. After preparing tomographic images (2 mmslice thickness, Cranex Tome, the ideal axis of the implant was traced. The angle between the ideal axis and the tangent line on the alveolar crest in the buccal side was measured and transferred to aluminum sleeves by a protractor. After implant placement, tomographic images were taken again and angles of the actual implants were estimated. In addition, thedistances from the tip of the actual and the supposed implants to the buccal cortex were measured. The data were analyzed by paired sample t test with 95% confidence.Results: Less than two-degreedifference between angles of the supposed and the actual implants was found in 44.4% of the cases, whilst 33.3% revealed more than five-degreedifference. There was a significant statistical difference between the angle of the actual and the supposed implants. There was also a significant statistical difference between the linear distances from the tip of the actual and the supposed implants to buccal cortex(P=0.015Conclusion: Spiral tomography in combination with template may provide acceptable re-sults concerning implant angulation and prediction of cortical perforation risk.

  7. Surface Topographical Changes of a Failing Acid-Etched Long-Term in Function Retrieved Dental Implant.

    Science.gov (United States)

    Monje, Alberto; González-García, Raúl; Fernández-Calderón, María Coronada; Hierro-Oliva, Margarita; González-Martín, María Luisa; Del Amo, Fernando Suarez-Lopez; Galindo-Moreno, Pablo; Wang, Hom-Lay; Monje, Florencio

    2016-02-01

    The aim of the present study was to report the main topographical and chemical changes of a failing 18-year in function retrieved acid-etching implant in the micro- and nanoscales. A partially edentulous 45 year old rehabilitated with a dental implant at 18 years of age exhibited mobility. After careful examination, a 3.25 × 13-mm press-fit dental implant was retrieved. Scanning electron microscope (SEM) analysis was carried out to study topographical changes of the retrieved implant compared with an unused implant with similar topographical characteristics. Moreover, X-ray photoelectron spectroscopy (XPS) analysis was used to study the surface composition of the retrieved failing implant. Clear changes related to the dual dioxide layer are present as visible in ≥×500 magnification. In addition, it was found that, for the retrieved implant, the surface composition consisted mainly of Ti2p, O1s, C1s, and Al2p. Also, a meaningful decrease of N and C was noticed, whereas the peaks of Ti2p, Al2p, and O1s increased when analyzing deeper (up to ×2000s) in the sample. It was shown that the superficial surface of a retrieved press-fit dual acid-etched implant 18 years after placement is impaired. However, the causes and consequences for these changes cannot be determined.

  8. Study of the radiation effect in breast implants

    Energy Technology Data Exchange (ETDEWEB)

    Moreno T, L. R.; Ramirez R, A., E-mail: lumor2000@yahoo.com.mx [Universidad Autonoma Metropolitana, Unidad Azcapotzalco, Departamento de Ciencias Basicas, Av. San Pablo No. 180, Col. Reynosa Tamaulipas, 02200 Mexico D. F. (Mexico)

    2013-10-01

    This breast cancer is one of the most important death causes in women. Among the more frequently medical treatment for advanced breast cancer is the mastectomy. This situation leads to silicone implants as an esthetic option. There have been cases in patients with implants where cancer was frequently detected, in which a conventional radiotherapy is required. In this work is presented a study of the probable adverse effects caused by the application of high power X-rays (6-10 MV) to the silicone implants and to the surrounding tissues. In the research carried out at the clinic, none Bolus effect was detected in patients with implants. Our results prescribe that in the case of patients with implants and frequent breast cancer, the removal of implants is not necessary due radiotherapy works directly in the damaged tissues. (Author)

  9. A 5-year retrospective study on Replace Select Tapered dental implants.

    Science.gov (United States)

    Pettersson, Pelle; Sennerby, Lars

    2015-04-01

    Long-term data regarding survival and crestal bone loss for Replace Select Tapered implants (Nobel Biocare AB, Gothenburg, Sweden) are lacking. The study aims to present the 5-year outcomes from a retrospective analysis of Replace Select Tapered implants placed and restored in consecutive patients. A total of 88 consecutive patients (32 male, 56 female, mean age 65 ± 12 years) treated by one clinician (PP) were clinically and radiographically evaluated during at least 5 years of function. A total of 271 dental implants (Replace Select Tapered, Nobel Biocare AB) with an oxidized surface (TiUnite, Nobel Biocare AB) had been placed in both jaws (228 in the maxilla, 43 in the mandible). The majority of implants were placed in healed sites (n = 244), while 27 implants were immediately placed in extraction sockets. The majority of implants (n = 262) healed for 3 to 4 months prior to loading, and nine implants were immediately loaded. A total of 121 implant-supported restorations were delivered; 42 single tooth replacements, 61 fixed partial bridges, 14 fixed full bridges, and 4 fixed partial implant-tooth connected bridges. The marginal bone level was measured in intraoral radiographs taken after surgery (baseline), and after 1, 2, 3, 4, and 5 years. Fifty-one patients with 160 implants were followed throughout the study. One implant failed at healing abutment connection 4 months after insertion, resulting in a cumulative survival rate of 99.6%. The average crestal bone loss was 0.9 ± 1.6 mm after 1 year and 0.1 mm ± 2.4 after 5 years. There were 14.8% of measured implants that showed more than 2 mm and 5.2% more than 3 mm bone loss after 5 years, with no progression since the 1-year examination. One patient (2.0%) treated with six implants presented with significant crestal bone loss and recurrent peri-implant purulent infections at all implants. The present retrospective 5-year study showed high survival rate and steady crestal bone

  10. Choosing which ear to implant in adult candidates with functional residual hearing.

    Science.gov (United States)

    Fielden, Claire A; Mehta, Rajnikant L; Kitterick, Pádraig T

    2016-04-01

    This study examined whether audiologists consider the potential benefits of contralateral hearing aid use following cochlear implantation when recommending which ear to implant in UK adult candidates with residual hearing. Thirty-four audiologists from providers of adult implantation services completed a decision-choice experiment. Clinicians were willing to consider recommending that the poorer ear be implanted, provided it had been aided continuously, suggesting that their decision making seeks to preserve access to residual hearing in the non-implanted ear where possible. Future approaches to determining candidacy should therefore consider that a sub-set of patients may obtain additional benefit from this residual hearing following implantation.

  11. Photoluminescence study on Eu-implanted GaN

    Institute of Scientific and Technical Information of China (English)

    Zhang Chun-Guang; Bian Liu-Fang; Chen Wei-De

    2005-01-01

    The photoluminescence (PL) properties of Eu-implanted GaN thin films are studied. The experimental results show that the PL intensity is seriously affected by ion implantation conditions. The PL efficiency increases exponentially with annealing temperature increasing up to a maximum temperature of 1050℃. Moreover, the PL intensity for the sample implanted along the channelling direction is nearly twice more than that observed from the sample implanted along the random direction. The thermal quenching of PL intensity from 10K to 300K for sample annealed at 1050℃ is only 42.%.

  12. A função vestibular em indivíduos usuários de implante coclear Vestibular function in cochlear implant users

    Directory of Open Access Journals (Sweden)

    Ariane Solci Bonucci

    2008-04-01

    worsening. 13 % of the patients showed an improvement, and this could be related to the vestibular compensation phenomenon and to electric stimulation. However, it was observed, in the caloric responses, a worsening in the vestibular system function, for both implanted and non-implanted ears. Thus, there is no evidence of more damage to the implanted ear. CONCLUSION: the study showed that cochlear implant surgeries could injure the vestibular system in both ears. However, the vestibular symptoms take place in a smaller proportion, and can improve after cochlear implant surgery.

  13. Prognosis of single molar implants: a retrospective study.

    Science.gov (United States)

    Kim, Young-Kyun; Kim, Su-Gwan; Yun, Pil-Young; Hwang, Jung-Won; Son, Mee-Kyoung

    2010-08-01

    The purpose of this study was to evaluate the short- and mid-term prognosis of maxillary and mandibular single molar implants, prosthetic complications, and factors mediating the effects seen on them. Eighty-seven patients were enrolled consecutively in this study and 96 implants were placed into a single molar defect site by one oral and maxillofacial surgeon from March 2004 to December 2006. Primary osseointegration failure developed in two implants and delayed implant failure occurred at four implants. The fraction surviving interval was 97% to 100%, and at the last follow-up observation, the cumulative survival rate was 91.1%. All failed implants occurred in second molar sites, and the failure rate, according to implant site, showed a significant difference. Prosthetic complications, such as screw loosening, showed a significant correlation to the mesiodistal cantilever. Furthermore, crestal bone loss 3 years after loading was 0.2 mm on average and a very stable result was obtained. Based on the results, the risk of failure for maxillary and mandibular single molar implants is high and the possibility of developing prosthetic complications during loading is also high. Therefore, to minimize the cantilever, implants must be placed precisely and followed carefully and maintained for a long period of time.

  14. Comparative Clinical Study of Conventional Dental Implants and Mini Dental Implants for Mandibular Overdentures: A Randomized Clinical Trial.

    Science.gov (United States)

    Aunmeungtong, Weerapan; Kumchai, Thongnard; Strietzel, Frank P; Reichart, Peter A; Khongkhunthian, Pathawee

    2017-04-01

    Dental implant-retained overdentures have been chosen as the treatment of choice for complete mandibular removable dentures. Dental implants, such as mini dental implants, and components for retaining overdentures, are commercially available. However, comparative clinical studies comparing mini dental implants and conventional dental implants using different attachment for implant-retained overdentures have not been well documented. To compare the clinical outcomes of using two mini dental implants with Equator(®) attachments, four mini dental implants with Equator attachments, or two conventional dental implants with ball attachments, by means of a randomized clinical trial. Sixty patients received implant-retained mandibular overdentures in the interforaminal region. The patients were divided into three groups. In Groups 1 and 2, two and four mini dental implants, respectively, were placed and immediately loaded by overdentures, using Equator(®) attachments. In Group 3, conventional implants were placed. After osseointegration, the implants were loaded by overdentures, using ball attachments. The study distribution was randomized and double-blinded. Outcome measures included changes in radiological peri-implant bone level from surgery to 12 months postinsertion, prosthodontic complications and patient satisfaction. The cumulative survival rate in the three clinical groups after one year was 100%. There was no significant difference (p dental implants with Equator attachments. However, there was a significant difference in marginal bone loss and patient satisfaction between those receiving mini dental implants with Equator attachments and conventional dental implants with ball attachments. The marginal bone resorption in Group 3 was significantly higher than in Groups 1 and 2 (p dental implants can be immediately used successfully for retaining lower complete dentures, as shown after a 1-year follow up. © 2016 Wiley Periodicals, Inc.

  15. A prospective clinical study to evaluate the performance of zirconium dioxide dental implants in single-tooth gaps.

    Science.gov (United States)

    Gahlert, Michael; Kniha, Heinz; Weingart, Dieter; Schild, Sabine; Gellrich, Nils-Claudius; Bormann, Kai-Hendrik

    2016-12-01

    Dental implants have traditionally been made from titanium or its alloys, but recently full-ceramic implants have been developed with comparable osseointegration properties and functional strength properties to titanium. These ceramic implants may have advantages in certain patients and situations, for example, where esthetic outcomes are particularly important. The objective of this investigation was to evaluate the performance of a newly developed full-ceramic ZrO2 monotype implant design (PURE Ceramic Implant; Institut Straumann AG, Basel, Switzerland) in single-tooth gaps in the maxilla and mandible. This was a prospective, open-label, single-arm study in patients requiring implant rehabilitation in single-tooth gaps. Full-ceramic implants were placed, with provisional and final prostheses inserted after 3 and 6 months, respectively. Crestal bone level was measured at implant placement and after 6 and 12 months. Implant survival and success were evaluated after 6 and 12 months. Further evaluations are planned after 24 and 36 months. Forty-six patients were screened for potential study participation, of whom 44 (17 men and 27 women, mean age 48 ± 14 years) were recruited into the study. The majority of implants (90.9%) were placed in the maxilla. The implant survival and implant success rate after 12 months were 97.6%. A minor change of the mean bone level occurred between implant loading (final prosthesis insertion after 6 months) and 12 months (-0.14 mm) after initial bone remodeling was observed between implant placement and loading (-0.88 mm). The results indicated that monotype ceramic implants can achieve clinical outcomes comparable to published outcomes of equivalent titanium implants. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  16. A preliminary study looking at parental emotions following cochlear implantation.

    Science.gov (United States)

    Anagnostou, Flora; Graham, John; Crocker, Susan

    2007-06-01

    This preliminary research investigated the emotions of parents with cochlear implanted children. The object for the research was first to compare four emotions engendered in parents of deaf children before and after cochlear implantation. Second, to monitor changes in these emotions during a period of up to four years after implantation. Third, to see whether any of the emotions studied was significantly more prominent than the others, and fifth to identify any differences in emotions that were related to the gender of parents. A self-report questionnaire was given to 112 participants of whom 53 replied. There were equal groups of parents in two categories, those with children up to two years after implantation, and those two to four years after implantation. The responses were interpreted using parametric statistics. The results highlight that grief is the strongest emotional condition that parents experience before and up to two years after implantation, alongside family adjustments. Parents of the up to two years after implantation group generally have stronger feelings and are less satisfied than parents in the over two years implanted group. Finally, fathers use denial more than mothers. Considerations for future research and implications for paediatric cochlear implant teams will be discussed.

  17. Spectroscopic studies of ion implanted PPV films

    Energy Technology Data Exchange (ETDEWEB)

    Moreau, C. (Cavendish Lab., Univ. of Cambridge (United Kingdom)); Friend, R.H. (Cavendish Lab., Univ. of Cambridge (United Kingdom)); Sarnecki, G.J. (Cavendish Lab., Univ. of Cambridge (United Kingdom)); Lucas, B. (LEPOFI, Faculte des Sciences, 87 - Limoges (France)); Moliton, A. (LEPOFI, Faculte des Sciences, 87 - Limoges (France)); Ratier, B. (LEPOFI, Faculte des Sciences, 87 - Limoges (France)); Belorgeot, C. (Lab. de Physique Moleculaire, Faculte des Sciences, 87 - Limoges (France))

    1993-03-15

    The main results of the spectroscopic analyses (infrared and ultraviolet - visible - near infrared) carried out on PPV films before and after ion implantation with halogen and alkali ions are presented in this paper. The influence of both ions nature and implantation parameters on optical properties of this polymer have been pointed out and the appearance of a weak band due to doping has been observed by infrared spectroscopy. (orig.)

  18. Vestibular Dysfunctions in Cochlear Implant Patients; A Vestibular Evoked Myogenic Potential Study

    Directory of Open Access Journals (Sweden)

    Masoud Motasaddi Zarandy

    2011-12-01

    Full Text Available Background and Aim: Vestibular evoked myogenic potential in response to click or short tone burst stimuli have been used as a clinical test for distinguish saccule and inferior vestibular nerve diseases. Different studies show that cochlear implant could have inverse effects on vestibular structures. We aimed to investigate vestibular evoked myogenic potential in unilateral cochlear implanted individuals in compare to normal individuals.Methods: Thirty-three unilateral cochlear implanted patients (mean age 19.96 years and 30 normal hearing individuals (mean age 24-27 years as control group were enrolled in this cross- sectional study. Absolute latencies and amplitudes of myogenic potential responses were measured and compared in both groups.Results: Myogenic potential recorded in both ears of all controls were normal. No response could be recorded in 16 patients (48.48% from both ears. In three patients, responses were recorded in both ears though the amplitude of waves was reduced in implanted ear. Unilateral response could be recorded in 14 patients only in their non-implanted ear.Conclusion: Vestibular evoked myogenic potential test is a useful tool for assessing saccular function in cochlear implant patients. Damages of osseous spiral lamina and basilar membrane after cochlear implantation could result in dysfunctions of vestibular organs specially saccule. It seems that saccule could be easily damaged after cochlear implantation. This would cause absence or reduced amplitudes in myogenic potential.

  19. Functional outcome and quality of life after a maxillectomy: a comparison between an implant supported obturator and implant supported fixed prostheses in a free vascularized flap.

    Science.gov (United States)

    Wang, Feng; Huang, Wei; Zhang, Chenping; Sun, Jian; Qu, Xingzhou; Wu, Yiqun

    2017-02-01

    Defects of the maxilla caused by tumor resection create high levels of psychological and physical trauma for patients. The application of osseointegrated dental implants using either an obturator prosthesis or a free vascularized flap has tremendously changed the retention and stability of the superstructure. However, no study has been performed to compare the function of the aforementioned two approaches and the quality of life using the subjective assessments of patients. Eligible patients who were treated with maxillary resection and rehabilitated with implant supported obturator prostheses (group 1) or those who received free vascularized flap transfers with implant supported fixed prostheses (group 2) were enrolled between March 2006 and May 2014. A questionnaire that included the indices of the Obturator Functioning Scale (OFS), EORTC Head and Neck 35 assessment and the Mental Health Inventory (MHI) was used to evaluate the functional rehabilitation and QOL of patients in the study. A total of 42 dental implants, including 25 zygomatic implants, were used in 18 patients (mean age: 56.2 ± 12.3 years) in the obturator prostheses in group 1. Twenty patients (mean age: 45.6 ± 14.1 years) who were treated with a vascularized free flap including the fibula (n = 15) and ilium (n = 5) combined with a total of 71 regular implants for fixed prostheses comprised group 2. No statistically significant median differences in the OFS, EORTC Head and Neck assessment and MHI global scale were observed between the groups. On the MHI subscales item-levels, higher median subscale scores exhibited by group 1 than group 2 and had statistically significant difference between the groups (P = 0.024). Within the limitations of this study, it demonstrated no difference in oral function between patients with implant supported obturators and implant supported fixed prostheses in free vascularized flaps after a maxillectomy. However, patients who received obturator therapy

  20. Changes in tinnitus after cochlear implantation and its relation with psychological functioning.

    Science.gov (United States)

    Kloostra, Francka J J; Arnold, Rosemarie; Hofman, Rutger; Van Dijk, Pim

    2015-01-01

    This study retrospectively assessed the prevalence of tinnitus in cochlear implant patients and the changes after implantation in 212 patients implanted between 2000 and 2009. Patients were included at least 6 months after implantation and received 2 sets of questionnaires, one about the situation before implantation and one about the situation after implantation. Mostly standardized questionnaires assessed tinnitus handicap (Tinnitus Handicap Inventory, THI, and Tinnitus Handicap Questionnaire, THQ), tinnitus characteristics, hearing loss (Abbreviated Profile of Hearing Aid Benefit) and anxiety/depression (Hospital Anxiety and Depression Scale). Of the approached patients, 117 completed the full sets of questionnaires and 35 completed a short version. Preoperative tinnitus was reported by 51.3% of these patients, of which 55.6% reported a reduction or cessation of their tinnitus after implantation. However, 8.2% of the patients with tinnitus reported a postoperative deterioration of their tinnitus. In addition, among the patients without preoperative tinnitus, 19.6% reported the start of tinnitus after implantation. The self-reported change of tinnitus correlated with the pre- and postoperative scores on the THI and THQ. The THQ showed slightly more changes in scores after cochlear implantation compared to the THI. Overall hearing handicap and feelings of anxiety and depression decreased after implantation. In conclusion, tinnitus is reduced after cochlear implantation in an important part of the patients, but in a small part implantation has a negative effect on tinnitus. When tinnitus starts after implantation, the tinnitus handicap is mild.

  1. Cochlear implantation in patients with inner ear bone malformations with posterior labyrinth involvement: an exploratory study.

    Science.gov (United States)

    Palomeque Vera, Juan Miguel; Platero Sánchez-Escribano, María; Gómez Hervás, Javier; Fernández Prada, María; González Ramírez, Amanda Rocío; Sainz Quevedo, Manuel

    2016-04-01

    Inner ear bone malformations are one cause of profound sensorineural hearing loss. This investigation focused on those affecting the posterior labyrinth, especially enlarged vestibular aqueduct syndrome, which is associated with fluctuating and progressive hearing loss. The objectives of this study were to analyze the behavior of the electrical stimulation, auditory functionality and linguistic development in patients with inner ear malformations involving the posterior labyrinth. The study included ten patients undergoing cochlear implantation (cases: five with enlarged vestibular aqueduct, two with vestibular aqueduct stenosis/aplasia, and three with semicircular canal disorders). Post-implantation, data were gathered on the electrical stimulation threshold and maximum comfort levels and on the number of functioning electrodes. Evaluation of Auditory Responses to Speech (EARS) subtests were used to assess auditory functionality and language acquisition at 6, 12, and 24 months post-implantation. Results were compared with findings in a control group of 28 cochlear implantation patients without these malformations. No significant differences were found between case and control groups in electrical stimulation parameters; auditory functionality subtest scores were lower in cases than controls, although the difference was only statistically significant for some subtests. In conclusion, cochlear implantation patients with posterior labyrinth bone malformations and profound hearing loss, including those with enlarged vestibular aqueduct syndrome, showed no significant difference in electrical stimulation threshold with controls. Although some auditory functionality test results were lower in cases than in controls, cochlear implantation appears to be beneficial for all patients with these malformations.

  2. Effect of different lateral occlusion schemes on peri-implant strain: A laboratory study

    Science.gov (United States)

    Lo, Jennifer; Palamara, Joseph

    2017-01-01

    PURPOSE This study aims to investigate the effects of four different lateral occlusion schemes and different excursions on peri-implant strains of a maxillary canine implant. MATERIALS AND METHODS Four metal crowns with different occlusion schemes were attached to an implant in the maxillary canine region of a resin model. The included schemes were canine-guided (CG) occlusion, group function (GF) occlusion, long centric (LC) occlusion, and implant-protected (IP) occlusion. Each crown was loaded in three sites that correspond to maximal intercuspation (MI), 1 mm excursion, and 2 mm excursion. A load of 140 N was applied on each site and was repeated 10 times. The peri-implant strain was recorded by a rosette strain gauge that was attached on the resin model buccal to the implant. For each loading condition, the maximum shear strain value was calculated. RESULTS The different schemes and excursive positions had impact on the peri-implant strains. At MI and 1 mm positions, the GF had the least strains, followed by IP, CG, and LC. At 2 mm, the least strains were associated with GF, followed by CG, LC, and IP. However, regardless of the occlusion scheme, as the excursion increases, a linear increase of peri-implant strains was detected. CONCLUSION The peri-implant strain is susceptible to occlusal factors. The eccentric location appears to be more influential on peri-implant strains than the occlusion scheme. Therefore, adopting an occlusion scheme that can reduce the occurrence of occlusal contacts laterally may be beneficial in reducing peri-implant strains. PMID:28243391

  3. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection.

    Science.gov (United States)

    Golda-Cepa, M; Syrek, K; Brzychczy-Wloch, M; Sulka, G D; Kotarba, A

    2016-09-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function-bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces.

  4. DIY 3D printing of custom orthopaedic implants: a proof of concept study.

    Science.gov (United States)

    Frame, Mark; Leach, William

    2014-03-01

    3D printing is an emerging technology that is primarily used for aiding the design and prototyping of implants. As this technology has evolved it has now become possible to produce functional and definitive implants manufactured using a 3D printing process. This process, however, previously required a large financial investment in complex machinery and professionals skilled in 3D product design. Our pilot study's aim was to design and create a 3D printed custom orthopaedic implant using only freely available consumer hardware and software.

  5. Optimizing paced ventricular function in patients with and without repaired congenital heart disease by contractility-guided lead implant.

    Science.gov (United States)

    Karpawich, Peter P; Singh, Harinder; Zelin, Kathleen

    2015-01-01

    This study evaluates the concept of optimizing ventricular pacing in regard to functional cardiac response. Lead implant based on physiologic variables of contractility at various sites was performed in patients with and without congenital heart disease (CHD). Since right ventricular apical pacing may adversely alter contractility and myocellular function, septal and outflow tract pacing have been advocated. However, there are few studies in the young and essentially none in those with CHD. A total of 113 consecutive patients with and without repaired CHD, aged two to 51 (median 16), some with preexisting epicardial pacemakers, underwent transvenous pacemaker implant using standard sensing/pacing indices plus measurements of pressures, QRS, and contractility responses at each of five predefined potential ventricular implant sites: apex, inflow-, low-, mid-, and infundibular/outflow-septal with each patient serving as his/her own control. Implant was at the site of best contractility with active-fixation, low-threshold steroid-eluting leads. Measured contractility indices varied up to 31% (mean 12%) between sites per patient. Septal regions (mid-, inflow-, and low-) were associated with the most optimal and right ventricular epicardial showed the worst contractility (P implant sites are patient and CHD variable. Current lead designs ensure chronic stability/performance regardless of site. Proactive contractility-guided pacing implant can optimize chronic paced ventricular function. ©2014 Wiley Periodicals, Inc.

  6. The relationship of theory of mind and executive functions in normal, deaf and cochlear-implanted children

    Directory of Open Access Journals (Sweden)

    Farideh Nazarzadeh

    2014-08-01

    Full Text Available Background and Aim : Theory of mind refers to the ability to understand the others have mental states that can be different from one's own mental states or facts. This study aimed to investigate the relationship of theory of mind and executive functions in normal hearing, deaf, and cochlear-implanted children.Methods: The study population consisted of normal, deaf and cochlear-implanted girl students in Mashhad city, Iran. Using random sampling, 30 children (10 normal, 10 deaf and 10 cochlear-implanted in age groups of 8-12 years old were selected. To measure the theoty of mind, theory of mind 38-item scale and to assess executive function, Coolidge neuropsychological and personality test was used. Research data were analyzed using the Spearman correlation coefficient, analysis of variance and Kruskal-Wallis tests.Results: There was a significant difference between the groups in the theory of mind and executive function subscales, organization, planning-decision-making, and inhibition. Between normal and deaf groups (p=0.01, as well as cochlear-implanted and deaf groups (p=0.01, there was significant difference in planning decision-making subscale. There was not any significant relationship between the theory of mind and executive functions generally or the theory of mind and executive function subscales in these three groups independently.Conclusion: Based on our findings, cochlear-implanted and deaf children have lower performance in theory of mind and executive function compared with normal hearing children.

  7. Prognosis of Dental Implants Immediately Placed in Sockets Affected by Peri-implantitis: A Retrospective Pilot Study.

    Science.gov (United States)

    Anitua, Eduardo; Piñas, Laura; Begoña, Leire; Alkhraisat, Mohammad Hamdan

    The aim of this study was to describe a protocol and analyze the outcomes of immediate replacement of failed implants due to peri-implantitis. A total of 17 patients (mean age: 58 ± 10 years) had 22 failed implants that were immediately replaced. One implant failed 16 months after insertion, resulting in an implant survival rate of 94.7%. The mean follow-up time was 40 ± 16 months (range: 9-52 months) after insertion. Mesial and distal bone loss were 0.89 ± 0.62 mm and 0.97 ± 0.66 mm, respectively. Immediate implant replacement could be considered in the management of implant failure due to peri-implantitis.

  8. Mucosal inflammation and incidence of crestal bone loss among implant patients: a 10-year study.

    Science.gov (United States)

    Cecchinato, Denis; Parpaiola, Andrea; Lindhe, Jan

    2014-07-01

    The objective of this prospective study was to determine the prevalence and incidence of marginal bone loss and, in addition, peri-implantitis in subjects and implant sites after 10 years in function. One hundred and thirty-three subjects with a total of 407 implants that had been in function for about 5 years attended a follow-up visit in 2007 (visit 2; V2). 100 of the 133 subjects returned for a new clinical and radiographic examination in 2012 (visit 3; V3). The clinical examination included assessment of "bleeding on probing" (BoP+) and "probing pocket depth." Subjects with implant sites that in the radiograph exhibited crater-shaped marginal bone loss of >0.5 mm were identified as losers. During the interval between V2 and V3 (about 5 years), 13 implants in 7 subjects exhibited progressive bone loss and were removed. The overall amount of crestal bone loss that had occurred at the remaining implants between visit 1 (V1; ≥1 year of loading) and V3 (10 years) was small (0.36 ± 1.4 mm). The bone-level reduction was twice as great between V2 and V3 as between V1 and V2. Forty subjects and 75 (26%) implant sites exhibited marginal bone loss of >0.5 mm between V1 and V3. In the interval between V2 and V3, 37 new implant sites lost significant amounts of bone. During the entire 10-year period (V1-V3), 12% of patients and 5% of implants displayed signs of peri-implantitis (bone loss >0.5 mm, BoP+, PPD ≥6 mm), while in the V2-V3 interval, the corresponding numbers were 10% (patients) and 4% (implant sites). Sites with marginal bone loss of ≥1 mm were not common among implant patients. Peri-implantitis occurred in about 10% of patients and 4% of implant sites. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  9. Studying the Language Development in Children with Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Marjan Sabri leghaie

    1996-04-01

    Full Text Available Cochlear implant surgery is aimed at making a comprehensive packet of information for the deaf by mixing the data acquired by implanted device and the communicational grammar. Although language production and ability of communication are not main factors in determining the candidacy for cochlear implant surgery, they play crucial role in determining cochlear implant success. we should study the communication skills much deeper than a simple perception and production of speech to have a reasonable evaluation of development of Auditory integration and grammatical language structure. Hence in the current article we will first discuss the grammatical structure in language and then have a look at the pragmatics , semantics and phonological aspects in children with cochlear implant in Virginia college in USA.

  10. Peen treatment on a titanium implant: effect of roughness, osteoblast cell functions, and bonding with bone cement

    Directory of Open Access Journals (Sweden)

    Khandaker M

    2016-02-01

    Full Text Available Morshed Khandaker,1,4 Shahram Riahinezhad,1 Fariha Sultana,1 Melville B Vaughan,2,4 Joshua Knight,2 Tracy L Morris3,4 1Department of Engineering & Physics, 2Department of Biology, 3Department of Mathematics and Statistics, 4Center for Interdisciplinary Biomedical Education and Research, University of Central Oklahoma, Edmond, OK, USA Abstract: Implant failure due to poor integration of the implant with the surrounding biomaterial is a common problem in various orthopedic and orthodontic surgeries. Implant fixation mostly depends upon the implant surface topography. Micron to nanosize circular-shaped groove architecture with adequate surface roughness can enhance the mechanical interlock and osseointegration of an implant with the host tissue and solve its poor fixation problem. Such groove architecture can be created on a titanium (Ti alloy implant by laser peening treatment. Laser peening produces deep, residual compressive stresses in the surfaces of metal parts, delivering increased fatigue life and damage tolerance. The scientific novelty of this study is the controlled deposition of circular-shaped rough spot groove using laser peening technique and understanding the effect of the treatment techniques for improving the implant surface properties. The hypothesis of this study was that implant surface grooves created by controlled laser peen treatment can improve the mechanical and biological responses of the implant with the adjoining biomaterial. The objective of this study was to measure how the controlled laser-peened groove architecture on Ti influences its osteoblast cell functions and bonding strength with bone cement. This study determined the surface roughness and morphology of the peen-treated Ti. In addition, this study compared the osteoblast cell functions (adhesion, proliferation, and differentiation between control and peen-treated Ti samples. Finally, this study measured the fracture strength between each kind of Ti samples

  11. Clinical and Radiographic Evaluation of Brånemark Implants with an Anodized Surface following Seven-to-Eight Years of Functional Loading

    Directory of Open Access Journals (Sweden)

    David Gelb

    2013-01-01

    Full Text Available The aim of this study was to evaluate the clinical and radiographic long-term outcomes of dental implants with an anodized TiUnite surface, placed in routine clinical practice. Two clinical centers participated in the study. One hundred and seven implants (80 in the maxilla and 27 in the mandible in 52 patients were followed in the long term. Both one- and two-stage techniques were used for 38 and 69 implants, respectively. Thirty-eight single tooth restorations and 22 fixed partial prostheses were delivered, according to a delayed loading protocol, within 4 to 12 months since implant placement. All implants were stable at insertion and at the long-term follow-up visit, which occurred between 7 and 8 years of functional loading. The mean followup was 7.33±0.47 years. The mean marginal bone level change at the long-term followup as compared to baseline was 1.49±1.03 mm. No implant failure occurred. Healthy peri-implant mucosa was found around 95% of implants, whereas 91% of implants showed no visible plaque at the implant surfaces at the long-term followup. The study showed that dental implants with the TiUnite anodized surface demonstrate excellent long-term clinical and radiographic outcomes.

  12. Revisiting peri-implant soft tissue – histopathological study of the peri-implant soft tissue

    Science.gov (United States)

    Silva, Eduarda; Félix, Sérgio; Rodriguez-Archilla, Alberto; Oliveira, Pedro; Martins dos Santos, José

    2014-01-01

    Peri-implant soft tissues are essential for osseointegration. The peri-implant mucosa may lack vascular supply, and histological observation, even without plaque, shows the presence of inflammatory cells. The objectives of this study were to assess the histopathological changes of the epithelium and connective tissue around the implant. Twenty patients of both genders were studied. Twelve weeks after implant placement, fragments of peri-implant gingival sulcus were harvested and processed for light microscopy. Group I (10): without clinical inflammatory signs (control); Group II (10): with clinical inflammatory signs. Histopathological parameters were analyzed and classified in 3 grades: mild, moderate or severe (grade 1, 2 or 3). Control group showed only slight changes, grade 1. In group II we found edema with moderate to severe cellular and nuclear changes. There are more women than men with all grades of inflammation. All patients with moderate edema are male and all patients with severe edema are female. A significant association (p=0.007) exists between these two variables. Significant differences were found when comparing the degree of inflammation with nuclear alterations (p=0.001) and the same results when comparing the degree of edema and nuclear changes (pimplant mucosa. In clinics the predisposition of female patients to greater degree of edema and inflammation should be accounted for. PMID:24551281

  13. Studies of the quality of the intraosseous dental implant bed and of thermal effects in implant pathology

    Energy Technology Data Exchange (ETDEWEB)

    Wong, K

    2000-07-01

    Dental implants may offer solutions to problems of tooth loss and removable dentures, avoiding the blighting of sound teeth in conventional bridgework. However, there may be severe problems due to deficient and poor quality host bone, particularly in the maxillary sinus region. The success of particulate irradiated mineralised cancellous allograft (IMCA) in generating new bone in the sinus was analysed using the trephine bone cores removed to create an implant bed. Bone cores were embedded and examined using 3D fluorescence fight microscopy and scanning electron microscopy in the backscattered electron (BSE) mode to study the quantity and the quality [degree of mineralisation] of bone in implant sites. In all graft cases, new bone as immature (woven) or mature (lamellar) bone formed on the surfaces of the allograft. The bone volume fraction was found to be significantly greater within 5 mm height of the host sinus floor. In an extended study, control sinuses grafted with IMCA soaked in saline showed no significant difference to the test side treated with the patient's own serum. IMCA was shown to retain much of its original topographical and morphological characteristics. Biopsy core specimens from other (non-sinus) sites in both maxilla and mandible were treated similarly. The highest mineral density distributions were observed in the mandible, with the lowest in the residual posterior maxilla beneath the sinus floor. A novel quantitative bone quality scale is proposed to include three parameters of bone quality: mineralisation density, bone volume fraction and connectivity. Clinical use of Laser Doppler Flowmetry (LDF) confirmed positive blood flow in grafts, sinus membrane, and oral tissues. A model of heat conduction in dental implants, predicted oral heat to be a possible factor in implant pathology. The effect of temperature on avian osteoclastic resorption in vitro was studied using a volumetric pit assay. Osteoclastic function measured as volumes and

  14. Osseointegration of oral implants after delayed placement in rabbits: a microcomputed tomography and histomorphometric study

    NARCIS (Netherlands)

    Anil, S.; Cuijpers, V.M.J.I.; Preethanath, R.S.; Aldosari, A.A.; Jansen, J.A.

    2013-01-01

    Purpose: This study compared osseointegration of implants placed 14 days after implant site preparation with that of immediately placed implants in rabbit femurs. Materials and Methods: Implants were placed bilaterally in the femoral condyles of 12 rabbits. On one side, the implants were placed 14 d

  15. Enhancement of interaction of L-929 cells with functionalized graphene via COOH+ ion implantation vs. chemical method

    Science.gov (United States)

    Zhao, Meng-Li; Liu, Xiao-Qi; Cao, Ye; Li, Xi-Fei; Li, De-Jun; Sun, Xue-Liang; Gu, Han-Qing; Wan, Rong-Xin

    2016-11-01

    Low hydrophilicity of graphene is one of the major obstacles for biomaterials application. To create some hydrophilic groups on graphene is addressed this issue. Herein, COOH+ ion implantation modified graphene (COOH+/graphene) and COOH functionalized graphene were designed by physical ion implantation and chemical methods, respectively. The structure and surface properties of COOH+/graphene and COOH functionalized graphene were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Compared with graphene, COOH+/graphene and COOH functionalized graphene revealed improvement of cytocompatibility, including in vitro cell viability and morphology. More importantly, COOH+/graphene exhibited better improvement effects than functionalized graphene. For instance, COOH+/graphene with 1 × 1018 ions/cm2 showed the best cell-viability, proliferation and stretching. This study demonstrated that ion implantation can better improve the cytocompatibility of the graphene.

  16. Neurotherapeutic and neuroprosthetic effects of implanted functional electrical stimulation for ambulation after incomplete spinal cord injury.

    Science.gov (United States)

    Bailey, Stephanie Nogan; Hardin, Elizabeth C; Kobetic, Rudi; Boggs, Lisa M; Pinault, Gilles; Triolo, Ronald J

    2010-01-01

    The purpose of this single-subject study was to determine the neurotherapeutic and neuroprosthetic effects of an implanted functional electrical stimulation (FES) system designed to facilitate walking in an individual with a longstanding motor and sensory incomplete spinal cord injury. An implanted pulse generator and eight intramuscular stimulating electrodes were installed unilaterally, activating weak or paralyzed hip flexors, hip and knee extensors, and ankle dorsiflexors during 36 sessions of gait training with FES. The neurotherapeutic effects were assessed by a comparison of pre- and posttraining volitional walking. The neuroprosthetic effects were assessed by a comparison of posttraining volitional and FES-assisted walking. Treatment resulted in significant (p ambulation to limited community ambulation. Additionally, the subject could perform multiple walks per day when using FES-assisted gait, which was impossible with volitional effort alone.

  17. XANES study of Fe-implanted strontium titanate

    Science.gov (United States)

    Lobacheva, O.; Goncharova, L. V.; Chavarha, M.; Sham, T. K.

    2014-03-01

    Properties of strontium titanate SrTiO3 (STO) depend to a great extent on the substitutional dopants and defects of crystal structure. The ion beam implantation method was used for doping STO (001) crystals with Fe at different doses. Implanted samples were then annealed at 350°C in oxygen to induce recrystallization and remove oxygen vacancies produced during ion implantation process. The effect of Fe doping and post-implantation annealing was studied by X-ray Absorption Near Edge Spectroscopy (XANES) method and Superconducting Quantum Interference Device (SQUID). XANES allowed to monitor the change in structure of STO crystals and in the local environment of Fe following the implantation and annealing steps. SQUID measurements revealed correlation between magnetic moment and Fe implantation dose. Ferromagnetic hysteresis was observed on selected Fe-implanted STO at 5 K. The observed magnetic properties can be correlated with the several Fe oxide phases in addition to the presence of O/Ti vacancies.

  18. [Implant-borne prosthetic rehabilitation in patients with cleft lip and palate: A retrospective study on 43 patients].

    Science.gov (United States)

    Borgnat, F; Martin, P; Paulus, C

    2015-09-01

    Implant-borne rehabilitation in cleft lip and palate patient are aimed to allow for good orofacial functions, stable occlusion, and adequate support for the naso-labial region. The goal of our study was to evaluate the functional and esthetic results of the implant-born dental rehabilitation of the cleft lip and palate patients in our department. Our retrospective study concerned patients operated between 1995 and 2010 in our department. All included patients suffered from a cleft alveolus and lip, with or without cleft palate. Dental implants were placed in the bone-grafted alveolus and the end of growth and at distance from the bone graft procedure. Criteria of implant survival and implant-borne rehabilitation success were defined. A total of 78 implants were placed in 43 patients between 1995 and 2010. Two implants were lost (implant survival rate: 97.4%). Despite this loss, all the patients could be rehabilitated with good functional and esthetic results. Implant-borne rehabilitation is a reliable solution for prosthetic rehabilitation in patients with cleft lip and palate. This solution allows for avoiding removable prosthesis and dental mutilation. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  19. Design optimization of a radial functionally graded dental implant.

    Science.gov (United States)

    Ichim, Paul I; Hu, Xiaozhi; Bazen, Jennifer J; Yi, Wei

    2016-01-01

    In this work, we use FEA to test the hypothesis that a low-modulus coating of a cylindrical zirconia dental implant would reduce the stresses in the peri-implant bone and we use design optimization and the rule of mixture to estimate the elastic modulus and the porosity of the coating that provides optimal stress shielding. We show that a low-modulus coating of a dental implant significantly reduces the maximum stresses in the peri-implant bone without affecting the average stresses thus creating a potentially favorable biomechanical environment. Our results suggest that a resilient coating is capable of reducing the maximum compressive and tensile stresses in the peri-implant bone by up to 50% and the average stresses in the peri-implant bone by up to 15%. We further show that a transitional gradient between the high-modulus core and the low-modulus coating is not necessary and for a considered zirconia/HA composite the optimal thickness of the coating is 100 µ with its optimal elastic at the lowest value considered of 45 GPa. © 2015 Wiley Periodicals, Inc.

  20. The combined effects of undersized drilling and implant macrogeometry on bone healing around dental implants: an experimental study.

    Science.gov (United States)

    Jimbo, R; Tovar, N; Anchieta, R B; Machado, L S; Marin, C; Teixeira, H S; Coelho, P G

    2014-10-01

    This study investigated the effect of undersized preparations with two different implant macrogeometries. There were four experimental groups: group 1, conical implant with an undersized osteotomy of 3.2mm; group 2, conical implant with an undersized osteotomy of 3.5mm; group 3, cylindrical implant with an undersized osteotomy of 3.2mm; group 4, cylindrical implant with an undersized osteotomy of 3.5mm. Implants were placed in one side of the sheep mandible (n=6). After 3 weeks, the same procedure was conducted on the other side; 3 weeks later, euthanasia was performed. All implants were 4mm×10mm. Insertion torque was recorded for all implants during implantation. Retrieved samples were subjected to histological sectioning and histomorphometry. Implants of groups 1 and 2 presented significantly higher insertion torque than those of groups 3 and 4 (Pimplant contact or bone area fraction occupied were observed between the groups at 3 weeks (P>0.24, and P>0.25, respectively), whereas significant differences were observed at 6 weeks between groups 1 and 2, and between groups 3 and 4 (Pdental implant macrogeometries.

  1. Spontaneous progression of ligature induced peri-implantitis at implants with different surface roughness: an experimental study in dogs.

    Science.gov (United States)

    Berglundh, T; Gotfredsen, K; Zitzmann, N U; Lang, N P; Lindhe, J

    2007-10-01

    Peri-implantitis is associated with the presence of submarginal plaque, soft-tissue inflammation and advanced breakdown of the supporting bone. The progression of peri-implantitis following varying periods of continuing plaque accumulation has been studied in animal models. The aim of the current experiment was to study the progression of peri-implantitis around implants with different surface roughness. In five beagle dogs, three implants with either a sandblasted acid-etched surface (SLA) or a polished surface (P) were installed bilaterally in the edentulous premolar regions. After 3 months on a plaque control regimen, experimental peri-implantitis was induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. After this 4-month period, ligatures were removed and plaque accumulation was continued for an additional 5 months. Radiographs of all implant sites were obtained before and after 'active' experimental peri-implantitis as well as at the end of the experiment. Biopsies were harvested and the tissue samples were prepared for light microscopy. The sections were used for histometric and morphometric examinations. The radiographic examinations indicated that similar amounts of bone loss occurred at SLA and P sites during the active breakdown period, while the progression of bone loss was larger at SLA than at polished sites following ligature removal. The histological examination revealed that both bone loss and the size of the inflammatory lesion in the connective tissue were larger in SLA than in polished implant sites. The area of plaque was also larger at implants with an SLA surface than at implants with a polished surface. It is suggested that the progression of peri-implantitis, if left untreated, is more pronounced at implants with a moderately rough surface than at implants with a polished surface.

  2. Implant survival and patient satisfaction of reduced diameter implants made from a titanium-zirconium alloy: A retrospective cohort study with 550 implants in 311 patients.

    Science.gov (United States)

    Herrmann, Jan; Hentschel, Andreas; Glauche, Ingmar; Vollmer, Armin; Schlegel, Karl Andreas; Lutz, Rainer

    2016-12-01

    The aim of the study was to evaluate implant survival of reduced-diameter implants compared to regular-diameter implants. A retrospective evaluation of 154 Straumann Bone Level Roxolid(®) implants (diameter 3.3 mm) with SLActive(®)-surface in 107 patients, which were inserted between 2009 and 2010 in private practice, was performed. The mean observation period was 22.4 ± 8.2 months. 396 Straumann SLActive(®) implants (4.1 mm and 4.8 mm) in 204 patients, with an observation period of 28.4 ± 10.1 months served as control group. Implant survival rate, resonance frequency analysis and patient satisfaction were evaluated. The implant survival rate was 97.4% in the test vs. 98.5% in the control group. Resonance frequency analysis showed statistically significant lower values for the reduced-diameter implants. Patient satisfaction showed no significant difference between the test and the control group. Reduced-diameter implants displayed high survival rates during the period investigated and represent a convincing treatment alternative. Long-term follow-up investigations confirmed the high implant survival rates of 96.8% (after 69.7 ± 12.3 months) in the test group and 98.5% (after 76.0 ± 13.6 months) in the control group.

  3. Long-term retrospective study of implants placed after sinus floor augmentation with fresh-frozen homologous block

    Directory of Open Access Journals (Sweden)

    Livingstom Rubens Sousa Rocha

    2017-01-01

    Full Text Available Aim: The aim of this study was to analyze and follow-up implants placed in the posterior maxillary regions previously grafted with homologous bone. Materials and Methods: Forty-one grafts with homologous bone blocks were performed in maxillary sinuses, and 121 implants were placed in premolar and molar regions approximately 6 months after the grafts. Patients were followed up for periods varying from 12 to 124 months after rehabilitation. Results: The results showed two implant failures, for a 98.3% success rate during the follow-up period. Discussion: The implants placed had an average torque of 40 N-cm, regardless of the, design, diameter, and length of the implants used. Conclusion: After following up on the implants placed in this study, we concluded that those placed in regions of the maxillary sinuses previously grafted with homologous bone blocks had high long-term success rates and met the functional masticatory requirements.

  4. [Advances in the study of virtual channels of cochlear implant].

    Science.gov (United States)

    Zhu, Ziyan; Guan, Tian; Ye, Datian

    2009-12-01

    This paper discusses virtual channels of cochlear implant, which is produced by simultaneous or sequential activation of adjacent cochlear implant electrodes. Virtual channels create and transfer more available spectral pitch information with the limited number of fixed electrodes, which can be recognized as pitch percepts intermediate to those produced by each electrode separately. This technique not only utilizes the interaction of electrodes but also increases the number of place-pitch steps available to cochlear implant listeners. Virtual channels could be used to realize speech recognition in noisy environment, in enjoying music, and in understanding Chinese language. The study of virtual channels would significantly enhance the traditional cochlear implant therapy and benefit people suffering severe to profound hearing loss.

  5. Implant stability and marginal bone level of microgrooved zirconia dental implants: A 3-month experimental study on dogs

    Directory of Open Access Journals (Sweden)

    Delgado-Ruíz Rafael Arcesio

    2014-01-01

    Full Text Available Background/Aim. The modification of implant surfaces could affect mechanical implant stability as well as dynamics and quality of peri-implant bone healing. The aim of this 3-month experimental study in dogs was to investigate implant stability, marginal bone levels and bone tissue response to zirconia dental implants with two laser-micro-grooved intraosseous surfaces in comparison with nongrooved sandblasted zirconia and sandblasted, high-temperature etched titanium implants. Methods. Implant surface characterization was performed using optical interferometric profilometry and energy dispersive X-ray spectroscopy. A total of 96 implants (4 mm in diameter and 10 mm in length were inserted randomly in both sides of the lower jaw of 12 Fox Hound dogs divided into groups of 24 each: the control (titanium, the group A (sandblasted zirconia, the group B (sandblasted zirconia plus microgrooved neck and the group C (sandblasted zirconia plus all microgrooved. All the implants were immediately loaded. Insertion torque, periotest values, radiographic crestal bone level and removal torque were recorded during the 3-month follow-up. Qualitative scanning electon micro-scope (SEM analysis of the bone-implant interfaces of each group was performed. Results. Insertion torque values were higher in the group C and control implants (p the control > the group B > the group A (p the control > the group B > the group A (p < 0.05. SEM showed that implant surfaces of the groups B and C had an extra bone growth inside the microgrooves that corresponded to the shape and direction of the microgrooves. Conclusion. The addition of micro-grooves to the entire intraosseous surface of zirconia dental implants enhances primary and secondary implant stability, promotes bone tissue ingrowth and preserves crestal bone levels.

  6. Sensory innervation around immediately vs. delayed loaded implants:a pilot study

    Institute of Scientific and Technical Information of China (English)

    Yan Huang; Jeroen van Dessel; Wendy Martens; Ivo Lambrichts; Wei-Jian Zhong; Guo-Wu Ma; Dan Lin; Xin Liang; Reinhilde Jacobs

    2015-01-01

    Although neurophysiological and psychophysical proof of osseoperception is accumulating, histomorphometric evidence for the neural mechanisms of functional compensation following immediate and delayed implant loading is still lacking. For this randomized split-mouth study, six mongrel dogs randomly received one of four treatment protocols at 36 implant-recipient sites over 16 weeks (third maxillary incisor, third and fourth mandibular premolar):immediate implant placement and immediate loading (IIP1IL);delayed implant placement and delayed loading (DIP1DL);delayed implant placement and immediate loading (DIP1IL);and natural extraction socket healing (control). Histomorphometry was performed in the peri-implant bone and soft tissues within 300 mm around the implants. Immunocytochemistry and transmission electron microscopy were used to confirm the presence of neural structures and to reveal their ultrastructural characteristics, respectively. Myelinated nerve fibres densely populated the peri-implant crestal gingival and apical regions, although they were also identified in the woven bone and in the osteons near the implant threads. Compared with the control group in the mandible, the group that received IIP1IL showed a higher innervation (in N?mm22, 5.9461.12 vs. 3.1560.63, P,0.001) and smaller fibre diameter (in mm, 1.3760.05 vs. 1.6460.13, P50.016), smaller axon diameter (in mm, 0.8960.05 vs. 1.2460.10, P50.009) and g-ratio (0.6460.04 vs. 0.7660.05, P,0.001) in the middle region around the implants. Compared with DIP1IL in the mandible, IIP1IL had a higher nerve density (in N?mm22, 13.2362.54 vs. 9.6461.86, P50.027), greater fibre diameter (in mm, 1.3260.02 vs. 1.2060.04, P50.021), greater axon diameter (in mm, 0.9260.01 vs. 0.8960.03, P50.035) and lower g-ratio (0.6960.01 vs. 0.7460.01, P50.033) in the apical region around the implants. It may be assumed that the treatment protocol with IIP1IL is the preferred method to allow optimized peri-implant re

  7. Implant-supported single-tooth restorations. A 12-year prospective study.

    Science.gov (United States)

    Donati, Mauro; Ekestubbe, Annika; Lindhe, Jan; Wennström, Jan L

    2016-10-01

    The aim of this study was to evaluate prospectively the 12-year outcome of implant-supported single-tooth restorations. Originally 45 self-tapping Astra Tech TiOblast(®) ST-implants were installed by a two-stage protocol in 40 subjects requiring single-tooth prosthetic replacement for a missing tooth. Clinical and radiologic examinations were performed at completion of the prosthetic treatment 4-7 months after implant installation surgery and after 5 and 12 years in function. At 12 years 31 patients and 35 implants were available for evaluation. The overall failure rate after 12 years was 10.3% on the subject level and 9.1% on the implant level. The mean bone loss amounted to 0.67 mm (SD 2.20) on a subject level and 0.47 mm (1.72) on an implant level. Three subjects (10%) and three implants (8.6%) were diagnosed with peri-implantitis. Five subjects had experienced technical complications; three incidences of loosening of the abutment retention screw during the first 5 years and two minor porcelain fracture of the crown (two patients) between 5- and 12-years of follow-up. The findings reported in this 12-year prospective case series suggest that the use of the Astra Tech dental implants may be a valid treatment alternative for single-tooth replacement prostheses. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Microrobotized blasting improves the bone-to-textured implant response. A preclinical in vivo biomechanical study.

    Science.gov (United States)

    Coelho, Paulo G; Gil, Luiz F; Neiva, Rodrigo; Jimbo, Ryo; Tovar, Nick; Lilin, Thomas; Bonfante, Estevam A

    2016-03-01

    This study evaluated the effect of microrobotized blasting of titanium endosteal implants relative to their manually blasted counterparts. Two different implant systems were utilized presenting two different implant surfaces. Control surfaces (Manual) were fabricated by manually grit blasting the implant surfaces while experimental surfaces (Microblasted) were fabricated through a microrobotized system that provided a one pass grit blasting routine. Both surfaces were created with the same ~50µm average particle size alumina powder at ~310KPa. Surfaces were then etched with 37% HCl for 20min, washed, and packaged through standard industry procedures. The surfaces were characterized through scanning electron microscopy (SEM) and optical interferometry, and were then placed in a beagle dog radius model remaining in vivo for 3 and 6 weeks. The implant removal torque was recorded and statistical analysis evaluated implant system and surface type torque levels as a function of time in vivo. Histologic sections were qualitatively evaluated for tissue response. Electron microscopy depicted textured surfaces for both manual and microblasted surfaces. Optical interferometry showed significantly higher Sa, Sq, values for the microblasted surface and no significant difference for Sds and Sdr values between surfaces. In vivo results depicted that statistically significant gains in biomechanical fixation were obtained for both implant systems tested at 6 weeks in vivo, while only one system presented significant biomechanical gain at 3 weeks. Histologic sections showed qualitative higher amounts of new bone forming around microblasted implants relative to the manually blasted group. Microrobotized blasting resulted in higher biomechanical fixation of endosteal dental implants and should be considered as an alternative for impant surface manufacturing.

  9. [Experimental study of osseointegration of zirconium and titanium dental implants].

    Science.gov (United States)

    Kulakov, O B; Doktorov, A A; D'iakova, S V; Denisov-Nikol'skiĭ, Iu I; Grötz, K A

    2005-01-01

    In an experiment performed on pigs, methods of light and scanning electron microscopy were used to study the interaction of zirconium and titanium dental implants with bone 6 months following their insertion. Distinct features of integration of both implant types with bone structures were detected. Sites of direct contact of bone structures with metal were found to undergo constant remodeling according to biochemical and metabolic conditions in each zone of an implant surface. Statistically the degree of interactive properties of zirconium implants significantly exceeded similar parameter for titanium screws. Along the perimeter of the zones of bone contact with zirconium implants greater numbers of forming and formed bone areas were revealed as compared to the zones of bone contact with titanium implants, where erosion lacunae were more numerous. The complex of research methods used in this study have not revealed distinct changes in the structure of osteocytes, located in immediate proximity to the metal surface in comparison with more distant sites in the bone.

  10. The efficacy of flapless implant surgery on soft-tissue profile comparing immediate loading implants to delayed loading implants: A comparative clinical study

    Directory of Open Access Journals (Sweden)

    Ravindran Deepak

    2010-01-01

    Full Text Available Aims and Objectives : To assess the efficacy of flapless implant surgery on soft-tissue profile and to compare the clinical outcomes of flapless implant therapy on immediate loading (IL implants to delayed loading (DL implants. Materials and Methods : The study sample consisted of 20 patients who were partially edentulous in the anterior maxillary region. They were divided into two groups. In group I (IL 10 implants were placed and immediately provisionalized and restored with a metal ceramic crown on the 14th day. In group II (DL 10 implants were placed and loaded after 4 months. Single-piece implants were used for the IL group and two-piece implants were used for the DL group. All soft tissue parameters i.e., modified plaque index (mPI, modified bleeding index (mBI, papillary index (PPI, marginal level of soft tissue (ML and width of keratinized mucosa (WKM were recorded at baseline, Day 60, Day 120 and Day 180. Results: The success rate in group I was found to be 80%, which was lower than the success rate in group II which was found to be 90%. On comparison, there is no statistically significant difference in success rate between the two study groups. There was no statistically significant difference between the groups over time in parameters like mPI, mBI, ML and WKM. The mean PPI score in group II showed a significant increase from when compared to group I. Conclusion: The results of this study indicated that flapless implant surgery using either immediately loading implants or DL implants, demonstrate enhancement of implant esthetics.

  11. Use of the International Classification of Functioning, Disability and Health for monitoring patients using cochlear implants.

    Science.gov (United States)

    Morettin, Marina; Cardoso, Maria Regina Alves; Delamura, Aline Malavasi; Zabeu, Julia Speranza; Amantini, Regina Célia Bortoleto; Bevilacqua, Maria Cecília

    2013-01-01

    To characterize the profile of patients with cochlear implant as proposed by the International Classification of Functioning, Disability and Health for Children and Youth (ICF-CY). This is a descriptive, cross-sectional retrospective study, which examined 30 medical records of patients using the cochlear implant of Centro de Pesquisas Audiológicas; To characterize the profile of the patients, the ICF-CY was used. Regarding the assessment, researchers relied on procedures performed in clinical routine, besides information registered in the medical record. After reviewing the information, it was related to codes from the ICF-CY; with the addition of a qualifier afterwards. Overall, 55 codes from the ICF were related to the instruments to characterize this population. Regarding the Body Functions field, most participants did not have disabilities related to reception and expression of oral language and auditory functions, with only written language disabilities being found. These same findings were observed in the Activity and Participation Field. Regarding environmental factors, noise and the non-availability of technology resources to assist in the auditory comprehension of noise were characterized as a barrier, as well as the absence of speech therapy. This study concluded that most of the participating children showed no deficiency in the body functions, with difficulties being only reported in relation to school performance. Environmental factors (noise, non-availability of technological resources, absence of speech therapy) were characterized as a barrier. The need to expand assessments in the clinical routine was also noted.

  12. In vitro study of magnetic nanoparticles as the implant for implant assisted magnetic drug targeting

    Energy Technology Data Exchange (ETDEWEB)

    Mangual, Jan O.; Aviles, Misael O.; Ebner, Armin D. [Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States); Ritter, James A., E-mail: ritter@cec.sc.ed [Department of Chemical Engineering, University of South Carolina, Columbia, SC 29208 (United States)

    2011-07-15

    Magnetic nanoparticle (MNP) seeds were studied in vitro for use as an implant in implant assisted-magnetic drug targeting (IA-MDT). The magnetite seeds were captured in a porous polymer, mimicking capillary tissue, with an external magnetic field (70 mT) and then used subsequently to capture magnetic drug carrier particles (MDCPs) (0.87 {mu}m diameter) with the same magnetic field. The effects of the MNP seed diameter (10, 50 and 100 nm), MNP seed concentration (0.25-2.0 mg/mL), and fluid velocity (0.03-0.15 cm/s) on the capture efficiency (CE) of both the MNP seeds and the MDCPs were studied. The CE of the 10 nm MNP seeds was never more than 30%, while those of the 50 and 100 nm MNP seeds was always greater than 80% and in many cases exceeded 90%. Only the MNP seed concentration affected its CE. The 10 nm MNP seeds did not increase the MDCP CE over that obtained in the absence of the MNP seeds, while the 50 and 100 nm MNP seeds increased significantly, typically by more than a factor of two. The 50 and 100 nm MNP seeds also exhibited similar abilities to capture the MDCPs, with the MDCP CE always increasing with decreasing fluid velocity and generally increasing with increasing MNP seed concentration. The MNP seed size, magnetic properties, and capacity to self-agglomerate and form clusters were key properties that make them a viable implant in IA-MDT. - Highlights: 50-100 nm magnetite nanoparticles can be retained in a porous scaffold using a 70 mT field. Their presence improves the collection efficiency of 0.87 {mu}m magnetic drug carrier particles. Magnetic nanoparticles can thus be used as the implant in implant assisted-magnetic drug targeting.

  13. Biomechanical and histologic basis of osseodensification drilling for endosteal implant placement in low density bone. An experimental study in sheep.

    Science.gov (United States)

    Lahens, Bradley; Neiva, Rodrigo; Tovar, Nick; Alifarag, Adham M; Jimbo, Ryo; Bonfante, Estevam A; Bowers, Michelle M; Cuppini, Marla; Freitas, Helora; Witek, Lukasz; Coelho, Paulo G

    2016-10-01

    A bone drilling concept, namely osseodensification, has been introduced for the placement of endosteal implants to increase primary stability through densification of the osteotomy walls. This study investigated the effect of osseodensification on the initial stability and early osseointegration of conical and parallel walled endosteal implants in low density bone. Five male sheep were used. Three implants were inserted in the ilium, bilaterally, totaling 30 implants (n=15 conical, and n=15 parallel). Each animal received 3 implants of each type, inserted into bone sites prepared as follows: (i) regular-drilling (R: 2mm pilot, 3.2mm, and 3.8mm twist drills), (ii) clockwise osseodensification (CW), and (iii) counterclockwise (CCW) osseodensification drilling with Densah Bur (Versah, Jackson, MI, USA): 2.0mm pilot, 2.8mm, and 3.8mm multi-fluted burs. Insertion torque as a function of implant type and drilling technique, revealed higher values for osseodensification relative to R-drilling, regardless of implant macrogeometry. A significantly higher bone-to-implant contact (BIC) for both osseodensification techniques (pdrilling. There was no statistical difference in BIC as a function of implant type (p=0.58), nor in bone-area-fraction occupancy (BAFO) as a function of drilling technique (p=0.22), but there were higher levels of BAFO for parallel than conic implants (p=0.001). Six weeks after surgery, new bone formation along with remodeling sites was observed for all groups. Bone chips in proximity with the implants were seldom observed in the R-drilling group, but commonly observed in the CW, and more frequently under the CCW osseodensification technique. In low-density bone, endosteal implants present higher insertion torque levels when placed in osseodensification drilling sites, with no osseointegration impairment compared to standard subtractive drilling methods.

  14. Implant-supported overdentures, a prevention of bone loss in edentulous mandibles? A 5-year follow-up study

    DEFF Research Database (Denmark)

    von Wowern, N; Gotfredsen, K

    2001-01-01

    the implants and 3) whether the presence of mandibular osteoporosis affects the loss of bone height around the implants. The material consisted of 22 long-term edentulous healthy persons, 18 women and 4 men from 54 to 78 years of age with 1 Astra Tech Dental Implant in both canine regions, connected by a bar......The purpose of this study were to analyse 1) the changes in the bone mineral content (BMC) in mandibles with implant-supported overdentures when compared with the physiologic age-related mandibular BMC loss, 2) whether the BMC changes were different in groups without or with a bar connecting...... of bone height around implants was measured on periodically identical intraoral radiographs. The fixed parts of the implant-system were stable during the trial in all patients. In conclusion: 1) the increased function after this treatment seems to cause a load-related bone formation which minimizes...

  15. Primary role of electron work function for evaluation of nanostructured titania implant surface against bacterial infection

    Energy Technology Data Exchange (ETDEWEB)

    Golda-Cepa, M., E-mail: golda@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Syrek, K. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Brzychczy-Wloch, M. [Department of Bacteriology, Microbial Ecology and Parasitology, Jagiellonian University Medical College, Czysta 18, 31-121 Krakow (Poland); Sulka, G.D. [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland); Kotarba, A., E-mail: kotarba@chemia.uj.edu.pl [Faculty of Chemistry, Jagiellonian University, Ingardena 3, 30-060 Krakow (Poland)

    2016-09-01

    The electron work function as an essential descriptor for the evaluation of metal implant surfaces against bacterial infection is identified for the first time. Its validity is demonstrated on Staphylococcus aureus adhesion to nanostructured titania surfaces. The established correlation: work function–bacteria adhesion is of general importance since it can be used for direct evaluation of any electrically conductive implant surfaces. - Highlights: • The correlation between work function and bacteria adhesion was discovered. • The discovered correlation is rationalized in terms of electrostatic bacteria–surface repulsion. • The results provide basis for the simple evaluation of implant surfaces against infection.

  16. Development of language and speech perception in congenitally, profoundly deaf children as a function of age at cochlear implantation.

    Science.gov (United States)

    Svirsky, Mario A; Teoh, Su-Wooi; Neuburger, Heidi

    2004-01-01

    Like any other surgery requiring anesthesia, cochlear implantation in the first few years of life carries potential risks, which makes it important to assess the potential benefits. This study introduces a new method to assess the effect of age at implantation on cochlear implant outcomes: developmental trajectory analysis (DTA). DTA compares curves representing change in an outcome measure over time (i.e. developmental trajectories) for two groups of children that differ along a potentially important independent variable (e.g. age at intervention). This method was used to compare language development and speech perception outcomes in children who received cochlear implants in the second, third or fourth year of life. Within this range of age at implantation, it was found that implantation before the age of 2 resulted in speech perception and language advantages that were significant both from a statistical and a practical point of view. Additionally, the present results are consistent with the existence of a 'sensitive period' for language development, a gradual decline in language acquisition skills as a function of age. Copyright 2004 S. Karger AG, Basel

  17. Spontaneous progression of ligature induced peri-implantitis at implants with different surface roughness: an experimental study in dogs

    DEFF Research Database (Denmark)

    Berglundh, T; Gotfredsen, K; Zitzmann, N U

    2007-01-01

    BACKGROUND: Peri-implantitis is associated with the presence of submarginal plaque, soft-tissue inflammation and advanced breakdown of the supporting bone. The progression of peri-implantitis following varying periods of continuing plaque accumulation has been studied in animal models. OBJECTIVE......: The aim of the current experiment was to study the progression of peri-implantitis around implants with different surface roughness. MATERIAL AND METHODS: In five beagle dogs, three implants with either a sandblasted acid-etched surface (SLA) or a polished surface (P) were installed bilaterally...... in the edentulous premolar regions. After 3 months on a plaque control regimen, experimental peri-implantitis was induced by ligature placement and plaque accumulation was allowed to progress until about 40% of the height of the supporting bone had been lost. After this 4-month period, ligatures were removed...

  18. Brazilian adaptation of the Functioning after Pediatric Cochlear Implantation (FAPCI: comparison between normal hearing and cochlear implanted children

    Directory of Open Access Journals (Sweden)

    Trissia M.F. Vassoler

    2015-04-01

    Full Text Available OBJECTIVE: Enabling development of the ability to communicate effectively is the principal objective of cochlear implantation (CI in children. However, objective and effective metrics of communication for cochlear-implanted Brazilian children are lacking . The Functioning after Pediatric Cochlear Implantation (FAPCI, a parent/caregiver reporting instrument developed in the United States, is the first communicative performance scale for evaluation of real-world verbal communicative performance of 2-5-year-old children with cochlear implants. The primary aim was to cross-culturally adapt and validate the Brazilian-Portuguese version of the FAPCI. The secondary aim was to conduct a trial of the adapted Brazilian-Portuguese FAPCI (FAPCI-BP in normal hearing (NH and CI children. METHODS: The American-English FAPCI was translated by a rigorous forward-backward process. The FAPCI-BP was then applied to the parents of children with NH (n = 131 and CI (n = 13, 2-9 years of age. Test-retest reliability was verified. RESULTS: The FAPCI-BP was confirmed to have excellent internal consistency (Cronbach's alpha > 0.90. The CI group had lower FAPCI scores (58.38 ± 22.6 than the NH group (100.38 ± 15.2; p < 0.001, Wilcoxon test. CONCLUSION: The present results indicate that the FAPCI-BP is a reliable instrument. It can be used to evaluate verbal communicative performance in children with and without CI. The FAPCI is currently the only psychometrically-validated instrument that allows such measures in cochlear-implanted children.

  19. Impact and evolution of right ventricular dysfunction after successful MitraClip implantation in patients with functional mitral regurgitation

    Directory of Open Access Journals (Sweden)

    Cosmo Godino

    2016-06-01

    Conclusions: This study shows that successful MitraClip implantation in patients with FMR and concomitant right ventricular dysfunction yields significant improvement of RV function at mid-term follow-up. Further data on larger population will be required to confirm our observations.

  20. Psychological Functioning and Disease-Related Quality of Life in Pediatric Patients With an Implantable Cardioverter Defibrillator

    NARCIS (Netherlands)

    Koopman, H. M.; Vrijmoet-Wiersma, C. M. J.; Langius, J. N. D.; van den Heuvel, F.; Clur, S. A.; Blank, C. A.; Blom, N. A.; ten Harkel, A. D. J.

    2012-01-01

    The objective of this multicenter study was to evaluate psychological functioning and disease-related quality of life (DRQoL) in pediatric patients with an implantable cardioverter defibrillator (ICD) in The Netherlands. Thirty patients were investigated; the mean age was 16.3 years, and the mean du

  1. Assessment of trabecular bone changes around endosseous implants using image analysis techniques: A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Zuki, Mervet El [Dept. of Oral Medicine and Radiology, Benghazi University College of Dentistry, Benghazi (Libya); Omami, Galal [Oral Diagnosis and Polyclinics, Faculty of Dentistry, The University of Hong Kong (Hong Kong); Horner, Keith [Dept. of Oral Radiology, University Dental Hospital of Manchester, Manchester (United Kingdom)

    2014-06-15

    The objective of this study was to assess the trabecular bone changes that occurred around functional endosseous dental implants by means of radiographic image analysis techniques. Immediate preoperative and postoperative periapical radiographs of de-identified implant patients at the University Dental Hospital of Manchester were retrieved, screened for specific inclusion criteria, digitized, and quantified for structural elements of the trabecular bone around the endosseous implants, by using image analysis techniques. Data were analyzed using SPSS version 11.5. P values of less than 0.05 were considered statistically significant. A total of 12 implants from 11 patients were selected for the study, and 26 regions of interest were obtained. There was a significant increase in the bone area in terms of the mean distance between nodes (p=0.006) and a significant decrease in the marrow area in terms of the bone area (p=0.006) and the length of marrow spaces (p=0.032). It appeared that the bone around the implant underwent remodeling that resulted in a net increase in bone after implant placement.

  2. Optimum gradient material for a functionally graded dental implant using metaheuristic algorithms.

    Science.gov (United States)

    Sadollah, Ali; Bahreininejad, Ardeshir

    2011-10-01

    Despite dental implantation being a great success, one of the key issues facing it is a mismatch of mechanical properties between engineered and native biomaterials, which makes osseointegration and bone remodeling problematical. Functionally graded material (FGM) has been proposed as a potential upgrade to some conventional implant materials such as titanium for selection in prosthetic dentistry. The idea of an FGM dental implant is that the property would vary in a certain pattern to match the biomechanical characteristics required at different regions in the hosting bone. However, matching the properties does not necessarily guarantee the best osseointegration and bone remodeling. Little existing research has been reported on developing an optimal design of an FGM dental implant for promoting long-term success. Based upon remodeling results, metaheuristic algorithms such as the genetic algorithms (GAs) and simulated annealing (SA) have been adopted to develop a multi-objective optimal design for FGM implantation design. The results are compared with those in literature.

  3. Optimal restoration of dental esthetics and function with advanced implant-supported prostheses: a clinical report.

    Science.gov (United States)

    Meulen, Peter van der; Linden, Wynand van der; Eeden, Ronnie van

    2012-07-01

    For more than 25 years, computer-aided design and computer-aided manufacturing (CAD/CAM) technology has been used in implant restorative dentistry. Today this technology offers a means of milling titanium frameworks that fit dental implants accurately. This report presents a restoratively driven protocol employing advanced implant restorative and surgical techniques. Treatment of a patient with advanced periodontitis with extensive loss of hard and soft tissues is presented. After extraction of the patient's remaining hopeless teeth, dental implants were placed, along with interim, fixed-margin abutments and abutment protection caps. Two days later, acrylic resin fixed-interim prostheses restored the patient's esthetics and partial masticatory function. After implant osseointegration, maxillary, and mandibular frameworks for definitive prostheses were milled from Ti alloy, using one specific CAD/CAM technology. The benefits of this technology are also discussed.

  4. Bone level change at implant-supported fixed partial dentures with and without cantilever extension after 5 years in function.

    Science.gov (United States)

    Wennström, Jan; Zurdo, Jose; Karlsson, Stig; Ekestubbe, Annika; Gröndahl, Kerstin; Lindhe, Jan

    2004-12-01

    The aim of this study was to retrospectively analyze whether the inclusion of cantilever extensions increased the amount of marginal bone loss at free-standing, implant-supported, fixed partial dentures (FPDs) over a 5-year period of functional loading. The patient material comprised 45 periodontally treated, partially dentate patients with a total of 50 free-standing FPDs supported by implants of the Astra Tech System. Following FPD placement (baseline) the patients were enrolled in an individually designed supportive care program. A set of criteria was collected at baseline to characterize the FPDs. The primary outcome variable was change in peri-implant bone level from the time of FPD placement to the 5-year follow-up examination. The comparison between FPDs with and without cantilevers was performed at three levels: FPD level, implant level, and surface level. Bivariate analysis was performed by the use of the Mann-Whitney U-test and stepwise regression analysis was utilized to evaluate the potential influence of confounding factors on the change in peri-implant bone level. The overall mean marginal bone loss for the implant-supported FPDs after 5 years in function was 0.4 mm (SD, 0.76). The bone level change at FPDs placed in the maxilla was significantly greater than that for FPDs in the mandible (0.6 versus 0.2 mm; p<0.05). No statistically significant differences were found with regard to peri-implant bone level change over the 5 years between FPDs with and without cantilevers at any of the levels of comparisons. The multivariate analysis revealed that the variables jaw of treatment and smoking had a significant influence on peri-implant bone level change on the FPD level, but not on the implant or surface levels. The model explained only 10% of the observed variance in the bone level change. The study failed to demonstrate that the presence of cantilever extensions in an FPD had an effect on peri-implant bone loss.

  5. Work function increase of Al-doped ZnO thin films by B+ ion implantation.

    Science.gov (United States)

    Hong, Sang-Jin; Heo, Gi-Seok; Park, Jong-Woon; Lee, In-Hwan; Choi, Bum-Ho; Lee, Jong-Ho; Park, Se-Yeon; Shin, Dong-Chan

    2007-11-01

    The work function of an Al-doped ZnO (AZO) thin film can be increased via B+ ion implantation from 3.92 eV up to 4.22 eV. The ion implantation has been carried out with the ion dose of 1 x 10(16) cm(-2) and ion energy of 5 keV. The resistance of the B+ implanted AZO films has been a bit raised, while their transmittance is slightly lowered, compared to those of un-implanted AZO films. These behaviors can be explained by the doping profile and the resultant band diagram. It is concluded that the coupling between the B+ ions and oxygen vacancies would be the main reason for an increase in the work function and a change in the other properties. We also address that the work function is more effectively alterable if the defect density of the top transparent conducting oxide layer can be controlled.

  6. Nanotubes Functionalized with BMP2 Knuckle Peptide Improve the Osseointegration of Titanium Implants in Rabbits.

    Science.gov (United States)

    Ma, Yuanping; Zhang, Zhenting; Liu, Yiran; Li, Hongyi; Wang, Na; Liu, Wenwen; Li, Wenjun; Jin, Lingling; Wang, Jinshu; Chen, Su

    2015-02-01

    To determine the effects of surface modification on implant osseointegration in vivo, we first immobilized polydopamine onto 70-nm diameter TiO2 nanotubes as an intermediate layer, and then conjugated a 21 amino acid peptide sequence (the so-called "knuckle peptide") of bone morphogenetic protein-2 (BMP-2) onto the nanotubes created by electrochemical anodization. We inserted these implants into the tibiae of rabbits and measured the gene expression and bone formation around them. The successful fabrication of BMP-2 knuckle peptide was confirmed by contact angle measurement, X-ray photoelectron spectroscopy, and Fourier transform infrared spectroscopy. The histological features and the amount of bone fluorescence around the implants on non-decalcified sections were investigated at 3, 5, 8, and 12 weeks after implantation using traditional light and fluorescence microscopy, and the gene expression of alkaline phosphatase, osterix, collagen-I, and tartrate-resistant acid phosphatase was examined by real-time PCR at 1, 2, 3, 4, and 5 weeks after implantation. The results demonstrated a significant increase in bone-implant contact, quantity of fluorescence, and gene expression levels of the bone attached to implants with immobilized BMP-2 knuckle peptide compared with the other two control groups. In conclusion, the surface functionalization of TiO2 nanotubes with BMP-2 knuckle peptide was beneficial for osseointegration and this approach could be further developed to improve Ti-based implants for various applications.

  7. Functional biocompatibility testing of silicone breast implants and a novel classification system based on surface roughness.

    Science.gov (United States)

    Barr, S; Hill, E W; Bayat, A

    2017-06-27

    Increasing numbers of women undergo breast implantation for cosmetic and reconstructive purposes. Contracture of the fibrous capsule, which encases the implant leads to significant pain and reoperation. Texture, wettability and the cellular reaction to implant surfaces are poorly understood determinants of implant biocompatibility. The aim of this study was to evaluate the in-vitro characteristics of a range of commercial available implants using a macrophage based assay of implant biocompatibility and a quantitative assessment of wettability and texture. Thirteen commercially available surfaces were subjected to wettability and texture characterisation using scanning and laser confocal microscopy. THP-1 macrophages were cultured on their surfaces and assessed using Integrin αV immunocytochemistry, SEM and RT-PCR for the expression of TNF-Alpha, IL-6, IL-10 and a cytokine array for the production of TNF-alpha, IL-10, IL-1RA and IL1β; important indicators of inflammation and macrophage polarization. Textured surfaces can be accurately sub-categorized dependent upon roughness and re-entrant features into four main types (macro, micro, meso and nano-textured surfaces). Significant (P based on roughness and present a macrophage based assay of breast implant biocompatibility with a quantitative assessment of implant wettability and texture. The breast implant surface-cell interaction is variable and sufficient to alter healing response and capsular contracture fate in-vivo. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Microscopic Study of Surface Microtopographic Characteristics of Dental Implants.

    Science.gov (United States)

    Sezin, M; Croharé, L; Ibañez, J C

    2016-01-01

    To determine and compare the micro topographic characteristics of dental implants submitted to different surface treatments, using scanning electron microscopy (SEM). Implants were divided into 7 groups of 3 specimens each, according to the surface treatment used: group 1: Osseotite, BIOMET 3i; group 2: SLA surface, Institut Straumann AG; group 3: Oxalife surface, Tree-Oss implant; group 4: B&W implant surface; group 5: Q-implant surface; group 6: ML implant surface; group 7: RBM surface, Rosterdent implant. The surfaces were examined under SEM (Carl Zeiss FE-SEM-SIGMA). Image Proplus software was used to determine the number and mean diameter of pores per area unit (mm). The data obtained were analyzed with the Mann-Whitney test. A confocal laser microscope (LEXT-OLS4100 Olympus) was used to conduct the comparative study of surface roughness (Ra). Data were analyzed using Tukey's HSD test. The largest average pore diameter calculated in microns was found in group 5 (3.45 µm+/-1.91) while the smallest in group 7 (1.47µm+/-1.29). Significant differences were observed among each one of the groups studied (p<0.05). The largest number of pores/mm(2) was found in group 2 (229343) and the smallest number in group 4 (10937). Group 2 showed significant differences regarding the other groups (p<0.05). The greatest roughness (Ra) was observed in group 2 (0.975µm+/-0.115) and the smallest in group 4 (0.304µm+/-0.063). Group 2 was significantly different from the other groups (p<0.05). The micro topography observed in the different groups presented dissimilar and specific features, depending on the chemical treatment used for the surfaces..

  9. Microscopic Study of Surface Microtopographic Characteristics of Dental Implants

    Science.gov (United States)

    Sezin, M.; Croharé, L.; Ibañez, J.C.

    2016-01-01

    Objective: To determine and compare the micro topographic characteristics of dental implants submitted to different surface treatments, using scanning electron microscopy (SEM). Materials and Methods: Implants were divided into 7 groups of 3 specimens each, according to the surface treatment used: group 1: Osseotite, BIOMET 3i; group 2: SLA surface, Institut Straumann AG; group 3: Oxalife surface, Tree-Oss implant; group 4: B&W implant surface; group 5: Q-implant surface; group 6: ML implant surface; group 7: RBM surface, Rosterdent implant. The surfaces were examined under SEM (Carl Zeiss FE-SEM-SIGMA). Image Proplus software was used to determine the number and mean diameter of pores per area unit (mm). The data obtained were analyzed with the Mann-Whitney test. A confocal laser microscope (LEXT-OLS4100 Olympus) was used to conduct the comparative study of surface roughness (Ra). Data were analyzed using Tukey's HSD test. Results: The largest average pore diameter calculated in microns was found in group 5 (3.45 µm+/-1.91) while the smallest in group 7 (1.47µm+/-1.29). Significant differences were observed among each one of the groups studied (p<0.05). The largest number of pores/mm2 was found in group 2 (229343) and the smallest number in group 4 (10937). Group 2 showed significant differences regarding the other groups (p<0.05). The greatest roughness (Ra) was observed in group 2 (0.975µm+/-0.115) and the smallest in group 4 (0.304µm+/-0.063). Group 2 was significantly different from the other groups (p<0.05). Conclusion: The micro topography observed in the different groups presented dissimilar and specific features, depending on the chemical treatment used for the surfaces.. PMID:27335615

  10. A Multicentre Study of CLa Implant and Sino-implant Expanded Application (two-year follow-up)

    Institute of Scientific and Technical Information of China (English)

    方可娟; 关艳敏; 范慧民; 高尔生; 杨丹; 薜丽; 韩耀玲; 刘宝

    1997-01-01

    A multicentre comparative clinical study of CLa implant and Sino-implant was carried out at 100 subcentres in 11 provinces, and a total of 19673 subjects were recruited. Two year follow up has been finished. The follow-up rate at the end of two years was 94,29%. Two-year cumulative continuation rate per 100 women for Sino-implant(89.93) was significantly higher than that for CLa implant (88.89). Two-year cumulative pregnancy rates per 100 women were 0.0462(CLa implant) and 0.281(Sino-implant) respectively; there was statistically significant difference between them. No ectopic pregnancy was recorded among CLa implant users and three ectopic pregnancies were reported among Sino implant users,resulting in an ectopic pregnancy rate of 0.163 per 1000 women years. The incidence of side-effects appeared to diminish with time. The major side effects were the menstrual disturbances, which accounted for more than 90% of the total sideeffects, and the incidence of frequent menstruation, irregular bleeding and spotring was higher than that of infrequentjscanty menstruation and amenorrhea. Use of CLa implant had higher incidence of amenorrhea and infrequentjscanty menstruation than that of Sin-imptant. During two-year follow-up, the number of discontinuation due to menstrual problems contributed 78% of the total number of discontinuation; two year menstrual-related cumulative discontinuation rates were 8.96 per 100 women for CLa implant and 7.84 for Sino-implant; there was statistically significant difference(P< 0.01). Two-year study shows that the two types of implant are similar to Norplant in the incidence of side-effects and contraceptive efficacy as well as two year continuation rates.

  11. Comparative Study of Bio-implantable Acoustic Generator Architectures

    Science.gov (United States)

    Christensen, D.; Roundy, S.

    2013-12-01

    This paper is a comparative study of the design spaces of two bio-implantable acoustically excited generator architectures: the thickness-stretch-mode circular piezoelectric plate and the bending-mode unimorph piezoelectric diaphragm. The generators are part of an acoustic power transfer system for implanted sensors and medical devices such as glucose monitors, metabolic monitors, drug delivery systems, etc. Our studies indicate that at small sizes the diaphragm architecture outperforms the plate architecture. This paper will present the results of simulation studies and initial experiments that explore the characteristics of the two architectures and compare their performance.

  12. Functional tooth restoration by next-generation bio-hybrid implant as a bio-hybrid artificial organ replacement therapy.

    Science.gov (United States)

    Oshima, Masamitsu; Inoue, Kaoru; Nakajima, Kei; Tachikawa, Tetsuhiko; Yamazaki, Hiromichi; Isobe, Tomohide; Sugawara, Ayaka; Ogawa, Miho; Tanaka, Chie; Saito, Masahiro; Kasugai, Shohei; Takano-Yamamoto, Teruko; Inoue, Takashi; Tezuka, Katsunari; Kuboki, Takuo; Yamaguchi, Akira; Tsuji, Takashi

    2014-01-01

    Bio-hybrid artificial organs are an attractive concept to restore organ function through precise biological cooperation with surrounding tissues in vivo. However, in bio-hybrid artificial organs, an artificial organ with fibrous connective tissues, including muscles, tendons and ligaments, has not been developed. Here, we have enveloped with embryonic dental follicle tissue around a HA-coated dental implant, and transplanted into the lower first molar region of a murine tooth-loss model. We successfully developed a novel fibrous connected tooth implant using a HA-coated dental implant and dental follicle stem cells as a bio-hybrid organ. This bio-hybrid implant restored physiological functions, including bone remodelling, regeneration of severe bone-defect and responsiveness to noxious stimuli, through regeneration with periodontal tissues, such as periodontal ligament and cementum. Thus, this study represents the potential for a next-generation bio-hybrid implant for tooth loss as a future bio-hybrid artificial organ replacement therapy.

  13. Multicenter study with a direct acoustic cochlear implant

    NARCIS (Netherlands)

    Lenarz, T.; Zwartenkot, J.W.; Stieger, C.; Schwab, B.; Mylanus, E.A.M.; Caversaccio, M.; Kompis, M.; Snik, A.F.M.; D'Hondt, C.; Mojallal, H.

    2013-01-01

    OBJECTIVE: To confirm the clinical efficacy and safety of a direct acoustic cochlear implant. STUDY DESIGN: Prospective multicenter study. SETTING: The study was performed at 3 university hospitals in Europe (Germany, The Netherlands, and Switzerland). PATIENTS: Fifteen patients with severe-to-profo

  14. Mandibular overdentures supported by two Branemark, IMZ or ITI implants : a 5-year prospective study

    NARCIS (Netherlands)

    Meijer, HJA; Batenburg, RHK; Raghoebar, GM; Vissink, A

    2004-01-01

    Objectives: The aim of this prospective comparative study was to evaluate the survival rate and the condition of the peri-implant tissues of the IMZ implant system (two-stage cylindertype), the Branemark implant system (two-stage screwtype) and the ITI implant system (one-stage screwtype) supporting

  15. Functional Chest Wall Reconstruction With a Biomechanical Three-Dimensionally Printed Implant.

    Science.gov (United States)

    Moradiellos, Javier; Amor, Sergio; Córdoba, Mar; Rocco, Gaetano; Vidal, Mercedes; Varela, Andrés

    2017-04-01

    Chest wall resection and reconstruction for neoplastic diseases has unique oncologic, structural, and functional challenges. In a young and fit patient with a mediastinal mass and extensive anterior chest wall invasion, purely structural solutions were deemed insufficient. We hereby present a novel three-dimensionally printed patient-specific titanium implant of sternum and ribs. This osteointegrable implant was designed with biomechanical capabilities using a unique "Greek wave" folding pattern. Postoperative dynamic computed tomography showed that the implant allowed for controlled flexing during the respiratory cycle. Three-dimensional printing with biocompatible materials could enable a new generation of chest wall implants strongly focused on functional reconstruction. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  16. Cochlear Implants in the Inclusive Classroom: A Case Study

    Science.gov (United States)

    Jachova, Zora; Kovacevic, Jasmina

    2010-01-01

    This article presents a case study of a child aged 12 years with a cochlear implant who is attending a mainstream educational setting in Skopje, FYR Macedonia. The study, which uses both qualitative and quantitative data, took place over a period of 12 months. It illustrates the importance of professional development and training of teachers and a…

  17. Oral rehabilitation with implant-supported fixed partial dentures in periodontitis-susceptible subjects. A 5-year prospective study.

    Science.gov (United States)

    Wennström, Jan L; Ekestubbe, Annika; Gröndahl, Kerstin; Karlsson, Stig; Lindhe, Jan

    2004-09-01

    Comparatively few studies with at least 5 years of follow-up are available that describe the use of implants in prosthetic rehabilitation of partially edentulous patients. Randomized, controlled clinical studies that evaluated the effect of different surface designs of screw-shaped implants on the outcome of treatment are also sparse. To determine, in a prospective randomized, controlled clinical trial, the outcome of restorative therapy in periodontitis-susceptible patients who, following basic periodontal therapy, had been restored with implants with either a machined- or a rough-surface topography. Fifty-one subjects (mean age, 59.5 years), 20 males and 31 females who, following treatment of moderate-to-advanced chronic periodontitis, required implant therapy for prosthetic rehabilitation were recruited. Seventeen of the patients were current smokers. Following the active treatment, all subjects were included in an individually designed maintenance program. A total of 56 fixed partial dentures (FPDs) and a total of 149 screw-shaped, and self-tapping implants (Astra Tech implants) -- 83 in the maxilla and 66 in the mandible -- were installed in a two-stage procedure. Each patient received a minimum of two implants and by randomization every second implant that was installed had been designed with a machined surface and the remaining with a roughened Tioblast surface. Abutment connection was performed 3-6 months after implant installation. Clinical and radiographical examinations were performed following FPD connection and once a year during a 5-year follow-up period. The analysis of peri-implant bone-level alterations was performed on subject, FPD and implant levels. Four patients and four FPDs were lost to the 5 years of monitoring. One implant (machined surface) did not properly integrate (early failure), and was removed at the time of abutment connection. Three implants were lost during function and a further eight implants could not be accounted for at the 5

  18. On-Site Surface Functionalization for Titanium Dental Implant with Nanotopography: Review and Outlook

    OpenAIRE

    Byung Gyu Kim; Seog-Jin Seo; Jung-Hwan Lee; Hae-Won Kim

    2016-01-01

    Titanium (Ti) has been the first choice of material for dental implant due to bonding ability to natural bone and great biocompatibility. Various types of surface roughness modification in nanoscale have been made as promising strategy for accelerating osseointegration of Ti dental implant. To have synergetic effect with nanotopography oriented favors in cell attachment, on-site surface functionalization with reproducibility of nanotopography is introduced as next strategy to further enhance ...

  19. Lattice location study of implanted In in Ge

    CERN Document Server

    Decoster, S; Wahl, U; Correia, J G; Vantomme, A

    2009-01-01

    We report on emission channeling experiments to determine the lattice location and the thermal stability of implanted $^{111}$In atoms in Ge. The majority of the In atoms was found on the substitutional site, which is a thermally stable site at least up to 500 °C. We also found strong indication that directly after implantation, a fraction of the implanted $^{111}$In atoms occupies the bond-centered BC site. This fraction disappears after annealing at 300 °C. From comparison with ab initio calculations, electrical studies, and perturbed angular correlation experiments, the In atoms on the BC site can be related to In-vacancy and In-self-interstitial defect complexes. The activation energy for dissociation of this BC related defect was found to be below 1.6 eV.

  20. Overview of Implant Infections in Orthopaedics Department: Retrospective Study

    Directory of Open Access Journals (Sweden)

    Tugrul Bulut

    2014-12-01

    Full Text Available In this study, our aim was to evaluate the antibiotic susceptibility of bacteria isolated from orthopedic implant infections. Within two years operated 1996 patients in an orthopedics and traumatology clinic were retrospectively investigated. Seventy-six (76/1996, 3.8% orthopedic implant infections were detected. Isolated bacteria and their antibiotic susceptibility patterns were analyzed. The bacteries isolated from implant related infections and antibiotic sensitivity patterns were evaluated retrospectively in our orthopaedics and traumatology clinic. Staphylococcus aureus was the predominant organism (30.3%. Gram negative bacterias were isolated in 65.8% of our patients. No resistance was determined against vancomycin and linezolid in gram positive bacterias. Imipenem, amicasin and cefepim was seen as the most effective antibiotics for gram negative bacterias.

  1. Study of ion implantation profiles by the PIXE technique

    Science.gov (United States)

    Midy, P.; Lagarde, G.; Brissaud, I.; Frontier, J. P.; Chaumont, J.

    1998-03-01

    The RBS technique is currently used with alpha particles as a non-destructive way of studying concentration depth profiles. This technique is especially convenient in characterizing heavy atom distributions inside a matrix of lighter elements, and its use is less convenient in the case of light elements in a matrix of heavier ones. On the other hand the probing depth is limited by the small range of alpha particles in the matrix. We present here a new procedure for determining ion implantation profiles by means of the PIXE technique and by varying the impinging proton energy. As an example, silicon ions of two energies have been implanted into pure titanium samples in order to obtain implantation profiles with a double peak. The results presented here are in good agreement with the calculations using the TRIM code.

  2. Implant Optimisation for Primary Hip Replacement in Patients over 60 Years with Osteoarthritis: A Cohort Study of Clinical Outcomes and Implant Costs Using Data from England and Wales.

    Directory of Open Access Journals (Sweden)

    Simon S Jameson

    Full Text Available Hip replacement is one of the most commonly performed surgical procedures worldwide; hundreds of implant configurations provide options for femoral head size, joint surface material and fixation method with dramatically varying costs. Robust comparative evidence to inform the choice of implant is needed. This retrospective cohort study uses linked national databases from England and Wales to determine the optimal type of replacement for patients over 60 years undergoing hip replacement for osteoarthritis.Implants included were the commonest brand from each of the four types of replacement (cemented, cementless, hybrid and resurfacing; the reference prosthesis was the cemented hip procedure. Patient reported outcome scores (PROMs, costs and risk of repeat (revision surgery were examined. Multivariable analyses included analysis of covariance to assess improvement in PROMs (Oxford hip score, OHS, and EQ5D index (9159 linked episodes and competing risks modelling of implant survival (79,775 procedures. Cost of implants and ancillary equipment were obtained from National Health Service procurement data.EQ5D score improvements (at 6 months were similar for all hip replacement types. In females, revision risk was significantly higher in cementless hip prostheses (hazard ratio, HR = 2.22, p<0.001, when compared to the reference hip. Although improvement in OHS was statistically higher (22.1 versus 20.5, p<0.001 for cementless implants, this small difference is unlikely to be clinically important. In males, revision risk was significantly higher in cementless (HR = 1.95, p = 0.003 and resurfacing implants, HR = 3.46, p<0.001, with no differences in OHS. Material costs were lowest with the reference implant (cemented, range £1103 to £1524 and highest with cementless implants (£1928 to £4285. Limitations include the design of the study, which is intrinsically vulnerable to omitted variables, a paucity of long-term implant survival data (reflecting the

  3. Impact of Crown-Implant Ratio of Single Restorations Supported by 6-mm Implants : A Short-Term Case Series Study

    NARCIS (Netherlands)

    Guljé, Felix L; Raghoebar, Gerry M; Erkens, Ward Al; Meijer, Henny Ja

    2016-01-01

    PURPOSE: High crown-implant ratios might affect the biologic and technical performance of a reconstruction. The aim of this study was to assess whether a higher crown-implant ratio of single restorations on 6-mm implants resulted in more peri-implant bone loss and more prosthetic complications durin

  4. Early radiographic diagnosis of peri-implantitis enhances the outcome of peri-implantitis treatment: a 5-year retrospective study after non-surgical treatment

    OpenAIRE

    Chang, Hee-Yung; Park, Shin-Young; Kim, Jin-Ah; Kim, Young-Kyun; Lee, Hyo-Jung

    2015-01-01

    Purpose This retrospective study evaluated the relationship between the timing of peri-implantitis diagnosis and marginal bone level after a 5-year follow-up of non-surgical peri-implantitis treatment. Methods Thirty-three patients (69 implants) were given peri-implantitis diagnosis in 2008-2009 in Seoul National University Bundang Hospital. Among them, 31 implants from 16 patients were included in this study. They were treated non-surgically in this hospital, and came for regular maintenance...

  5. GnRH-agonist implants suppress reproductive function and affects ovarian LHR and FSHR expression in prepubertal female cats.

    Science.gov (United States)

    Mehl, N S; Srisuwatanasagul, S; Swangchan-Uthai, T; Sirivaidyapong, S; Khalid, M

    2017-01-01

    Effect of a GnRH-agonist (deslorelin) was studied on reproductive function and ovarian luteinizing hormone receptor (LHR) and follicle stimulating hormone receptor (FSHR) expression in prepubertal female cats that were either implanted with 4.7-mg deslorelin (implanted: n = 6) or not (controls: n = 18) or ovariohysterectomized at prepubertal age (prepubertal OVH: n = 6). Body weights, fecal estradiol, and sexual behavior of implanted and control cats were monitored for 48 weeks followed by collection of ovaries and uteri. Ovaries and uteri were collected from control cats at follicular, luteal, and inactive stage (n = 6/group) and from prepubertal OVH cats at prepubertal age. Ovaries and uteri were analyzed for anatomical/histological characteristics. Ovaries were also analyzed for LHR and FSHR expression. Statistical analysis showed higher (P ≤ 0.05) body weight in control than implanted cats only during 22nd to 26th weeks of the study. Estrus was observed in control cats only. Deslorelin reduced (P ≤ 0.05) ovarian weight and number of antral follicles but did not affect endometrial thickness and gland diameter. However, myometrial thickness of implanted cats was significantly lower than control cats at follicular and luteal stage. Ovarian LHR mRNA expression was lower (P ≤ 0.05) in implanted cats than control cats at follicular stage. FSHR mRNA and LHR protein expression did not differ among the three groups. FSHR protein expression was lower (P ≤ 0.05) in prepubertal OVH cats and was not affected by deslorelin. In conclusion, deslorelin suppresses reproductive function in prepubertal female cats for at least 48 weeks possibly through a change in the ovarian mRNA expression of LHR. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. 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...

  7. An Implantable Neuroprosthetic Device to Normalize Bladder Function after SCI

    Science.gov (United States)

    2014-12-01

    However, before these applications become possible, the responses from these visceral organs to PNS will have to be determined. This study only tested...et al. 2011), block chronic pain of peripheral origin (Cuellar et al. 2013; van Buyten et al. 2013), or restore urinary function after spinal cord...applications to block chronic pain (Cuellar et al. 2013; van Buyten et al. 2013). Understanding the mechanisms underlying this type of nerve block could

  8. Functional results of dental restoration with osseointegrated implants after mandible reconstruction.

    Science.gov (United States)

    Gürlek, A; Miller, M J; Jacob, R F; Lively, J A; Schusterman, M A

    1998-03-01

    We reviewed the cases of 20 cancer patients (mean age 47.4 years) in whom osseointegrated implants were used for dental restoration after mandibular reconstruction between January of 1988 and December of 1994. Seventy-one implants were placed into bone flaps (n = 60) or native mandible (n = 11), an average of 3.55 per patient (range, 2 to 5). Successful integration occurred in 91.5 percent (65 of 71); there were five early failures and one late failure, with no significant difference between the number lost in microvascular flaps (5 of 60) and native mandible (1 of 11) (as determined by Fisher's exact test). Functional evaluation included assessments of diet, speech, and cosmesis. Based on our review, we concluded that (1) implants enhance dental restoration in selected patients, and (2) microvascular bone flaps, including the fibula and iliac crest, are well suited for dental implant restoration.

  9. Radiobiology for eye plaque brachytherapy and evaluation of implant duration and radionuclide choice using an objective function

    Energy Technology Data Exchange (ETDEWEB)

    Gagne, Nolan L.; Leonard, Kara L.; Rivard, Mark J. [Department of Radiation Oncology, Tufts University School of Medicine, Boston, Massachusetts 02111 (United States)

    2012-06-15

    Purpose: Clinical optimization of Collaborative Ocular Melanoma Study (COMS) eye plaque brachytherapy is currently limited to tumor coverage, consensus prescription dosage, and dose calculations to ocular structures. The biologically effective dose (BED) of temporary brachytherapy treatments is a function of both chosen radionuclide R and implant duration T. This study endeavored to evaluate BED delivered to the tumor volume and surrounding ocular structures as a function of plaque position P, prescription dose, R, and T. Methods: Plaque-heterogeneity-corrected dose distributions were generated with MCNP5 for the range of currently available COMS plaques loaded with sources using three available low-energy radionuclides. These physical dose distributions were imported into the PINNACLE{sup 3} treatment planning system using the TG-43 hybrid technique and used to generate dose volume histograms for a T = 7 day implant within a reference eye geometry including the ciliary body, cornea, eyelid, foveola, lacrimal gland, lens, optic disc, optic nerve, retina, and tumor at eight standard treatment positions. The equation of Dale and Jones was employed to create biologically effective dose volume histograms (BEDVHs), allowing for BED volumetric analysis of all ROIs. Isobiologically effective prescription doses were calculated for T = 5 days down to 0.01 days, with BEDVHs subsequently generated for all ROIs using correspondingly reduced prescription doses. Objective functions were created to evaluate the BEDVHs as a function of R and T. These objective functions are mathematically accessible and sufficiently general to be applied to temporary or permanent brachytherapy implants for a variety of disease sites. Results: Reducing T from 7 to 0.01 days for a 10 mm plaque produced an average BED benefit of 26%, 20%, and 17% for {sup 103}Pd, {sup 125}I, and {sup 131}Cs, respectively, for all P; 16 and 22 mm plaque results were more position-dependent. {sup 103}Pd produced a 16

  10. Comparison of Functional Outcomes of Total Knee Arthroplasty Using Two Different Single Radius Implants

    Directory of Open Access Journals (Sweden)

    Amir Pourmoghaddam

    2016-04-01

    Full Text Available Total knee arthroplasty is used as the treatment plan for patients with end-stage osteoarthrosis associated with severely affected function. Although TKA has been used for many years, some patients have reported overall dissatisfaction regarding the outcome. This may be due to the complexity of the joint design. In recent years, the concept of single-radius knee prosthetics is gaining more popularity as many studies have discussed biomechanical and clinical benefits of such design compared to traditionally used multi-radius implants. In this study, we report the outcome of 78 patients who were treated by TKA utilizing a relatively new single-radius implant, Unity. Results showed that all subjects reported good outcomes as expressed by significant improvement in their Knee Injury and Osteoarthritis Outcome Scores at 1-year post-operative. The symptom, pain, and ADL subscores demonstrated significant improvement in patients with scores twice the pre-operative value, while the average improvement in sport and quality of life subscores showed even greater improvement with scores three times the pre-operative value.

  11. Randomised controlled trial of extraarticular gold bead implantation for treatment of knee osteoarthritis: a pilot study

    DEFF Research Database (Denmark)

    Nejrup, Kirsten; Olivarius, Niels de Fine; Jacobsen, Judith L.

    2008-01-01

    The primary objective of this double-blind, randomised, controlled trial was to determine if implanting gold beads at five acupuncture points around the knee joint improves 1-year outcomes for patients with osteoarthritis (OA) of the knee. Participants were 43 adults aged 18-80 years with pain...... and stiffness from non-specific OA of the knee for over a year. The intervention was blinded implantation of gold beads at five acupuncture points around the affected knee through a hypodermic needle, or needle insertion alone. Primary outcome measures were knee pain, stiffness and function assessed...... acupuncture had greater relative improvements in self-assessed outcomes. The treatment was well tolerated. This 1-year pilot study indicates that extraarticular gold bead implantation is a promising treatment modality for patients with OA of the knee. The new treatment should be tested in a larger trial...

  12. Functional investigation of bone implant viability using radiotracers in a new model of osteonecrosis

    Directory of Open Access Journals (Sweden)

    Luis Schiper

    Full Text Available OBJECTIVES: Conventional imaging methods are excellent for the morphological characterization of the consequences of osteonecrosis; however, only specialized techniques have been considered useful for obtaining functional information. To explore the affinity of radiotracers for severely devascularized bone, a new mouse model of isolated femur implanted in a subcutaneous abdominal pocket was devised. To maintain animal mobility and longevity, the femur was harvested from syngeneic donors. Two technetium-99m-labeled tracers targeting angiogenesis and bone matrix were selected. METHODS: Medronic acid and a homodimer peptide conjugated with RGDfK were radiolabeled with technetium-99m, and biodistribution was evaluated in Swiss mice. The grafted and control femurs were evaluated after 15, 30 and 60 days, including computed tomography (CT and histological analysis. RESULTS: Radiolabeling achieved high (>95% radiochemical purity. The biodistribution confirmed good blood clearance 1 hour after administration. For 99mTc-hydrazinonicotinic acid (HYNIC-E-[c(RGDfK2, remarkable renal excretion was observed compared to 99mTc-methylene diphosphonate (MDP, but the latter, as expected, revealed higher bone uptake. The results obtained in the control femur were equal at all time points. In the implanted femur, 99mTc-HYNIC-E-[c(RGDfK2 uptake was highest after 15 days, consistent with early angiogenesis. Regarding 99mTc-MDP in the implant, similar uptake was documented at all time points, consistent with sustained bone viability; however, the uptake was lower than that detected in the control femur, as confirmed by histology. CONCLUSIONS: 1 Graft viability was successfully diagnosed using radiotracers in severely ischemic bone at all time points. 2 Analogously, indirect information about angiogenesis could be gathered using 999mTc-HYNIC-E-[c(RGDfK2. 3 These techniques appear promising and warrant further studies to determine their potential clinical applications.

  13. Functional investigation of bone implant viability using radiotracers in a new model of osteonecrosis

    Science.gov (United States)

    Schiper, Luis; Faintuch, Bluma Linkowski; da Silva Badaró, Roberto José; de Oliveira, Erica Aparecida; Chavez, Victor E. Arana; Chinen, Elisangela; Faintuch, Joel

    2016-01-01

    OBJECTIVES: Conventional imaging methods are excellent for the morphological characterization of the consequences of osteonecrosis; however, only specialized techniques have been considered useful for obtaining functional information. To explore the affinity of radiotracers for severely devascularized bone, a new mouse model of isolated femur implanted in a subcutaneous abdominal pocket was devised. To maintain animal mobility and longevity, the femur was harvested from syngeneic donors. Two technetium-99m-labeled tracers targeting angiogenesis and bone matrix were selected. METHODS: Medronic acid and a homodimer peptide conjugated with RGDfK were radiolabeled with technetium-99m, and biodistribution was evaluated in Swiss mice. The grafted and control femurs were evaluated after 15, 30 and 60 days, including computed tomography (CT) and histological analysis. RESULTS: Radiolabeling achieved high (>95%) radiochemical purity. The biodistribution confirmed good blood clearance 1 hour after administration. For 99mTc-hydrazinonicotinic acid (HYNIC)-E-[c(RGDfK)2, remarkable renal excretion was observed compared to 99mTc-methylene diphosphonate (MDP), but the latter, as expected, revealed higher bone uptake. The results obtained in the control femur were equal at all time points. In the implanted femur, 99mTc-HYNIC-E-[c(RGDfK)2 uptake was highest after 15 days, consistent with early angiogenesis. Regarding 99mTc-MDP in the implant, similar uptake was documented at all time points, consistent with sustained bone viability; however, the uptake was lower than that detected in the control femur, as confirmed by histology. CONCLUSIONS: 1) Graft viability was successfully diagnosed using radiotracers in severely ischemic bone at all time points. 2) Analogously, indirect information about angiogenesis could be gathered using 999mTc-HYNIC-E-[c(RGDfK)2. 3) These techniques appear promising and warrant further studies to determine their potential clinical applications.

  14. A Prospective, Longitudinal Study of US Children Unable to Achieve Open-Set Speech Recognition Five Years after Cochlear Implantation

    Science.gov (United States)

    Barnard, JM; Fisher, LM; Johnson, KC; Eisenberg, LS; Wang, NY; Quittner, AL; Carson, CM; Niparko, JK

    2015-01-01

    Objective To identify characteristics associated with inability to progress to open-set speech recognition in children who are 5 years post cochlear implantation. Study Design Prospective, longitudinal and multidimensional assessment of auditory development over 5 years. Setting Six tertiary cochlear implant (CI) referral centers in the US. Patients Children with severe-to-profound hearing loss who underwent implantation before age 5 years enrolled in the Childhood Development after Cochlear Implant (CDaCI) study, categorized by level of speech recognition ability. Intervention(s) Cochlear implantation prior to 5 years of age and annual assessment of emergent speech recognition skills. Main outcome measure(s) Progression to open-set speech recognition by 5 years after implantation. Results Less functional hearing prior to implantation, older age at onset of amplification, lower maternal sensitivity to communication needs, minority status, and complicated perinatal history were associated with inability to obtain open set speech recognition by 5 years. Conclusions Characteristics of a subpopulation of children with CIs that were associated with an inability to achieve open-set speech recognition after 5 years of CI experience were investigated. These data distinguish pediatric CI recipients at risk for poor auditory development and highlight areas for future interventions to enhance support of early implantation. PMID:25700015

  15. Bone Response to Surface-Modified Titanium Implants: Studies on the Early Tissue Response to Implants with Different Surface Characteristics

    Directory of Open Access Journals (Sweden)

    C. Larsson Wexell

    2013-01-01

    Full Text Available In a series of experimental studies, the bone formation around systematically modified titanium implants is analyzed. In the present study, three different surface modifications were prepared and evaluated. Glow-discharge cleaning and oxidizing resulted in a highly stoichiometric TiO2 surface, while a glow-discharge treatment in nitrogen gas resulted in implants with essentially a surface of titanium nitride, covered with a very thin titanium oxide. Finally, hydrogen peroxide treatment of implants resulted in an almost stoichiometric TiO2, rich in hydroxyl groups on the surface. Machined commercially pure titanium implants served as controls. Scanning Auger Electron Spectroscopy, Scanning Electron Microscopy, and Atomic Force Microscopy revealed no significant differences in oxide thickness or surface roughness parameters, but differences in the surface chemical composition and apparent topography were observed. After surface preparation, the implants were inserted in cortical bone of rabbits and evaluated after 1, 3, and 6 weeks. Light microscopic evaluation of the tissue response showed that all implants were in contact with bone and had a large proportion of newly formed bone within the threads after 6 weeks. There were no morphological differences between the four groups. Our study shows that a high degree of bone contact and bone formation can be achieved with titanium implants of different surface composition and topography.

  16. PET studies of parkinsonian patients treated with autologous adrenal implants.

    Science.gov (United States)

    Guttman, M; Burns, R S; Martin, W R; Peppard, R F; Adam, M J; Ruth, T J; Allen, G; Parker, R A; Tulipan, N B; Calne, D B

    1989-08-01

    Transplantation of autologous adrenal medulla tissue into the striatum has recently been proposed as a treatment for Parkinson's disease. We report the use of positron emission tomography (PET) to evaluate patients who had adrenal implants placed into the right caudate. 6-[18F] fluoro-L-dopa (6-FD) scans were performed to study the integrity and activity of the implant, and the nigrostriatal dopamine system before and six weeks after transplantation surgery. [68Ga] Gallium-ethylenediaminetetraacetate (Ga) scans were also performed to assess the blood brain barrier. The Ga scans performed on two patients showed increased permeability of the blood brain barrier at the surgical site. 6-FD PET scans in five patients did not show a consistent change in striatal uptake following adrenal medullary implantation after six weeks. Further assessment of implant viability with 6-FD PET scans after longer follow up may provide useful information if the blood-brain barrier becomes re-established with the passage of time.

  17. Effect of unilateral and simultaneous bilateral cochlear implantation on tinnitus: A Prospective Study

    NARCIS (Netherlands)

    Zon, A. van; Smulders, Y.E.; Ramakers, G.G.; Stegeman, I.; Smit, A.L.; Zanten, G.A.; Stokroos, R.J.; Hendrice, N.; Free, R.H.; Maat, B.; Frijns, J.H.; Mylanus, E.A.M.; Huinck, W.J.; Topsakal, V.; Tange, R.A.; Grolman, W.

    2016-01-01

    OBJECTIVES/HYPOTHESIS: To determine the effect of cochlear implantation on tinnitus perception in patients with severe bilateral postlingual sensorineural hearing loss and to demonstrate possible differences between unilateral and bilateral cochlear implantation. STUDY DESIGN: Prospective study. MET

  18. Neurotherapeutic and neuroprosthetic effects of implanted functional electrical stimulation for ambulation after incomplete spinal cord injury

    Directory of Open Access Journals (Sweden)

    Ronald J. Triolo, PhD

    2010-03-01

    Full Text Available The purpose of this single-subject study was to determine the neurotherapeutic and neuroprosthetic effects of an implanted functional electrical stimulation (FES system designed to facilitate walking in an individual with a long-standing motor and sensory incomplete spinal cord injury. An implanted pulse generator and eight intramuscular stimulating electrodes were installed unilaterally, activating weak or paralyzed hip flexors, hip and knee extensors, and ankle dorsiflexors during 36 sessions of gait training with FES. The neurotherapeutic effects were assessed by a comparison of pre- and posttraining volitional walking. The neuroprosthetic effects were assessed by a comparison of posttraining volitional and FES-assisted walking. Treatment resulted in significant (p < 0.005 volitional improvements in 6-minute walking distance and speed, speed during maximum walk, double support time, and 10 m walking speed. Posttraining FES-assisted walking resulted in significant additional improvements in all these measures, except 10 m walking speed. When the subject was using FES-assisted gait, maximum walking distance, peak knee flexion in swing, peak ankle dorsiflexion in swing, and knee extension moment also significantly increased. Neuroprosthetic gains were sufficient to enable the subject to advance from household ambulation to limited community ambulation. Additionally, the subject could perform multiple walks per day when using FES-assisted gait, which was impossible with volitional effort alone.

  19. Clinical evaluation of short 6-mm implants alone, short 8-mm implants combined with osteotome sinus floor elevation and standard 10-mm implants combined with osteotome sinus floor elevation in posterior maxillae: study protocol for a randomized controlled trial

    OpenAIRE

    Shi, Jun-Yu; Gu, Ying-Xin; Qiao, Shi-Chong; Zhuang, Long-Fei; Zhang, Xiao-Meng; Lai, Hong-Chang

    2015-01-01

    Background Nowadays, short dental implants are being increasingly applied in extremely resorbed posterior regions. The recent studies have indicated that short implants present a similar success rate to conventional implants. It is assumed that short implants can avoid additional surgical morbidity and are less technically demanding. However, high-quality evidence (≥Ib: evidence from at least one randomized controlled trial) on comparing the clinical outcome of short implants and longer impla...

  20. Pre-implant right ventricular function might be an important predictor of the response to cardiac resynchronization therapy

    Directory of Open Access Journals (Sweden)

    Ring Margareta

    2011-10-01

    Full Text Available Abstract Objective Cardiac resynchronization therapy is proven efficacious in patients with heart failure (HF. Presence of biventricular HF is associated with a worse prognosis than having only left ventricular (LV HF and pacing might deteriorate heart function. The aim of the study was to assess a possible significance of right ventricular (RV pre-implant systolic function to predict response to CRT. Design We studied 22 HF-patients aged 72 ± 11 years, QRS-duration 155 ± 20 ms and with an LV ejection fraction (EF of 26 ± 6% before and four weeks after receiving a CRT-device. Results There were no changes in LV diameters or end systolic volume (ESV during the study. However, end diastolic volume (EDV decreased from 226 ± 71 to 211 ± 64 ml (p = 0.02 and systolic maximal velocities (SMV increased from 2.2 ± 0.4 to 2.6 ± 0.9 cm/s (p = 0.04. Pre-implant RV-SMV (6.2 ± 2.6 cm/s predicted postoperative increase in LV contractility, p = 0.032. Conclusions Pre-implant decreased RV systolic function might be an important way to predict a poor response to CRT implicating that other treatments should be considered. Furthermore we found that 3D- echocardiography and Tissue Doppler Imaging were feasible to detect short-term changes in LV function.

  1. Implants delivering bisphosphonate locally increase periprosthetic bone density in an osteoporotic sheep model. A pilot study

    Directory of Open Access Journals (Sweden)

    GVA Stadelmann

    2008-07-01

    Full Text Available It is a clinical challenge to obtain a sufficient orthopaedic implant fixation in weak osteoporotic bone. When the primary implant fixation is poor, micromotions occur at the bone-implant interface, activating osteoclasts, which leads to implant loosening. Bisphosphonate can be used to prevent the osteoclastic response, but when administered systemically its bioavailability is low and the time it takes for the drug to reach the periprosthetic bone may be a limiting factor. Recent data has shown that delivering bisphosphonate locally from the implant surface could be an interesting solution. Local bisphosphonate delivery increased periprosthetic bone density, which leads to a stronger implant fixation, as demonstrated in rats by the increased implant pullout force. The aim of the present study was to verify the positive effect on periprosthetic bone remodelling of local bisphosphonate delivery in an osteoporotic sheep model. Four implants coated with zoledronate and two control implants were inserted in the femoral condyle of ovariectomized sheep for 4 weeks. The bone at the implant surface was 50% higher in the zoledronate-group compared to control group. This effect was significant up to a distance of 400µm from the implant surface. The presented results are similar to what was observed in the osteoporotic rat model, which suggest that the concept of releasing zoledronate locally from the implant to increase the implant fixation is not species specific. The results of this trial study support the claim that local zoledronate could increase the fixation of an implant in weak bone.

  2. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Rhoodie Garrana

    2016-01-01

    Full Text Available Background. Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives. (i To determine if endotoxin can traverse different implant-abutment connection (IAC designs; (ii to quantify the amount of endotoxins traversing the IAC; (iii to compare the in vitro comportments of different IACs. Materials and Methods. Twenty-seven IACs were inoculated with E. coli endotoxin. Six of the twenty-seven IACs were external connections from one system (Southern Implants and the remaining twenty-one IACs were made up of seven internal IAC types from four different implant companies (Straumann, Ankylos, and Neodent, Southern Implants. Results. Of the 27 IACs tested, all 6 external IACs leaked measurable amounts of endotoxin. Of the remaining 21 internal IACs, 9 IACs did not show measurable leakage whilst the remaining 12 IACs leaked varying amounts. The mean log endotoxin level was significantly higher for the external compared to internal types (p=0.015. Conclusion. Within the parameters of this study, we can conclude that endotoxin leakage is dependent on the design of the IAC. Straumann Synocta, Straumann Cross-fit, and Ankylos displayed the best performances of all IACs tested with undetectable leakage after 7 days. Each of these IACs incorporated a morse-like component in their design. Speculation still exists over the impact of IAC endotoxin leakage on peri-implant tissues in vivo; hence, further investigations are required to further explore this.

  3. Leakage of Microbial Endotoxin through the Implant-Abutment Interface in Oral Implants: An In Vitro Study.

    Science.gov (United States)

    Garrana, Rhoodie; Mohangi, Govindrau; Malo, Paulo; Nobre, Miguel

    2016-01-01

    Background. Endotoxin initiates osteoclastic activity resulting in bone loss. Endotoxin leakage through implant abutment connections negatively influences peri-implant bone levels. Objectives. (i) To determine if endotoxin can traverse different implant-abutment connection (IAC) designs; (ii) to quantify the amount of endotoxins traversing the IAC; (iii) to compare the in vitro comportments of different IACs. Materials and Methods. Twenty-seven IACs were inoculated with E. coli endotoxin. Six of the twenty-seven IACs were external connections from one system (Southern Implants) and the remaining twenty-one IACs were made up of seven internal IAC types from four different implant companies (Straumann, Ankylos, and Neodent, Southern Implants). Results. Of the 27 IACs tested, all 6 external IACs leaked measurable amounts of endotoxin. Of the remaining 21 internal IACs, 9 IACs did not show measurable leakage whilst the remaining 12 IACs leaked varying amounts. The mean log endotoxin level was significantly higher for the external compared to internal types (p = 0.015). Conclusion. Within the parameters of this study, we can conclude that endotoxin leakage is dependent on the design of the IAC. Straumann Synocta, Straumann Cross-fit, and Ankylos displayed the best performances of all IACs tested with undetectable leakage after 7 days. Each of these IACs incorporated a morse-like component in their design. Speculation still exists over the impact of IAC endotoxin leakage on peri-implant tissues in vivo; hence, further investigations are required to further explore this.

  4. Effects of local administration of growth hormone in peri-implant bone: an experimental study with implants in rabbit tibiae.

    Science.gov (United States)

    Tresguerres, Isabel F; Blanco, Luis; Clemente, Celia; Tresguerres, Jesús A F

    2003-01-01

    The objective of this study was to evaluate the qualitative and quantitative differences that could appear in newly formed peri-implant bone around Screw-Vent implants placed in rabbit tibiae when treated with local administration of growth hormone (GH). Eight New Zealand rabbits were randomly divided into 2 groups: the experimental group, which received 4 IU of GH in the form of lyophilized powder added to the ostectomy site before implant placement, and the control group, which did not receive GH before implant placement. Animals were sacrificed 2 weeks later, and histologic sections were obtained for histomorphometry and observation under light microscopy. The sections in the GH-treated group presented enhanced growth of new trabeculae from the periosteal tissue, and the bone-to-implant contact in the experimental group was significantly greater (P < .05). Local administration of GH stimulated a more dramatic effect than that seen previously with systemic GH administration, prompting growth from both the periosteum and endosteum. Local administration of GH at the time of implant placement could enhance peri-implant bone reaction.

  5. Magnetic resonance imaging investigation of the bone conduction implant – a pilot study at 1.5 Tesla

    Science.gov (United States)

    Jansson, Karl-Johan Fredén; Håkansson, Bo; Reinfeldt, Sabine; Rigato, Cristina; Eeg-Olofsson, Måns

    2015-01-01

    Purpose The objective of this pilot study was to investigate if an active bone conduction implant (BCI) used in an ongoing clinical study withstands magnetic resonance imaging (MRI) of 1.5 Tesla. In particular, the MRI effects on maximum power output (MPO), total harmonic distortion (THD), and demagnetization were investigated. Implant activation and image artifacts were also evaluated. Methods and materials One implant was placed on the head of a test person at the position corresponding to the normal position of an implanted BCI and applied with a static pressure using a bandage and scanned in a 1.5 Tesla MRI camera. Scanning was performed both with and without the implant, in three orthogonal planes, and for one spin-echo and one gradient-echo pulse sequence. Implant functionality was verified in-between the scans using an audio processor programmed to generate a sequence of tones when attached to the implant. Objective verification was also carried out by measuring MPO and THD on a skull simulator as well as retention force, before and after MRI. Results It was found that the exposure of 1.5 Tesla MRI only had a minor effect on the MPO, ie, it decreased over all frequencies with an average of 1.1±2.1 dB. The THD remained unchanged above 300 Hz and was increased only at lower frequencies. The retention magnet was demagnetized by 5%. The maximum image artifacts reached a distance of 9 and 10 cm from the implant in the coronal plane for the spin-echo and the gradient-echo sequence, respectively. The test person reported no MRI induced sound from the implant. Conclusion This pilot study indicates that the present BCI may withstand 1.5 Tesla MRI with only minor effects on its performance. No MRI induced sound was reported, but the head image was highly distorted near the implant. PMID:26604836

  6. Magnetic resonance imaging investigation of the bone conduction implant - a pilot study at 1.5 Tesla.

    Science.gov (United States)

    Jansson, Karl-Johan Fredén; Håkansson, Bo; Reinfeldt, Sabine; Rigato, Cristina; Eeg-Olofsson, Måns

    2015-01-01

    The objective of this pilot study was to investigate if an active bone conduction implant (BCI) used in an ongoing clinical study withstands magnetic resonance imaging (MRI) of 1.5 Tesla. In particular, the MRI effects on maximum power output (MPO), total harmonic distortion (THD), and demagnetization were investigated. Implant activation and image artifacts were also evaluated. One implant was placed on the head of a test person at the position corresponding to the normal position of an implanted BCI and applied with a static pressure using a bandage and scanned in a 1.5 Tesla MRI camera. Scanning was performed both with and without the implant, in three orthogonal planes, and for one spin-echo and one gradient-echo pulse sequence. Implant functionality was verified in-between the scans using an audio processor programmed to generate a sequence of tones when attached to the implant. Objective verification was also carried out by measuring MPO and THD on a skull simulator as well as retention force, before and after MRI. It was found that the exposure of 1.5 Tesla MRI only had a minor effect on the MPO, ie, it decreased over all frequencies with an average of 1.1±2.1 dB. The THD remained unchanged above 300 Hz and was increased only at lower frequencies. The retention magnet was demagnetized by 5%. The maximum image artifacts reached a distance of 9 and 10 cm from the implant in the coronal plane for the spin-echo and the gradient-echo sequence, respectively. The test person reported no MRI induced sound from the implant. This pilot study indicates that the present BCI may withstand 1.5 Tesla MRI with only minor effects on its performance. No MRI induced sound was reported, but the head image was highly distorted near the implant.

  7. Functional brain fluorescence plurimetry in rat by implantable concatenated CMOS imaging system.

    Science.gov (United States)

    Kobayashi, Takuma; Masuda, Hiroyuki; Kitsumoto, Chikara; Haruta, Makito; Motoyama, Mayumi; Ohta, Yasumi; Noda, Toshihiko; Sasagawa, Kiyotaka; Tokuda, Takashi; Shiosaka, Sadao; Ohta, Jun

    2014-03-15

    Measurement of brain activity in multiple areas simultaneously by minimally invasive methods contributes to the study of neuroscience and development of brain machine interfaces. However, this requires compact wearable instruments that do not inhibit natural movements. Application of optical potentiometry with voltage-sensitive fluorescent dye using an implantable image sensor is also useful. However, the increasing number of leads required for the multiple wired sensors to measure larger domains inhibits natural behavior. For imaging broad areas by numerous sensors without excessive wiring, a web-like sensor that can wrap the brain was developed. Kaleidoscopic potentiometry is possible using the imaging system with concatenated sensors by changing the alignment of the sensors. This paper describes organization of the system, evaluation of the system by a fluorescence imaging, and finally, functional brain fluorescence plurimetry by the sensor. The recorded data in rat somatosensory cortex using the developed multiple-area imaging system compared well with electrophysiology results.

  8. Relation of statin therapy to psychological functioning in patients with an implantable cardioverter defibrillator

    DEFF Research Database (Denmark)

    Hoogwegt, Madelein T; Theuns, Dominic A M J; Kupper, Nina

    2013-01-01

    Statin therapy is an important secondary prevention measure in cardiovascular disease. However, the side effects associated with statin use could potentially affect patients' quality of life. Little is known about the influence of statin therapy on the well-being and health status of cardiac...... patients, in general, and patients with an implantable cardioverter defibrillator (ICD), in particular. We investigated the association between statin therapy and symptoms of anxiety and depression and patients' health status during the 12 months after implantation, reckoning with statin type and dosage....... Consecutively implanted ICD patients (n = 409; 78.2% men) completed the Hospital Anxiety and Depression Scale and the Medical Outcomes Study Short Form 36-item Health Survey at baseline and 3, 6, and 12 months after implantation. The data were analyzed using general linear mixed modeling repeated measures...

  9. Los implantes MG-OSSEOUS: Estudio multicéntrico retrospectivo MG-OSSEOUS implants: A multicentric retrospective study

    Directory of Open Access Journals (Sweden)

    E. Serrano Caturla

    2006-12-01

    commercial implants. Material and methodology. This is a retrospective multicentric study coordinated by a company called Scientific Management in O&SS (Barcelona, Spain. 1001 dental implants were placed in 247 patients and 328 prostheses were designed between 2004 and 2005, with a follow-up of two years. All implants were loaded with prostheses. We detail and analyze each implant, according to the diameter, length, position, surgical timing, loadings, design and types of prostheses and complementary surgical procedures, either synchronic or metachronic. Results. After the statistical method was homogenized, we were able to report an overall implant survival rate of 97.8% with monitoring of two years. The failures depending on the peculiarities of each clinical case are provided. No prosthetic failures are reported. Discussion. The criteria and indications applied by the professionals to the MG-OSSEOUS implants are standardized depending on the clinical case. Our results are compared with the international scientific literature, past and present, with these procedures totally agreeing with those found in the history of implantology. Finally, our survey is compared with those published by the Branemark team. Conclusion. The mixture between the quality of the MGOSSEOUS implants and the scientifically supported criteria regarding the implants, reveals an implant failure of 2.2% over two years, with a survival of 100% of both the replaced implants and the loaded prostheses.

  10. A study of the bone healing kinetics of plateau versus screw root design titanium dental implants.

    LENUS (Irish Health Repository)

    Leonard, Gary

    2009-03-01

    This study was designed to compare the bone healing process around plateau root from (PRF) and screw root from (SRF) titanium dental implants over the immediate 12 week healing period post implant placement.

  11. Studying Herpesvirus Pathogenesis Using SCID Mice Implanted With Human Tissues

    Institute of Scientific and Technical Information of China (English)

    Marvin; Sommer; Shannon; Taylor; Stacey; Leisenfelder; Robert; Morton; Ann; Arvin; Jennifer; Moffat

    2005-01-01

    Human cytomegalovirus(HCMV)and Varicella Zoster virus(VZV)are belongto herpesvirusfamily.HCMVrarelycaus-es symptomatic diseaseinanimmunocompetent host;however,itis a major cause of infectious morbidityand mortalityinimmunocompromised individuals and developingfetuses.VZVinfectioncauses chickenpoxandshingles.Sincethese spe-cies-specific herpesviruses do notinfect other animals,noanimal model is availablefor pathogenesis studies.Severe com-binedimmunodeficient(SCID)mice implanted with humantissues(SCID-hu)pro...

  12. A cross-sectional study on the prevalence of marginal bone loss among implant patients.

    Science.gov (United States)

    Cecchinato, Denis; Parpaiola, Andrea; Lindhe, Jan

    2013-01-01

    The aim of the present cross-sectional retrospective study was to determine bone loss in a sample of subjects restored with implant-supported prostheses and the prevalence and severity of peri-implantitis in a sub-sample. A total of 139 patients who had attended a follow-up visit in 2007 were considered for inclusion. Subjects with implants that had been in function for less than 3 years or had poor quality radiographs were excluded. The final study population comprised 133 subjects with a total of 407 implants. Radiographic measurements identified subjects who had ≥1 implant site exhibiting marginal bone loss of >0.5 mm; 40 subjects met this criterion and were recalled for a clinical examination. Of the 40 subjects that were recalled for the clinical examination, 30 attended. The following parameters were recorded at mesial, distal, buccal, and lingual/palatal aspects of all implants: oral hygiene standard (plaque), bleeding on probing, probing pocket depth (PPD). The mean interval between the baseline (1-year post-loading) and the follow-up radiographs was 4.8 ± 2.3 years. In the total subject sample (133 subjects and 407 implants), the mean amount of marginal bone loss that had occurred was 0.2 ± 1.2 mm. Ninety-three subjects with 246 implant sites exhibited no bone level alteration (group A), whereas 40 subjects with 161 implant sites (group B) displayed marginal bone loss of >0.5 mm at ≥1 implant (loser site). Sixty-eight implant sites in group B exhibited bone loss of >0.5 mm. However, only 20% of subjects and 11% of sites had lost >1 mm marginal bone, and 8% of subjects and 4% of sites had lost >2 mm bone. The total amount of bone loss that had occurred in group B was (i) 0.88 ± 1.5 mm and (ii) among the loser sites 2.1 ± 1.4 mm. Thirty subjects from group B were exposed to a clinical examination; out of 37 sites with bone loss >0.5 mm in this subgroup, 29 sites had a PPD value of ≥4 mm. Marginal bone loss (>0.5 mm) at implants

  13. Evaluation of bone loss in antibacterial coated dental implants: An experimental study in dogs.

    Science.gov (United States)

    Godoy-Gallardo, Maria; Manzanares-Céspedes, Maria Cristina; Sevilla, Pablo; Nart, José; Manzanares, Norberto; Manero, José M; Gil, Francisco Javier; Boyd, Steven K; Rodríguez, Daniel

    2016-12-01

    The aim of this study was to evaluate the in vivo effect of antibacterial modified dental implants in the first stages of peri-implantitis. Thirty dental implants were inserted in the mandibular premolar sites of 5 beagle dogs. Sites were randomly assigned to Ti (untreated implants, 10units), Ti_Ag (silver electrodeposition treatment, 10units), and Ti_TSP (silanization treatment, 10units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated by ligature placement. Ligatures were removed 2months later, and plaque formation was allowed for 2 additional months. Clinical and radiographic analyses were performed during the study. Implant-tissue samples were prepared for micro computed tomography, backscattered scanning electron microscopy, histomorphometric and histological analyses and ion release measurements. X-ray, SEM and histology images showed that vertical bone resorption in treated implants was lower than in the control group (Pimplant surface. Histological analysis suggested an increase of peri-implant bone formation on silanized implants. However, the short post-ligature period was not enough to detect differences in clinical parameters among implant groups. Within the limits of this study, antibacterial surface treatments have a positive effect against bone resorption induced by peri-implantitis. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Ellipsometric study of crystalline silicon hydrogenated by plasma immersion ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Szekeres, A. [Institute of Solid State Physics, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia (Bulgaria); Alexandrova, S. [Department of Applied Physics, Technical University of Sofia, Kl. Ohridski 8, 1797 Sofia (Bulgaria); Petrik, P., E-mail: petrik@mfa.kfki.hu [MFA Institute for Technical Physics and Materials Science, TTK Research Centre for Natural Sciences, Konkoly Thege Rd. 29-33, 1121 Budapest (Hungary); Fodor, B. [MFA Institute for Technical Physics and Materials Science, TTK Research Centre for Natural Sciences, Konkoly Thege Rd. 29-33, 1121 Budapest (Hungary); Bakalova, S. [Institute of Solid State Physics, 72 Tzarigradsko Chaussee Blvd., 1784 Sofia (Bulgaria)

    2013-09-15

    The structure and the optical properties of thin Si layer hydrogenated by shallow plasma ion implantation with different fluences up to 10{sup 15} cm{sup −2} are studied using spectroscopic ellipsometry and simulation of the distributions of the ions and implantation induced defects. The implantation was regarded to proceed into Si through the native SiO{sub 2}. Two-layer optical models are applied for examination of the composition and dielectric function behavior of the formed structures. The native oxide is found to be 3 nm thick. The thickness of the Si modified layer decreased 23 to 14 nm with ion fluence due to increased formation of highly hydrogenated surface region that hinder further H-penetration into the Si bulk, especially at the highest fluence. Shifts of the features in the obtained dielectric functions related with Si interband transitions at about 3.4 and 4.2 eV are found caused by process-induced tensile stress. The modified Si region is related rather to defects created by the ion implantation process than the projected range of hydrogen ions. The overall layer modification can be characterized by a low degree of amorphization (up to 5.8%), creation of structural defects and internal tensile stress.

  15. Biocompatibility and biodegradation studies of subconjunctival implants in rabbit eyes.

    Directory of Open Access Journals (Sweden)

    Yan Peng

    Full Text Available Sustained ocular drug delivery is difficult to achieve. Most drugs have poor penetration due to the multiple physiological barriers of the eye and are rapidly cleared if applied topically. Biodegradable subconjunctival implants with controlled drug release may circumvent these two problems. In our study, two microfilms (poly [d,l-lactide-co-glycolide] PLGA and poly[d,l-lactide-co-caprolactone] PLC were developed and evaluated for their degradation behavior in vitro and in vivo. We also evaluated the biocompatibility of both microfilms. Eighteen eyes (9 rabbits were surgically implanted with one type of microfilm in each eye. Serial anterior-segment optical coherence tomography (AS-OCT scans together with serial slit-lamp microscopy allowed us to measure thickness and cross-sectional area of the microfilms. In vitro studies revealed bulk degradation kinetics for both microfilms, while in vivo studies demonstrated surface erosion kinetics. Serial slit-lamp microscopy revealed no significant inflammation or vascularization in both types of implants (mean increase in vascularity grade PLGA50/50 12±0.5% vs. PLC70/30 15±0.6%; P = 0.91 over a period of 6 months. Histology, immunohistochemistry and immuno-fluorescence also revealed no significant inflammatory reaction from either of the microfilms, which confirmed that both microfilms are biocompatible. The duration of the drug delivery can be tailored by selecting the materials, which have different degradation kinetics, to suit the desired clinical therapeutic application.

  16. Executive Functioning and Speech-Language Skills Following Long-Term Use of Cochlear Implants

    Science.gov (United States)

    Kronenberger, William G.; Colson, Bethany G.; Henning, Shirley C.; Pisoni, David B.

    2014-01-01

    Neurocognitive processes such as executive functioning (EF) may influence the development of speech-language skills in deaf children after cochlear implantation in ways that differ from normal-hearing, typically developing children. Conversely, spoken language abilities and experiences may also exert reciprocal effects on the development of EF.…

  17. Executive Functioning and Speech-Language Skills Following Long-Term Use of Cochlear Implants

    Science.gov (United States)

    Kronenberger, William G.; Colson, Bethany G.; Henning, Shirley C.; Pisoni, David B.

    2014-01-01

    Neurocognitive processes such as executive functioning (EF) may influence the development of speech-language skills in deaf children after cochlear implantation in ways that differ from normal-hearing, typically developing children. Conversely, spoken language abilities and experiences may also exert reciprocal effects on the development of EF.…

  18. DLTS and EPR study of defects in H implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Miksic, V.; Pivac, B. E-mail: pivac@rudjer.irb.hr; Rakvin, B.; Zorc, H.; Corni, F.; Tonini, R.; Ottaviani, G

    2002-01-01

    Single crystal CZ Si samples were implanted with hydrogen ions to the dose of 2E16 He ions/cm{sup 2} at room temperature and subsequently annealed in vacuum in the temperature interval from 100 to 900 deg. C. The aim of the experiment was to determine the conditions for bubble formation within the solid film, which may have important technological application. Defects produced in such samples were studied by deep-level transient spectroscopy (DLTS) and electron paramagnetic resonance (EPR) spectroscopy. It is shown that high dose hydrogen implantation produces vacancy-related and silicon selfinterstitial clusters. The latter are thought to be responsible for the formation of the weak displacement field. The annealing at higher temperatures creates multivacancy-related clusters responsible for the strong displacement field formation.

  19. Application of Functional Nano-Patterning to Polymer Medical Micro Implants

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Biondani, Francesco Giuseppe; Tang, P.T.;

    2015-01-01

    Improvement of cells adhesion to medical implants can be achieved through specific surface nano-patterns. The application of nano-patterns to planar surfaces can be obtained in a number of ways. However, the application of functional nano-patterns to complex 3D surfaces is a challenging task....... In this paper the application of a nano-pattern deriving from aluminium anodizing to 3D micro mould inserts for replication of polymer medical micro implants is described. A process chain earlier developed at DTU was applied, where the main steps include the fabrication of an aluminium master, anodizing...

  20. Impaired Vestibular Function After Cochlear Implantation in Children: Role of Static Posturography.

    Science.gov (United States)

    Nair, Satish; Gupta, Atul; Nilakantan, Ajith; Mittal, Ruchika; Dahiya, Ruchi; Saini, Sachin; Prasad, Rachana; Vajpayee, Deepika

    2017-06-01

    To identify vestibular dysfunction in children after cochlear implant surgery and to study the utility of static posturography in evaluating vestibular function in children. A prospective study was carried out on 25 children between 2 and 7 years of age with sensorineural hearing loss with no overt vestibular dysfunction. All children underwent static posturography using Synapsis Posturographic System (SPS) software (Version 3.0, REV C) using a static platform with foam. The centre of pressure (COP) shift was recorded as statokinesiogram on the software and the mean vestibular, visual and somesthetic scores were obtained. Cochlear implantation (CI) surgery was done with insertion of Med-El Pulsar standard cochlear implant with 12 twin electrodes. Children were evaluated again after 4 weeks of CI surgery (2 weeks after switch on) with static posturography on the same SPS software. The scores obtained were compared with pre op value and data analyzed statistically by paired t tests on SPSS 18 software. The mean age was 4.6 years with range 2-7 years. All the children in the study were able to complete the test with no difficulty and the mean time required for each child was 10.2 min. The mean pre op somesthetic score was 95.16 (SD 1.52) and post op score was 94.06 (SD 1.79). The mean pre op visual score was 86.64 (SD 2.24) and post op score was 82.55 (2.89). The mean pre op vestibular score was 84.11 (SD 2.20) and post op score was 73.66 (SD 4.25). Correlation and statistical analysis of the pre and post values of each score revealed statistically significant reduction in vestibular scores post CI. The vestibular system is at high risk of injury leading to vestibular dysfunction in children during CI. Our study found the static posturography as a simple, fast and efficient tool to screen children for vestibular dysfunction post CI. Identifying the dysfunction early can help in initiating early rehabilitation measures.

  1. Clinical and radiographic evaluation of single tantalum dental implants: a prospective pilot clinical study

    Science.gov (United States)

    DE FRANCESCO, M.; GOBBATO, E.A.; NOCE, D.; CAVALLARI, F.; FIORETTI, A.

    2016-01-01

    SUMMARY Objective The aim of this prospective pilot clinical case series report was to evaluate, through a clinical and radiographic analysis, the peri-implant bone resorption of the tantalum dental implants (TMT) (Zimmer TMT, Parsippany, NJ, USA) one year after prosthetic rehabilitation. Methods Twenty tantalum dental implants were placed in both maxillas and mandibles of 20 patients. Patients were asked to attend a radiographic and clinical follow-up and their previous clinical records and X-rays were assessed. Bone levels were calculated by digitally measuring the distance from the implant shoulder to the first bone-to-implant on periapical radiographs taken at surgery and after 6 and 12 months of functioning. The Pearson correlation analysis was performed to assess it there was a correlation between the measurement of the marginal bone loss (MBL). The Anova Test with a post-hoc analysis using Bonferroni’s test was used to compare the three group (0, 6 months and 12 months). Results The mean total MBL for the group 0 months was 0.84 mm (SD 0.21), 6 months was 0.87 mm (SD 0.22) and for 12 months was 0.89 mm (SD 0.23). The values of the Pearson’s coefficients showed that the data measurement were positively correlated. The Anova test showed a statistically significant difference between the groups. Conclusion The statistically significant difference in marginal bone loss can be considered physiological. Within the limits of this study it can be concluded that TMT implants have an excellent bone crest’s stability, however, to have most accurate information, will be necessary extend the sample. PMID:28280531

  2. One-step surgical placement of Brånemark implants: a prospective multicenter clinical study.

    Science.gov (United States)

    Becker, W; Becker, B E; Israelson, H; Lucchini, J P; Handelsman, M; Ammons, W; Rosenberg, E; Rose, L; Tucker, L M; Lekholm, U

    1997-01-01

    This prospective longitudinal multicenter study evaluated the clinical outcomes after placement and restoration of one-step Brånemark implants into the maxillae and mandibles of completely and partially edentulous patients. Six surgical treatment centers participated in this study, in which 135 implants were placed into 63 adult patients. All implants were stable after placement. The majority of implants were placed into type B bone with minimal jaw resorption and type 2 bone quality. After implant placement, standard transmucosal healing abutments were firmly placed. The average amount of time between implant placement and prosthetic abutment connection was 170 days in the maxillae and 147 days in the mandibles. To evaluate crestal bone changes caused by implant placement, a periodontal probe was used to measure midbuccally from the top of the implant cylinder to the alveolar crest; in 29 patients, 54 midbuccal bone crest sites were remeasured following prosthetic abutment connection. Crestal bone changes in mandibles and maxillae were statistically and clinically insignificant. Six implants were lost prior to loading and one implant has not been restored. No implants or restorations were lost after loading. At 1 year, the implant success rate was 95.6%. Mesiodistal radiographic measurements from 34 patients were averaged, and changes from prosthetic abutment connection to, on average, 12 months follow-up were compared. The radiographs, which were digitalized, measured from the bottom of the implant cylinder to the most coronal bone in contact with implant thread. For mandibular implants, the mean radiographic bone level at prosthetic abutment connection was 1.07 mm; after loading, it was 1.35 mm. For maxillary implants, the mean radiographic bone height at prosthetic abutment connection was 1.16 mm; after loading, it was 1.36 mm. These changes were not statistically significant. The 1-year outcomes from this patient series indicate that one-step Br

  3. In vitro study of reduction of stress transferred onto tissues around implants using a resilient material in maxillary implant overdentures.

    Science.gov (United States)

    Kanazawa, Manabu; Minakuchi, Shunsuke; Hayakawa, Iwao; Hirano, Shigezo; Uchida, Tatsuro

    2007-03-01

    The purpose of this in vitro study was to investigate the effect of hardness on the reduction of stress transferred to tissues around implants using a resilient material applied to the female parts of the ball attachment in maxillary implant overdentures. A cast chrome-cobalt framework was mounted onto a maxillary acrylic edentulous model, which contained two implants and four strain gauges attached to the implant. Ball abutments were screwed into the implant. One abutment was connected to a dedicated metal cap embedded in the housing, while the others were connected to resilient test materials with four different hardnesses. Loads were applied using a universal testing machine with a magnitude of 50 N. The sums of the absolute values recorded from the four strain gauges were used for stress evaluation. The measured strains were analyzed statistically using two-way ANOVA and multiple comparisons. A resilient material with hardness 90 exhibited strains that did not differ significantly from the control. In contrast, the other resilient materials showed significantly reduced strains under all conditions. In this limited study, application of resilient silicone materials with approximate hardness 80 to the female parts of ball attachments significantly reduced the stress on the tissues around the implant.

  4. Evaluation of bone loss in antibacterial coated dental implants: An experimental study in dogs

    DEFF Research Database (Denmark)

    Gallardo, Maria Godoy; Manzanares-Céspedes, Maria Cristina; Sevilla, Pablo

    2016-01-01

    The aim of this study was to evaluate the in vivo effect of antibacterial modified dental implants in the first stages of peri-implantitis. Thirty dental implants were inserted in the mandibular premolar sites of 5 beagle dogs. Sites were randomly assigned to Ti (untreated implants, 10 units), Ti......_Ag (silver electrodeposition treatment, 10 units), and Ti_TSP (silanization treatment, 10 units). Coated implants were characterized by scanning electron microscopy, interferometry and X-ray photoelectron spectroscopy. Two months after implant insertion, experimental peri-implantitis was initiated...... by ligature placement. Ligatures were removed 2 months later, and plaque formation was allowed for 2 additional months. Clinical and radiographic analyses were performed during the study. Implant-tissue samples were prepared for micro computed tomography, backscattered scanning electron microscopy...

  5. Nanofibers implant functionalized by neural growth factor as a strategy to innervate a bioengineered tooth.

    Science.gov (United States)

    Eap, Sandy; Bécavin, Thibault; Keller, Laetitia; Kökten, Tunay; Fioretti, Florence; Weickert, Jean-Luc; Deveaux, Etienne; Benkirane-Jessel, Nadia; Kuchler-Bopp, Sabine

    2014-03-01

    Current strategies for jaw reconstruction require multiple procedures, to repair the bone defect, to offer sufficient support, and to place the tooth implant. The entire procedure can be painful and time-consuming, and the desired functional repair can be achieved only when both steps are successful. The ability to engineer combined tooth and bone constructs, which would grow in a coordinated fashion with the surrounding tissues, could potentially improve the clinical outcomes and also reduce patient suffering. A unique nanofibrous and active implant for bone-tooth unit regeneration and also the innervation of this bioengineered tooth are demonstrated. A nanofibrous polycaprolactone membrane is functionalized with neural growth factor, along with dental germ, and tooth innervation follows. Such innervation allows complete functionality and tissue homeostasis of the tooth, such as dentinal sensitivity, odontoblast function, masticatory forces, and blood flow.

  6. Microbial Characteristics of Peri-Implantitis : A Case-Control Study

    NARCIS (Netherlands)

    de Waal, Y C M; Eijsbouts, H V L C; Winkel, E G; van Winkelhoff, A J

    2016-01-01

    BACKGROUND: Aim of this case-control study was to compare oral microbiological characteristics of subjects with healthy peri-implant conditions and subjects with peri-implantitis and to explore the influence of various patient-related and implant-related factors on the microbiological characteristic

  7. Microbial Characteristics of Peri-Implantitis : A Case-Control Study

    NARCIS (Netherlands)

    de Waal, Y C M; Eijsbouts, H V L C; Winkel, E G; van Winkelhoff, A J

    BACKGROUND: Aim of this case-control study was to compare oral microbiological characteristics of subjects with healthy peri-implant conditions and subjects with peri-implantitis and to explore the influence of various patient-related and implant-related factors on the microbiological

  8. Speckle-Tracking Echocardiographic Measures of Right Ventricular Function Correlate With Improvement in Exercise Function After Percutaneous Pulmonary Valve Implantation.

    Science.gov (United States)

    Chowdhury, Shahryar M; Hijazi, Ziyad M; Fahey, John T; Rhodes, John F; Kar, Saibal; Makkar, Raj; Mullen, Michael; Cao, Qi-Ling; Shirali, Girish S

    2015-09-01

    Speckle-tracking echocardiographic (STE) measures of right ventricular (RV) function appear to improve after transcatheter pulmonary valve implantation (TPVI). Measures of exercise function, such as ventilatory efficiency (the minute ventilation [VE]/carbon dioxide production [VCO2] slope), have been shown to be prognostic of mortality in patients who may require TPVI. The aim of this study was to evaluate the correlation between STE measures of RV function and changes in VE/VCO2 after TPVI. Speckle-tracking echocardiography and cardiopulmonary exercise testing were performed at baseline and 6 months after TPVI in 24 patients from four centers. Conventional echocardiographic measures of RV function were also assessed. Echocardiographic and exercise stress test results were interpreted by single blinded observers at separate core laboratories. All patients demonstrated relief of pulmonary regurgitation and stenosis after TPVI. Improvements in RV longitudinal strain (-16.9 ± 3.5% vs -19.7 ± 4.3%, P rate (-0.9 ± 0.4 vs. -1.2 ± 0.4 s(-1), P exercise changes were found. On multivariate regression, the change in VE/VCO2 was independently associated with change in RV longitudinal early diastolic strain rate (P change in VE/VCO2 after TPVI (r = -0.60, P < .001). STE measures of RV function appear to hold the potential for use as predictors of improved outcomes in patients requiring TPVI. Future studies should directly assess the prognostic significance of STE measures of RV function in this population. Copyright © 2015 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  9. Preoperative Echocardiography Examination of Right Ventricle Function in Patients Scheduled for LVAD Implantation Correlates with Postoperative Hemodynamic Examinations.

    Science.gov (United States)

    Nadziakiewicz, Paweł; Niklewski, Tomasz; Szyguła-Jurkiewicz, Bożena; Pacholewicz, Jerzy; Zakliczyński, Michał; Borkowski, Jarosław; Hrapkowicz, Tomasz; Zembala, Marian

    2016-08-11

    BACKGROUND Left ventricular assist devices (LVAD) are used to treat heart failure. Preoperative prediction of RV function after LVAD implantation is crucial. Correlations were found between preoperative echo and RV function after LVAD implantation. MATERIAL AND METHODS We retrospectively reviewed 23 male patients (8 ischemic, 15 nonischemic cardiomyopathy) with LVAD implantation (17 HeartWare, 6 HeartMate II) at the Silesian Center for Heart Diseases from 1 January 2013 to 28 October 2014. Preoperative TTE data of RV function included RVFAC (fractional area change), TAPSE (tricuspid annulus plane systolic excursion), RV diameter (RV4), and RV/LV (right/left ventricle) ratio. Postoperative hemodynamic mean pulmonary pressure (mPAP), central venous pressure (CVP), cardiac output (CO), and cardiac index (CI) were measured and recorded every 2 h up to 10 days (1, 2, …120) and correlated. Study endpoints were mortality, discharge from ICU, and RV dysfunction. RESULTS There were no RV dysfunctions. Correlations of CO and CI with RV4 and RV/LV ratio were significantly positive at many time points, with TAPSE and FAC positive or negative. Correlations mPAP with RV4 were significantly positive: 1, 2, 3, 7, 8, 57, 58, 59. With RV/LV ratio positive: 44, 47, with TAPSE in 36. With FAC positive 11, 13-15, 22 and negative 57. Correlations CVP with RV4 were negative, with positive significance in 1, 52. With RV/LV ratio positively 52, 54, 56 and negative 71, 72, 73. With TAPSE were negative significantly: 30, 68. With FAC positive 11, 12, 13, 14 and negative: 68. CONCLUSIONS RV4 and RV/LV ratio before LVAD implantation are more predictive for postoperative RV function than RVFAC and TAPSE, probably because RVFAC and TAPSE are load-dependent.

  10. How to test mode switching in pacemakers implanted in patients: the MOST study.

    Science.gov (United States)

    Padeletti, Luigi; Gasparini, Maurizio; Porciani, Maria Cristina; Pieragnoli, Paolo; Colella, Andrea; Michelucci, Antonio; Proclemer, Alessandro; Tognarini, Stefano; Mantica, Massimo; Coltorti, Fernando; Corbucci, Giorgio; Sutton, Richard

    2002-02-01

    Optimal management of atrial arrhythmias with dual chamber pacemakers requires proper performance of automatic mode switching (AMS). The aim of this study was to develop a reliable technique to test the AMS function by using an external electronic device capable of mimicking the occurrence of supraventricular arrhythmias (Supraventricular Arrhythmia Simulator [SAS]). The SAS delivers low voltage pulse trains (200 mV, 20 ms) through two skin electrodes. Each pulse train lasts 15 seconds and starts synchronously with a pacing pulse of the implanted pacemaker to avoid interference from the operator. The pulse train rate is set at 350, 250, and 160 beats/min to simulate AF, atrial flutter, and atrial tachycardia (AT), respectively. Thirty-five patients implanted with Vitatron pacemakers, whose AMS system has been previously validated, were enrolled. Atrial and ventricular sensing were programmed in unipolar mode at 0.5 mV and in bipolar mode at > 2 mV, respectively. All pulses from the SAS were detected by the atrial channel at an amplitude ranging from 1 to 3 mV. The test proved to be safe and reliable at rest and during exercise. AMS occurred immediately at onset or at offset of atrial arrhythmias, and no adverse interference on pacemaker function was seen from the SAS. In conclusion, the described technique and the SAS are safe and reliable for patient and pacemaker function and can be proposed as a useful method to verify proper performance of AMS function irrespective of the type of implanted devices.

  11. Study on the neotype zirconia's implant coated nanometer hydroxyapatite ceramics

    Science.gov (United States)

    Zhu, J. W.; Yang, D. W.

    2007-07-01

    In recent years, biologic ceramics is a popular material of implants and bioactive surface modification of dental implant became a research emphasis, which aims to improve bioactivity of implants materials and acquire firmer implants-bone interface. The zirconia ceramic has excellent mechanical properties and nanometer HA ceramics is a bioceramic well known for its bioactivity, therefore, nanometer HA ceramics coating on zirconia, allows combining the excellent mechanical properties of zirconia substrates with its bioactivity. This paper shows a new method for implant shape design and bioactive modification of dental implants surface. Zirconia's implant substrate was prepared by sintered method, central and lateral tunnels were drilled in the zirconia hollow porous cylindrical implants by laser processing. The HA powders and needle-like HA crystals were made by a wet precipitation and calcining method. Its surface was coated with nanometer HA ceramics which was used brush HA slurry and vacuum sintering. Mechanical testing results revealed that the attachment strength of nanometer HA ceramics coated zirconia samples is high. SEM and interface observation after inserted experiment indicated that calcium and phosphor content increased and symmetrically around coated implant-bone tissue interface. A significantly higher affinity index was demonstrated in vivo by histomorphometric evaluation in coated versus uncoated implants. SEM analysis demonstrated better bone adhesion to the material in coated implant at any situation. In addition, the hollow porous cylindrical implant coated with nanometer HA ceramics increase the interaction of bone and implant, the new bone induced into the surface of hollow porous cylindrical implant and through the most tunnels filled into central hole. The branch-like structure makes the implant and bone a body, which increased the contact area and decreased elastic ratio. Therefore, the macroscopical and microcosmic nested structure of

  12. Bone healing at implants with a fluoride-modified surface: an experimental study in dogs.

    Science.gov (United States)

    Berglundh, T; Abrahamsson, I; Albouy, J-P; Lindhe, J

    2007-04-01

    The aim of the present experiment was to study early stages of osseointegration to implants with a fluoride-modified surface. Six mongrel dogs, about 1-year old, were used. All mandibular premolars and the first mandibular molars were extracted. Three months later, mucoperiosteal flaps were elevated in one side of the mandible and six sites were identified for implant placement. The control implants (MicroThread) had a TiOblast surface, while the test implants (OsseoSpeed) had a fluoride-modified TiOblast surface. Both types of implants had a similar geometry, a diameter of 3.5 mm and were 8 mm long. Following installation, cover screws were placed and the flaps were adjusted and sutured to cover all implants. Four weeks after the first implant surgery, the installation procedure was repeated in the opposite side of the mandible. Two weeks later, biopsies were obtained and prepared for histological analysis. The void that occurred between the cut bone wall of the recipient site and the macro-threads of the implant immediately following implant installation was used to study early bone formation. It was demonstrated that the amount of new bone that formed in the voids within the first 2 weeks of healing was larger at fluoride-modified implants (test) than at TiOblast (control) implants. It was further observed that the amount of bone-to-implant contact that had been established after 2 weeks in the macro-threaded portion of the implant was significantly larger at the test implants than at the controls. It is suggested that the fluoride-modified implant surface promotes osseointegration in the early phase of healing following implant installation.

  13. Time course of fibronectin in the peri-implant tissue and neointima formation after functional implantation of polyester-based vascular prostheses with different porosity in pigs.

    Science.gov (United States)

    Patrzyk, Maciej; Hoene, Andreas; Jarchow, Raymond; Wilhelm, Lutz; Walschus, Uwe; Zippel, Roland; Schlosser, Michael

    2010-10-01

    Intima hyperplasia, resulting from extracellular matrix (ECM) secretion, can lead to vascular prosthesis occlusion and is a major problem in vascular surgery. Fibronectin might contribute to ongoing ECM secretion. However, the exact role of fibronectin and its influence on neointima formation remains unclear. This study was aimed at investigating the time course of the fibronectin area fraction and neointima formation following the functional implantation of three different polyester vascular prostheses into pigs. The infrarenal aorta from 15 animals (n = 5/group) was replaced by prosthesis segments with low, medium and high primary porosity. After 7, 14, 21, 28 and 116 days, the prostheses were morphometrically examined. Overall, the fibronectin area fraction was inversely correlated with the neointima thickness, demonstrating high fibronectin levels in the early phase (days 7 and 14) and low levels in the later phase with almost complete neointima formation (days 21-116). Throughout the study, fibronectin levels were highest at the proximal anastomosis region. The low porosity prosthesis had the highest fibronectin area fraction and a delayed neointima formation in the middle phase (days 21 and 28) but the highest neointima lining on day 116. The results indicate a relationship between fibronectin and neointima formation with the prosthesis porosity, demonstrating the importance of the textile design for tissue reactions following implantation.

  14. Time course of fibronectin in the peri-implant tissue and neointima formation after functional implantation of polyester-based vascular prostheses with different porosity in pigs

    Energy Technology Data Exchange (ETDEWEB)

    Patrzyk, Maciej; Hoene, Andreas [Department of Surgery, Ernst Moritz Arndt University Greifswald, Friedrich-Loeffler-Str. 23, D-17489 Greifswald (Germany); Jarchow, Raymond [Computation Centre, Ernst Moritz Arndt University Greifswald, Felix-Hausdorff-Str. 12, D-17489 Greifswald (Germany); Wilhelm, Lutz [Department of Surgery, Hospital Demmin, Loitzer Str. 1, D-17109 Demmin (Germany); Walschus, Uwe; Schlosser, Michael [Research Group of Predictive Diagnostics of the Department of Medical Biochemistry and Molecular Biology and Institute of Pathophysiology, Ernst Moritz Arndt University Greifswald, Greifswalder Str. 11c, D-17495 Karlsburg (Germany); Zippel, Roland, E-mail: schlosse@uni-greifswald.d [Department of Surgery, Elbland Hospital Center, Weinbergstr. 8, D-01589 Riesa (Germany)

    2010-10-01

    Intima hyperplasia, resulting from extracellular matrix (ECM) secretion, can lead to vascular prosthesis occlusion and is a major problem in vascular surgery. Fibronectin might contribute to ongoing ECM secretion. However, the exact role of fibronectin and its influence on neointima formation remains unclear. This study was aimed at investigating the time course of the fibronectin area fraction and neointima formation following the functional implantation of three different polyester vascular prostheses into pigs. The infrarenal aorta from 15 animals (n = 5/group) was replaced by prosthesis segments with low, medium and high primary porosity. After 7, 14, 21, 28 and 116 days, the prostheses were morphometrically examined. Overall, the fibronectin area fraction was inversely correlated with the neointima thickness, demonstrating high fibronectin levels in the early phase (days 7 and 14) and low levels in the later phase with almost complete neointima formation (days 21-116). Throughout the study, fibronectin levels were highest at the proximal anastomosis region. The low porosity prosthesis had the highest fibronectin area fraction and a delayed neointima formation in the middle phase (days 21 and 28) but the highest neointima lining on day 116. The results indicate a relationship between fibronectin and neointima formation with the prosthesis porosity, demonstrating the importance of the textile design for tissue reactions following implantation.

  15. An accuracy study of computer-planned implant placement in the augmented maxilla using osteosynthesis screws.

    Science.gov (United States)

    Verhamme, L M; Meijer, G J; Soehardi, A; Bergé, S J; Xi, T; Maal, T J J

    2017-04-01

    Previous research on the accuracy of flapless implant placement of virtually planned implants in the augmented maxilla revealed unfavourable discrepancies between implant planning and placement. By using the osteosynthesis screws placed during the augmentation procedure, the surgical template could be optimally stabilized. The purpose of this study was to validate this method by evaluating its clinically relevant accuracy. Twelve consecutive fully edentulous patients with extreme resorption of the maxilla were treated with a bone augmentation procedure. Virtual implant planning was performed and a surgical template was manufactured. Subsequently, six implants were installed using the surgical template, which was only supported by the osteosynthesis screws. Implant deviations between planning and placement were calculated. A total of 72 implants were installed. Mean deviations found in the mesiodistal direction were 0.817mm at the implant tip and 0.528mm at the implant shoulder. The angular deviation was 2.924°. In the buccolingual direction, a deviation of 1.038mm was registered at the implant tip and 0.633mm at the implant shoulder. The angular deviation was 3.440°. This study showed that implant placement in the augmented maxilla using a surgical template supported by osteosynthesis screws is accurate.

  16. Effect of tilted and short distal implants on axial forces and bending moments in implants supporting fixed dental prostheses: an in vitro study.

    Science.gov (United States)

    Ogawa, Toru; Dhaliwal, Sandra; Naert, Ignance; Mine, Atsushi; Kronstrom, Mats; Sasaki, Keiichi; Duyck, Joke

    2010-01-01

    The aim of this study was to evaluate the axial forces (AFs) and bending moments (BMs) on implants supporting a fixed dental prosthesis (FDP) with a distal cantilever (10 mm) compared to an FDP supported by a tilted or short (7 mm instead of 13 mm) posterior implant by means of in vitro strain gauge measurements. Nine titanium Branemark implants were placed in an edentulous composite mandible. The mechanical loading conditions were evaluated for the following three situations: (1) short distal implants supporting a cantilever, (2) long tilted distal implants, and (3) no distal implants supporting a cantilever. A vertical load of 50 N was applied at the first molar position, and the resultant AFs and BMs were measured for the three different situations, three different numbers of supporting implants (three, four, or five), and three different prosthesis materials (titanium, acrylic, and fiber-reinforced acrylic). The mean BMs, as well as the maximum AFs and BMs, were significantly higher in the model with a cantilever compared to that having the tilted or short distal implants (P models with a distally tilted implant versus a short distal implant. The use of posterior implants reduced the AFs and BMs on implants supporting an FDP compared to that with a distal cantilever. No difference in mechanical loading was observed between short tilted distal implants.

  17. Electrophysiological testing of visual function after mirror telescope implantation: a case report.

    Science.gov (United States)

    Kremláček, Jan; Jirásková, Naďa; Nekolová, Jana; Šikl, Radovan; Kuba, Miroslav

    2016-12-01

    The implantation of an intraocular telescope increases life quality in patients with end-stage age-related macular degeneration (AMD). The present study monitored changes in electrophysiological markers of visual processing before and during seventeen months after a novel mirror telescope implantation in two patients (OV-male 90 years, MZ-female 70 years) with the final-stage form of AMD. Visual evoked potentials were recorded to high-contrast pattern-reversal (PR-VEP for check size 40' and 10'), low-contrast motion-onset stimuli (in visual periphery M-VEP M20°, and in central part M-VEP C8°), and event-related potentials (ERPs) in the oddball visual paradigm. MZ's more systematic responses showed attenuation and prolongation of the M-VEP M20° and the PR-VEP 40' immediately after the telescope implantation with a slow amplitude recovery with unchanged prolonged latency. The implantation completely eradicated the M-VEP C8° without any restoration. The PR-VEP 10' were not readable. Only a part of OV's PR-VEP 40' and M-VEP M20' were of a repeatable and expected morphology. These OV's VEPs were consistent with MZ's findings. The ERPs did not show any effect of implantation in both patients. Post-implantation visual acuity and reaction time overcame the pre-implantation levels. The mirror telescope preserved peripheral vision in contrast to classic telescopes; however, the telescope concurrently reduced the luminance of the magnified retinal image, which was likely responsible for the prolongation of the VEP latencies.

  18. Nanomechanical properties of bone around cement-retained abutment implants. A minipig study

    Directory of Open Access Journals (Sweden)

    R.R.M. de Barros

    2016-06-01

    Full Text Available Aim The nanomechanical evaluation can provide additional information about the dental implants osseointegration process. The aim of this study was to quantify elastic modulus and hardness of bone around cemented-retained abutment implants positioned at two different crestal bone levels. Materials and methods The mandibular premolars of 7 minipigs were extracted. After 8 weeks, 8 implants were inserted in each animal: crestally on one side of the mandible and subcrestally on the other (crestal and subcrestal groups. Functional loading were immediately provided with abutments cementation and prostheses installation. Eight weeks later, the animals euthanasia was performed and nanoindentation analyses were made at the most coronal newly formed bone region (coronal group, and below in the threaded region (threaded group of histologic sections. Results The comparisons between subcrestal and crestal groups did not achieve statistical relevance; however the elastic modulus and hardness levels were statistically different in the two regions of evaluation (coronal and threaded. Conclusions The crestal and subcrestal placement of cement-retained abutment implants did not affect differently the nanomechanical properties of the surrounding bone. However the different regions of newly formed bone (coronal and threaded groups were extremely different in both elastic modulus and hardness, probably reflecting their differences in bone composition and structure.

  19. Exploratory study of perceived quality of life with implanted standing neuroprostheses

    Directory of Open Access Journals (Sweden)

    Loretta M. Rohde, PT, DPT

    2012-04-01

    Full Text Available Individuals with spinal cord injury (SCI need options for negotiating architectural barriers, completing essential transfers, and accessing items on high shelves or in cupboards that cannot be reached from the wheelchair or safely managed with reachers. Case Western Reserve University (CWRU and the Department of Veterans Affairs (VA have developed an assistive technology device to assist individuals with SCI to stand and transfer. The 8-channel implanted CWRU-VA system enables persons with SCI to exercise, stand, and maneuver in the vicinity of their wheelchairs. Interventions that decrease barriers to mobility and participation can have a significant effect on an individual’s perceived quality of life (QOL. This study uses a qualitative research methodology comprised of a series of semi-structured interviews to determine the effects on perceived QOL of an implanted 8-channel functional electrical stimulation (FES system for standing after SCI. The results reveal that individuals with SCI currently using an implanted FES standing system perceived significant improvements in QOL related to the neuroprosthesis. Implanted neuroprostheses for standing have the potential to improve QOL for veterans living with SCI.

  20. Exploratory study of perceived quality of life with implanted standing neuroprostheses.

    Science.gov (United States)

    Rohde, Loretta M; Bonder, Bette R; Triolo, Ronald J

    2012-01-01

    Individuals with spinal cord injury (SCI) need options for negotiating architectural barriers, completing essential transfers, and accessing items on high shelves or in cupboards that cannot be reached from the wheelchair or safely managed with reachers. Case Western Reserve University (CWRU) and the Department of Veterans Affairs (VA) have developed an assistive technology device to assist individuals with SCI to stand and transfer. The 8-channel implanted CWRU-VA system enables persons with SCI to exercise, stand, and maneuver in the vicinity of their wheelchairs. Interventions that decrease barriers to mobility and participation can have a significant effect on an individual's perceived quality of life (QOL). This study uses a qualitative research methodology comprised of a series of semi-structured interviews to determine the effects on perceived QOL of an implanted 8-channel functional electrical stimulation (FES) system for standing after SCI. The results reveal that individuals with SCI currently using an implanted FES standing system perceived significant improvements in QOL related to the neuroprosthesis. Implanted neuroprostheses for standing have the potential to improve QOL for veterans living with SCI.

  1. A new classification of peri-implant bone morphology: a radiographic study of patients with lower implant-supported mandibular overdentures

    NARCIS (Netherlands)

    L. Zhang; W. Geraets; Y. Zhou; W. Wu; D. Wismeijer

    2014-01-01

    Objective This study aimed to classify peri-implant bone defects (PIBDs) on the basis of their radiographic appearance in a cohort of patients with lower implant-supported overdentures. Materials and methods Eighty-three patients with lower implant-supported overdentures were recruited to participat

  2. Cochlear implant benefits in deafness rehabilitation: PET study of temporal voice Activations

    Energy Technology Data Exchange (ETDEWEB)

    Coez, A.; Zilbovicius, M. [CEA, Serv Hosp Frederic Joliot, INSERM, Res Unit Neuroimaging and Psychiat, U797, IFR49, F-91406 Orsay (France); Zilbovicius, M.; Syrota, A.; Samson, Y. [CEA, DSV, DRM, Serv Hosp Frederic Joliot, F-91406 Orsay (France); Bizaguet, E. [Lab Correct Audit, Paris (France); Coez, A. [Univ Paris Sud 11, Paris (France); Ferrary, E.; Bouccara, D.; Mosnier, I.; Sterkers, O. [INSERM, Unit M 867, Paris (France); Ambert-Dahan, E. [Hop Beaujon, Serv ORL Chirurg Cervicofaciale, AP-HP, Clichy (France); Ferrary, E.; Bouccara, D.; Mosnier, I.; Sterkers, O. [Inst Fed Rech Claude Bernard Physiol et Pathol, IFR02, Paris (France); Samson, Y. [Hop La Pitie Salpetriere, Serv Urgences Cerebro-vasc, AP-HP, Paris (France); Samson, Y. [Univ Paris 06, Paris (France); Sterkers, O. [Univ Denis Diderot Paris 7, Paris (France)

    2008-07-01

    Cochlear implants may improve the medical and social prognosis of profound deafness. Nevertheless, some patients have experienced poor results without any clear explanations. One correlate may be an alteration in cortical voice processing. To test this hypothesis, we studied the activation of human temporal voice areas (TVA) using a well-standardized PET paradigm adapted from previous functional MRI (fMRI) studies. Methods: A PET H{sub 2}{sup 15}O activation study was performed on 3 groups of adult volunteers: normal-hearing control subjects (n 6) and cochlear-implanted post-lingually deaf patients with {>=}2 y of cochlear implant experience, with intelligibility scores in the 'Lafon monosyllabic task' {>=}80% (Good group; n 6) or {<=}20% (Poor group; n 6). Relative cerebral blood flow was measured in 3 conditions: rest, passive listening to human voice, and non-voice stimuli. Results: Compared with silence, the activations induced by non-voice stimuli were bilaterally located in the superior temporal regions in all groups. However these activations were significantly and similarly reduced in both cochlear implant groups, whereas control subjects showed supplementary activations. Compared with non-voice, the voice stimuli induced bilateral activation of the TVA along the superior temporal sulcus (STS) in both the control and the Good groups. In contrast, these activations were not detected in the Poor group, which showed only left unilateral middle STS activation. Conclusion: These results suggest that PET is an adequate method to explore cochlear implant benefits and that this benefit could be linked to the activation of the TVA. (authors)

  3. [PRIMARY STUDY ON IMPLANT COVERAGE WITH LOCAL SOFT TISSUE IN IMMEDIATE IMPLANT-BASED BREAST RECONSTRUCTION].

    Science.gov (United States)

    Li, Guangxue; Mu, Lan; Liu, Yan; Yang, Kai; Peng, Zhe; Bi, Ye

    2016-03-01

    To explore the method of implant coverage with local soft tissue in immediate implant-based breast reconstruction and to evaluate the early effectiveness. Between April 2014 and August 2015, 11 patients with breast cancer underwent immediate breast reconstruction with implants after mastectomy, and the clinical data were reviewed retrospectively. The age ranged 29-48 years (mean, 36 years). The disease duration was from 7 days to 12 months (median, 3 months). According to tumor staging, 3 cases were rated as T(is)N0M0, 4 cases as T1N0M0, and 4 cases as T2N0M0. The implants were covered with local soft tissue according to the volume of mastectomy and contralateral breast size, including pectoralis major myocutaneous flaps with inframammary adipofasical flaps (3 cases), with serratus anterior fascial flap (5 cases), with rectus sheath fascial flap (1 case), and with serratus anterior fascial flap and rectus sheath fascial flap (2 cases). The size of pectoralis major myocutaneous flaps ranged from 15 cm x 9 cm to 20 cm x 15 cm, and the serratus anterior fascial flaps from 10 cm x 8 cm to 15 cm x 10 cm, and the rectus sheath fascial flap from 8 cm x 6 cm to 10 cm x 8 cm. One patient had partial nipple necrosis postoperatively and was cured, and no other postoperative complications of hematoma, infection, or implant exposure was found. The patients were followed up 4-13 months (median, 8 months). The reconstructive outcomes were excellent in 10 cases and good in 1 case, with an excellent and good rate of 100%. During follow-up, no rupture or exposure of the implant was observed; capsular contracture (Baker grade II) occurred in 1 case. Adequate coverage of implants with different local soft tissue flaps can achieve satisfactory early effectiveness in immediate implant-based breast reconstruction after mastectomy.

  4. Experimental study on penetration of dental implants into the maxillary sinus in different depths

    Directory of Open Access Journals (Sweden)

    Weijian ZHONG

    2013-12-01

    Full Text Available The exposing of dental implant into the maxillary sinus combined with membrane perforation might increase risks of implant failure and sinus complications. Objective: The purpose of this study was to investigate the effects of the dental implant penetration into the maxillary sinus cavity in different depths on osseointegration and sinus health in a dog model. Material and Methods: Sixteen titanium implants were placed in the bilateral maxillary molar areas of eight adult mongrel dogs, which were randomly divided into four groups according to the different penetrating extents of implants into the sinus cavities (group A: 0 mm; group B: 1 mm; group C: 2 mm; group D: 3 mm. The block biopsies were harvested five months after surgery and evaluated by radiographic observation and histological analysis. Results: No signs of inflammatory reactions were observed in any maxillary sinus of the eight dogs. The tips of the implants with penetrating depth of 1 mm and 2 mm were found to be fully covered with newly formed membrane and partially with new bone. The tips of the implants with penetrating depth over 3 mm were exposed in the sinus cavity and showed no membrane or bone coverage. No significant differences were found among groups regarding implant stability, bone-to-implant contact (BIC and bone area in the implant threads (BA. Conclusions: Despite the protrusion extents, penetration of dental implant into the maxillary sinus with membrane perforation does not compromise the sinus health and the implant osseointegration in canine.

  5. Clinical study of customized aspherical intraocular lens implants

    Institute of Scientific and Technical Information of China (English)

    Lie-Xi; Jia; Zhao-Hui; Li

    2014-01-01

    AIM:To compare if there is an improvement in visual functions with age-related cataracts between patients receiving a aspherical intraocular lens(IOL) based on corneal wavefront aberration and patients randomly assigned lenses.METHODS:A total of 124 eyes of 124 patients with age-related cataracts were placed in experimental group and a group receiving randomly assigned(RA) lenses.The experimental group was undergone Pentacam corneal spherical aberration measurement before surgery; the targeted range for residual total spherical aberration after surgery was set to 0-0.3 μm. Patients with a corneal spherical aberration <0.3 μm were implanted with a zero-spherical aberration advanced optics(AO) aspherical IOL and patients with an aberration ≥0.3 μm received a Tecnis Z9003 aspherical lens in experimental group. RA patients were randomly implanted with an AO lens or a Tecnis Z9003 lens. Three months after surgery total spherical aberration, photopic/mesopic contrast sensitivities, photopic/mesopic with glare contrast sensitivities, and logMAR vision were measured.RESULTS:Statistical analysis on logMAR vision showed no significant difference between two groups(P =0.413). The post-surgical total spherical aberration was 0.126 ±0.097 μm and 0.152 ±0.151 μm in the experimental and RA groups, respectively(P =0.12). The mesopic contrast sensitivities at spatial frequencies of 6,12 and 18 c/d in the experimental group were significantly higher than of the RA group(P =0.00; P =0.04;P =0.02). The mesopic with glare contrast sensitivity in the experimental group at a spatial frequency of 18 c/d was also significantly higher vs the RA group(P =0.01).CONCLUSION:Pre-surgical corneal spherical aberration measurement in cataract patients followed bycustomized selection of aspherical IOL implants improved mesopic contrast sensitivities at high spatial frequencies, and thus is a superior strategy compared to the random selection of aspherical intraocular lens implants.

  6. Effect of implant macro-design on primary stability: A prospective clinical study

    Science.gov (United States)

    Lozano-Carrascal, Naroa; Salomó-Coll, Oscar; Gilabert-Cerdà, Marta; Farré-Pagés, Nuria; Hernández-Alfaro, Federico

    2016-01-01

    Background Implant restorations have become a high predictable treatment option. Several caracteristics such as surgical technique and implant design can influence the treatment outcomes. The aim of the present study was to evaluate the influence of implant macro-design on primary stability measured with resonance frequency analysis (RFA) and insertion torque (IT). Material and Methods A total of 47 implants divided in two groups: Test group (TI): 22 Tapered MIS® Seven implants; Control group (CI): 25 cylindrical Astra® Osseospeed implants. All implants were inserted following the manufacturers’ standard protocols. Implant primary stability was measured at the moment of implant placement by registering insertion torque values (ITv) and ISQ values by means of Osstell™ Mentor (ISQv) (Integration Diagnostic Ltd., Goteborg, Sweden). Results In the mandible, mean ISQv for tapered implants (TI) was 71.67±5.16 and for cylindrical implants (CI) 57.15±4.83 (p=0.01). Mean insertion torque was 46.67±6.85 Ncm for TI and 35.77±6.72 Ncm for CI (p=0.01). In the maxilla, mean ISQ was 67.2±4.42 for tapered implants and 49.17±15.30 for cylindrical implants (p=0.01). Mean insertion torque for TI was 41.5±6.26 Ncm and for CI 39.17±6.34 Ncm (p>0.05). For tapered implants, no correlation could be found between implant diameter and primary stability. But for cylindrical implants there was a statistically significant correlation between implant diameter and primary stability: ITv (p=0.03); ISQv (p=0.04). Conclusions Within the limits of the present study, tapered shaped implants achieve higher primary stability measured through ISQ and insertion torque values. Moreover, for cylindrical implants positive correlation has been established between implant diameter and primary stability. Key words:Primary stability, tapered, cylindrical, conical, implant macro-design. PMID:26827067

  7. Accelerated Recovery of Endothelium Function after Stent Implantation with the Use of a Novel Systemic Nanoparticle Curcumin

    Directory of Open Access Journals (Sweden)

    Qi Lu

    2015-01-01

    Full Text Available Curcumin was reported to exhibit a wide range of pharmacological effects including antioxidant, anti-inflammatory, and antiproliferative activities and significantly prevent smooth muscle cells migration. In the present study, a novel kind of curcumin loaded nanoparticles (Cur-NP has been prepared and characterized with the aim of inhibiting inflammation formation and accelerating the healing process of the stented arteries. Cur-NP was administrated intravenously after stent implantation twice a week and detailed tissue responses were evaluated. The results demonstrated that intravenous administration of Cur-NP after stent implantation accelerated endothelial cells restoration and endothelium function recovery and may potentially be an effective therapeutic alternative to reduce adverse events for currently available drug eluting stents.

  8. The benefit of the reverse transfer function in the fitting process of the Vibrant Soundbridge middle ear implant.

    Science.gov (United States)

    Karkas, Alexandre; Chahine, Karim; Schmerber, Sébastien

    2012-02-01

    Reverse transfer function (RTF) measurement of the Vibrant Soundbridge (VSB) middle ear implant (MEI) is an objective method to evaluate the function of the VSB and can be used to adjust the Connexx value required to reach the optimal VSB gain during fitting sessions. To investigate the sound transfer of the VSB with the RTF in implanted patients and evaluate the role of RTF in the fitting process of the VSB. This was a prospective study including patients undergoing VSB implantation and RTF recording from March 2007 to October 2010. Three parameters were analyzed. 1) RTF: energy transmitted in dB SPL to ear canal by retrograde vibration of malleus and tympanic membrane. 2) Connexx value: level of amplification in dB delivered by the audioprocessor to the floating mass transducer (FMT). 3) VSB gain: difference in dB HL in free field between aided and unaided conditions. Ten patients fitted the criteria. RTF measurements revealed a significant inter-patient disparity. We adjusted the Connexx value according to the RTF value to obtain an optimal VSB gain within comfort levels. The VSB gain and RTF with Connexx value were closely correlated together. The mean VSB gain and RTF value converted to dB HL had comparable values.

  9. Occlusion on oral implants: current clinical guidelines.

    Science.gov (United States)

    Koyano, K; Esaki, D

    2015-02-01

    Proper implant occlusion is essential for adequate oral function and the prevention of adverse consequences, such as implant overloading. Dental implants are thought to be more prone to occlusal overloading than natural teeth because of the loss of the periodontal ligament, which provides shock absorption and periodontal mechanoreceptors, which provide tactile sensitivity and proprioceptive motion feedback. Although many guidelines and theories on implant occlusion have been proposed, few have provided strong supportive evidence. Thus, we performed a narrative literature review to ascertain the influence of implant occlusion on the occurrence of complications of implant treatment and discuss the clinical considerations focused on the overloading factors at present. The search terms were 'dental implant', 'dental implantation', 'dental occlusion' and 'dental prosthesis'. The inclusion criteria were literature published in English up to September 2013. Randomised controlled trials (RCTs), prospective cohort studies and case-control studies with at least 20 cases and 12 months follow-up interval were included. Based on the selected literature, this review explores factors related to the implant prosthesis (cantilever, crown/implant ratio, premature contact, occlusal scheme, implant-abutment connection, splinting implants and tooth-implant connection) and other considerations, such as the number, diameter, length and angulation of implants. Over 700 abstracts were reviewed, from which more than 30 manuscripts were included. We found insufficient evidence to establish firm clinical guidelines for implant occlusion. To discuss the ideal occlusion for implants, further well-designed RCTs are required in the future.

  10. Observational study of 67 wide platform implants treated with avantblast surface. Results at three year.

    Science.gov (United States)

    Barona-Dorado, Cristina; Martínez-Rodríguez, Natalia; Torres-Lear, Francisco; Martínez-González, José-Ma

    2009-04-01

    This paper shows the results of the clinical and radiographic behavior, at 3 years, of 67 wide platform implants undergoing prosthetic load. This is an observational prospective study of 67 implants in 49 patients within the range of 54-69 years of age. Screening was performed after a radiological study with panoramic and tomographic radiographs followed by the implantological treatment with prosthetic load and clinical (15 days, 1, 6, 12, 24 and 36 months) and radiological control follow-up (6, 12, 24 and 36 months). During the healing period 1 implant failed, representing a 98.5% survival. After placing the prosthesis, it was not necessary to remove any implant, therefore 66 implants remain successfully in place. The favorable results and follow-up after the prosthetic load of 66 implants (CSR of 100%) attest that wide platform implants can and should be applied after careful planning and case selection.

  11. Effects of new implant-retained overdentures on masticatory function, satisfaction and quality of life.

    Science.gov (United States)

    Mendes, Francielle A; Borges, Tânia de F; Gonçalves, Luiz C; de Oliveira, Terezinha Rc; do Prado, Célio J; das Neves, Flávio D

    2016-09-01

    The aim of this study is to evaluate the effects of replacing poorly fitting dentures on patient's masticatory function, satisfaction and oral health-related quality of life. Fourteen patients with conventional maxillary complete dentures and mandibular overdentures retained by two implants bar clip system had their dentures replaced. The laboratory tests for the analysis of masticatory performance were conducted using an "Optocal" food simulator test. Questionnaires were used to evaluate patient satisfaction with dentures and impact of oral health on quality of life. Tests were conducted and questionnaires were administered before and 1, 3 and 6 months after the patient had adapted to the new dentures. Masticatory performance data and satisfaction with dentures (Visual Analogic Scale) were statistically analyzed by ANOVA and Tukey b test, satisfaction with dentures (SATs P) and impact of oral health on quality of life were evaluated using the Wilcoxon and Friedman tests (a=.05). There was no statistically significant improvement in masticatory function after denture replacement, although better outcomes were observed. Satisfaction with dentures and total score obtained using the OHIPedent showed significant improvement. It can be suggested that the potential for grinding food, patient satisfaction and aspects of quality of life improved immediately after denture replacement.

  12. Clinical and biologic factors related to oral implant failure: a 2-year follow-up study.

    Science.gov (United States)

    Moheng, Patrick; Feryn, Jean-Marc

    2005-09-01

    The purpose of this study is to evaluate urinary biomarkers of bone formation and resorption as predictive factors for oral implant failure, and to contribute to the knowledge of factors related to oral implant failure. A total of 93 patients between 18 and 85 years old, with an indication of oral implant, were eligible in this 2-year prospective, open, and nonrandomized study. Patients who had bone graft before implantation or presented with prosthetic difficulties (implant-to-crown ratio coating. Serum osteocalcin, and urinary pyridinoline and deoxypyridinoline were measured, together with bone density at implant location. The primary endpoint (implant failure) was the implant removal (radiographic evidence of peri-implant bone loss and/or pockets). Factors related to implant failure were analyzed using multilevel logistic regression models to consider within-patient effects. Of the 93 patients included, 61% were female, and 16% were current smokers. A total of 266 oral implants were placed and analyzed, with a mean number of 3.1 implants by patient. Eleven and 15% of bone locations scored at D1 and D4, respectively, for the Misch bone density scoring. The majority of implants (72%) were placed more than 3 months after tooth extraction, using a Frialit-2 system in 73% of cases. The mean of osteocalcin was 17.3 (+/-9.4) ng/L; those of pyridinoline and deoxypyridinoline were 33.2 (+/-15.8) and 10.2 (+/-11.9) mmol per creatinine mmol, respectively. At one-year, 95.5% (95% confidence interval 92.5-97.5) of implants have not been removed. One year later, no further implant failed. In both univariate and multivariate analysis, osteocalcin, pyridinoline, and deoxypyridinoline were not significant predictive factors of oral implant failure. In multilevel logistic regression analysis, only tobacco consumption and single-tooth replacement or removable prosthesis were independent and significant predictive factors of oral implant failure. Serum osteocalcin, and urinary

  13. Executive functioning pattern as a prognostic indicator for shunt implantation surgery in patients with normal pressure hydrocephalus - A preliminary report.

    Science.gov (United States)

    Nowak, Marcin M; Fersten, Ewa; Głowacki, Mariusz

    2016-01-01

    The problem of executive functions in patients with normal pressure hydrocephalus (NPH) was investigated in the study. Executive function parameters were assumed to be among factors that may differentiate the clinical pattern in NPH. Two major indicators of executive functioning, i.e. flexibility and productivity of thinking, were assessed in neuropsychological examination using the Trail Making Test (TMT), Verbal Fluency Test (COWAT), and the Wisconsin Card Sorting Test (WCST). Participants in the study were 18 patients with NPH divided using a set of diagnostic criteria into two subgroups: with idiopathic active hydrocephalus (ACT) or with arrested hydrocephalus (ARR). Executive functioning patterns were found to differentiate between the two NPH subgroups. Namely, patients diagnosed with active hydrocephalus (who qualify for shunt implantation surgery) tended to present lower levels of verbal fluency in all semantic categories, which suggests a decreased productivity of thinking. Besides, ACT patients' performance on the WCST was significantly inferior on two measures: (1) they committed more non-perseverative errors (which indicates their chaotic way of working on the test and the occurrence of random responses) and (2) displayed lower ability of "learning to learn" (which suggests their impaired flexibility of thinking). These aspects of executive function, with productivity and flexibility of thinking first and foremost, seem promising as additional prognostic indicators to consider in patient selection for shunt implantation.

  14. Engineering the heart: Evaluation of conductive nanomaterials for improving implant integration and cardiac function

    Science.gov (United States)

    Zhou, Jin; Chen, Jun; Sun, Hongyu; Qiu, Xiaozhong; Mou, Yongchao; Liu, Zhiqiang; Zhao, Yuwei; Li, Xia; Han, Yao; Duan, Cuimi; Tang, Rongyu; Wang, Chunlan; Zhong, Wen; Liu, Jie; Luo, Ying; (Mengqiu) Xing, Malcolm; Wang, Changyong

    2014-01-01

    Recently, carbon nanotubes together with other types of conductive materials have been used to enhance the viability and function of cardiomyocytes in vitro. Here we demonstrated a paradigm to construct ECTs for cardiac repair using conductive nanomaterials. Single walled carbon nanotubes (SWNTs) were incorporated into gelatin hydrogel scaffolds to construct three-dimensional ECTs. We found that SWNTs could provide cellular microenvironment in vitro favorable for cardiac contraction and the expression of electrochemical associated proteins. Upon implantation into the infarct hearts in rats, ECTs structurally integrated with the host myocardium, with different types of cells observed to mutually invade into implants and host tissues. The functional measurements showed that SWNTs were essential to improve the performance of ECTs in inhibiting pathological deterioration of myocardium. This work suggested that conductive nanomaterials hold therapeutic potential in engineering cardiac tissues to repair myocardial infarction.

  15. Gold implant therapy of locomotory disorders in dogs - Case studies

    Directory of Open Access Journals (Sweden)

    Emilia Abrudean

    2016-06-01

    Full Text Available The case study was conducted between October and January 2015, on 7 dogs of different breeds and ages, which at clinical examination showed varying degrees of lameness. The dogs behavior and state of consciousness, their attitude in standing, decubitus and at walk and the presence of involuntary movements was assessed through inspection. Palpation was used to feel muscular tonus, local temperature and sensibility. Postural reactions were highlighted by carrying out forced positions of each limb, thus highlighting the proprioceptive sensitivity. By testing the spinal reflexes the reactions of the forelimbs and hind limbs were evaluated, seeking the state of normality, or the absence, diminution or exacerbation of these reflexes. Also, diagnostic imaging was performed consisting of simple radiographs, were performed for the cases that entered the clinic. In the case of digital X-rays, X-rays are passing through the subject being examined are filtered, then touch a plate of sensors able to convert signals generated into digital information with an image appear on the computer screen. Interpretation of results was done by assessing the degree of dysplasia, and the Norberg-Olson angle and stage. This study used digital radiography as imaging technique; the device was Rx-M EVO Fujifilm. On the basis of diagnostic imaging and computerized image, diagnosis was established for each case. The treatment protocol with gold implant was the same for all seven cases; the adopted procedure was the "Wiener" procedure, described by Kasper and Zohmann. The procedure began with establishing a set of points associated with the treatment of hip dysplasia, spondylosis, arthritis, and osteochondritis. For the therapeutic protocol to be performed correctly took the dogs were sedated. This was done with medetomidine hydrochloride (Dorbene vet, Pfizer, concentration 1 mg⁄ml, administered in a 0,1mg⁄kg body weight dose. The results were visible after a month from the

  16. A retrospective study on related factors affecting the survival rate of dental implants

    Science.gov (United States)

    Kang, Jeong-Kyung; Lee, Ki; Lee, Yong-Sang; Park, Pil-Kyoo

    2011-01-01

    PURPOSE The aim of this retrospective study is to analyze the relationship between local factors and survival rate of dental implant which had been installed and restored in Seoul Veterans Hospital dental center for past 10 years. And when the relationship is found out, it could be helpful to predict the prognosis of dental implants. MATERIALS AND METHODS A retrospective study of patients receiving root-shaped screw-type dental implants placed from January 2000 to December 2009 was conducted. 6385 implants were placed in 3755 patients. The following data were collected from the dental records and radiographs: patient's age, gender, implant type and surface, length, diameter, location of implant placement, bone quality, prosthesis type. The correlations between these data and survival rate were analyzed. Statistical analysis was performed with the use of Kaplan-Meier analysis, Chi-square test and odds ratio. RESULTS In all, 6385 implants were placed in 3755 patients (3120 male, 635 female; mean age 65 ± 10.58 years). 108 implants failed and the cumulative survival rate was 96.33%. There were significant differences in age, implant type and surface, length, location and prosthesis type (P.05). CONCLUSION Related factors such as age, implant type, length, location and prosthesis type had a significant effect on the implant survival. PMID:22259704

  17. Functional investigation of bone implant viability using radiotracers in a new model of osteonecrosis

    OpenAIRE

    Luis Schiper; Bluma Linkowski Faintuch; Roberto José da Silva Badaró; Erica Aparecida de Oliveira; Arana Chavez, Victor E.; Elisangela Chinen; Joel Faintuch

    2016-01-01

    OBJECTIVES: Conventional imaging methods are excellent for the morphological characterization of the consequences of osteonecrosis; however, only specialized techniques have been considered useful for obtaining functional information. To explore the affinity of radiotracers for severely devascularized bone, a new mouse model of isolated femur implanted in a subcutaneous abdominal pocket was devised. To maintain animal mobility and longevity, the femur was harvested from syngeneic donors. Two ...

  18. Design and experimental proof of selected functions in implantable artificial kidney

    OpenAIRE

    Ostadfar, Ali

    2013-01-01

    Renal failure results in poisoning because metabolic by-products are not promptly removed from the body. The main remedy for this condition is hemo-dialysis, where blood bypasses the kidneys and is filtered in a “dialyzer”, stationary machine. This research proposes and verifies novel techniques that allow an implantable device to replace a dialysis machine. This device would perform two important kidney functions: filtering solids and retaining desired electrolytes and small proteins. Three...

  19. Bone reactions adjacent to titanium implants subjected to static load. A study in the dog (I)

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2001-01-01

    The aim of the study was to evaluate the effect of lateral static load induced by an expansion force on the bone/implant interface and adjacent peri-implant bone. In 3 beagle dogs, the 2nd, 3rd and 4th mandibular premolars were extracted bilaterally. Twelve weeks later 8 implants of the ITI Dental...... Implant System were placed in each dog. Crowns connected in pairs were screwed on the implants 12 weeks after implant installation. The connected crowns contained an orthodontic expansion screw yielding 4 loading units in each dog. Clinical registrations, standardized radiographs and fluorochrome labeling...... were carried out during the 24-week loading period. Biopsies were harvested and processed for ground sectioning. The sections were subjected to histological examination. No evident marginal bone loss was observed at either test or control sites. The bone density and the mineralized bone-to-implant...

  20. Protocol for Bone Augmentation with Simultaneous Early Implant Placement: A Retrospective Multicenter Clinical Study

    Directory of Open Access Journals (Sweden)

    Peter Fairbairn

    2015-01-01

    Full Text Available Purpose. To present a novel protocol for alveolar bone regeneration in parallel to early implant placement. Methods. 497 patients in need of extraction and early implant placement with simultaneous bone augmentation were treated in a period of 10 years. In all patients the same specific method was followed and grafting was performed utilizing in situ hardening fully resorbable alloplastic grafting materials consisting of β-tricalcium phosphate and calcium sulfate. The protocol involved atraumatic extraction, implant placement after 4 weeks with simultaneous bone augmentation, and loading of the implant 12 weeks after placement and grafting. Follow-up periods ranged from 6 months to 10 years (mean of 4 years. Results. A total of 601 postextraction sites were rehabilitated in 497 patients utilizing the novel protocol. Three implants failed before loading and three implants failed one year after loading, leaving an overall survival rate of 99.0%. Conclusions. This standardized protocol allows successful long-term functional results regarding alveolar bone regeneration and implant rehabilitation. The concept of placing the implant 4 weeks after extraction, augmenting the bone around the implant utilizing fully resorbable, biomechanically stable, alloplastic materials, and loading the implant at 12 weeks seems to offer advantages when compared with traditional treatment modalities.

  1. Clinical Preliminary Study on Biodegradable Subcuta neous Contraceptive Implant-CaproF

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    CaproF is a biodegradable subcutaneous contraceptive implant of releasing lev onorgestrel (LNG), which is expected to provide an effective contraception for 2 years. This study was undertaken to assess the one-year preliminary clinical results of using CaproF in 19 subjects. All subjects (n = 19) completed the 1-year study, and the contraceptive effectiveness and follow up rate were both 100%. The incidence of side effects was low. The major side effects were menstrual disorder, but bleeding patterns tended to be improved and restored to be the same as pre-implantation ones with time. There were no significant increase in weight (P> 0. 05) and no changes in blood pres sure. In the 3d, 6th and 12th months after using CaproF, the cervical mucus became scanty and viscous without fern-like crystals. The amount of menstrual blood loss de creased from 49. 38 ml of pre-implantation to 33. 23 ml of the 12th month of using the implant (P<0.05). Hemoglobin concentrations showed no changes, but serum ferritin concentrations were slightly increased. No changes in liver function, kidney function, glucose tolerance test and lipoprotein levels were found. Determinations of sex hor mones (FSH, LH, E2 and progesterone) levels, ultrasonography of ovary, and en dometrial biopsy in observed group (n = 9) showed that all had normal ovulation before insertion. But ovulation was suppressed and endometrium development was inhibited after insertion. All basal body temperatures were single-phase patterns during the 1- year follow-up. This study suggested that CaproF is an effective, safe and acceptable long-acting contraceptive method. It is likely to reach its contraceptive effectiveness through suppressing ovulation, inhibiting endometrium development and influencing cervical musus characteristics.

  2. Clinical Preliminary Study on Biodegradable Subcuta-neous Contraceptive Implant-CaproF

    Institute of Scientific and Technical Information of China (English)

    刘春海; 钱丽娟

    2000-01-01

    CaproF is a biodegradable subcutaneous contraceptive implant of releasing lev-onorgestrel (LNG), which is expected to provide an effective contraception for 2 years. This study was undertaken to assess the one-year preliminary clinical results of using CaproF in 19 subjects. All subjects (n = 19) completed the 1-year study, and the contraceptive effectiveness and follow up rate were both 100%. The incidence of side effects was low. The major side effects were menstrual disorder, but bleeding patterns tended to be improved and restored to be the same as pre-implantation ones with time.There were no significant increase in weight (P> 0. 05) and no changes in blood pres-sure. In the 3rd, 6th and 12th months after using CaproF, the cervical mucus became scanty and viscous without fern-like crystals. The amount of menstrual blood loss de-creased from 49. 38 ml of pre-implantation to 33. 23 ml of the 12th month of using the implant (P< 0. 05). Hemoglobin concentrations showed no changes, but serum ferritin concentrations were slightly increased. No changes in liver function, kidney function,glucose tolerance test and lipoprotein levels zoere found. Determinations of sex hor-mones (FSH , LH , E2 and progesterone) levels, ultrasonography of ovary, and en-dometrial biopsy in observed group (n = 9) shorted that all had normal ovulation before insertion. But ovulation was suppressed and endometrium development was inhibited after insertion. All basal body temperatures were single-phase patterns during the 1-year follow-up. This study suggested that CaproF is an effective, safe and acceptable long-acting contraceptive method. It is likely to reach its contraceptive effectiveness through suppressing ovulation, inhibiting endometrium development and influencing cervical mucus characteristics.

  3. Decrease in work function of transparent conducting ZnO tin films by phosphorus ion implantation.

    Science.gov (United States)

    Heo, Gi-Seok; Hong, Sang-Jin; Park, Jong-Woon; Choi, Bum-Ho; Lee, Jong-Ho; Shin, Dong-Chan

    2008-09-01

    To confirm the possibility of engineering the work function of ZnO thin films, we have implanted phosphorus ions into ZnO thin films deposited by radio-frequency magnetron sputtering. The fabricated films show n-type characteristics. It is shown that the electrical and optical properties of those thin films vary depending sensitively on the ion dose and rapid thermal annealing time. Compared to as-deposited ZnO films, the work-function of phosphorus ion-implanted ZnO thin films is observed to be lower and decreases with increasing ion doses. It is likely that the zinc or oxygen vacancies are firstly filled with the implanted phosphorus ions. With further increased ions, free electrons are generated as Zn2+ sites are replaced by those ions or interstitial phosphorus ions increase at the lattice sites, the fermi level by which approaches the conduction band and thus the work function decreases. Those films exhibit the optical transmittance higher than 85% within the visible wavelength range (up to 800 nm).

  4. Implantation of cobalt in SnO2 thin films studied by TDPAC

    Directory of Open Access Journals (Sweden)

    Juliana Schell

    2017-05-01

    Full Text Available Here we report time differential perturbed angular correlation (TDPAC results of Co-doped SnO2 thin films. Making use of stable Co and radioactive 111In implanted at the Bonn Radioisotope Separator with energies of 80 keV and 160 keV, respectively, it was possible to study the dopant incorporation and its lattice location during annealing. The hyperfine parameters have been probed as a function of temperature in vacuum. Two quadrupole interactions were observed. At high temperatures the dominant fraction for the probe nuclei can be assigned to the Cd-incorporation at the cation substitutional site in a highly disordered structure, obtained after implantation, to high crystallinity for the measurements at 873 K and 923 K. The similarity in TDPAC spectra obtained in undoped SnO gives indirect evidence that In and Co diffuse to different depths during the annealing process. Other interpretations will be discussed.

  5. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies.

    Science.gov (United States)

    Navitha, Aerrolla; Jogala, Satheesh; Krishnamohan, Chinnala; Aukunuru, Jithan

    2014-04-01

    The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC) studies. Different implants (F1-F8) containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000) either alone or as their blends, and PLGA (75:25). The implants contained 40% of the drug. After fabrication, the implants were characterized for various in vitro properties such as drug release and physical strength. Prior to conducting drug release studies, optimum drug release method was developed based on IVIVC studies. An optimized formulation based on drug release and physical strength at the end of fabrication was selected from the various implants fabricated. The bioactivity, reversibility, and IVIVC of optimized formulation were determined using pharmacokinetic studies in rats. Short-term stability studies were conducted with optimized formulation. Drug release depended on polymer molecular weight. Implant fabricated using 50:50 polycaprolactone 45,000 and polycaprolactone 80,000 was considered optimized implant. Optimized formulation selected released the drug for 3-months in vitro and was physically rigid. The optimized implant was able to release the drug in vivo for a period of 3 months, the implants are reversible throughout the delivery interval and, a 100% IVIVC was achieved with optimized implant, suggesting the development of 3-month drug-releasing implant for risperidone. The optimized implant was stable for 6 months at room temperature (25°C) and 45°C. A novel implant for risperidone was successfully prepared and evaluated.

  6. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies

    Directory of Open Access Journals (Sweden)

    Aerrolla Navitha

    2014-01-01

    Full Text Available The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC studies. Different implants (F1-F8 containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000 either alone or as their blends, and PLGA (75:25. The implants contained 40% of the drug. After fabrication, the implants were characterized for various in vitro properties such as drug release and physical strength. Prior to conducting drug release studies, optimum drug release method was developed based on IVIVC studies. An optimized formulation based on drug release and physical strength at the end of fabrication was selected from the various implants fabricated. The bioactivity, reversibility, and IVIVC of optimized formulation were determined using pharmacokinetic studies in rats. Short-term stability studies were conducted with optimized formulation. Drug release depended on polymer molecular weight. Implant fabricated using 50:50 polycaprolactone 45,000 and polycaprolactone 80,000 was considered optimized implant. Optimized formulation selected released the drug for 3-months in vitro and was physically rigid. The optimized implant was able to release the drug in vivo for a period of 3 months, the implants are reversible throughout the delivery interval and, a 100% IVIVC was achieved with optimized implant, suggesting the development of 3-month drug-releasing implant for risperidone. The optimized implant was stable for 6 months at room temperature (25°C and 45°C. A novel implant for risperidone was successfully prepared and evaluated.

  7. Implant stability during initiation and resolution of experimental periimplantitis: an experimental study in the dog.

    Science.gov (United States)

    Sennerby, Lars; Persson, Leif G; Berglundh, Tord; Wennerberg, Ann; Lindhe, Jan

    2005-01-01

    Histologic studies have demonstrated the possibility to reestablish direct bone-implant contacts after ligature-induced periimplantitis. The influence of the reosseointegration on the stability of implants is not known. The aim of the present investigation was to study bone tissue and associated implant stability alterations that occurred during induction and resolution of periimplantitis using resonance frequency analysis (RFA), radiography, and histology. Three implants with smooth (turned) or roughened (SLA) surfaces were placed in each side of the edentulous mandible of four dogs. Experimental periimplantitis was induced for 3 months. Five weeks later, the animals were treated with antibiotics and surgical therapy and were followed for another 6 months. Periapical radiographs and RFA were used to evaluate marginal bone levels and implant stability throughout the study period. After termination, the tissue-implant interface was evaluated by light microscopy in ground sections. There was a linear relationship between radiographic and RFA findings because continuous loss of marginal bone and a decrease in implant stability were observed for both implant surfaces during the periimplantitis period. Antibiotic treatment and surgical therapy resulted in some reosseointegration, which was more marked for the SLA surface. The resonance frequency values corresponded well to the histometric measurements because reosseointegration resulted in an increase in implant stability. The findings from the present study indicate a linear relationship between marginal bone level and resonance frequency value. It is suggested that the RFA technique is sensitive and may be used to detect even a minor change in the level of bone-implant contact.

  8. Retrospective radiographic study of marginal bone changes of 88 implants placed with split crest technique in the maxillary latero-posterior area

    Directory of Open Access Journals (Sweden)

    S. Longoni

    2016-04-01

    Full Text Available Aim This article presents a retrospective study on the behavior of implants placed with split crest technique in lateroposterior maxillary class IV atrophy. Materials and Methods Subjects who underwent implant placement following split crest technique in the maxillary latero-posterior area were enrolled in the present retrospective study. After a mean period of 6.2 years of function implant survival and success rates were assessed. Moreover, radiographic examination was made on digital periapical radiographs and by means of a specific software. Bone level changes were measured as the difference between the peri-implants crestal bone level and the implants shoulder during the last patient’s visit recall examination. Results A total of 30 patients satisfied the inclusion criteria and were included in the study; the subjects were treated with 88 implants (64 transmucosal and 24 submerged. The observation period for all patients treated with split crest technique varied between 4 and 8 years (mean 6.2 years. The implants survival rate was 96.6% and the prostheses survival rate was 100%. Bone resorption ranged between 2.3 mm and 2.7 mm. Conclusion Implants inserted in conjunction with split crest technique seems to be a promising therapy with similar results as conventional implant surgery.

  9. Bacterial Colonization of the Implant-Abutment Interface (IAI) of Dental Implants with a Sloped Marginal Design: An in-vitro Study.

    Science.gov (United States)

    Koutouzis, Theofilos; Gadalla, Hana; Lundgren, Tord

    2016-02-01

    The aim of this study is to utilize an in vitro dynamic loading model to assess the potential risk of bacterial invasion into the Implant Abutment Interface (IAI) microgap of dental implants with sloped marginal design. Forty implants were divided into two groups (n = 20 per group) based on implant marginal design. Group 1 was comprised of implants with Morse-taper connection and conventional marginal design that connected to titanium abutments. Group 2 was comprised of implants with Morse-taper connection and sloped marginal design that connected to titanium abutments. The specimens were immersed in a bacterial solution of E. coli and loaded with 500,000 cycles of 160N using a chewing simulator. Following disconnection of fixtures and abutments, microbial samples were taken from the threaded portion of the abutment, plated and cultured under appropriate conditions. Ten out of twenty implants of Group 1 and eight out of twenty implants of Group 2 had IAI microgaps colonized by E. Coli. There was not a statistically significant difference in the mean number of E. Coli CFU detected between implants of Group 1 (mean 19.2, SD 23.6) and Group 2 (mean 12.5, SD18.9) (p > .05). The present study demonstrated that implants with a sloped marginal design exhibited similar risk for bacterial invasion into the IAI microgap under in vitro dynamic loading conditions compared to implants with conventional marginal design. © 2015 Wiley Periodicals, Inc.

  10. Positron annihilation Doppler broadening study of Xe-implanted aluminum

    Energy Technology Data Exchange (ETDEWEB)

    Yu, R.S., E-mail: yursh@ihep.ac.cn [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China); Maekawa, M.; Kawasuso, A. [Japan Atomic Energy Agency, Advanced Science Research Center, Watanuki 1233, Takasaki, Gunma 370-1292 (Japan); Wang, B.Y.; Wei, L. [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China)

    2013-10-01

    Positron annihilation Doppler broadening measurements were conducted to characterize information of defects in 380 keV Xe{sup +}-implanted aluminum upon thermal annealing at temperatures ranging from 100 to 600 °C. The results suggest a broad distribution in the depth of vacancy-type defects in all the as-implanted samples. Meanwhile, with an increase in implantation dose the defect-rich region shifts toward the sample surface. It was found that increasing the annealing temperature triggers surface-directed migration and coalescence of vacancy and Xe{sub n}V{sub m} clusters in samples with implantation doses of 1E15 and 1E16 Xe{sup +}cm{sup −2}. In the sample implanted with a high dose of 1E17 Xe{sup +}cm{sup −2}, positron annihilation revealed a decomposition and even elimination of such defects under post-implantation annealing treatment.

  11. SU-E-J-257: Image Artifacts Caused by Implanted Calypso Beacons in MRI Studies

    Energy Technology Data Exchange (ETDEWEB)

    Amro, H; Chetty, I; Gordon, J; Wen, N [Henry Ford Health System, Detroit, MI (United States)

    2014-06-01

    Purpose: The presence of Calypso Beacon-transponders in patients can cause artifacts during MRI imaging studies. This could be a problem for post-treatment follow up of cancer patients using MRI studies to evaluate metastasis and for functional imaging studies.This work assesses (1) the volume immediately surrounding the transponders that will not be visualized by the MRI due to the beacons, and (2) the dependence of the non-visualized volume on beacon orientation, and scanning techniques. Methods: Two phantoms were used in this study (1) water filled box, (2) and a 2300 cc block of pork meat. Calypso beacons were implanted in the phantoms both in parallel and perpendicular orientations with respect to the MR scanner magnetic field. MR image series of the phantom were obtained with on a 1.0T high field open MR-SIM with multiple pulse sequences, for example, T1-weighted fast field echo and T2-weighted turbo spin echo. Results: On average, a no-signal region with 2 cm radius and 3 cm length was measured. Image artifacts are more significant when beacons are placed parallel to scanner magnetic field; the no-signal area around the beacon was about 0.5 cm larger in orthogonal orientation. The no-signal region surrounding the beacons slightly varies in dimension for the different pulse sequences. Conclusion: The use of Calypso beacons can prohibit the use of MRI studies in post-treatment assessments, especially in the immediate region surrounding the implanted beacon. A characterization of the MR scanner by identifying the no-signal regions due to implanted beacons is essential. This may render the use of Calypso beacons useful for some cases and give the treating physician a chance to identify those patients prior to beacon implantation.

  12. Initial Stability Study of Calcium Phosphate Coated Dental Implants

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Thin film of biodegradable calcium phosphate coated on threaded commercially pure titanium( cp- Ti) dental implants has been investigated as one of alternatives to eliminate the problem of the long-term instability of plasma sprayed HA coated implants. In order to compare in-vivo hone-to-implant response behavior among as-machined, HA coated and CMP coated groups, each group was implanted into New Zealand white mature male rabbits for 2 and 6 weeks, and then in- vivo biological behavior was examined in terms of H&E staining. Initial stability and removable torques of implants were compared among three groups. Measured removable torque of CMP coated specimen at 6 wceks after implantation was significantly higher than that of non-coated group, but slightly lower than that of HA coated group, without any inflammatory response at the surrounding of the implants. The initial stability (ISQ value; implant stability quotient ) of CMP coated specimen at 2 weeks after implantation was slightly lower than that of HA coated group and significantly higher than that of non-coated group. However, after 6 weeks, ISQ value of CMP coated group was slightly higher than that of HA coated group and significantly higher than that of non-coated group.

  13. Next-generation biomedical implants using additive manufacturing of complex, cellular and functional mesh arrays.

    Science.gov (United States)

    Murr, L E; Gaytan, S M; Medina, F; Lopez, H; Martinez, E; Machado, B I; Hernandez, D H; Martinez, L; Lopez, M I; Wicker, R B; Bracke, J

    2010-04-28

    In this paper, we examine prospects for the manufacture of patient-specific biomedical implants replacing hard tissues (bone), particularly knee and hip stems and large bone (femoral) intramedullary rods, using additive manufacturing (AM) by electron beam melting (EBM). Of particular interest is the fabrication of complex functional (biocompatible) mesh arrays. Mesh elements or unit cells can be divided into different regions in order to use different cell designs in different areas of the component to produce various or continually varying (functionally graded) mesh densities. Numerous design elements have been used to fabricate prototypes by AM using EBM of Ti-6Al-4V powders, where the densities have been compared with the elastic (Young) moduli determined by resonant frequency and damping analysis. Density optimization at the bone-implant interface can allow for bone ingrowth and cementless implant components. Computerized tomography (CT) scans of metal (aluminium alloy) foam have also allowed for the building of Ti-6Al-4V foams by embedding the digital-layered scans in computer-aided design or software models for EBM. Variations in mesh complexity and especially strut (or truss) dimensions alter the cooling and solidification rate, which alters the alpha-phase (hexagonal close-packed) microstructure by creating mixtures of alpha/alpha' (martensite) observed by optical and electron metallography. Microindentation hardness measurements are characteristic of these microstructures and microstructure mixtures (alpha/alpha') and sizes.

  14. Implantation of the Medtronic Harmony Transcatheter Pulmonary Valve Improves Right Ventricular Size and Function in an Ovine Model of Postoperative Chronic Pulmonary Insufficiency.

    Science.gov (United States)

    Schoonbeek, Rosanne C; Takebayashi, Satoshi; Aoki, Chikashi; Shimaoka, Toru; Harris, Matthew A; Fu, Gregory L; Kim, Timothy S; Dori, Yoav; McGarvey, Jeremy; Litt, Harold; Bouma, Wobbe; Zsido, Gerald; Glatz, Andrew C; Rome, Jonathan J; Gorman, Robert C; Gorman, Joseph H; Gillespie, Matthew J

    2016-10-01

    Pulmonary insufficiency is the nexus of late morbidity and mortality after transannular patch repair of tetralogy of Fallot. This study aimed to establish the feasibility of implantation of the novel Medtronic Harmony transcatheter pulmonary valve (hTPV) and to assess its effect on pulmonary insufficiency and ventricular function in an ovine model of chronic postoperative pulmonary insufficiency. Thirteen sheep underwent baseline cardiac magnetic resonance imaging, surgical pulmonary valvectomy, and transannular patch repair. One month after transannular patch repair, the hTPV was implanted, followed by serial magnetic resonance imaging and computed tomography imaging at 1, 5, and 8 month(s). hTPV implantation was successful in 11 animals (85%). There were 2 procedural deaths related to ventricular fibrillation. Seven animals survived the entire follow-up protocol, 5 with functioning hTPV devices. Two animals had occlusion of hTPV with aneurysm of main pulmonary artery. A strong decline in pulmonary regurgitant fraction was observed after hTPV implantation (40.5% versus 8.3%; P=0.011). Right ventricular end diastolic volume increased by 49.4% after transannular patch repair (62.3-93.1 mL/m(2); P=0.028) but was reversed to baseline values after hTPV implantation (to 65.1 mL/m(2) at 8 months, P=0.045). Both right ventricular ejection fraction and left ventricular ejection fraction were preserved after hTPV implantation. hTPV implantation is feasible, significantly reduces pulmonary regurgitant fraction, facilitates right ventricular volume improvements, and preserves biventricular function in an ovine model of chronic pulmonary insufficiency. This percutaneous strategy could potentially offer an alternative for standard surgical pulmonary valve replacement in dilated right ventricular outflow tracts, permitting lower risk, nonsurgical pulmonary valve replacement in previously prohibitive anatomies. © 2016 American Heart Association, Inc.

  15. Dosimetric and functional analysis of 227 patients treated by permanents prostate implants; Analyse dosimetrique et fonctionnelle de 227 patients traites par implants prostatiques permanents

    Energy Technology Data Exchange (ETDEWEB)

    Champeaux-Orange, E.; Wachter, T. [CHR, 45 - Orleans (France); Le Floch, O.; Haillot, O.; Peneau, M.; Raynaud-Bougnoux, A. [CHU, 37 - Tours (France)

    2009-10-15

    The brachytherapy of prostate by permanent implants is included in the armamentarium of localized prostate cancers with external radiotherapy and radical prostatectomy. The quality evaluation of implantation is essential for the patient and the team managing him. Our retrospective work consisted in analysing the whole of dosimetry data and urinary, digestive and sexual functional results of patients treated in our centers. conclusion: the post-implantation dosimetry analysis is essential to improve the technique and to understand the evolutions. The method of scanning evaluation is difficult but is currently the most used by its accessibility. The low urinary, rectal and sexual morbidity of the brachytherapy makes of this treatment an attractive technique for the patients should be well selected. (N.C.)

  16. Development of novel risperidone implants using blends of polycaprolactones and in vitro in vivo correlation studies

    OpenAIRE

    2014-01-01

    The objective of this study was to develop a novel implant containing risperidone intended for long-term treatment in Schizophrenia utilizing in vitro in vivo correlation (IVIVC) studies. Different implants (F1-F8) containing an antipsychotic drug, risperidone, were prepared using a hot melt extrusion technique by taking polycaprolactones of different molecular weights (Mwt. 15000, 45000, 80000) either alone or as their blends, and PLGA (75:25). The implants contained 40% of the drug. After f...

  17. Survival of immediately versus delayed loaded short implants: a prospective case series study

    OpenAIRE

    Alvira González, Joaquín; Díaz Campos, Erick; Sánchez Garcés, María Angeles; Gay Escoda, Cosme

    2015-01-01

    Background To assess and compare survival rates of immediately and delayed loaded short implants (7 mm) in free ends of a partially edentulous jaw with moderate-severe alveolar bone resorption. Material and Methods 24 patients with atrophic edentulous free-ends were included in this prospective study. Four study groups were monitored monthly and their behavior was evaluated: bridges supported only by short implants and mixed short and long implant bridge groups, both with immediate and delaye...

  18. Acceleration of Medpor implant fibrovascularization with local vascular endothelial growth-factor injections: An experimental study

    Directory of Open Access Journals (Sweden)

    Mert Demirel

    2015-12-01

    Full Text Available Objective: Medpor is a biocompatible, high-density porous polyethylene implant that is used for multiple indications in plastic surgery. The most frequent complications associated with the Medpor implant are infection and implant exposure. The primary cause of these complications is poor fibrovascularization of the Medpor implant and poor nourishment of the overlying skin. The present experimental study aimed to determine whether vascular endothelial growth factor (VEGF could accelerate and increase Medpor implant fibrovascularization in vivo, and thereby improve local nourishment and prevent complications. Materials and Methods: The Medpor implant was inserted under the dorsal skin area in 40 Sprague-Dawley rats. 20 rats receiving local VEGF injections comprised the study group. The control group received saline injections. Fibrovascularization of the Medpor implants was compared. Results: In the rats injected with VEGF, the Medpor implant fibrovascularized faster, and there were more newly formed blood vessels, as compared with those in the control group. Conclusion: These findings have led to our use of VEGF-like agents that the accelerate angiogenesis in the Medpor implant as a means to reduce the incidence of such complications as infection and implant exposure. [Arch Clin Exp Surg 2015; 4(4.000: 196-201

  19. Nanoscale triboactivity of functionalized c-Si surfaces by Fe+ ion implantation

    Science.gov (United States)

    Nunes, B.; Alves, E.; Colaço, R.

    2016-04-01

    In the present work, we present a study of the effect of Fe+ ion implantation on the tribological response at nanoscale contact lengths of crystalline silicon (c-Si) surfaces. (1 0 0) silicon wafers were implanted with Fe+ at a fluence of 2  ×  1017 cm-2, followed by annealing treatments at temperatures of 800 °C and 1000 °C. After microstructural characterization, nanoabrasive wear tests were performed with an atomic force microscope (AFM) using an AFM diamond tip with a stiff steel cantilever that enables the application of loads between 1 μN and 8 μN. After the nanowear tests, the same AFM was used to visualize and measure the worn craters. It was observed that the as-implanted samples present the poorest nanowear response, i.e. the highest wear rate, even higher than that of the unimplanted Si wafers used as a reference. Nevertheless, annealing treatments result in a measurable increase in the nanowear resistance. In this way we show that Fe+ ion implantation of c-Si, followed by the proper post-heat treatment, results in the formation of FeSi2 nanoprecipitates finely dispersed in a recrystallized matrix. This can be a valuable way of optimizing the nanotribological behavior of silicon.

  20. The effects of high-fat diet on implant osseointegration: an experimental study

    Science.gov (United States)

    2016-01-01

    Objectives In this study, we investigated whether a high-fat diet (HFD) affected the bone implant connection (BIC) in peri-implant bone. Materials and Methods Four male rabbits were used in this study. Dental implant surgery was introduced into each tibia, and four implants were integrated into each animal. In both the normal diet (ND) group (n=2) and HFD group (n=2), 8 implants were integrated, for a total of 16 integrated implants. The animals continued with their respective diets for 12 weeks post-surgery. Afterward, the rabbits were sacrificed, and the BIC was assessed histomorphometrically. Results Histologic and histomorphometric analyses demonstrated that BIC was not impaired in the HFD group compared to the ND group. Conclusion Within the limitations of this study, we found that HFD did not decrease the BIC in rabbit tibias. PMID:27595085

  1. Fabrication and characterization of porous hydroxyapatite ocular implant followed by an in vivo study in dogs

    Indian Academy of Sciences (India)

    B Kundu; M K Sinha; M K Mitra; D Basu

    2004-04-01

    Porous hydroxyapatite ocular implant was fabricated by a novel and simple method using hydroxyapatite powder synthesized in the laboratory. The porosity and pore size of the implant were controlled to make it light in weight as well as suitable for rapid vascularization after implantation. The implant was characterized by X-ray diffraction studies, infrared spectra and chemical analysis for phase purity and chemical composition. The pore morphology and pore size distribution of the samples were investigated by scanning electron microscope (SEM). Thereafter, efficacy of the implant was examined by in vivo study in dogs. Clinical, haematological and radiological studies indicated the suitability of the implant for replacement of the lost eye of human patients.

  2. Correlative Microscopy of Bone in Implant Osteointegration Studies

    Directory of Open Access Journals (Sweden)

    Alessandra Triré

    2010-01-01

    Full Text Available Routine morphological analyses usually include investigations by light microscopy (LM, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. Each of these techniques provides specific information on tissue morphology and all the obtained results are then combined to give an in-depth morphological overview of the examined sample. The limitations of this traditional comparative microscopy lie in the fact that each technique requires a different experimental sample, so that many specimens are necessary and the combined results come from different samples. The present study describes a technical procedure of correlative microscopy, which allows us to examine the same bone section first by LM and then, after appropriate processing, by SEM or TEM. Thanks to the possibility of analyzing the same undecalcified bone sections both by LM and SEM, the approach described in the present study allows us to make very accurate evaluations of old/new bone morphology at the bone-implant interface.

  3. Progenitor Hematopoietic Cells Implantation Improves Functional Capacity of End Stage Coronary Artery Disease Patients with Advanced Heart Failure.

    Science.gov (United States)

    Yuniadi, Yoga; Kusnadi, Yuyus; Sandhow, Lakshmi; Erika, Rendra; Hanafy, Dicky A; Sardjono, Caroline; Kaligis, R W M; Kasim, Manoefris; Harimurti, Ganesja M

    2016-01-01

    Background. Proangiogenic Hematopoietic Cells (PHC) which comprise diverse mixture of cell types are able to secrete proangiogenic factors and interesting candidate for cell therapy. The aim of this study was to seek for benefit in implantation of PHC on functional improvement in end stage coronary artery disease patients with advanced heart failure. Methods. Patients with symptomatic heart failure despite guideline directed medical therapy and LVEF less than 35% were included. Peripheral blood mononuclear cells were isolated, cultivated for 5 days, and then harvested. Flow cytometry and cell surface markers were used to characterize PHC. The PHC were delivered retrogradely via sinus coronarius. Echocardiography, myocardial perfusion, and clinical and functional data were analyzed up to 1-year observation. Results. Of 30 patients (56.4 ± 7.40 yo) preimplant NT proBNP level is 5124.5 ± 4682.50 pmol/L. Harvested cells characterized with CD133, CD34, CD45, and KDR showed 0.87 ± 0.41, 0.63 ± 0.66, 99.00 ± 2.60, and 3.22 ± 3.79%, respectively. LVEF was improved (22 ± 5.68 versus 26.8 ± 7.93, p observation. Myocardial perfusion significantly improved 6 months after treatment. NYHA Class and six-minute walk test are improved during short term and long term follow-up. Conclusion. Expanded peripheral blood PHC implantation using retrograde delivery approach improved LV systolic function, myocardial perfusion, and functional capacity.

  4. Osteoblast integration of dental implant materials after challenge by sub-gingival pathogens : a co-culture study in vitro

    NARCIS (Netherlands)

    Zhao, Bingran; van der Mei, Henny C.; Rustema-Abbing, Minie; Busscher, Henk J.; Ren, Yijin

    2015-01-01

    Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration

  5. Two-stage dental implants inserted in a one-stage procedure : a prospective comparative clinical study

    NARCIS (Netherlands)

    Heijdenrijk, Kees

    2002-01-01

    The results of this study indicate that dental implants designed for a submerged implantation procedure can be used in a single-stage procedure and may be as predictable as one-stage implants. Although one-stage implant systems and two-stage.

  6. Osteoblast integration of dental implant materials after challenge by sub-gingival pathogens : a co-culture study in vitro

    NARCIS (Netherlands)

    Zhao, Bingran; van der Mei, Henny C; Rustema-Abbing, Minie; Busscher, Henk J; Ren, Yijin

    2015-01-01

    Sub-gingival anaerobic pathogens can colonize an implant surface to compromise osseointegration of dental implants once the soft tissue seal around the neck of an implant is broken. In vitro evaluations of implant materials are usually done in monoculture studies involving either tissue integration

  7. Two-stage dental implants inserted in a one-stage procedure : a prospective comparative clinical study

    NARCIS (Netherlands)

    Heijdenrijk, Kees

    2002-01-01

    The results of this study indicate that dental implants designed for a submerged implantation procedure can be used in a single-stage procedure and may be as predictable as one-stage implants. Although one-stage implant systems and two-stage.

  8. Changes in biting forces with implant-supported overdenture in the lower jaw: A comparison between conventional and mini implants in a pilot study.

    Science.gov (United States)

    Hasan, I; Madarlis, C; Keilig, L; Dirk, C; Weber, A; Bourauel, C; Heinemann, F

    2016-11-01

    The biting ability of patients improves noticeably after receiving implant-supported overdentures in comparison to conventional complete dentures. However, the change of biting with such treatment concepts has been quantitatively investigated in only a limited number of studies. The aim of the present study has been to measure the biting forces of edentulous patients with complete dentures and after receiving implant-supported overdentures. A total of 26 edentulous patients were included. Ten patients received two to four conventional implants (control group, Ø3.3-3.7mm, L11-13mm) and 16 patients received four to five mini implants (study group, Ø1.8-2.4mm, L13-15mm) inserted in the mandibular interforaminal region. All patients received a lower overdenture with ball/rubber ring attachments and a complete denture for the maxilla. The biting forces were measured using Prescale pressure sheets type low before the insertion of implants and after receiving implant-supported overdenture. The measured sheets were later scanned and analysed using FPD-8010E software. The range of biting forces before the insertion of implants was 80N-122N for the control group and 66-88N for the study group. After the insertion of implants, the range of biting forces increased to 167N-235N for the control group and to 81N-138N for the study group. However, the increase in biting forces after the insertion of implants was not significant for either group. No significant difference was obtained between the two implant systems. The biting forces improved after insertion of implants regardless of which implant system was used. However, the degree of improvement is noticeably related to the original bone quality of the mandible at the insertion regions of implants.

  9. Functional Near-Infrared Spectroscopy Brain Imaging Investigation of Phonological Awareness and Passage Comprehension Abilities in Adult Recipients of Cochlear Implants

    Science.gov (United States)

    Bisconti, Silvia; Shulkin, Masha; Hu, Xiaosu; Basura, Gregory J.; Kileny, Paul R.; Kovelman, Ioulia

    2016-01-01

    Purpose: The aim of this study was to examine how the brains of individuals with cochlear implants (CIs) respond to spoken language tasks that underlie successful language acquisition and processing. Method: During functional near-infrared spectroscopy imaging, CI recipients with hearing impairment (n = 10, mean age: 52.7 ± 17.3 years) and…

  10. Bone regenerating effect of surface-functionalized titanium implants with sustained-release characteristics of strontium in ovariectomized rats

    Science.gov (United States)

    Offermanns, Vincent; Andersen, Ole Zoffmann; Riede, Gregor; Andersen, Inge Hald; Almtoft, Klaus Pagh; Sørensen, Søren; Sillassen, Michael; Jeppesen, Christian Sloth; Rasse, Michael; Foss, Morten; Kloss, Frank

    2016-01-01

    Since strontium (Sr) is known for its anabolic and anticatabolic effect on bone, research has been focused on its potential impact on osseointegration. The objective of this study was to investigate the performance of nanotopographic implants with a Sr-functionalized titanium (Ti) coating (Ti–Sr–O) with respect to osseointegration in osteoporotic bone. The trial was designed to examine the effect of sustained-release characteristics of Sr in poor-quality bone. Three Ti–Sr–O groups, which differed from each other in coating thickness, Sr contents, and Sr release, were examined. These were prepared by a magnetron sputtering process and compared to uncoated grade 4 Ti. Composition, morphology, and mechanical stability of the coatings were analyzed, and Sr release data were gained from in vitro washout experiments. In vivo investigation was carried out in an osteoporotic rat model and analyzed histologically, 6 weeks and 12 weeks after implantation. Median values of bone-to-implant contact and new bone formation after 6 weeks were found to be 84.7% and 54.9% (best performing Sr group) as compared to 65.2% and 23.8% (grade 4 Ti reference), respectively. The 12-week observation period revealed 84.3% and 56.5% (best performing Sr group) and 81.3% and 39.4% (grade 4 Ti reference), respectively, for the same measurements. The increase in new bone formation was found to correlate with the amount of Sr released in vitro. The results indicate that sputtered nanostructured Ti–Sr–O coatings showed sustained release of Sr and accelerate osseointegration even in poor-quality bone, and thus, may have impact on practical applications for medical implants. PMID:27313456

  11. Non-thermal atmospheric pressure plasma functionalized dental implant for enhancement of bacterial resistance and osseointegration.

    Science.gov (United States)

    Lee, Jung-Hwan; Jeong, Won-Seok; Seo, Seog-Jin; Kim, Hae-Won; Kim, Kyoung-Nam; Choi, Eun-Ha; Kim, Kwang-Mahn

    2017-03-01

    Even though roughened titanium (Ti) and Ti alloys have been clinically used as dental implant, they encourage bacterial adhesion, leading to failure of the initial stability. Here, the non-thermal atmospheric pressure plasma jet (NTAPPJ) functionalized Ti and Ti alloy were investigated to promote cellular activities but inhibit the initial attachment of the adherent pioneer bacterium, Streptococcus sanguinis, without topographical changes. After the produced radicals from NTAPPJ were characterized, bacterial adhesion to specimens was assessed by PrestoBlue assay and live-dead staining with or without the NTAPPJ functionalizing. After the surface was characterized using optical profilometry, X-ray photoelectron spectroscopy and contact angle analysis, the ions released from the specimens were investigated. In vitro initial cell attachment (4h or 24h) with adhesion images and alkaline phosphatase activity (ALP, 14 days) measurements were performed using rat bone marrow-derived mesenchymal stem cells. The initial bacterial adhesion to the Ti and Ti alloy was significantly inhibited after NTAPPJ functionalizing (padhesion-resistance effect was induced by carbon cleaning, which was dependent on the working gas used on the Ti specimens (nitrogen>ammonia and air, padhesion with well-developed vinculin localization and consequent ALP activity at 14days to the NTAPPJ-functionalized specimens were superior to the non-treated specimens. For the promising success of dental implants, NTAPPJ functionalizing is suggested as a novel surface modification technique; this technique can help ensure the success of integration between the dental implants and bone tissues with less concern of inflammation. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  12. Influence of Implant Surface Topography on Primary Stability in a Standardized Osteoporosis Rabbit Model Study

    Directory of Open Access Journals (Sweden)

    Hiroshi Oue

    2015-03-01

    Full Text Available Evaluating primary stability is important to predict the prognosis of dental implant treatment. Primary stability is decreased in a low bone density site such as osteoporosis. However, it is difficult to apply in small animal and the effect of the different implant surface topography for the primary stability at low bone density site has not yet fully been investigated. The purpose of the present study was to evaluate the influence of implant surface topography on primary stability in a standardized osteoporosis animal model. Six rabbits underwent ovariectomy and administrated glucocorticoid to induce an osteoporosis model. Sham-operations were performed in additional six rabbits. Implants with machined or oxidized-surfaces were inserted into the femur epiphyses and insertion torque (IT and implant stability quotient (ISQ were measured. In sham model, the IT and ISQ did not differ significantly between the both implant. However, the IT value of oxidized-surface implant was significantly higher than that of the machined implant in the osteoporosis model. Meanwhile, ISQ did not significantly differ between the machined and oxidized-surfaced implants. In conclusion, the IT of implants is higher with rough than with smooth surfaces but that there are no differences in ISQ value between different surfaces in a standardized osteoporosis bone reduced rabbit model.

  13. Diabetes mellitus and dental implants: a clinical study.

    Science.gov (United States)

    Abdulwassie, Hassan; Dhanrajani, P J

    2002-01-01

    Diabetes mellitus is no longer considered to be a contraindication for implant-supported prostheses, provided that the patient's blood sugar is under control, and that there is motivation for oral hygiene procedures. This paper presents the experiences of treating diabetic patients using implants with good success rates.

  14. [Subperiosteal mandibular implant. Clinical cases and microscopic study].

    Science.gov (United States)

    Rosson, J O

    1990-04-01

    Subperiosteal surgical Vitallium implants have been set in the mandible of patients with loss of height of the osseous ridge and difficulty in the use of prostheses obtaining very good clinical and radiographical results. The optic microscopy showed a great tendency of adhesion of the gingiva's junctional epithelium to the implant.

  15. Microarray expression in peri-implant tissue next to different titanium implant surfaces predicts clinical outcomes: a split-mouth study.

    Science.gov (United States)

    Menini, M; Dellepiane, E; Baldi, D; Longobardi, M G; Pera, P; Izzotti, A

    2017-09-01

    This split-mouth study evaluated miRNA expression of tissues around implants with different surface treatments. Each patient of the sample (five men and five women) received two implants (one control and one test) into an edentulous quadrant to support fixed partial dentures. The control implants (Osseotite) had a dual acid-etched (DAE) surface in the apical portion and a machined coronal part, test implants (Full Osseotite, FOSS) were completely DAE. Machined healing abutments were placed on control implants and DAE abutments on test ones. All implants were assigned codes for blinding. Standardized periapical radiographs were taken at baseline, 2 and 6 months, and 1 year after surgery. Plaque index (PI), bleeding on probing (BOP), and probing depth (PD) were recorded at 3 and 6 weeks, and 2, 3, 6, and 12 months post-implant placement. After 3 months, a mini-invasive sample of soft tissue was collected from seven patients (four women and three men) for miRNA microarray analysis. Control implants showed greater bone resorption (BR) and lower PI: this was not statistically significant. No statistically significant differences in BOP and PD appeared. miRNA modulated by implant surfaces as well as by other clinical conditions has been identified. miRNA microarray analysis revealed that: (i) implant sites with low PI and absence of BOP had a miRNA expression profile similar to those with plaque and absence of BOP; sites with high PI and high BOP had a different profile. (ii) Implant sites with BOP presented similar profiles independently from implant surface. (iii) Implant sites with high PI and normal BR differed from others for miRNA expression profile. (iv) Implant sites with normal BR despite high BOP differed from others. This profile resembled that of FOSS implants. (v) Implant surface affected BR; groups having similar BR clusterized differently according to the implant type. DAE surfaces induced lower BR and more plaque accumulation: This did not affect the

  16. Graphene Functionalized Scaffolds Reduce the Inflammatory Response and Supports Endogenous Neuroblast Migration when Implanted in the Adult Brain.

    Directory of Open Access Journals (Sweden)

    Kun Zhou

    Full Text Available Electroactive materials have been investigated as next-generation neuronal tissue engineering scaffolds to enhance neuronal regeneration and functional recovery after brain injury. Graphene, an emerging neuronal scaffold material with charge transfer properties, has shown promising results for neuronal cell survival and differentiation in vitro. In this in vivo work, electrospun microfiber scaffolds coated with self-assembled colloidal graphene, were implanted into the striatum or into the subventricular zone of adult rats. Microglia and astrocyte activation levels were suppressed with graphene functionalization. In addition, self-assembled graphene implants prevented glial scarring in the brain 7 weeks following implantation. Astrocyte guidance within the scaffold and redirection of neuroblasts from the subventricular zone along the implants was also demonstrated. These findings provide new functional evidence for the potential use of graphene scaffolds as a therapeutic platform to support central nervous system regeneration.

  17. 7-Be Implantation in Plastics for Prosthesis Wear Studies

    Science.gov (United States)

    Greife, Uwe; Erikson, L.; Patel, N.; Wimmer, M.; Dwiwedi, Y.; Laurent, M.; Chipps, K.; Blackmon, J.; Kozub, R.; Bardayan, D.; Gross, C.; Stracener, D.; Smith, M.; Nesaraya, C.; Rehm, E.; Ahmed, I.; Greene, J.

    2010-11-01

    The current generation of highly cross linked ultrahigh molecular weight polyethylenes (PE) for hip and knee joint replacement have achieved such low in vitro wear rates that efforts have been underway to develop more sensitive methods to measure polyethylene wear. The most widely used technique, the gravimetric method, suffers from the notable disadvantage that mass gain by fluid absorption can considerably exceed mass loss by wear, making the wear measurement inaccurate, sometimes even leading to negative ``wear'' values. The purpose of this experiment was to investigate the use of a radioactive tracer, beryllium-7 (7-Be), to circumvent the problem of fluid absorption and thereby achieve a much more sensitive and accurate wear measurement. This proof of principle study demonstrated the general feasibility of 7-Be implantation (performed at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory) for PE wear analysis.

  18. Patient satisfaction relating to implant treatment by undergraduate and postgraduate dental students--a pilot study.

    LENUS (Irish Health Repository)

    Harrison, P

    2009-08-01

    Recordings of patient satisfaction with provision of dental implant treatment are scarce. This study aimed to evaluate satisfaction amongst patients attending for provision of implant treatment by training undergraduate and postgraduate students at Dublin Dental School and Hospital (DDSH). A questionnaire was formulated and distributed to 100 individuals randomly selected from records of patients who had received implant treatment via student clinics in the previous 5 years. The response rate was 68%. Results showed a high overall level of satisfaction with treatment received.

  19. Study of defects in implanted silica glass by depth profiling Positron Annihilation Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Brusa, R.S., E-mail: brusa@science.unitn.i [CNISM, Dipartimento di Fisica, Universita di Trento, Via Sommarive 14, I-38050 Povo, Trento (Italy); Mariazzi, S. [CNISM, Dipartimento di Fisica, Universita di Trento, Via Sommarive 14, I-38050 Povo, Trento (Italy); Ravelli, L. [CNISM, Dipartimento di Fisica, Universita di Trento, Via Sommarive 14, I-38050 Povo, Trento (Italy); Institut fuer Angewandte Physik und Messtechnik, Universitaet der Bunderswehr Muenchen, 85577 Neubiberg (Germany); Mazzoldi, P.; Mattei, G. [CNISM, Dipartimento di Fisica, Universita di Padova, Via Marzolo 8, 35131 Padova (Italy); Egger, W. [Institut fuer Angewandte Physik und Messtechnik, Universitaet der Bunderswehr Muenchen, 85577 Neubiberg (Germany); Hugenschmidt, C.; Loewe, B.; Pikart, P. [Physik Department E21 and FRMII, Technische Universitaet Muenchen, 85747 Garching (Germany); Macchi, C.; Somoza, A. [IFIMAT, UNCentro and CICPBA, Pinto 399, B7000GHG Tandil (Argentina)

    2010-10-01

    Positron Annihilation Spectroscopy (PAS) performed with continuous and pulsed positron beams allows to characterize the size of the intrinsic nano-voids in silica glass, their in depth modification after ion implantation and their decoration by implanted ions. Three complementary PAS techniques, lifetime spectroscopy (LS), Doppler broadening spectroscopy (DBS) and coincidence Doppler broadening spectroscopy (CDBS) will be illustrated by presenting, as a case study, measurements obtained on virgin and gold implanted silica glass.

  20. No effect of hydroxyapatite particles in phagocytosable sizes on implant fixation: an experimental study in dogs

    DEFF Research Database (Denmark)

    Rahbek, O; Kold, S; Bendix, K

    2005-01-01

    The influence of wear debris on bone healing around orthopedic implants is debated. Hydroxyapatite (HA) particles and polyethylene (PE) particles have been shown to have a negative effect on osteoblast cultures in vitro. The present study investigated the in vivo effects of HA and PE particles on....... HA particles were also integrated in newly formed bone. We found no negative effect of the particulate material on mechanical fixation of the implants or on bone formation around the implants....

  1. A CLINICAL STUDY ON THE INCIDENCE AND MANAGEMENT OF BIOLOGICAL COMPLICATIONS IN IMPLANT THERAPY

    Directory of Open Access Journals (Sweden)

    Nicolae VASILE

    2015-09-01

    Full Text Available The scope of the study was to evidence the methods recommended for avoiding, managing and implementing an efficient treatment capable of reducing the biological complications accompanying implant therapies. Materials and method. The study evaluates the patients with prosthesis charged implants - or during their osseointegration period - inserted in the Clinic of The Emergency Military Hospital of Sibiu, over a 5 year period (2009-2014. Retrospective investigation was based on the evaluation of the treatment files and on the imagistic and clinical analyses of the 125 patients to whom 385 implants had been inserted. Results and discussion. The study demonstrates that, when implants are the support of an overdenture, surrounded by either limited keratinized gingiva or mobile tissues, the presence of the bacterial plaque is considerable, the peri-implant pocket exceeds 5 mm, and sensitivity and bleeding are produced on contact with the probe. In susceptible patients, or in those with pathological periodontal antecedents, the re-infection potential has been always higher. The clinical study confirms that, invariably, peri-implantitis is associated with the existence of the bacterial plaque and also with the presence of a peri-implant pocket exceeding 4 mm (8.9%, with partial exposure of the covering screw (4.5% and fixed restaurations without self-cleaning spaces (2%. Conclusions. Out of the post-surgery biological complications, peri-implantitis is the most frequent one, causing a – sometimes total – loss of the alveolar bone around the osseointegrated implant.

  2. An Ex Vivo Model in Human Femoral Heads for Histopathological Study and Resonance Frequency Analysis of Dental Implant Primary Stability

    Directory of Open Access Journals (Sweden)

    Pedro Hernández-Cortés

    2014-01-01

    Full Text Available Objective. This study was designed to explore relationships of resonance frequency analysis (RFA—assessed implant stability (ISQ values with bone morphometric parameters and bone quality in an ex vivo model of dental implants placed in human femoral heads and to evaluate the usefulness of this model for dental implant studies. Material and Methods. This ex vivo study included femoral heads from 17 patients undergoing surgery for femoral neck fracture due to osteoporosis (OP (n=7 or for total prosthesis joint replacement due to severe hip osteoarthrosis (OA (n=10. Sixty 4.5×13 mm Dentsply Astra implants were placed, followed by RFA. CD44 immunohistochemical analysis for osteocytes was also carried out. Results. As expected, the analysis yielded significant effects of femoral head type (OA versus OA (P0.5 in all cases, and no significant differences in ISQ values were found as a function of the length or area of the cortical layer (both P>0.08. Conclusion. Although RFA-determined ISQ values are not correlated with morphometric parameters, they can discriminate bone quality (OP versus OA. This ex vivo model is useful for dental implant studies.

  3. Enhanced Flexible Tubular Microelectrode with Conducting Polymer for Multi-Functional Implantable Tissue-Machine Interface

    Science.gov (United States)

    Tian, Hong-Chang; Liu, Jing-Quan; Kang, Xiao-Yang; Tang, Long-Jun; Wang, Ming-Hao; Ji, Bo-Wen; Yang, Bin; Wang, Xiao-Lin; Chen, Xiang; Yang, Chun-Sheng

    2016-05-01

    Implantable biomedical microdevices enable the restoration of body function and improvement of health condition. As the interface between artificial machines and natural tissue, various kinds of microelectrodes with high density and tiny size were developed to undertake precise and complex medical tasks through electrical stimulation and electrophysiological recording. However, if only the electrical interaction existed between electrodes and muscle or nerve tissue without nutrition factor delivery, it would eventually lead to a significant symptom of denervation-induced skeletal muscle atrophy. In this paper, we developed a novel flexible tubular microelectrode integrated with fluidic drug delivery channel for dynamic tissue implant. First, the whole microelectrode was made of biocompatible polymers, which could avoid the drawbacks of the stiff microelectrodes that are easy to be broken and damage tissue. Moreover, the microelectrode sites were circumferentially distributed on the surface of polymer microtube in three dimensions, which would be beneficial to the spatial selectivity. Finally, the in vivo results confirmed that our implantable tubular microelectrodes were suitable for dynamic electrophysiological recording and simultaneous fluidic drug delivery, and the electrode performance was further enhanced by the conducting polymer modification.

  4. Five-year clinical and functional multislice computed tomography angiographic results after coronary implantation of the fully resorbable polymeric everolimus-eluting scaffold in patients with de novo coronary artery disease

    DEFF Research Database (Denmark)

    Onuma, Yoshinobu; Dudek, Dariusz; Thuesen, Leif

    2013-01-01

    This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California).......This study sought to demonstrate the 5-year clinical and functional multislice computed tomography angiographic results after implantation of the fully resorbable everolimus-eluting scaffold (Absorb BVS, Abbott Vascular, Santa Clara, California)....

  5. Study of the effects of focused high-energy boron ion implantation in diamond

    Science.gov (United States)

    Ynsa, M. D.; Agulló-Rueda, F.; Gordillo, N.; Maira, A.; Moreno-Cerrada, D.; Ramos, M. A.

    2017-08-01

    Boron-doped diamond is a material with a great technological and industrial interest because of its exceptional chemical, physical and structural properties. At modest boron concentrations, insulating diamond becomes a p-type semiconductor and at higher concentrations a superconducting metal at low temperature. The most conventional preparation method used so far, has been the homogeneous incorporation of boron doping during the diamond synthesis carried out either with high-pressure sintering of crystals or by chemical vapour deposition (CVD) of films. With these methods, high boron concentration can be included without distorting significantly the diamond crystalline lattice. However, it is complicated to manufacture boron-doped microstructures. A promising alternative to produce such microstructures could be the implantation of focused high-energy boron ions, although boron fluences are limited by the damage produced in diamond. In this work, the effect of focused high-energy boron ion implantation in single crystals of diamond is studied under different irradiation fluences and conditions. Micro-Raman spectra of the sample were measured before and after annealing at 1000 °C as a function of irradiation fluence, for both superficial and buried boron implantation, to assess the changes in the diamond lattice by the creation of vacancies and defects and their degree of recovery after annealing.

  6. Study of shallow and deep damage in Cu and Al after self-implantation

    Energy Technology Data Exchange (ETDEWEB)

    Lindgreen, R.J.Th.; Boerma, D.O.; de Hosson, J.Th.M. (Rijks-universiteit Groningen (Netherlands). Materials Science Centre)

    1983-05-01

    The damage formed by self-implantation in Cu and Al at two temperatures, where vacancies are considered to be either immobile or mobile, but where interstitials are always highly mobile, is studied before and after annealing, using dechanneling methods. Two different regions of damage are distinguished: a surface region coinciding with the projected range of the implanted self-ions, and a region extending up to 10 times beyond this range. On the basis of differences on the formation of the deep and the shallow damage as a function of implantation temperature and a different behaviour of annealing it is concluded that the two regions contain different types of damage. A mechanism is proposed that explains the observed damage distributions qualitatively. In this model the damage in the surface region of copper is assumed to consist of mainly clusters of vacancies. In the deep region of copper and aluminium it is assumed that the damage consists of clusters or loops formed by interstitials.

  7. Study of the feasible size of a bone conduction implant transducer in the temporal bone.

    Science.gov (United States)

    Reinfeldt, Sabine; Östli, Per; Håkansson, Bo; Taghavi, Hamidreza; Eeg-Olofsson, Måns; Stalfors, Joacim

    2015-04-01

    The aim was to assess the temporal bone volume to determine the suitable size and position of a bone conduction implant (BCI) transducer. A BCI transducer needs to be sufficiently small to fit in the mastoid portion of the temporal bone for a majority of patients. The anatomical geometry limits both the dimension of an implanted transducer and its positions in the temporal bone to provide a safe and simple surgery. Computed tomography (CT) scans of temporal bones from 22 subjects were virtually reconstructed. With an algorithm in MATLAB, the maximum transducer diameter as function of the maximum transducer depth in the temporal bone, and the most suitable position were calculated in all subjects. An implanted transducer diameter of 16 mm inserted at a depth of 4 mm statistically fitted 95% of the subjects. If changing the transducer diameter to 12 mm, a depth of 6 mm would fit in 95% of the subjects. The most suitable position was found to be around 20 mm behind the ear canal. The present BCI transducer casing, used in ongoing clinical trials, was designed from the results in this study, demonstrating that the present BCI transducer casing (largest diameter [diagonal]: 15.5 mm, height: 6.4 mm) will statistically fit more than 95% of the subjects. Hence, the present BCI transducer is concluded to be sufficiently small to fit most normal-sized temporal bones and should be placed approximately 20 mm behind the ear canal.

  8. Characterization and simulation studies on high tilt ion implantation for precision halo implant applications

    Energy Technology Data Exchange (ETDEWEB)

    Guo, B.N. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States)]. E-mail: baonian.guo@vsea.com; Zhao, Z.Y. [Spansion LLC, 5204 E. Ben White Blvd., Austin, TX 78741 (United States); Falk, S. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States); Liu, J. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States); Shim, K.H. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States); Jeong, U. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States); Mehta, S. [Varian Semiconductor Equipment Associates, Inc., 35 Dory Road, Gloucester, MA 01930 (United States)

    2007-08-15

    Precision dopant placement at high tilt angles for halo applications is required in the fabrication of advanced devices to achieve better transistor characteristics, such as suppression of short channel effects, V {sub t} control and drive current. However, monitoring high tilt implants is not popular in semiconductor fabs, even though most have started monitoring zero-tilt implants in the recent couple of years. In this paper, the authors explore the possibilities of using high tilt angles with higher Miller Index channels. As an example, axial channeling along the <1 1 2> direction is used to evaluate the angle control performance of the VIISta 810EHP medium current ion implanter. Crystal-TRIM (a Monte Carlo simulation code) calculations are compared with experimental SIMS (Secondary Ion Mass Spectrometry) profiles. In addition, the effects of wafer orientation on the platen and wafer mis-cut on the dopant profiles are discussed. Metrology characterization, such as ThermaWave{sup TM} and SIMS, of the <1 1 2> ion channeling is presented.

  9. Pectin nanocoating of titanium implant surfaces - an experimental study in rabbits

    DEFF Research Database (Denmark)

    Gurzawska, Katarzyna Aleksandra; Dirscherl, Kai; Jørgensen, Bodil

    2017-01-01

    INTRODUCTION: A major determinant of successful osseointegration of endosseous implants is the surface of the implant, which influences the cellular response of the surrounding tissues. A new strategy to improve osseointegration and bone healing is biochemical stimulation by surface nanocoatings...... that may increase adhesion of bone proteins, and bone cells at the implant surface. Nanocoating with pectins, plant cell wall-derived polysaccharides, is frequently done using rhamnogalacturonan-I (RG-I). AIM: The aim of the study was to evaluate the effect of nanocoating titanium implants with plant cell...... wall-derived rhamnogalacturonan-I, on bone healing and osseointegration. MATERIAL AND METHODS: Machined titanium implants were coated with three modifications of rhamnogalacturonan-I (RG-I). Chemical and physical surface properties were examined before insertion of nanocoated implants (n = 96...

  10. A comparative study of zirconium and titanium implants in rat: osseointegration and bone material quality.

    Science.gov (United States)

    Hoerth, Rebecca M; Katunar, María R; Gomez Sanchez, Andrea; Orellano, Juan C; Ceré, Silvia M; Wagermaier, Wolfgang; Ballarre, Josefina

    2014-02-01

    Permanent metal implants are widely used in human medical treatments and orthopedics, for example as hip joint replacements. They are commonly made of titanium alloys and beyond the optimization of this established material, it is also essential to explore alternative implant materials in view of improved osseointegration. The aim of our study was to characterize the implant performance of zirconium in comparison to titanium implants. Zirconium implants have been characterized in a previous study concerning material properties and surface characteristics in vitro, such as oxide layer thickness and surface roughness. In the present study, we compare bone material quality around zirconium and titanium implants in terms of osseointegration and therefore characterized bone material properties in a rat model using a multi-method approach. We used light and electron microscopy, micro Raman spectroscopy, micro X-ray fluorescence and X-ray scattering techniques to investigate the osseointegration in terms of compositional and structural properties of the newly formed bone. Regarding the mineralization level, the mineral composition, and the alignment and order of the mineral particles, our results show that the maturity of the newly formed bone after 8 weeks of implantation is already very high. In conclusion, the bone material quality obtained for zirconium implants is at least as good as for titanium. It seems that the zirconium implants can be a good candidate for using as permanent metal prosthesis for orthopedic treatments.

  11. Efficacy and safety of a diode laser in second-stage implant surgery: a comparative study.

    Science.gov (United States)

    El-Kholey, K E

    2014-05-01

    For more than a decade, peri-implant tissues have been treated with soft tissue lasers to create a bloodless flap for implant placement and to uncover implants with minimal bleeding, trauma, and anaesthesia. This study was designed to assess if dental implant uncovering is possible with a diode laser without anaesthesia, and to compare its performance with traditional cold scalpel surgery. Thirty patients with a total of 45 completely osseointegrated implants participated in this study. Patients were divided into two groups. For the study group, second-stage implant surgery was done with a 970nm diode laser. For the control group, the implants were exposed with a surgical blade. Certain parameters were used for evaluation of the two techniques. The use of the diode laser obviated the need for local anaesthesia; there was a significant difference between the two groups regarding the need for anaesthesia (Pdiode laser can be used effectively for second-stage implant surgery, providing both the dentist and the patient with additional advantages over the conventional methods used for implant exposure.

  12. Changes in Crestal Bone Around Endosseous Implants During Functional Loading : A Radiographic Evaluation in Edentulous Patients Comparing Different Implant Designs

    NARCIS (Netherlands)

    Tymstra, N.; Meijer, H.J.A.; Raghoebar, G.M.; Vissink, A.

    2012-01-01

    Marginal bone changes around titanium plasma-sprayed implants (n = 240) placed in the mandibular interforaminal regions of 120 edentulous patients were assessed over 5 years of follow-up, with emphasis on the influence of the locations of the microgap and rough/smooth border. Marginal bone changes w

  13. Speech and language skills of Maltese children with bilateral cochlear implants : three case studies

    OpenAIRE

    2014-01-01

    The purpose of this study was to document the speech and language skills of three Maltese children with bilateral cochlear implants. One child was simultaneously implanted and had a hearing age (HA) of 2;10 years at the time of testing, another was sequentially implanted and had a HA of 3;06 years, while the third child was sequentially implanted and had a HA of 5;03 years. Maltese standardised speech and language assessments were used to gather information on the childre...

  14. Experimental studies of N~+ implantation into CVD diamond thin films

    Institute of Scientific and Technical Information of China (English)

    辛火平; 林成鲁; 王建新; 邹世昌; 石晓红; 林梓鑫; 周祖尧; 刘祖刚

    1997-01-01

    The effects of N+ implantation under various conditions on CVD diamond films were analyzed with Raman spectroscopy, four-point probe method, X-ray diffraction (XRD), Rutherford backseattering spectroscopy (RBS), ultraviolet photoluminescence spectroscopy (UV-PL), Fourier transformation infrared absorption spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results show that the N+ implantation doping without any graphitization has been successfully realized when 100 keV N+ ions at a dosage of 2 × 1016 cm-2 were implanted into diamond films at 550℃ . UV-PL spectra indicate that the implanted N+ ions formed an electrically inactive deep-level impurity in diamond films. So the sheet resistance of the sample after N+ implantation changed little. Carbon nitride containing C≡N covalent bond has been successfully synthesized by 100 keV, 1.2×1018 N/cm2 N+ implantation into diamond films. Most of the implanted N+ ions formed C≡N covalent bonds with C atoms. The others were free state nitroge

  15. Titanium coated with functionalized carbon nanotubes — A promising novel material for biomedical application as an implantable orthopaedic electronic device

    Energy Technology Data Exchange (ETDEWEB)

    Przekora, Agata, E-mail: agata.przekora@umlub.pl [Department of Biochemistry and Biotechnology, Medical University of Lublin, Faculty of Pharmacy with Medical Analytics Division, Chodzki 1, 20-093 Lublin (Poland); Benko, Aleksandra; Nocun, Marek; Wyrwa, Jan; Blazewicz, Marta [Faculty of Materials Science and Ceramics, AGH-Univ. of Science and Technology, A. Mickiewicz 30 Ave., 30-059 Cracow (Poland); Ginalska, Grazyna [Department of Biochemistry and Biotechnology, Medical University of Lublin, Faculty of Pharmacy with Medical Analytics Division, Chodzki 1, 20-093 Lublin (Poland)

    2014-12-01

    The aim of the study was to fabricate titanium (Ti) material coated with functionalized carbon nanotubes (f-CNTs) that would have potential medical application in orthopaedics as an implantable electronic device. The novel biomedical material (Ti-CNTs-H{sub 2}O) would possess specific set of properties, such as: electrical conductivity, non-toxicity, and ability to inhibit connective tissue cell growth and proliferation protecting the Ti-CNTs-H{sub 2}O surface against covering by cells. The novel material was obtained via an electrophoretic deposition of CNTs-H{sub 2}O on the Ti surface. Then, physicochemical, electrical, and biological properties were evaluated. Electrical property evaluation revealed that a Ti-CNTs-H{sub 2}O material is highly conductive and X-ray photoelectron spectroscopy analysis demonstrated that there are mainly COOH groups on the Ti-CNTs-H{sub 2}O surface that are found to inhibit cell growth. Biological properties were assessed using normal human foetal osteoblast cell line (hFOB 1.19). Conducted cytotoxicity tests and live/dead fluorescent staining demonstrated that Ti-CNTs-H{sub 2}O does not exert toxic effect on hFOB cells. Moreover, fluorescence laser scanning microscope observation demonstrated that Ti-CNTs-H{sub 2}O surface retards to a great extent cell proliferation. The study resulted in successful fabrication of highly conductive, non-toxic Ti-CNTs-H{sub 2}O material that possesses ability to inhibit osteoblast proliferation and thus has a great potential as an orthopaedic implantable electronic device. - Highlights: • Functionalized carbon nanotubes were electrophoretically deposited on Ti surface. • Physicochemical, electrical, and biological properties were evaluated. • Ti-CNTs-H{sub 2}O is highly conductive and there are mainly COOH groups on its surface. • Novel material is non-toxic and retards to a great extent osteoblast proliferation. • Ti-CNTs-H{sub 2}O has a promising potential as implantable orthopaedic

  16. Health-related quality of life, visual function and treatment satisfaction following intravitreal dexamethasone implant for diabetic macular edema

    Science.gov (United States)

    Ramu, Jayashree; Chatziralli, Irini; Yang, Yit; Menon, Geeta; Bailey, Clare; Eckstein, Michael; Hykin, Phil; Sivaprasad, Sobha

    2017-01-01

    Purpose The aim of this study was to explore and describe quantitatively patient-reported outcome measures (PROMs), ie, health-related quality of life (QoL), visual function and treatment satisfaction, in patients with diabetic macular edema (DME) receiving two different regimens of Ozurdex (intravitreal dexamethasone implant). Methods In this multicenter, prospective study, 100 patients with center-involving refractory DME were randomized 1:1 to either five monthly fixed dosing or optical coherence tomography (OCT)-guided pro re nata (PRN) regimen of dexamethasone intravitreal implant therapy. The primary outcome was the difference between arms in change in PROMs and health-related QoL from baseline to 12 months, as measured by the Retinopathy-Dependent Quality of Life (RetDQoL) questionnaire, Visual Function Questionnaire-25 (VFQ-25) and Retinopathy Treatment Satisfaction Questionnaire (RetTSQ). Results There was no statistically significant difference in the RetDQoL score and VFQ-25 score at month 12 compared to those at baseline, whereas the total mean RetTSQ score increased significantly at the exit visit. The two treatment arms did not differ significantly regarding the change in PROMs and health-related QoL questionnaires. Logistic regression analysis showed that visual acuity (VA) of ≥55 letters, central foveal thickness statistically significant improvement in treatment satisfaction, as measured by RetTSQ, in patients with DME treated with dexamethasone intravitreal implant, independent of the dose regimen, namely, fixed or PRN. However, it should be noted that the clinically meaningful change could not be assessed accurately, since no thresholds for clinically meaningful change currently exist for the RetTSQ. On the other hand, there was no significant change in health-related QoL, as measured using VFQ-25 and RetDQoL. Factors affecting the patients’ treatment satisfaction were the final VA, the central foveal thickness and the macular volume. PMID

  17. Anchorage of TiO2-blasted, HA-coated, and machined implants: an experimental study with rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Wennerberg, A; Johansson, C

    1995-01-01

    The purpose of this study was to evaluate the histometrical and biomechanical anchorage of TiO2-blasted implants and TiO2-blasted implants coated with hydroxyapatite. The control implants were machined. Twenty-six rabbits had a total of 156 implants placed in the proximal part of the tibia. Each...... rabbit had a machined, a TiO2-blasted, and a TiO2-blasted, HA-coated implant placed in each tibia. After a healing period of 3 and 12 weeks, respectively, the implants placed in the right tibia were used for removal torque test, and the implants placed in the left tibia were used for histomorphometrical...... measurements. Preoperatively, implants from the same batches were examined topographically with a TopScan 3D system. The TiO2-blasted implants demonstrated significantly higher removal torque values than the machined implants, and they also had a significantly more irregular surface. Furthermore, significantly...

  18. Strains around distally inclined implants retaining mandibular overdentures with Locator attachments: an in vitro study

    Science.gov (United States)

    Setta, Fathi Abo; Khirallah, Ahmed Samir

    2016-01-01

    PURPOSE The aim of the present study was to evaluate, by means of strain gauge analysis, the effect of different implant angulations on strains around two implants retaining mandibular overdenture with Locator attachments. MATERIALS AND METHODS Four duplicate mandibular acrylic models were constructed. Two implants were inserted in the canine regions using the following degrees of distal inclinations: group I (control); 0°, group II; 10°, group III; 20°, and group IV; 30°. Locator pink attachments were used to connect the overdenture to the implants and Locator red (designed for severely angled implants) was used for group IV (group IVred). For each group, two linear strain gauges were attached at the mesial and distal surfaces of the acrylic resin around each implant. Peri-implant strain was measured on loading and non-loading sides during bilateral and unilateral loading. RESULTS For all groups, the mesial surfaces of the implants at loading and non-loading sides experienced compressive (negative) strains, while the distal implant surfaces showed tensile (positive) strains. Group IV showed the highest strain, followed by group III, group II. Both group I and group IVred showed the lowest strain. The strain gauges at the mesial surface of the loading side recorded the highest strain, and the distal surface at non-loading side showed the lowest strain. Unilateral loading recorded significantly higher strain than bilateral loading. CONCLUSION Peri-implant strains around two implants used to retain mandibular overdentures with Locator attachments increase as distal implant inclination increases, except when red nylon inserts were used. PMID:27141255

  19. Stress distribution in implant retained finger prosthesis: a finite element study.

    Science.gov (United States)

    Amornvit, Pokpong; Rokaya, Dinesh; Keawcharoen, Konrawee; Thongpulsawasdi, Nimit

    2013-12-01

    Finger amputation may result from congenital cause, trauma, infection and tumours. The finger amputation may be rehabilitated with dental implant-retained finger prosthesis. The success of implant-retained finger prosthesis is determined by the implant loading. The type of the force is a determining factor in implant loading. To evaluate stress distributions in finger bone when the loading force is applied along the long axis of the implant using finite element analysis. The finite element models were created. The finger bone model containing cortical bone and cancellous bone was constructed by using radiograph. Astra Tech Osseo Speed bone level implant of 4.5 mm diameter and 14 mm length was selected. The force was applied to the top of the abutment along the long axis of the implant. Finite element analysis indicated that the maximum stress was located at the head of abutment screw. The minimum stress was located in the apical third of the implant fixture. The weakest point was calculated by safety factor which is located in the spongy bone at apical third of the fixtures. Finally, 4.9 times yield stress of spongy bone was needed for the deformation of the spongy bone. Finite element study showed that when the force was applied along the long axis of the implant, the maximum stress was located around the neck of the implant and the cortex bone received more stress than cancellous bone. So, to achieve long term success, the designers of implant systems must confront biomaterial and biomechanical problems including in vivo forces on implants, load transmission to the interface and interfacial tissue response.

  20. Christensen vs Biomet Microfixation alloplastic TMJ implant: Are there improvements? A numerical study.

    Science.gov (United States)

    Ramos, António; Mesnard, Mesnard

    2015-10-01

    The objective of this study was to compare the load transfer mechanism and behavior of two total temporomandibular joint (TMJ) prostheses: Biomet and Christensen TMJ models were simulated. Computed tomography (CT) images from a specific patient were used to generate two models for use in simulation of implantation for the total temporomandibular prostheses. Three finite element models were created in all. One considered the intact temporomandibular joint and two received a temporomandibular implant. In the simulation we considered the five most important muscles acting on the mandible and incisor teeth support. The Christensen model reduced strain in the opposite condyle by around 50% while increasing strain in the implanted condyle. The changes in the posterior side of the implanted condyle present an increase of five times the minimum principal strain, suggesting some bone fatigue. With the Biomet implant, the reduction in strain in the implanted condyle on the posterior side was around 100%, suggesting the possibility of some bone loss proximally near the resection plane. Based on our results, we conclude that in both models the implants influence the behavior of the mandible by improving the symmetry of the mandible and strain distribution. The Biomet implant modifies the behavior of the mandible slightly and presents some improvements over the Christensen TMJ model in strain distribution and tensions in the opposite intact disc similar to the non-implanted situation.

  1. In vitro study of 980nm diode laser in dental implant disinfection

    Directory of Open Access Journals (Sweden)

    Fábio Gonçalves

    2009-12-01

    Full Text Available Objective: To evaluate the potential of 980nm diode laser to reduce bacteria after irradiation of three different dental implant surfaces contaminated with Enterococcus faecalis and Porphyromonas gingivalis, as well as the possible changes in the irradiated implant surfaces.Methods: Seventy two implants with machined surfaces, airborne particle abraded with titanium oxide and acid-etched surfaces were exposed to Enterococcus faecalis and Porphyromonas gingivalis cultures and irradiated with 980nm diode laser with power of 2.5 and 3,0W. After laser treatments, the number of remaining colony-forming units was studied and implant surface morphology was analyzed by scanning electron microscopy. Results: The results showed 100% reduction of the bacteria on the implants irradiated with 3.0W. Moreover, 100% reduction of bacteria was also achieved on the implant surfaces contaminated with Porphyromonas gingivalis when irradiated with 2.5W and 3.0W. Bacteria reduction was not complete for the implants contaminated with Enterococcus faecalis, irradiated with 2.5W and surfaces treated with TiO2 airborne particle abrasion (78.6% and acid etching (49.4%.The scanning electron microscopy analysis showed that at the power settings used, no implant surface changes were found. Conclusion: The 980nm diode laser was effective in decontaminating the Enterococcus faecalis and Porphyromonas gingivalis without promoting surface alteration in the implants.

  2. Maxillary overdentures supported by four splinted direct metal laser sintering implants: a 3-year prospective clinical study.

    Science.gov (United States)

    Mangano, Francesco; Luongo, Fabrizia; Shibli, Jamil Awad; Anil, Sukumaran; Mangano, Carlo

    2014-01-01

    Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS) technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females) to support bar-retained maxillary overdentures (ODs). Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB). Results. The 3-year implant survival rate was 97.4% (implant-based) and 92.9% (patient-based). Three implants failed. The incidence of biological complication was 3.5% (implant-based) and 7.1% (patient-based). The incidence of prosthetic complication was 17.8% (patient-based). No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results.

  3. Maxillary Overdentures Supported by Four Splinted Direct Metal Laser Sintering Implants: A 3-Year Prospective Clinical Study

    Directory of Open Access Journals (Sweden)

    Francesco Mangano

    2014-01-01

    Full Text Available Purpose. Nowadays, the advancements in direct metal laser sintering (DMLS technology allow the fabrication of titanium dental implants. The aim of this study was to evaluate implant survival, complications, and peri-implant marginal bone loss of DMLS implants used to support bar-retained maxillary overdentures. Materials and Methods. Over a 2-year period, 120 implants were placed in the maxilla of 30 patients (18 males, 12 females to support bar-retained maxillary overdentures (ODs. Each OD was supported by 4 implants splinted by a rigid cobalt-chrome bar. At each annual follow-up session, clinical and radiographic parameters were assessed. The outcome measures were implant failure, biological and prosthetic complications, and peri-implant marginal bone loss (distance between the implant shoulder and the first visible bone-to-implant contact, DIB. Results. The 3-year implant survival rate was 97.4% (implant-based and 92.9% (patient-based. Three implants failed. The incidence of biological complication was 3.5% (implant-based and 7.1% (patient-based. The incidence of prosthetic complication was 17.8% (patient-based. No detrimental effects on marginal bone level were evidenced. Conclusions. The use of 4 DMLS titanium implants to support bar-retained maxillary ODs seems to represent a safe and successful procedure. Long-term clinical studies on a larger sample of patients are needed to confirm these results.

  4. Bicuspid pulmonary valve implantation using polytetrafluoroethylene membrane: early results and assessment of the valve function by magnetic resonance imaging.

    Science.gov (United States)

    Lee, Cheul; Lee, Chang-Ha; Kwak, Jae Gun; Song, Jin Young; Shim, Woo-Sup; Choi, Eun Young; Lee, Sang Yun; Kim, Yang Min

    2013-03-01

    The durability of bioprosthetic valves in the pulmonary position is suboptimal. The objectives of this study were to evaluate the early results of polytetrafluoroethylene (PTFE) bicuspid pulmonary valve (PV) implantation and to better define the function of this valve by magnetic resonance imaging (MRI). Fifty-six patients who underwent PTFE bicuspid PV implantation between June 2009 and August 2011 were retrospectively analysed. The median age was 17.5 years and median valve size was 26 mm. Fundamental diagnoses were tetralogy of Fallot (n = 38), pulmonary atresia with ventricular septal defect (n = 8), double outlet right ventricle (n = 7) and absent PV syndrome (n = 3). Thirty-two patients with pulmonary regurgitation (PR) underwent MRI preoperatively and 22 of them underwent follow-up MRI at a median of 6.7 months postoperatively. There was one early death. Postoperative echocardiography (n = 53) showed no or trivial PR in 49 patients and mild PR in 4. Median follow-up duration was 15.2 months. There was no late death or reoperation. Follow-up echocardiography (n = 41) performed at a median of 7.5 months postoperatively showed no or trivial PR in 33 patients and mild PR in 8 patients. Follow-up MRI showed a significant reduction in right ventricular volumes and improvement in biventricular function. The median PR fraction of this valve was 10%. Early results of bicuspid PV implantation using PTFE membrane were satisfactory. PTFE bicuspid PV demonstrated excellent performance for the short term as evidenced by echocardiography and MRI. Long-term follow-up is mandatory to determine the durability of this valve.

  5. Immediate occlusal loading of Tapered Internal Laser-Lok® implants in partial arch rehabilitations: a 24-months clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    M. Grande

    2013-10-01

    Full Text Available Aim The purpose of this 2 year prospective clinical study was to clinically and radiographically evaluate an implant with laser microtextured collar surface placed for immediate loading of fixed prostheses in cases of partial posterior maxillary and/or mandibular edentulism.Materials and methods Thirty-five partially edentulous patients who needed implant treatment and met inclusion criterias were consecutively enrolled at different study-centers in Italy. A total of 107 Tapered Internal Laser-Lok® implants (49 maxillary and 58 mandibular were placed and immediately loaded. All provisional constructions were delivered within 1 hour, and the final constructions placed after 4 months. A total of 107 Tapered Internal Laser-Lok implants (49 maxillary and 58 mandibular were placed and immediately loaded. All provisional restorations were delivered within 1 hour, and the final prosthesis placed after 4 months. A total of 32 prosthetic restorations, consisting of 10 two- units, 12 three-units, and 10 four-units fixed partial dentures were evaluated. Clinical and radiographic outcomes were monitored at follow-up examinations scheduled 6, 12, 24 months after implants placement.Results Five implants were lost after loading (3 implants in a two-unit maxillary restorations, 1 implant in a two-unit mandibular restorations, and 1 implant in three-unit maxillary restorationsgiving a survival rate of 95.4% after 24 months. Mean crestal bone loss at 6, 12, and 24 months after implant insertion was 0.42 +/- 1.1 mm, 0.52 +/- 0.9 mm, and 0.66 +/- 1.3 mm, respectively.Conclusion Although limited bytheshort follow-up, immediate function with Tapered Internal Laser-Lok® implants seems to be a viable option to treat partially edentulous patients.

  6. Evaluation of implant osseointegration success: Retrospective study at update course

    OpenAIRE

    Moraes, Michelle Bianchi de; Unesp; Toledo, Vivian Graziele Leite de; School of Dentistry – Institute of Science and Technology – UNESP – Univ Estadual Paulista – São José dos Campos – SP – Brazil.; Nascimento, Rodrigo Dias; Department of Diagnosis and Surgery – School of Dentistry – Institute of Science and Technology – UNESP – Univ Estadual Paulista – São José dos Campos – SP – Brazil.; Gonçalves, Fernanda de Cássia Papaiz; Department of Dental Materials and Prosthodontics – School of Dentistry – Institute of Science and Technology – UNESP – Univ Estadual Paulista – São José dos Campos – SP – Brazil.; Raldi, Fernando Vagner; Department of Diagnosis and Surgery – School of Dentistry – Institute of Science and Technology – UNESP – Univ Estadual Paulista – São José dos Campos – SP – Brazil.

    2015-01-01

    Objective: With the scientific and technological advances, the life expectancy of the population has increased over the years. With the advent of dental implants, a new possibility of treatment for oral rehabilitation was created to help or even help overcome the limits of conventional fixed dentures, removable and mainly total. Compared to conventional rehabilitation treatment on natural teeth, rehabilitation on implants has higher rates of success and longevity. Material and Methods: For th...

  7. Postoperative irradiation after implant placement: A pilot study for prosthetic reconstruction

    Science.gov (United States)

    Keum, Ki Chang; Kim, Jun Won; Shim, June-Sung; Jung, Han-Sung; Park, Kyeong-Mee

    2016-01-01

    PURPOSE On maxillofacial tumor patients, oral implant placement prior to postoperative radiotherapy can shorten the period of prosthetic reconstruction. There is still lack of research on effects of post-implant radiotherapy such as healing process or loading time, which is important for prosthodontic treatment planning. Therefore, this study evaluated the effects of post-implant local irradiation on the osseointegration of implants during different healing stages. MATERIALS AND METHODS Custom-made implants were placed bilaterally on maxillary posterior edentulous area 4 weeks after extraction of the maxillary first molars in Forty-eight Sprague-Dawley rats. Experimental group (exp.) received radiation after implant surgery and the other group (control) didn't. Each group was divided into three sub-groups according to the healing time (2, 4, and 8 week) from implant placement. The exp. group 1, 2 received 15-Gy radiation 1 day after implant placement (immediate irradiation). The exp. group 3 received 15-Gy radiation 4 weeks after implant placement (delayed irradiation). RESULTS The bone mineral density (BMD) was significantly lower in the immediate irradiation groups. BMD was similar in the delayed irradiation group and the control group. The irradiated groups exhibited a lower bone-to-implant contact ratio, although the difference was not statistically significant. The irradiated groups also exhibited a significantly lower bone volume and higher empty lacuna count than the control groups. No implant failure due to local irradiation was found in this study. CONCLUSION Within the limits of this study, the timing of local irradiation critically influences the bone healing mechanism, which is related to loading time of prostheses. PMID:27826386

  8. Children with Cochlear Implants and Developmental Disabilities: A Language Skills Study with Developmentally Matched Hearing Peers

    Science.gov (United States)

    Meinzen-Derr, Jareen; Wiley, Susan; Grether, Sandra; Choo, Daniel I.

    2011-01-01

    The number of children receiving cochlear implants (CIs) with significant disabilities in addition to their deafness has increased substantially. Unfortunately, children with additional disabilities receiving CIs have largely been excluded from studies on cochlear implant outcomes. Thus limited data exists on outcomes in this population to guide…

  9. A feasibility study of magnetic resonance imaging of silicone breast implants in Finland

    DEFF Research Database (Denmark)

    Kulmala, Ilona; Boice, John D; McLaughlin, Joseph K

    2005-01-01

    Cosmetic breast implants have become increasingly popular throughout the world. However, there is insufficient knowledge about the frequency and severity of local complications such as rupture and capsular contracture. A pilot study of 25 Finnish women with 50 cosmetic breast implants was organized...

  10. Mandibular Overdentures Supported by 6-mm Dental Implants : A 1-Year Prospective Cohort Study

    NARCIS (Netherlands)

    Gulje, Felix; Raghoebar, Gerry M.; Ter Meulen, Jan-Willem P.; Vissink, Arjan; Meijer, Henny J. A.; Guljé, Felix

    Background: The extremely resorbed edentulous mandible, with a bone height of 8 mm or less, is still a challenge in implant dentistry. Recently, dental implants of 6 mm in length have been developed. Purpose: The purpose of this 1-year prospective cohort study was to evaluate treatment outcome of

  11. The Development of Falling Intonation in Young Children with Cochlear Implants: A 2-Year Longitudinal Study

    Science.gov (United States)

    Snow, David P.; Ertmer, David J.

    2013-01-01

    This article describes the development of intonation in 12 cochlear implant (CI) recipients. In a previously reported study of the first year of CI use, children who were implanted late (after 24 months) acquired intonation more rapidly than the younger participants. The older children's advantage is plausibly owing to their greater maturity.…

  12. Study of phonological awareness of preschool and school aged children with cochlear implant and normal hearing.

    Science.gov (United States)

    Rastegarianzadeh, Niloufar; Shahbodaghi, Mohammadrahim; Faghihzadeh, Soghrat

    2014-09-01

    The primary purpose of this study was to assess whether very early access to speech sounds provided by the cochlear implant enables children to develop age-appropriate phonological awareness abilities in their preschool and school years. A secondary purpose of this study was to examine whether children who had cochlear implantation before 18 months of age will develop better skills in phonological awareness than children who had cochlear implants in 18-36 months of age. A third purpose of this study was to examine whether some factors like the child's age or sex would have any effects on developing of age-appropriate phonological awareness abilities. 48 children with 70 to 95 months of age who had been utilizing their cochlear implant(s) before 36 months of age (CI group) and 30 normal hearing peers (NH group) were enrolled in this study. Child's age had a significant effect on phonological awareness, but sex had absolutely no effect in each group. Children in the cochlear implanted group were outperformed by their normal hearing peers in the area of phonological awareness, especially in phonemic awareness. The age of implantation was another significant variable. Although children with a younger age at implantation got better scores in phonological awareness test, they were outperformed by their normal hearing peers in this area.

  13. Mandibular Overdentures Supported by 6-mm Dental Implants : A 1-Year Prospective Cohort Study

    NARCIS (Netherlands)

    Gulje, Felix; Raghoebar, Gerry M.; Ter Meulen, Jan-Willem P.; Vissink, Arjan; Meijer, Henny J. A.; Guljé, Felix

    2012-01-01

    Background: The extremely resorbed edentulous mandible, with a bone height of 8 mm or less, is still a challenge in implant dentistry. Recently, dental implants of 6 mm in length have been developed. Purpose: The purpose of this 1-year prospective cohort study was to evaluate treatment outcome of ma

  14. One-Piece Zirconia Ceramic versus Titanium Implants in the Jaw and Femur of a Sheep Model: A Pilot Study

    Directory of Open Access Journals (Sweden)

    A. Siddiqi

    2016-01-01

    Full Text Available Reports have documented titanium (Ti hypersensitivity after dental implant treatment. Alternative materials have been suggested including zirconia (Zr ceramics, which have shown predictable osseointegration in animal studies and appear free of immune responses. The aim of the research was to investigate the bone-to-implant contact (BIC of one-piece Zr, compared with one-piece Ti implants, placed in the jaws and femurs of domestic sheep. Ten New Zealand mixed breed sheep were used. A One-piece prototype Ti (control and one Zr (test implant were placed in the mandible, and one of each implant (Ti and Zr was placed into the femoral epicondyle of each animal. The femur implants were submerged and unloaded; the mandibular implants were placed using a one-stage transgingival protocol and were nonsubmerged. After a healing period of 12 weeks, %BIC was measured. The overall survival rate for mandibular and femur implants combined was 87.5%. %BIC was higher for Zr implants versus Ti implants in the femur (85.5%, versus 78.9% (p=0.002. Zirconia implants in the mandible showed comparable %BIC to titanium implants (72.2%, versus 60.3% (p=0.087. High failure rate of both Zr and Ti one-piece implants in the jaw could be attributed to the one-piece design and surface characteristics of the implant that could have influenced osseointegration. Further clinical trials are recommended to evaluate the performance of zirconia implants under loading conditions.

  15. One-Piece Zirconia Ceramic versus Titanium Implants in the Jaw and Femur of a Sheep Model: A Pilot Study

    Science.gov (United States)

    De Silva, R. K.; Zafar, S.

    2016-01-01

    Reports have documented titanium (Ti) hypersensitivity after dental implant treatment. Alternative materials have been suggested including zirconia (Zr) ceramics, which have shown predictable osseointegration in animal studies and appear free of immune responses. The aim of the research was to investigate the bone-to-implant contact (BIC) of one-piece Zr, compared with one-piece Ti implants, placed in the jaws and femurs of domestic sheep. Ten New Zealand mixed breed sheep were used. A One-piece prototype Ti (control) and one Zr (test) implant were placed in the mandible, and one of each implant (Ti and Zr) was placed into the femoral epicondyle of each animal. The femur implants were submerged and unloaded; the mandibular implants were placed using a one-stage transgingival protocol and were nonsubmerged. After a healing period of 12 weeks, %BIC was measured. The overall survival rate for mandibular and femur implants combined was 87.5%. %BIC was higher for Zr implants versus Ti implants in the femur (85.5%, versus 78.9%) (p = 0.002). Zirconia implants in the mandible showed comparable %BIC to titanium implants (72.2%, versus 60.3%) (p = 0.087). High failure rate of both Zr and Ti one-piece implants in the jaw could be attributed to the one-piece design and surface characteristics of the implant that could have influenced osseointegration. Further clinical trials are recommended to evaluate the performance of zirconia implants under loading conditions. PMID:28058261

  16. Functionalized Antimicrobial Composite Thin Films Printing for Stainless Steel Implant Coatings.

    Science.gov (United States)

    Floroian, Laura; Ristoscu, Carmen; Mihailescu, Natalia; Negut, Irina; Badea, Mihaela; Ursutiu, Doru; Chifiriuc, Mariana Carmen; Urzica, Iuliana; Dyia, Hussien Mohammed; Bleotu, Coralia; Mihailescu, Ion N

    2016-06-09

    In this work we try to address the large interest existing nowadays in the better understanding of the interaction between microbial biofilms and metallic implants. Our aimed was to identify a new preventive strategy to control drug release, biofilm formation and contamination of medical devices with microbes. The transfer and printing of novel bioactive glass-polymer-antibiotic composites by Matrix-Assisted Pulsed Laser Evaporation into uniform thin films onto 316 L stainless steel substrates of the type used in implants are reported. The targets were prepared by freezing in liquid nitrogen mixtures containing polymer and antibiotic reinforced with bioglass powder. The cryogenic targets were submitted to multipulse evaporation by irradiation with an UV KrF* (λ = 248 nm, τFWHM ≤ 25 ns) excimer laser source. The prepared structures were analyzed by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and profilometry, before and after immersion in physiological fluids. The bioactivity and the release of the antibiotic have been evaluated. We showed that the incorporated antibiotic underwent a gradually dissolution in physiological fluids thus supporting a high local treatment efficiency. Electrochemical measurements including linear sweep voltammetry and impedance spectroscopy studies were carried out to investigate the corrosion resistance of the coatings in physiological environments. The in vitro biocompatibility assay using the MG63 mammalian cell line revealed that the obtained nanostructured composite films are non-cytotoxic. The antimicrobial effect of the coatings was tested against Staphylococcus aureus and Escherichia coli strains, usually present in implant-associated infections. An anti-biofilm activity was evidenced, stronger against E. coli than the S. aureus strain. The results proved that the applied method allows for the fabrication of implantable biomaterials which shield metal ion release and possess

  17. Functionalized Antimicrobial Composite Thin Films Printing for Stainless Steel Implant Coatings

    Directory of Open Access Journals (Sweden)

    Laura Floroian

    2016-06-01

    Full Text Available In this work we try to address the large interest existing nowadays in the better understanding of the interaction between microbial biofilms and metallic implants. Our aimed was to identify a new preventive strategy to control drug release, biofilm formation and contamination of medical devices with microbes. The transfer and printing of novel bioactive glass-polymer-antibiotic composites by Matrix-Assisted Pulsed Laser Evaporation into uniform thin films onto 316 L stainless steel substrates of the type used in implants are reported. The targets were prepared by freezing in liquid nitrogen mixtures containing polymer and antibiotic reinforced with bioglass powder. The cryogenic targets were submitted to multipulse evaporation by irradiation with an UV KrF* (λ = 248 nm, τFWHM ≤ 25 ns excimer laser source. The prepared structures were analyzed by infrared spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy and profilometry, before and after immersion in physiological fluids. The bioactivity and the release of the antibiotic have been evaluated. We showed that the incorporated antibiotic underwent a gradually dissolution in physiological fluids thus supporting a high local treatment efficiency. Electrochemical measurements including linear sweep voltammetry and impedance spectroscopy studies were carried out to investigate the corrosion resistance of the coatings in physiological environments. The in vitro biocompatibility assay using the MG63 mammalian cell line revealed that the obtained nanostructured composite films are non-cytotoxic. The antimicrobial effect of the coatings was tested against Staphylococcus aureus and Escherichia coli strains, usually present in implant-associated infections. An anti-biofilm activity was evidenced, stronger against E. coli than the S. aureus strain. The results proved that the applied method allows for the fabrication of implantable biomaterials which shield metal ion release

  18. Activin-Like Kinase 2 Functions in Peri-implantation Uterine Signaling in Mice and Humans

    Science.gov (United States)

    Clementi, Caterina; Tripurani, Swamy K.; Large, Michael J.; Edson, Mark A.; Creighton, Chad J.; Hawkins, Shannon M.; Kovanci, Ertug; Kaartinen, Vesa; Lydon, John P.; Pangas, Stephanie A.; DeMayo, Francesco J.; Matzuk, Martin M.

    2013-01-01

    Implantation of a blastocyst in the uterus is a multistep process tightly controlled by an intricate regulatory network of interconnected ovarian, uterine, and embryonic factors. Bone morphogenetic protein (BMP) ligands and receptors are expressed in the uterus of pregnant mice, and BMP2 has been shown to be a key regulator of implantation. In this study, we investigated the roles of the BMP type 1 receptor, activin-like kinase 2 (ALK2), during mouse pregnancy by producing mice carrying a conditional ablation of Alk2 in the uterus (Alk2 cKO mice). In the absence of ALK2, embryos demonstrate delayed invasion into the uterine epithelium and stroma, and upon implantation, stromal cells fail to undergo uterine decidualization, resulting in sterility. Mechanistically, microarray analysis revealed that CCAAT/enhancer-binding protein β (Cebpb) expression is suppressed during decidualization in Alk2 cKO females. These findings and the similar phenotypes of Cebpb cKO and Alk2 cKO mice lead to the hypothesis that BMPs act upstream of CEBPB in the stroma to regulate decidualization. To test this hypothesis, we knocked down ALK2 in human uterine stromal cells (hESC) and discovered that ablation of ALK2 alters hESC decidualization and suppresses CEBPB mRNA and protein levels. Chromatin immunoprecipitation (ChIP) analysis of decidualizing hESC confirmed that BMP signaling proteins, SMAD1/5, directly regulate expression of CEBPB by binding a distinct regulatory sequence in the 3′ UTR of this gene; CEBPB, in turn, regulates the expression of progesterone receptor (PGR). Our work clarifies the conserved mechanisms through which BMPs regulate peri-implantation in rodents and primates and, for the first time, uncovers a linear pathway of BMP signaling through ALK2 to regulate CEBPB and, subsequently, PGR during decidualization. PMID:24244176

  19. Surgical factors in pediatric cochlear implantation and their early effects on electrode activation and functional outcomes.

    Science.gov (United States)

    Francis, Howard W; Buchman, Craig A; Visaya, Jiovani M; Wang, Nae-Yuh; Zwolan, Teresa A; Fink, Nancy E; Niparko, John K

    2008-06-01

    To assess the impact of surgical factors on electrode status and early communication outcomes in young children in the first 2 years of cochlear implantation. Prospective multicenter cohort study. Six tertiary referral centers. Children 5 years or younger before implantation with normal nonverbal intelligence. Cochlear implant operations in 209 ears of 188 children. Percent active channels, auditory behavior as measured by the Infant Toddler Meaningful Auditory Integration Scale/Meaningful Auditory Integration Scale and Reynell receptive language scores. Stable insertion of the full electrode array was accomplished in 96.2% of ears. At least 75% of electrode channels were active in 88% of ears. Electrode deactivation had a significant negative effect on Infant Toddler Meaningful Auditory Integration Scale/Meaningful Auditory Integration Scale scores at 24 months but no effect on receptive language scores. Significantly fewer active electrodes were associated with a history of meningitis. Surgical complications requiring additional hospitalization and/or revision surgery occurred in 6.7% of patients but had no measurable effect on the development of auditory behavior within the first 2 years. Negative, although insignificant, associations were observed between the need for perioperative revision of the device and 1) the percent of active electrodes and 2) the receptive language level at 2-year follow-up. Activation of the entire electrode array is associated with better early auditory outcomes. Decrements in the number of active electrodes and lower gains of receptive language after manipulation of the newly implanted device were not statistically significant but may be clinically relevant, underscoring the importance of surgical technique and the effective placement of the electrode array.

  20. Activin-like kinase 2 functions in peri-implantation uterine signaling in mice and humans.

    Science.gov (United States)

    Clementi, Caterina; Tripurani, Swamy K; Large, Michael J; Edson, Mark A; Creighton, Chad J; Hawkins, Shannon M; Kovanci, Ertug; Kaartinen, Vesa; Lydon, John P; Pangas, Stephanie A; DeMayo, Francesco J; Matzuk, Martin M

    2013-11-01

    Implantation of a blastocyst in the uterus is a multistep process tightly controlled by an intricate regulatory network of interconnected ovarian, uterine, and embryonic factors. Bone morphogenetic protein (BMP) ligands and receptors are expressed in the uterus of pregnant mice, and BMP2 has been shown to be a key regulator of implantation. In this study, we investigated the roles of the BMP type 1 receptor, activin-like kinase 2 (ALK2), during mouse pregnancy by producing mice carrying a conditional ablation of Alk2 in the uterus (Alk2 cKO mice). In the absence of ALK2, embryos demonstrate delayed invasion into the uterine epithelium and stroma, and upon implantation, stromal cells fail to undergo uterine decidualization, resulting in sterility. Mechanistically, microarray analysis revealed that CCAAT/enhancer-binding protein β (Cebpb) expression is suppressed during decidualization in Alk2 cKO females. These findings and the similar phenotypes of Cebpb cKO and Alk2 cKO mice lead to the hypothesis that BMPs act upstream of CEBPB in the stroma to regulate decidualization. To test this hypothesis, we knocked down ALK2 in human uterine stromal cells (hESC) and discovered that ablation of ALK2 alters hESC decidualization and suppresses CEBPB mRNA and protein levels. Chromatin immunoprecipitation (ChIP) analysis of decidualizing hESC confirmed that BMP signaling proteins, SMAD1/5, directly regulate expression of CEBPB by binding a distinct regulatory sequence in the 3' UTR of this gene; CEBPB, in turn, regulates the expression of progesterone receptor (PGR). Our work clarifies the conserved mechanisms through which BMPs regulate peri-implantation in rodents and primates and, for the first time, uncovers a linear pathway of BMP signaling through ALK2 to regulate CEBPB and, subsequently, PGR during decidualization.

  1. Activin-like kinase 2 functions in peri-implantation uterine signaling in mice and humans.

    Directory of Open Access Journals (Sweden)

    Caterina Clementi

    2013-11-01

    Full Text Available Implantation of a blastocyst in the uterus is a multistep process tightly controlled by an intricate regulatory network of interconnected ovarian, uterine, and embryonic factors. Bone morphogenetic protein (BMP ligands and receptors are expressed in the uterus of pregnant mice, and BMP2 has been shown to be a key regulator of implantation. In this study, we investigated the roles of the BMP type 1 receptor, activin-like kinase 2 (ALK2, during mouse pregnancy by producing mice carrying a conditional ablation of Alk2 in the uterus (Alk2 cKO mice. In the absence of ALK2, embryos demonstrate delayed invasion into the uterine epithelium and stroma, and upon implantation, stromal cells fail to undergo uterine decidualization, resulting in sterility. Mechanistically, microarray analysis revealed that CCAAT/enhancer-binding protein β (Cebpb expression is suppressed during decidualization in Alk2 cKO females. These findings and the similar phenotypes of Cebpb cKO and Alk2 cKO mice lead to the hypothesis that BMPs act upstream of CEBPB in the stroma to regulate decidualization. To test this hypothesis, we knocked down ALK2 in human uterine stromal cells (hESC and discovered that ablation of ALK2 alters hESC decidualization and suppresses CEBPB mRNA and protein levels. Chromatin immunoprecipitation (ChIP analysis of decidualizing hESC confirmed that BMP signaling proteins, SMAD1/5, directly regulate expression of CEBPB by binding a distinct regulatory sequence in the 3' UTR of this gene; CEBPB, in turn, regulates the expression of progesterone receptor (PGR. Our work clarifies the conserved mechanisms through which BMPs regulate peri-implantation in rodents and primates and, for the first time, uncovers a linear pathway of BMP signaling through ALK2 to regulate CEBPB and, subsequently, PGR during decidualization.

  2. Changes in Crestal Bone Around Endosseous Implants During Functional Loading: A Radiographic Evaluation in Edentulous Patients Comparing Different Implant Designs

    OpenAIRE

    Tymstra, N.; Meijer, H.J.A.; Raghoebar, G.M.; Vissink, A

    2012-01-01

    Marginal bone changes around titanium plasma-sprayed implants (n = 240) placed in the mandibular interforaminal regions of 120 edentulous patients were assessed over 5 years of follow-up, with emphasis on the influence of the locations of the microgap and rough/smooth border. Marginal bone changes were measured on standardized radiographs. Locations of the microgap and the rough/smooth border were both shown not to be major contributing factors in determining the marginal bone level around im...

  3. EX-PRESS® Implant Position and Function: Comparative Evaluation with Ultrasound Biomicroscopy and Optical Coherence Tomography

    Science.gov (United States)

    Detorakis, Efstathios T.; Stojanovic, Nela; Chalkia, Aikaterini; Pallikaris, Ioannis G.

    2016-01-01

    Purpose: This study evaluated the feasibility of anterior segment optical coherence tomography (OCT) and ultrasound biomicroscopy (UBM) for the imaging of EX-PRESS® implant. Materials and Methods: This nonrandomized comparative case series was performed at the Department of Ophthalmology of the University Hospital of Heraklion, Crete, Greece. The Ellex Eye Cubed (40 MHz) UBM and the Zeiss Visante OCT systems were used. The filtering bleb morphology (BL), aqueous outflow (AS), and tube position (TB) were evaluated by two independent observers using a quality scale of 1 (worst) to 4 (best). Data were also collected on corneal and iris clearance from the tip of the tube (CC and IC, respectively). Data from both the devices were statistically analyzed. P 0.05). Conclusion: Imaging of the EX-PRESS® implant is feasible with both UBM and OCT. Both modalities allow visualization of the position of the implant tube in relation to the iris or cornea and delineate the internal structure of the filtering bleb. PMID:26957849

  4. Relationship between right and left ventricular function in candidates for implantable cardioverter defibrillator with low left ventricular ejection fraction.

    Science.gov (United States)

    Jimenez-Juan, Laura; Karur, Gauri R; Connelly, Kim A; Deva, Djeven; Yan, Raymond T; Wald, Rachel M; Singh, Sheldon; Leung, General; Oikonomou, Anastasia; Dorian, Paul; Angaran, Paul; Yan, Andrew T

    2017-04-01

    Indications for the primary prevention of sudden death using an implantable cardioverter defibrillator (ICD) are based predominantly on left ventricular ejection fraction (LVEF). However, right ventricular ejection fraction (RVEF) is also a known prognostic factor in a variety of structural heart diseases that predispose to sudden cardiac death. We sought to investigate the relationship between right and left ventricular parameters (function and volume) measured by cardiovascular magnetic resonance (CMR) among a broad spectrum of patients considered for an ICD. In this retrospective, single tertiary-care center study, consecutive patients considered for ICD implantation who were referred for LVEF assessment by CMR were included. Right and left ventricular function and volumes were measured. In total, 102 patients (age 62±14 years; 23% women) had a mean LVEF of 28±11% and RVEF of 44±12%. The left ventricular and right ventricular end diastolic volume index was 140±42 mL/m(2) and 81±27 mL/m(2), respectively. Eighty-six (84%) patients had a LVEF right ventricular systolic dysfunction. Although there was a significant and moderate correlation between LVEF and RVEF (r=0.40, pright ventricular systolic dysfunction (Kappa=0.041). Among patients being considered for an ICD, there is a positive but moderate correlation between LVEF and RVEF. A considerable proportion of patients who qualify for an ICD based on low LVEF have preserved RVEF, and vice versa.

  5. Patient's opinion and treatment outcome of fixed rehabilitation on Brånemark implants. A 3-year follow-up study in private dental practices.

    Science.gov (United States)

    de Bruyn, H; Collaert, B; Lindén, U; Björn, A L

    1997-08-01

    In this study, patient opinion on oral rehabilitation by means of Brånemark implants was investigated. All patients were referred to a periodontal clinic for implant installation and treated by one and the same operator. Prosthetic restorations were performed by dentists, who had no previous experience with prostheses on implants, but had completed a postgraduate training course. Patient opinion was obtained through questionnaires, pertaining to satisfaction and oral function. A comparison was made between pre-implant situation, short-term (implant-restorative rehabilitation. In total, 61 patients participated in the study; 23 received a full lower arch bridge and 18 a full upper arch bridge, while 20 patients got partial bridges. Of 298 installed implants, 7 failed at abutment connection (2.3%) and 1 during the 3-year follow-up interval (0.3%). The study results indicated that a great majority of patients were very satisfied with the treatment. Comfort with eating, aesthetics, phonetics and overall satisfaction improved significantly and nearly all patients said that they would undergo the treatment again or recommend it to others. Patients experienced their implants as "natural" teeth. The conclusion is that rehabilitation ad modum Brånemark, even in the hands of non-specialized dentists, can be of high quality, improving oral function and satisfying the needs and demands of patients.

  6. Experimental acrylonitrile butadiene styrene and polyamide evisceration implant: a rabbit clinical and histopathology study

    Directory of Open Access Journals (Sweden)

    D.C. Gomes Júnior

    Full Text Available ABSTRACT The purpose of this study was to evaluate acrylonitrile butadiene styrene (ABS and polyamide implants in rabbits submitted to evisceration at the macroscopic and microstructure level and to assess clinical response and histopathological changes as well. For the experimental study implants of 12mm diameter were prepared by rapid prototyping, weighed and the outer and inner surfaces evaluated macroscopically and by electron microscopy. In addition, a compression test was performed and ultrastructural damage was then determined. After evisceration of the left eyeball, nine New Zealand rabbits received ABS implants and nine others received polyamide implants. The animals were assessed daily for 15 days after surgery and every seven days until the end of the study (90 days. Histopathological evaluation was performed at 15, 45 and 90 days after surgery. The ABS implants weighed approximately 0.44g, while the polyamide ones weighed 0.61g. Scanning electron microscopy demonstrated that the ABS implants had regular-sized, equidistant micropores, while the polyamide ones showed micropores of various sizes. The force required to fracture the ABS implant was 14.39 ±0.60 Mpa, while for the polyamide one, it was 16.80 ±1.05 Mpa. Fifteen days after surgery, we observed centripetal tissue infiltration and scarce inflammatory infiltrate. Implants may be used in the filling of anophthalmic cavities, because they are inert, biocompatible and allow tissue integration.

  7. Periodontal parameters of osseointegrated dental implants. A 4-year controlled follow-up study.

    Science.gov (United States)

    Nishimura, K; Itoh, T; Takaki, K; Hosokawa, R; Naito, T; Yokota, M

    1997-08-01

    The aim of this study was to evaluate the periodontal parameters of osseointegrated dental implants. The condition of the peri-implant mucosa was assessed using periodontal parameters, i.e., of plaque index, bleeding on probing, probing pocket depth, probing attachment level and Periotest scores as well as a radiographic parameter, over a 4-year follow-up period. 32 non-submerged ITI dental implants, all placed in the mandible, were studied in 12 patients who had good oral hygiene. All patients were regularly recalled at 6-month intervals. The overall implant success rate was 100%. None of the implants showed any signs of inflammation, radiographic bone loss or any detectable mobility during the follow-up period. Methods similar to those used to evaluate the natural dentition were effectively employed to assess the clinical status of the dental implants. The diagnostic value of these parameters could not, however, be determined from this study due to the absence of any peri-implant tissue complications. The results indicated that some periodontal parameters of healthy peri-implant mucosa might be slightly different from healthy periodontal tissue.

  8. Study of corrosion between a titanium implant and dental alloys.

    Science.gov (United States)

    Reclaru, L; Meyer, J M

    1994-06-01

    The infiltration of saliva into the multi-metallic structures on titanium implants brings different types of alloys into temporary or permanent contact. In this way a galvanic cell is established as a result of their potential difference. The galvanic cell phenomenon is compounded by another type of corrosion resulting from the geometry of the assembly: localized crevice corrosion. Fifteen galvanic couples (Ti/gold-based alloys, Ti/palladium-based alloy and Ti/non-precious alloys) were studied. Various electrochemical parameters (Ecorr, Ecommon, Ecouple corr, Ecrevice, icorr, icouple corr and Tafel slopes) were analysed. The galvanic currents measured are of the same order of magnitude (except Ti/stainless steel). They remain low. Application of the mixed-potential theory shows that titanium in coupling with the alloys studied will be under either cathodic or anodic control. According to the results obtained, an alloy that is potentially usable for superstructures in a galvanic coupling with titanium must fulfil a certain number of parameters: in a coupling, titanium must have a weak anodic polarization; the current generated by the galvanic cell must also be weak; the crevice potential must be markedly higher than the common potential.

  9. Performance of functionally graded implants of polylactides and calcium phosphate/calcium carbonate in an ovine model for computer assisted craniectomy and cranioplasty.

    Science.gov (United States)

    Eufinger, Harald; Rasche, Christian; Lehmbrock, Jutta; Wehmöller, Michael; Weihe, Stephan; Schmitz, Inge; Schiller, Carsten; Epple, Matthias

    2007-01-01

    Biodegradable functionally graded skull implants on the basis of polylactides and calcium phosphate/calcium carbonate were prepared in an individual mould using a combination of different processing techniques. A geometrically corresponding resection template was designed to enable a craniectomy and cranioplasty with the prepared implant in the same operation. After various preliminary experiments concerning degradation kinetics, pH evolution during degradation, micromorphology, biocompatibility tests in human osteoblast cell cultures and surgery of cadaver heads, a new large-animal model was developed for long-term in vivo studies. In eight 12-months-old sheep, the surgical templates were used to create 4.5 x 5 cm(2) calvarial defects which were then filled with the corresponding degradable implants in the same operation. The animals were sacrificed after 2, 9, 12 and 18 months, and the implants and the surrounding tissues were analysed by computer tomography (CT), macroscopic examination and microscopy. The new animal model proved to be reliable and very suitable for large individual craniectomies and cranioplasties. The formation of new bone from the dural layer of the meninges corresponded well to the degradation of the porous inner layer of the implants whereas the skull contour was stabilised by the compact outer layer over the follow-up period.

  10. 非球面人工晶状体Acri Smart 36A-5植入术后视功能评价%A clinical study of visual function after Acri Smart 36A-5 intraocular lens Implantation

    Institute of Scientific and Technical Information of China (English)

    赵珂珂; 赵云娥; 汪朝阳; 王勤美

    2009-01-01

    Objective To investigate the visual function after implantation of Acri Smart 36A-5 aspheric intraocular lens(IOL)in patients with age-related cataract.Methods We continuous selected 112 eyes of 90 age-related cataract patients requiring cataract surgery from Jun.2005 to Aug.2006 in our hospital.The patients were randomized to receive one of these three IOL typesd: Acri Smart 36A-5IOL(as group A,37 eyes),Teenis Z9001 IOL(as group B,39 eyes)or AR40e IOL(as group C,36 eyes).After 3 months,measure of refraction and best spectacle corrected visual acuity(BCVA),and contrast sensitivity with or without glare(CSV-1000)were examined.Results(1)There were not significantly different among 3 groups in BCVA in 3-month postoperatively(P=0.473).(2)Without glare(0.61ux),in the 6c/d,12c/d and 18c/d frequencies,there were significantly higher spatial contrast sensitivity in group A and group B than group C.With glare(151ux),in 6c/d,18c/d,there were statistically significant differences between group A or group B and group C.With glare(851ux),in 18c/d,there were statistically significant differences between group A or group B and group C.There were not significantly difference between group A and group B in any glare condition.Conclusion(1)Aspheric IOLs Acri Smart 36A-5 can increase the contrast sensitivity of some frequencies with or without glare after cataract surgery.(2)There is no difference between these two Aspheric IOLs in visual function.%目的 评价非球面人工晶状体Acri Smart 36A-5对提高年龄相关性白内障患者术后视功能的作用.方法 根据入选标准连续收集年龄相关性白内障患者90例(112只眼),随机分为三组,A组植入Acri Smart 36A-5为30例(37只眼),B组植入Tecnis Z9001为31例(39只眼)及C组AR 40e为29例(36只眼).术后3月检查术眼屈光度及最佳矫正视力(BCVA)、无眩光及眩光环境下对比敏感度.结果 (1)BCVA:组间无统计学意义(P=0.473).(2)对比敏感度:在无眩光环境下,6e/d、12c

  11. Bacteriophage therapy in implant-related infections: an experimental study.

    Science.gov (United States)

    Yilmaz, Cengiz; Colak, Mehmet; Yilmaz, Banu Coskun; Ersoz, Gulden; Kutateladze, Mzia; Gozlugol, Mehmet

    2013-01-16

    Implant-related infections with bacteria resistant to multiple antibiotics represent one of the major problems in orthopaedic surgery. It was our hypothesis that local application of bacteriophages, which are bacteria-destroying viruses, would be effective against biofilm-forming bacteria. An implant-related infection model was created using methicillin-resistant Staphylococcus aureus (MRSA) in forty-eight rats and Pseudomonas aeruginosa in another forty-eight rats. Each group was divided into four subgroups; one subgroup received a bacterium-specific bacteriophage (Sb-1 in the MRSA group and PAT14 in the Pseudomonas aeruginosa group), one received antibiotic for fourteen days (20 mg/kg/day teicoplanin in the MRSA group, and 120 mg/kg/day imipenem + cilastatin and 25 mg/kg/day amikacin in the Pseudomonas group), one received antibiotic and bacteriophage, and one received no treatment. Animals receiving bacteriophage therapy were injected locally with 107 bacteriophages in a 0.1-mL suspension on three consecutive days. All animals were killed on the fifteenth day after initiation of treatment, and the tibia was excised. Results were assessed with use of microbiology, light microscopy, and electron microscopy. In the MRSA group, the antibiotic administration significantly decreased the number of colony-forming units per subject in quantitative cultures (control subgroup, 50,586; bacteriophage, 30,788; antibiotic, 17,165; antibiotic + bacteriophage, 5000; p = 0.004 for the comparison of the latter group with the control). Biofilm was absent only in the antibiotic + bacteriophage subgroup. In the Pseudomonas group, the number of colony-forming units per subject in quantitative cultures was significantly lower in each treatment subgroup compared with the control subgroup (control subgroup, 14,749; bacteriophage, 6484 [p = 0.016]; antibiotic, 2619 [p = 0.01]; antibiotic + bacteriophage, 1705 [p bacteriophage subgroup was also significantly lower than the values in the

  12. Conventional versus implant-retained overlay dentures: a pilot study of masseter and anterior temporalis electromyography.

    Science.gov (United States)

    Dakhilalian, Mansour; Rismanchian, Mansour; Fazel, Akbar; Basiri, Keyvan; Azadeh, Hamid; Mahmoodi, Maryam; Fayazi, Sara; Sadr-Eshkvari, Pooyan

    2014-08-01

    Implant-supported overlay dentures (ISODs) have been widely accepted among patients using conventional removable complete dentures (CRCDs). The present study aimed to comparatively study conventional and ISODs in terms of function and coordination of masticatory muscles using electromyograms. Included were 10 patients with ISODs (each with 2 implants in the intercanine area). The mean wave range (MWR) and frequency (MWF) of masseter and temporalis were recorded with (ISOD) and without (CRCD) ball attachments while maximum clenching on cotton rolls (cotton roll clenching), maximum intercuspal clenching (clenching), and unilateral gum chewing (chewing) using electromyography. Data were analyzed in SPAW using t-paired for matched groups and independent-sample t tests for unmatched ones. The MWF differences were not statistically significant with or without attachments (P > .05). Without attachments in place, the MWF of both masseter and temporalis muscles significantly decreased when patients clenched on cotton rolls (P = .01 and .02, respectively) and when chewing unilaterally (both P = .01). With attachments present, the right and left temporalis muscles did not show identical mean wave ranges while chewing (P = .01). Without attachments, this disharmony was seen in the left and right masseter muscles (P = .03). The MWR of masseter was higher in men while chewing with attachments (P = .02). Without attachments, the MWR of temporalis was higher in women while cotton roll clenching (P = .03) and chewing (P = .02). These findings are seemingly in favor of improved masticatory function and coordination in edentulous patients with the application of ISODs.

  13. A Prospective Longitudinal Study of U.S. Children Unable to Achieve Open-Set Speech Recognition 5 Years After Cochlear Implantation.

    Science.gov (United States)

    Barnard, Jennifer M; Fisher, Laurel M; Johnson, Karen C; Eisenberg, Laurie S; Wang, Nae-Yuh; Quittner, Alexandra L; Carson, Christine M; Niparko, John K

    2015-07-01

    To identify characteristics associated with the inability to progress to open-set speech recognition in children 5 years after cochlear implantation. Prospective, longitudinal, and multidimensional assessment of auditory development for 5 years. Six tertiary cochlear implant (CI) referral centers in the United States. Children with severe-to-profound hearing loss who underwent implantation before age 5 years enrolled in the Childhood Development after Cochlear Implantation study, categorized by level of speech recognition ability. Cochlear implantation before 5 years of age and annual assessment of emergent speech recognition skills. Progression to open-set speech recognition by 5 years after implantation. Less functional hearing before implantation, older age at onset of amplification, lower maternal sensitivity to communication needs, minority status, and complicated perinatal history were associated with the inability to obtain open-set speech recognition by 5 years. Characteristics of a subpopulation of children with CIs associated with an inability to achieve open-set speech recognition after 5 years of CI experience were investigated. These data distinguish pediatric CI recipients at risk for poor auditory development and highlight areas for future interventions to enhance support of early implantation.

  14. Titanium implant impairment and surrounding muscle cell death following neuro-myoelectrostimulation: An in vivo study.

    Science.gov (United States)

    Lecocq, Mathieu; Félix, Marie-Solenne; Linares, Jean-Marc; Chaves-Jacob, Julien; Decherchi, Patrick; Dousset, Erick

    2015-11-01

    Electrical currents have deleterious effects on biomedical metallic implants. However, following arthroplasty, neuro-myoelectrostimulation (NMES) is often used in patient rehabilitation. Such a rehabilitation technique could compromise patient recovery through deleterious effects on metallic alloys and biological tissues. The purpose of our study was to assess the effects of NMES on a Ti6Al4V implant placed in a rat tibial crest and the surrounding muscle tissues. This in vivo study allowed to bring to the fore the prosthesis behavior under mechanical and electromagnetic loads induced by NEMS stimulation. After 3 weeks, implant-to-bone adhesion significantly decreased in stimulated animals compared with nonstimulated animals. Surface mapping indicated titanium implant degradation after NMES. Furthermore, NMES alone did not induce muscle damage contrary to that found in implanted animals. The muscle damage rate was significantly higher in implanted and stimulated animals compared with implanted-only animals. It seems obvious that rehabilitation programs using the NMES technique could induce early deterioration of biomaterial employed for surgical implants. Clinicians should reconsider the use of NMES as a rehabilitation technique for patients with titanium prostheses.

  15. Early loading of implants with fixed dental prostheses in edentulous mandibles: 7.2-year clinical results from a prospective study.

    Science.gov (United States)

    Schwarz, Stefanie; Bernhart, Gunda; Eiffler, Constantin; Hassel, Alexander Jochen; Lehmann, Franziska; Rammelsberg, Peter

    2014-12-01

    The purpose of this prospective follow-up study was to evaluate survival and success of early-loaded implants placed in the edentulous mandible and the survival of the fixed dental prostheses (FDPs) after in mean 7.2 years. Thirty-seven patients (mean age 64.5 years, 18.9% male) received 185 implants in the intraforaminal area of the edentulous mandible (five implants per patient). Within 2 weeks, all implants were early loaded with fixed dental prostheses. The patients were recalled once a year for clinical and radiographic examinations. The 17 patients (79 implants) attending the recall in 2012 were additionally asked for their satisfaction of functional and aesthetic aspects. During a mean observation time of 7.2 years, 20 implants were lost in 11 patients, resulting in implant survival of 89.2%. Eight of all implants (4.3%) had too much marginal bone loss to satisfy the criteria of success. A total of 19 prosthetic complications and aftercare measurements had to be performed between in mean 4.5 to 7.2 years of observation. The survival of the original FDPs decreased to 83.8%. Of the 17 patients attending the recall in 2012, a total 59.5% had a satisfactory oral hygiene. According to the criteria of Albrektsson, the success rate for the remaining 79 implants was 89.9% after in mean 11.7 years. Patient satisfaction for assessment of functional and aesthetic aspects was in median 9 and 8 on the numeric rating scales. Long-term observation of in mean 7.2 years showed satisfactory results for both implant and superstructure survival. Prosthetic complications were easy to repair in most cases, but patients' ability for oral hygiene was reduced after the longer observation period. Especially in elderly patients, their attitudes and manual skills should be considered when planning the design of a new superstructure. © 2013 Wiley Periodicals, Inc.

  16. Clinical, microbiological, and immunological aspects of healthy versus peri-implantitis tissue in full arch reconstruction patients: a prospective cross-sectional study

    OpenAIRE

    Ata-Ali, Javier; Flichy-Fernández, Antonio Juan; Alegre-Domingo, Teresa; Ata-Ali, Fadi; Palacio, Jose; Peñarrocha-Diago, Miguel

    2015-01-01

    Background Due to the world-wide increase in treatments involving implant placement, the incidence of peri-implant disease is increasing. Late implant failure is the result of the inability to maintain osseointegration, whose most important cause is peri-implantitis. The aim of this study was to analyze the clinical, microbiological, and immunological aspects in the peri-implant sulcus fluid (PISF) of patients with healthy dental implants and patients with peri-implantitis. Methods PISF sampl...

  17. A STUDY OF EFFICACY AND SAFETY PROFILE WITH SUB DERMAL SINGLE ROD CONTRACEPTIVE IMPLANT IMPLANON

    Directory of Open Access Journals (Sweden)

    Sapna

    2015-03-01

    Full Text Available INTRODUCTION: The development of sub dermal contraceptive implant has been an important improvement in current contraceptive technology and to a good alternative to offer well established contraceptive method. Hormonal implant must show high efficacy, high acceptabilit y and rapid return of fertility after removal by maintaining a sustained release of progesterone, the contraceptive effect of the implant can be obtained with a much smaller daily dose than when administering the same steroid by an oral or intramuscular ro ute. Sub dermal implant s are also independent of user compliance which remains a determinant factor in the efficacy of most contraceptive methods. In addition after removal of the hormonal implant, fertility returns almost immediately. They contain only pr ogestogen, these implant may also be used by women who cannot tolerate oestrogen or by women for whom oestrogen is contraindicated. The availability of new innovative contraceptive implant system such as implanon is very important to offer couples alternat ive methods to plan size of their family more efficiently. OBJECTIVES: To study efficacy and safety profile of single rod sub dermal contraceptive device implant implanon. To evaluate the vaginal bleeding patterns observed during the use of implanon. To as sess the acceptability of the contraceptive device as indicated by discontinuation rates. MATERIAL AND METHODS: S tudy was carried in OBG department of RMC Kanpur on healthy female volunteers having regular menstruation & at least one living child. RESULT: The result of this study was excellent in terms of contraception with pearl index of 0, almost one third cases were having in frequent bleeding episode. CONCLUSION: The study was conducted on 110 women of age 20 - 35 years with at least one living child and having regular menstrual period, in present study half of cases discontinued implant due to no fix pattern of bleeding and failure was o%, efficacy of this implant

  18. Prevention of Cutaneous Tissue Contracture During Removal of Craniofacial Implant Superstructures for CT and MRI Studies

    Directory of Open Access Journals (Sweden)

    Maureen Sullivan

    2010-04-01

    Full Text Available Objectives: Head and neck cancer patients who have lost facial parts following surgical intervention frequently require craniofacial implant retained facial prostheses for restoration. Many craniofacial implant patients require computed tomography and magnetic resonance imaging scans as part of their long-term follow-up care. Consequently removal of implant superstructures and peri-abutment tissue management is required for those studies. The purpose of the present paper was to describe a method for eliminating cranial imaging artifacts in patients with craniofacial implants.Material and Methods: Three patients wearing extraoral implant retained facial prostheses needing either computed tomography or magnetic resonance imaging studies were discussed. Peri-implant soft tissues contracture after removal of percutaneous craniofacial implant abutments during computed tomography and magnetic resonance imaging studies was prevented using a method proposed by authors. The procedure involves temporary removal of the supra-implant components prior to imaging and filling of the tissue openings with polyvinyl siloxane dental impression material.Results: Immediately after filling of the tissue openings with polyvinyl siloxane dental impression material patients were sent for the imaging studies, and were asked to return for removal of the silicone plugs and reconnection of all superstructure hardware after imaging procedures were complete. The silicone plugs were easily removed with a dental explorer. The percutaneous abutments were immediately replaced and screwed into the implants which were at the bone level.Conclusions: Presented herein method eliminates the source of artifacts and prevents contracture of percutaneous tissues upon removal of the implant abutments during imaging.

  19. High temperature annealing studies of strontium ion implanted glassy carbon

    Energy Technology Data Exchange (ETDEWEB)

    Odutemowo, O.S., E-mail: u12052613@tuks.co.za [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Malherbe, J.B.; Prinsloo, L.; Langa, D.F. [Department of Physics, University of Pretoria, Pretoria 0002 (South Africa); Wendler, E. [Institut für Festkörperphysik, Friedrich-Schiller University, Jena (Germany)

    2016-03-15

    Glassy carbon samples were implanted with 200 keV strontium ions to a fluence of 2 × 10{sup 16} ions/cm{sup 2} at room temperature. Analysis with Raman spectroscopy showed that ion bombardment amorphises the glassy carbon structure. Partial recovery of the glassy carbon structure was achieved after the implanted sample was vacuum annealed at 900 °C for 1 h. Annealing the strontium ion bombarded sample at 2000 °C for 5 h resulted in recovery of the glassy carbon substrate with the intensity of the D peak becoming lower than that of the pristine glassy carbon. Rutherford backscattering spectroscopy (RBS) showed that the implanted strontium diffused towards the surface of the glassy carbon after annealing the sample at 900 °C. This diffusion was also accompanied by loss of the implanted strontium. Comparison between the as-implanted and 900 °C depth profiles showed that less than 30% of the strontium was retained in the glassy carbon after heat treatment at 900 °C. The RBS profile after annealing at 2000 °C indicated that no strontium ions were retained after heat treatment at this temperature.

  20. High temperature annealing studies of strontium ion implanted glassy carbon

    Science.gov (United States)

    Odutemowo, O. S.; Malherbe, J. B.; Prinsloo, L.; Langa, D. F.; Wendler, E.

    2016-03-01

    Glassy carbon samples were implanted with 200 keV strontium ions to a fluence of 2 × 1016 ions/cm2 at room temperature. Analysis with Raman spectroscopy showed that ion bombardment amorphises the glassy carbon structure. Partial recovery of the glassy carbon structure was achieved after the implanted sample was vacuum annealed at 900 °C for 1 h. Annealing the strontium ion bombarded sample at 2000 °C for 5 h resulted in recovery of the glassy carbon substrate with the intensity of the D peak becoming lower than that of the pristine glassy carbon. Rutherford backscattering spectroscopy (RBS) showed that the implanted strontium diffused towards the surface of the glassy carbon after annealing the sample at 900 °C. This diffusion was also accompanied by loss of the implanted strontium. Comparison between the as-implanted and 900 °C depth profiles showed that less than 30% of the strontium was retained in the glassy carbon after heat treatment at 900 °C. The RBS profile after annealing at 2000 °C indicated that no strontium ions were retained after heat treatment at this temperature.

  1. An implantable intracardiac accelerometer for monitoring myocardial contractility. The Multicenter PEA Study Group.

    Science.gov (United States)

    Rickards, A F; Bombardini, T; Corbucci, G; Plicchi, G

    1996-12-01

    As the myocardium contracts isometrically, it generates vibrations that are transmitted throughout the heart. These vibrations can be measured with an implantable microaccelerometer located inside the tip of an otherwise conventional unipolar pacing lead. These vibrations are, in their audible component, responsible for the first heart sound. The aim of this study was to evaluate, in man, the clinical feasibility and reliability of intracavity sampling of Peak Endocardial Acceleration (PEA) of the first heart sound vibrations using an implantable tip mounted accelerometer. We used a unidirectional accelerometer located inside the stimulating tip of a standard unipolar pacing lead: the sensor has a frequency response of DC to 1 kHz and a sensitivity of 5 mV/G (G = 9.81 m/s-2). The lead was connected to an external signal amplifier with a frequency range of 0.05-1,000 Hz and to a peak-to-peak detector synchronized with the endocardial R wave scanning the isovolumetric contraction phase. Following standard electrophysiological studies, sensor equipped leads were temporarily inserted in the RV of 15 patients (68 +/- 15 years), with normal regional and global ventricular function, to record PEA at rest, during AAI pacing, during VVI pacing, and during dobutamine infusion (up to 20 micrograms/kg per min). PEA at baseline was 1.1 G +/- 0.5 (heart rate = 75 +/- 14 beats/min) and increased to 1.3 G +/- 0.9 (P = NS vs baseline) during AAI pacing (heart rate = 140 beats/min) and to 1.4 G +/- 0.5 (P = NS vs baseline) during VVI pacing (heart rate = 140 beats/min). Dobutamine infusion increased PEA to 3.7 G +/- 1.1 (P < 0.001 vs baseline), with a heart rate of 121 +/- 13 beats/min. In a subset of three patients, simultaneous hemodynamic RV monitoring was performed to obtain RV dP/dtmax, whose changes during dobutamine and pacing were linearly related to changes in PEA (r = 0.9; P < 0.001). In conclusion, the PEA recording can be consistently and safely obtained with an

  2. Influence of direct laser fabrication implant topography on type IV bone: a histomorphometric study in humans.

    Science.gov (United States)

    Shibli, Jamil Awad; Mangano, Carlo; D'avila, Susana; Piattelli, Adriano; Pecora, Gabriele E; Mangano, Francesco; Onuma, Tatiana; Cardoso, Luciana A; Ferrari, Daniel Sanchez; Aguiar, Kelly C; Iezzi, Giovanna

    2010-05-01

    The aim of this histologic study was to evaluate the influence of the direct laser fabrication (DFL) surface topography on bone-to-implant contact (BIC%), on bone density in the threaded area (BA%) as well as bone density outside the threaded area (BD%) in type IV bone after 8 weeks of unloaded healing. Thirty patients (mean age 51.34 +/- 3.06 years) received 1 micro-implant (2.5-mm diameter and 6-mm length) each during conventional implant surgery in the posterior maxilla. Thirty micro-implants with three topographies were evaluated: 10 machined (cpTi); 10 sandblasted and acid etched surface (SAE) and 10 DFL micro-implants. After 8 weeks, the micro-implants and the surrounding tissue were removed and prepared for histomorphometric analysis. Four micro-implants (2 cpTi, 1 SAE and 1DLF) showed no osseointegration after the healing period. Histometric evaluation indicated that the mean BIC% was higher for the DFL and SAE surfaces (p = 0.0002). The BA% was higher for the DFL surface, although there was no difference with the SAE surface. The BD% was similar for all topographies (p > 0.05). Data suggest that the DFL and SAE surfaces presented a higher bone-to-implant contact rate compared with cpTi surfaces under unloaded conditions, after a healing period of 8 weeks.

  3. Influence of occlusal loading on peri-implant clinical parameters. A pilot study.

    Science.gov (United States)

    Pellicer-Chover, Hilario; Viña-Almunia, José; Romero-Millán, Javier; Peñarrocha-Oltra, David; García-Mira, Berta; Peñarrocha-Diago, María

    2014-05-01

    To investigate the relation between occlusal loading and peri-implant clinical parameters (probing depth, bleeding on probing, gingival retraction, width of keratinized mucosa, and crevicular fluid volume) in patients with implant-supported complete fixed prostheses in both arches. This clinical study took place at the University of Valencia (Spain) dental clinic. It included patients attending the clinic for regular check-ups during at least 12 months after rehabilitation of both arches with implant-supported complete fixed ceramo-metallic prostheses. One study implant and one control implant were established for each patient using the T-Scan®III computerized system (Tesco, South Boston, USA). The maxillary implant closest to the point of maximum occlusal loading was taken as the study implant and the farthest (with least loading) as the control. Occlusal forces were registered with the T-Scan® III and then occlusal adjustment was performed to distribute occlusal forces correctly. Peri-implant clinical parameters were analyzed in both implants before and two and twelve months after occlusal adjustment. Before occlusal adjustment, study group implants presented a higher mean volume of crevicular fluid (51.3 ± 7.4 UP) than the control group (25.8 ± 5.5 UP), with statistically significant difference. Two months after occlusal adjustment, there were no significant differences between groups (24.6 ± 3.8 UP and 26 ± 4.5 UP respectively) (p=0.977). After twelve months, no significant differences were found between groups (24.4 ± 11.1 UP and 22.5 ± 8.9 UP respectively) (p=0.323). For the other clinical parameters, no significant differences were identified between study and control implants at any of the study times (p>0.05). Study group implants receiving higher occlusal loading presented significantly higher volumes of crevicular fluid than control implants. Crevicular fluid volumes were similar in both groups two and twelve months after occlusal adjustment.

  4. Bone response to machined and resorbable blast material titanium implants: an experimental study in rabbits.

    Science.gov (United States)

    Piattelli, Maurizio; Scarano, Antonio; Paolantonio, Michele; Iezzi, Giovanna; Petrone, Giovanna; Piattelli, Adriano

    2002-01-01

    The aim of the present study was a comparison of implants' responses to a machined surface and to a surface sandblasted with hydroxyapatite (HA) particles (resorbable blast material [RBM]). Threaded machined and RBM, grade 3, commercially pure, titanium, screw-shaped inplants were used in this study. Twenty-four New Zealand white mature male rabbits were used. The inplants were inserted into the articular femoral knee joint according to a previously described technique. Each rabbit received 2 inplants, 1 test (RBM) and 1 control (machined). A total of 48 implants (24 control and 24 test) were inserted. The rabbits were anesthetized with intramuscular injections of fluanisone (0.7 mg/ kg body weight) and diazepam (1.5 mg/kg b.wt.), and local anesthesia was given using 1 mL of 2% lidocaine/adrenalin solution. Two rabbits died in the postoperative course. Four animals were euthanatized with an overdose of intravenous pentobarbital after 1, 2, 3, and 4 weeks; 6 rabbits were euthanatized after 8 weeks. A total of 44 implants were retrieved. The specimens were processed with the Precise 1 Automated System to obtain thin ground sections. A total of 3 slides were obtained for each implant. The slides were stained with acid and basic fuchsin and toluidine blue. The slides were observed in normal transmitted light under a Leitz Laborlux microscope, and histomorphometric analysis was performed. With the machined implants, it was possible to observe the presence of bone trabeculae near the implant surface at low magnification. At higher magnification many actively secreting alkaline phosphatasepositive (ALP+) osteoblasts were observed. In many areas, a not yet mineralized matrix was present. After 4 to 8 weeks, mature bone appeared in direct contact with the implant surface, but in many areas a not yet mineralized osteoid matrix was interposed between the mineralized bone and implant surface. In the RBM implants, many ALP+ osteoblasts were present and in direct contact with

  5. Survival of Dental Implants Placed in Grafted and Nongrafted Bone: A Retrospective Study in a University Setting.

    Science.gov (United States)

    Tran, Duong T; Gay, Isabel C; Diaz-Rodriguez, Janice; Parthasarathy, Kavitha; Weltman, Robin; Friedman, Lawrence

    2016-01-01

    To compare dental implant survival rates when placed in native bone and grafted sites. Additionally, risk factors associated with dental implant loss were identified. This study was based on the hypothesis that bone grafting has no effect on implant survival rates. A retrospective chart review was conducted for patients receiving dental implants at the University of Texas, School of Dentistry from 1985 to 2012. Exclusion criteria included patients with genetic diseases, radiation and chemotherapy, or an age less than 18 years. To avoid misclassification bias, implants were excluded if bone grafts were only done at the same time of placement. Data on age, sex, tobacco use, diabetes, osteoporosis, anatomical location of the implant, implant length and width, bone graft, and professional maintenance were collected for analysis. A total of 1,222 patients with 2,729 implants were included. The cumulative survival rates at 5 and 10 years were 92% and 87% for implants placed in native bone and 90% and 79% for implants placed in grafted bone, respectively. The results from multivariate analysis (Cox regression) indicated no significant difference in survival between the two groups; having maintenance therapy after implant placement reduced the failure rate by 80% (P dental implant survival rate when implants were placed in native bone or bone-grafted sites. Smoking and lack of professional maintenance were significantly related to increased implant loss.

  6. Photoemission studies of amorphous silicon induced by P + ion implantation

    Science.gov (United States)

    Petö, G.; Kanski, J.

    1995-12-01

    An amorphous Si layer was formed on a Si (1 0 0) surface by P + implantation at 80 keV. This layer was investigated by means of photoelectron spectroscopy. The resulting spectra are different from earlier spectra on amorphous Si prepared by e-gun evaporation or cathode sputtering. The differences consist of a decreased intensity in the spectral region corresponding to p-states, and appearace of new states at higher binding energy. Qualitativity similar results have been reported for Sb implanted amorphous Ge and the modification seems to be due to the changed short range order.

  7. Progenitor Hematopoietic Cells Implantation Improves Functional Capacity of End Stage Coronary Artery Disease Patients with Advanced Heart Failure

    Directory of Open Access Journals (Sweden)

    Yoga Yuniadi

    2016-01-01

    Full Text Available Background. Proangiogenic Hematopoietic Cells (PHC which comprise diverse mixture of cell types are able to secrete proangiogenic factors and interesting candidate for cell therapy. The aim of this study was to seek for benefit in implantation of PHC on functional improvement in end stage coronary artery disease patients with advanced heart failure. Methods. Patients with symptomatic heart failure despite guideline directed medical therapy and LVEF less than 35% were included. Peripheral blood mononuclear cells were isolated, cultivated for 5 days, and then harvested. Flow cytometry and cell surface markers were used to characterize PHC. The PHC were delivered retrogradely via sinus coronarius. Echocardiography, myocardial perfusion, and clinical and functional data were analyzed up to 1-year observation. Results. Of 30 patients (56.4±7.40 yo preimplant NT proBNP level is 5124.5±4682.50 pmol/L. Harvested cells characterized with CD133, CD34, CD45, and KDR showed 0.87±0.41, 0.63±0.66, 99.00±2.60, and 3.22±3.79%, respectively. LVEF was improved (22±5.68 versus 26.8±7.93, p<0.001 during short and long term observation. Myocardial perfusion significantly improved 6 months after treatment. NYHA Class and six-minute walk test are improved during short term and long term follow-up. Conclusion. Expanded peripheral blood PHC implantation using retrograde delivery approach improved LV systolic function, myocardial perfusion, and functional capacity.

  8. Computer-aided insertion of endosteal implants in the zygoma: a pilot study

    Science.gov (United States)

    Birkfellner, Wolfgang; Watzinger, Franz; Wanschitz, Felix; Ziya, F.; Kremser, J.; Potyka, A.; Mayr, R.; Huber, Klaus; Kainberger, F.; Ewers, Rolf; Bergmann, Helmar

    2000-04-01

    Endosteal implants facilitate obturator prosthesis fixation in tumor patients after maxillectomy. Previous clinical studies shown however, that survival of implants placed into available bone after maxillectomy is generally poor. Implants positioned optimally in residual zygomatic bone provide superior stability form a biomechanical point of view as well as improved survival. In a pilot study, we have assessed the precision of VISIT, a surgical navigation system developed for research purposes at our institution. VISIT is based on the AVW-library and a number of in-house developed algorithms for communication with an optical tracker and patient-to-CT-registration. The final platform independent application was assembled within 6 man-months using ANSI-C and Tcl/Tk. Five cadaver specimens underwent hemimaxillectomy. The cadaver head was matched to a preoperative high resolution CT by using implanted surgical microscrews as fiducial markers. The position of a surgical drill relative to the cadaver head was determined with an optical tracking system. Implants were placed into the zygomatic arch where maximum bone volume was available. The results were assessed using test for allocation accuracy and postoperative CT-scans of the cadaver specimens. The average allocation accuracy of landmarks on the bony skull was 0.6 +/- 0.3 mm determined with a 5 degree-of-freedom pointer probe. The allocation accuracy of the tip of the implant burr was 1.7 +/- 0.4 mm. The accuracy of the implant position compared to the planned position was 1.5 +/- 1.1 mm. 8 out of 10 implants were inserted with maximum contact to surrounding bone, two implants were located unfavorably. However, reliable placement of implants in this region is difficult to achieve. The techqni3u described in this paper may be very helpful in the management of patients after maxillary resection without sufficient retention for obturator prostheses.

  9. Hydroxyapatite nanocrystals functionalized with alendronate as bioactive components for bone implant coatings to decrease osteoclastic activity

    Science.gov (United States)

    Bosco, Ruggero; Iafisco, Michele; Tampieri, Anna; Jansen, John A.; Leeuwenburgh, Sander C. G.; van den Beucken, Jeroen J. J. P.

    2015-02-01

    The integration of bone implants within native bone tissue depends on periprosthetic bone quality, which is severely decreased in osteoporotic patients. In this work, we have synthesized bone-like hydroxyapatite nanocrystals (nHA) using an acid-base neutralization reaction and analysed their physicochemical properties. Subsequently, we have functionalized the nHA with alendronate (nHAALE), a well-known bisphosphonate drug used for the treatment of osteoporosis. An in vitro osteoclastogenesis test was carried out to evaluate the effect of nHAALE on the formation of osteoclast-like cells from monocytic precursor cells (i.e. RAW264.7 cell line) showing that nHAALE significantly promoted apoptosis of osteoclast-like cells. Subsequently, nHA and nHAALE were deposited on titanium disks using electrospray deposition (ESD), for which characterisation of the deposited coatings confirmed the presence of alendronate in nHAALE coatings with nanoscale thickness of about 700 nm. These results indicate that alendronate linked to hydroxyapatite nanocrystals has therapeutic potential and nHAALE can be considered as an appealing coating constituent material for orthopaedic and oral implants for application in osteoporotic patients.

  10. Biomechanical evaluation of implant-supported prosthesis with various tilting implant angles and bone types in atrophic maxilla: A finite element study.

    Science.gov (United States)

    Gümrükçü, Zeynep; Korkmaz, Yavuz Tolga; Korkmaz, Fatih Mehmet

    2017-07-01

    The purpose of this study is to evaluate and compare bone stress that occurs as a result of using vertical implants with simultaneous sinus augmentation with bone stress generated from oblique implants without sinus augmentation in atrophic maxilla. Six, three-dimensional (3D) finite element (FE) models of atrophic maxilla were generated with SolidWorks software. The maxilla models were varied for two different bone types. Models 2a, 2b and 2c represent maxilla models with D2 bone type. Models 3a, 3b and 3c represent maxilla models with D3 bone type. Five implants were embedded in each model with different configurations for vertical implant insertion with sinus augmentation: Model 2a/Model 3a, 30° tilted insertion; Model 2b/Model 3b and 45° tilted insertion; Model 2c/Model 3c. A 150 N load was applied obliquely on the hybrid prosthesis. The maximum von Mises stress values were comparatively evaluated using color scales. The von Mises stress values predicted by the FE models were higher for all D3 bone models in both cortical and cancellous bone. For the vertical implant models, lower stress values were found in cortical bone. Tilting of the distal implants by 30° increased the stress in the cortical layer compared to vertical implant models. Tilting of the distal implant by 45° decreased the stress in the cortical bone compared to the 30° models, but higher stress values were detected in the 45° models compared to the vertical implant models. Augmentation should be the first treatment option in atrophic maxilla in terms of biomechanics. Tilted posterior implants can create higher stress values than vertical posterior implants. During tilting implant planning, the use of a 45° tilted implant results in better biomechanical performance in peri-implant bone than 30° tilted implant due to the decrease in cantilever length. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Morphological and functional characteristics of three-dimensional engineered bone-ligament-bone constructs following implantation.

    Science.gov (United States)

    Ma, Jinjin; Goble, Kristen; Smietana, Michael; Kostrominova, Tatiana; Larkin, Lisa; Arruda, Ellen M

    2009-10-01

    The incidence of ligament injury has recently been estimated at 400,000/year. The preferred treatment is reconstruction using an allograft, but outcomes are limited by donor availability, biomechanical incompatibility, and immune rejection. The creation of an engineered ligament in vitro solely from patient bone marrow stromal cells (has the potential to greatly enhance outcomes in knee reconstructions. Our laboratory has developed a scaffoldless method to engineer three-dimensional (3D) ligament and bone constructs from rat bone marrow stem cells in vitro. Coculture of these two engineered constructs results in a 3D bone-ligament-bone (BLB) construct with viable entheses, which was successfully used for medial collateral ligament (MCL) replacement in a rat model. 1 month and 2 month implantations were applied to the engineered BLBs. Implantation of 3D BLBs in a MCL replacement application demonstrated that our in vitro engineered tissues grew and remodeled quickly in vivo to an advanced phenotype and partially restored function of the knee. The explanted 3D BLB ligament region stained positively for type I collagen and elastin and was well vascularized after 1 and 2 months in vivo. Tangent moduli of the ligament portion of the 3D BLB 1 month explants increased by a factor of 2.4 over in vitro controls, to a value equivalent to those observed in 14-day-old neonatal rat MCLs. The 3D BLB 1 month explants also exhibited a functionally graded response that closely matched native MCL inhomogeneity, indicating the constructs functionally adapted in vivo.

  12. A Longitudinal Study in Adults with Sequential Bilateral Cochlear Implants: Time Course for Individual Ear and Bilateral Performance

    Science.gov (United States)

    Reeder, Ruth M.; Firszt, Jill B.; Holden, Laura K.; Strube, Michael J.

    2014-01-01

    Purpose: The purpose of this study was to examine the rate of progress in the 2nd implanted ear as it relates to the 1st implanted ear and to bilateral performance in adult sequential cochlear implant recipients. In addition, this study aimed to identify factors that contribute to patient outcomes. Method: The authors performed a prospective…

  13. Evolution of bone biomechanical properties at the micrometer scale around titanium implant as a function of healing time

    Science.gov (United States)

    Vayron, Romain; Matsukawa, Mami; Tsubota, Ryo; Mathieu, Vincent; Barthel, Etienne; Haiat, Guillaume

    2014-03-01

    The characterization of the biomechanical properties of newly formed bone tissue around implants is important to understand the osseointegration process. The objective of this study is to investigate the evolution of elastic properties of newly formed bone tissue as a function of healing time. To do so, nanoindentation and micro-Brillouin scattering techniques are coupled following a multimodality approach using histological analysis. Coin-shaped implants were placed in vivo at a distance of 200 µm from the cortical bone surface, leading to an initially empty cavity. Two rabbits were sacrificed after 7 and 13 weeks of healing time. The histological analyses allow us to distinguish mature and newly formed bone tissue. The bone mechanical properties were measured in mature and newly formed bone tissue. Analysis of variance and Tukey-Kramer tests reveals a significant effect of healing time on the indentation modulus and ultrasonic velocities of bone tissue. The results show that bone mass density increases by 12.2% (2.2% respectively) between newly formed bone at 7 weeks (13 weeks respectively) and mature bone. The dependence of bone properties on healing time may be explained by the evolution of bone microstructure and mineralization.

  14. Functional jaw muscle assessment in patients with a full fixed prosthesis on a limited number of implants: a review of the literature.

    Science.gov (United States)

    Dellavia, Claudia; Rosati, Riccardo; Del Fabbro, Massimo; Pellegrini, Gaia

    2014-01-01

    Full fixed prosthesis on a limited number of implants (FFP) are a viable treatment option for edentulous patients with a reduced amount of residual bone. Jaw muscular function in FFP patients has been evaluated in several studies, however heterogeneous data emerge from literature. The aim of this review of the literature was to assess the function of jaw muscles in edentulous patients restored with full fixed prostheses on a limited number (≤ 6) of implants, as compared to dentate subjects and edentulous subjects wearing dentures, implant-supported overdentures or full fixed prostheses supported by more than six implants. An electronic search of databases up to December 2013 was performed. The articles were selected using specific inclusion criteria, independent of the study design. A total of 1598 records were identified. After removing the duplicates and excluding records based on title and abstract, only 37 eligible records were identified. After full-text review, seventeen studies were selected for analysis according to the inclusion criteria. From the included studies, only one evaluated masseter muscle thickness in a cross sectional study by means of ultrasound, while the 16 remaining papers evaluated muscular function by using electromyography (EMG). Those studies analysed several heterogeneous parameters throughout the execution of five functional tests and were therefore described and pooled according to the following task categories: clenching; swallowing; reflex and fatigue for statics; and chewing for dynamics. The results of selected studies seem to indicate that, compared to dentate controls, FFP patients display a global satisfactory neuromuscular equilibrium in static activities, but still have some impairment during chewing.

  15. Nanohydroxyapatite Silicate-Based Cement Improves the Primary Stability of Dental Implants: An In Vitro Study

    Directory of Open Access Journals (Sweden)

    Hooman Khorshidi

    2017-01-01

    Full Text Available Objectives. Insufficient cortical bone volume when placing implants can lead to lack of primary stability. The use of cement as a bone fill material in bone defects around dental implant could result in better clinical outcome. HA has shown excellent biological properties in implant dentistry. The purpose of this study was to evaluate the effect of nanohydroxyapatite powder (Nano-HA in combination with accelerated Portland cement (APC on implant primary stability in surgically created circumferential bone defects in a bovine rib in vitro model. Materials and Methods. Sixteen bovine rib bones and thirty-six implants of same type and size (4 mm × 10 mm were used. Implants were divided into six groups: no circumferential bone defect, defect and no grafting, bone chips grafting, Nano-HA grafting, APC grafting, and Nano-HA mixed to APC grafting (Nano-HA-APC. Circumferential defects around the implants were prepared. The implant stability quotient (ISQ values were measured before and after the grafting. Results. APC exhibited the highest ISQ values. A significant increase of ISQ values following the grafting of Nano-HA-APC (18.08±5.82 and APC alone (9.50±4.12 was achieved. Increase of ISQ values after 72 hours was 24.16±5.01 and 17.58±4.89, respectively. Nano-HA grafting alone exhibited the least rise in ISQ values. Conclusions. Nanohydroxyapatite silicate-based cement could improve the primary stability of dental implants in circumferential bone defect around implants.

  16. Three-Dimensional Evaluation of Implant Positioning in the Maxillary Sinus Septum: A Retrospective Study

    Science.gov (United States)

    Dragan, Eliza; Guillaume, Odri A.; Haba, Danisia; Olszewski, Raphael

    2015-01-01

    Background The aim of this study was to simulate implant placement in the maxillary sinus septum, as a potential alternative site to avoid sinus grafting. Material/Methods One hundred partially or completely edentulous patients, with their maxillary sinus septum present in the edentulous region, were selected from the database of the Department of Maxillofacial Surgery, Cliniques Universitaires Saint Luc, Bruxelles, Belgium. Three-dimensional (3D) reconstructions were created using 3D planning software. 3D reconstructions were performed for each maxillary sinus. Using the software implant library, the implants that presented the best fit with the maxillary sinus septum and that followed the established inclusion criteria were selected. Results All of the implants were inserted in premolar and molar regions. Most implants were inserted in the position of the second molar (21 of 55) or in the position of the first molar (17 of 55). In all sites the most frequently used implant was 4 mm in diameter and 7 mm in height. The mean coronal angle for the implant was 80.19±17.13 degrees and the mean sagittal angle was 94.83±9.94 degrees. The septal height represents 38.13% of the total available bone height (ABH). The mean percentage of the septum used to insert the implants was 47.33±2.47%. The septum increased the available bone height by a mean value of 2.18±1.47 mm. In 45 cases, the septa did not permit implant placement. Conclusions In completely edentulous patients, inserting implants in sinus septa does not exclude the need for sinus grafting, but in partially edentulous patients, this minimally invasive technique is an alternative to subantral augmentation. PMID:26363865

  17. A 10-Year Prospective Study of Single Tooth Implants Placed in the Anterior Maxilla

    DEFF Research Database (Denmark)

    Gotfredsen, Klaus

    2012-01-01

    in this study. Ten implants were placed with an early placement protocol, that is, 4 weeks after tooth extraction, whereas the other 10 implants were placed with a conventional delayed placement protocol, for example, 12 weeks after tooth extraction. At the baseline and at the annual re-examinations, pain from......Purpose: The aim of the study was to evaluate the biological and technical outcomes of early and delayed placed single tooth implants after 10 years of follow-up. Materials and Methods: Twenty consecutive patients who needed a single tooth replacement in the anterior maxilla were included...

  18. Communication Intervention for Children with Cochlear Implants: Two Case Studies.

    Science.gov (United States)

    Ertmer, David J.; Leonard, Jeannette S.; Pachuilo, Michael L.

    2002-01-01

    This article describes the intervention programs attended and progress made by two children (ages 3 and 7) who exhibited considerable differences in benefit from their cochlear implants. Their intervention programs employed both analytical and synthetic auditory training and emphasized the development of speech production and language skills.…

  19. Study of boron implantation in Ag-Si layer structures

    Energy Technology Data Exchange (ETDEWEB)

    Pelikan, L. (Ceske Vysoke Uceni Technicke, Prague (Czechoslovakia). Fakulta Elektrotechnicka); Rybka, V.; Krejci, P. (Tesla, Prague (Czechoslovakia). Vyzkumny Ustav pro Sdelovaci Techniku); Hnatowicz, V.; Kvitek, J. (Ustav Jaderneho Vyzkumu CSKAE, Rez (Czechoslovakia))

    1982-07-16

    The implanted boron depth profiles in samples comprising Si wafers covered with Ag films of various thicknesses are determined experimentally as well as by Monte-Carlo simulation. A complex shape of depth profiles is revealed, which is well reproduced by the calculation.

  20. Comparison of Osteotome and Conventional Drilling Techniques for Primary Implant Stability: An In Vitro Study.

    Science.gov (United States)

    Tsolaki, Ioanna N; Tonsekar, Pallavi P; Najafi, Babak; Drew, Howard J; Sullivan, Andrew J; Petrov, Sofia D

    2016-08-01

    It may be difficult to achieve primary stability in the posterior maxilla because of poor quality and quantity of bone. Studies have shown that the osteotome technique immediately increases bone density thereby increasing primary stability. An in vitro study was conducted to compare the stability achieved by the osteotome and conventional drilling techniques in low density bone. Forty endosseous implant fixtures (n = 40) were inserted in a solid rigid polyurethane block simulating low density (D3) bone. The implants were divided into 4 groups to test 2 variables: (1) implant length (10 mm or 13 mm) and (2) preparation of osteotomy (conventional drilling or osteotome technique). Insertion torque (IT) and resonance frequency analysis (RFA) were measured for each implant. Statistical analysis using one-way ANOVA and Tukey post hoc test was done to study IT and RFA data of the 4 groups. Pearson Correlation test was used to determine the correlation between IT and RFA values of the implants. The IT and RFA values were statistically significant higher using the osteotome technique as compared to conventional drilling (P < 0.0001). Statistically significant higher values were also found for IT and RFA of 13 mm implants as compared to 10 mm implants. A significant correlation was found between insertion torque and RFA values in all 4 groups (r = 0.86, P < 0.0001). The conclusion was that the osteotome technique significantly increased primary stability.

  1. Long-term implant prognosis in patients with and without a history of chronic periodontitis: a 10-year prospective cohort study of the ITI Dental Implant System.

    Science.gov (United States)

    Karoussis, Ioannis K; Salvi, Giovanni E; Heitz-Mayfield, Lisa J A; Brägger, Urs; Hämmerle, Christoph H F; Lang, Niklaus P

    2003-06-01

    The aim of this 10-year study was to compare the failure, success and complication rates between patients having lost their teeth due to periodontitis or other reasons. Fifty-three patients who received 112 hollow screw implants (HS) of the ITI Dental Implant System were divided into two groups: group A - eight patients with 21 implants having lost their teeth due to chronic periodontitis; group B - forty five patients with 91 implants without a history of periodontitis. One and 10 years after surgical placement, clinical and radiographic parameters were assessed. The incidences of peri-implantitis were noticed over the 10 years of regular supportive periodontal therapy. Success criteria at 10 years were set at: pocket probing depth (PPD) periodontitis (group A) was 90.5%, while for the group with no past history of periodontitis (group B) it was 96.5%. Group A had a significantly higher incidence of peri-implantitis than group B (28.6% vs. 5.8%). With the success criteria set, 52.4% in group A and 79.1% of the implants in group B were successful. With a threshold set at PPD periodontitis demonstrated lower survival rates and more biological complications than patients with implants replacing teeth lost due to reasons other than periodontitis during a 10-year maintenance period. Furthermore, setting of thresholds for success criteria is crucial to the reporting of success rates.

  2. Study on the Properties of TiN Coatings on Previously Ion-Implanted Pure Magnesium Surface by MEVVA Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Hai; CHEN Fei; WANG Jian-ping

    2007-01-01

    A metal vapor vacuum arc (MEVVA) is used in ion implantation for substrate preparation before the deposition process which would ensure the improvement of mechanical properties of the coating.Ti ion is implanted into pure magnesium surface by MEVVA implanter operated with a modified cathode.Implanting energy is kept at 45 keV and dose is set at 3×1017 cm-2.TiN coatings are deposited by magnetically filtered vacuum-arc plasma source on unimplanted and previously implanted substrates.Microstructure and phase composition are analysed using scanning electron microscopy (SEM) and X-ray diffraction (XRD).The property of corrosion resistance of TiN coatings was studied by CS300P electrochemistry-corrosion workstation,and the main impact factor of the corrosion resistance was also analyzed.

  3. Bone regenerating effect of surface-functionalized titanium implants with sustained-release characteristics of strontium in ovariectomized rats

    Directory of Open Access Journals (Sweden)

    Offermanns V

    2016-05-01

    Full Text Available Vincent Offermanns,1 Ole Zoffmann Andersen,2 Gregor Riede,1 Inge Hald Andersen,3 Klaus Pagh Almtoft,3 Søren Sørensen,3 Michael Sillassen,2 Christian Sloth Jeppesen,3 Michael Rasse,1 Morten Foss,2 Frank Kloss1 1Department of Cranio-, Maxillofacial and Oral Surgery, Medical University Innsbruck, Innsbruck, Austria; 2Interdisciplinary Nanoscience Center (iNANO, Faculty of Science and Technology, Aarhus University, Aarhus, Denmark; 3Tribology Centre, Danish Technological Institute, Aarhus, Denmark Abstract: Since strontium (Sr is known for its anabolic and anticatabolic effect on bone, research has been focused on its potential impact on osseointegration. The objective of this study was to investigate the performance of nanotopographic implants with a Sr-functionalized titanium (Ti coating (Ti–Sr–O with respect to osseointegration in osteoporotic bone. The trial was designed to examine the effect of sustained-release characteristics of Sr in poor-quality bone. Three Ti–Sr–O groups, which differed from each other in coating thickness, Sr contents, and Sr release, were examined. These were prepared by a magnetron sputtering process and compared to uncoated grade 4 Ti. Composition, morphology, and mechanical stability of the coatings were analyzed, and Sr release data were gained from in vitro washout experiments. In vivo investigation was carried out in an osteoporotic rat model and analyzed histologically, 6 weeks and 12 weeks after implantation. Median values of bone-to-implant contact and new bone formation after 6 weeks were found to be 84.7% and 54.9% (best performing Sr group as compared to 65.2% and 23.8% (grade 4 Ti reference, respectively. The 12-week observation period revealed 84.3% and 56.5% (best performing Sr group and 81.3% and 39.4% (grade 4 Ti reference, respectively, for the same measurements. The increase in new bone formation was found to correlate with the amount of Sr released in vitro. The results indicate that

  4. CNC-milled titanium frameworks supported by implants in the edentulous jaw: a 10-year comparative clinical study.

    Science.gov (United States)

    Örtorp, Anders; Jemt, Torsten

    2012-03-01

    No long-term clinical studies covering more than 5 years are available on Computer Numeric Controlled (CNC) milled titanium frameworks. To evaluate and compare the clinical and radiographic performance of implant-supported prostheses provided with CNC titanium frameworks in the edentulous jaw with prostheses with cast gold-alloy frameworks during the first 10 years of function. Altogether, 126 edentulous patients were by random provided with 67 prostheses with titanium frameworks (test) in 23 maxillas and 44 mandibles, and with 62 prostheses with gold-alloy castings (control) in 31 maxillas and 31 mandibles. Clinical and radiographic 10-year data were collected for the groups and statistically compared on patient level. The 10-year prosthesis and implant cumulative survival rate was 95.6% compared with 98.3%, and 95.0% compared with 97.9% for test and control groups, respectively (p > .05). No implants were lost after 5 years of follow-up. Smokers lost more implants than nonsmokers after 5 years of follow-up (p .05), respectively. One prosthesis was lost in each group due to loss of implants, and one prosthesis failed due to framework fracture in the test group. Two metal fractures were registered in each group. More appointments of maintenance were needed for the prostheses in the maxilla compared with those in the mandible (p CNC-milled titanium frameworks are a viable alternative to gold-alloy castings for restoring patients with implant-supported prostheses in the edentulous jaw. © 2009 Wiley Periodicals, Inc.

  5. 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.

  6. Does the number of implants have any relation with peri-implant disease?

    Science.gov (United States)

    PASSONI, Bernardo Born; DALAGO, Haline Renata; SCHULDT FILHO, Guenther; OLIVEIRA DE SOUZA, João Gustavo; BENFATTI, César Augusto Magalhães; MAGINI, Ricardo de Souza; BIANCHINI, Marco Aurélio

    2014-01-01

    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 (pImplants 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. PMID:25466474

  7. Cross-sectional analysis of the implant-abutment interface.

    Science.gov (United States)

    Coelho, A L; Suzuki, M; Dibart, S; DA Silva, N; Coelho, P G

    2007-07-01

    The purpose of this study was to develop a technique to evaluate the implant-abutment gap of an external hexagon implant system as a function of radius. Six implants of 3.75 mm in diameter (Conexao Sistema de Protese Ltda, Sao Paulo, Brazil) and their respective abutments were screw connected and torqued to 20 N cm(-1). The implants were mounted in epoxy assuring an implant long-axis position perpendicular to the vertical axis. Each implant was grounded through its thickness parallel to implant long-axis at six different distance interval. Implant-abutment gap distances were recorded along the implant-abutment region for each section. Individual measurements were related to their radial position through trigonometric inferences. A sixth degree polynomial line fit approach determined radial adaptation patterns for each implant. Micrographs along implant sections showed a approximately 300 mum length implant-abutment engagement region. All implants presented communication between external and internal regions through connection gaps and inaccurate implant-abutment alignment. Average gap distances were not significantly different between implants (P > 0.086). Polynomial lines showed implant-abutment gap values below 10 mum from 0 mum to approximately 250 mum of the implant-abutment engagement region. Gap distances significantly increased from approximately 250 mum to the outer radius of the implant-abutment engagement region. The technique described provided a broader scenario of the implant-abutment gap adaptation compared with previous work concerning implant-abutment gap determination, and should be considered for better understanding mechanical aspects or biological effects of implant-abutment adaptation on peri-implant tissues.

  8. Osteotome versus conventional drilling technique for implant site preparation: a comparative study in the rabbit.

    Science.gov (United States)

    Nóbrega, Ana Rita; Norton, Ana; Silva, José Antonio; Silva, José Pedro Dias; Branco, Fernando Morais; Anitua, Eduardo

    2012-06-01

    The aim of this research was to study the influence of the osteotome technique on insertion torque and stability values when compared with conventional surgical drilling of the implant site. A total of 20 implants (4-mm diameter, 8.5-mm long) were placed in the distal femural condyle of 10 New Zealand White rabbits. The implant sites were prepared by using either the conventional drilling technique as a control group (group A) or the osteotome technique (group B). Cutting torque and resonance frequency analyses (RFAs) were conducted at and after implant placement. The resulting values were subjected to correlation and comparative analyses between groups. Insertion torque measurements were conducted at three different levels of implant insertion: crestal, middle, and apical. Group B showed higher mean insertion torque and RFA values (P .05). Bone condensation before implant insertion in low-density bone led to higher mean insertion torque and RFA values. Within the limits of this experimental study, a benefit in using the osteotome technique was observed when dealing with low-density bone. Bone condensation can improve primary stabilization of implants.

  9. Rutherford Backscattering Spectrometry studies of 100 keV nitrogen ion implanted polypropylene polymer

    Science.gov (United States)

    Chawla, Mahak; Aggarwal, Sanjeev; Sharma, Annu

    2017-09-01

    The effect of nitrogen ion implantation on the structure and composition in polypropylene (PP) polymer has been studied. Implantation was carried out using 100 keV N+ ions at different fluences of 1 × 1015, 1 × 1016 and 1 × 1017 ions cm-2 with beam current density of ∼0.65 μA cm-2. Surface morphological changes in the pre- and post-implanted PP specimens have been studied using Rutherford Backscattering Spectrometry (RBS) and UV-Visible Spectroscopy. The spatial distribution of implantation induced modification in the form of carbonization and dehydrogenation in the near surface region of PP matrix, the projected range, retained dose of implanted nitrogen, the various elements present in the implanted layers and their differential cross-sections have been analyzed using RBS spectra. RUMP simulation yielded an increase in the concentration of carbon near the surface from 33 at.% (virgin) to 42 at.% at fluence of 1 × 1017 N+ cm-2. Further, optical absorption has been found to increase with a shift in the absorption edge from UV towards visible region with increasing fluence. UV-Vis absorption spectra also indicate a drastic decrease in optical energy gap from 4.12 eV (virgin) to 0.25 eV (1 × 1017 N+ cm-2) indicating towards the formation of carbonaceous network in the implanted region. All these changes observed using UV-Visible have been further correlated with the outcomes of the RBS characterization.

  10. Occurrence of trigeminocardiac reflex during dental implant surgery: An observational prospective study.

    Science.gov (United States)

    Huang, James I-Sheng; Yu, Hui-Chieh; Chang, Yu-Chao

    2017-10-01

    Trigeminocardiac reflex (TCR) is a clinical phenomenon that manifests as s sudden onset of hemodynamic perturbations. TCR has been reported in cranio-maxillofacial surgery resulting in severe medical risks. Monitoring the hemodynamic changes during cranio-maxillofacial surgery can provide important information to ensure the continuous evaluation of patient's physical conditions. This prospective observational study was conducted to determine the hemodynamic alterations related to the possibly of occurrence of TCR in patients during dental implant surgery. One hundred and thirty-five patients (69 males and 66 females) received dental implant placement were enrolled in this study. The hemodynamic changes were evaluated by monitoring heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), and pulse oximetry (SpO2). The above data were collected before, during, and after dental implant surgery. The data demonstrated that the minimal values of HR, SBP, and DBP as well as MABP decreased significantly during operation comparing with the corresponding values before operation (p implant placement in the mandible, patients received dental implant placement in the maxilla had more risks to confront with MABP reduction (OR = 3.98; 95% confidence interval: 1.12-13.2). A significant HR and BP reduction possibly due to TCR can occur during dental implant surgery. Therefore, the dentists should monitor the hemodynamic changes during dental implant surgery to prevent the possible occurrence of medical risks related to TCR. Copyright © 2017. Published by Elsevier B.V.

  11. Survival Rate of Short, Locking Taper Implants with a Plateau Design: A 5-Year Retrospective Study

    Directory of Open Access Journals (Sweden)

    Kemal Özgür Demiralp

    2015-01-01

    Full Text Available Background. Short implants have become popular in the reconstruction of jaws, especially in cases with limited bone height. Shorter implants, those with locking tapers and plateau root shapes, tend to have longer survival times. We retrospectively investigated the cumulative survival rates of Bicon short implants (<8 mm according to patient variables over a 5-year period. Materials and Methods. This study included 111 consecutively treated patients with 371 implants supporting fixed or removable prosthetics. Data were evaluated to acquire cumulative survival rates according to gender, age, tobacco use, surgical procedure, bone quality, and restoration type. Statistics were performed using chi-square, Mann-Whitney, and Kruskal Wallis H tests. Results. The survival rate was 97.3% with, on average, 22.8 months of follow-up. Patients older than 60 years had higher failure rate than the other age groups (P<0.05. Placed region, age, and bone quality had adverse effects on survival rate in the <8 mm implant group with statistically significant difference (P<0.05. Conclusions. Approximately 23-month follow-up data indicate that short implants with locking tapers and plateau-type roots have comparable survival rates as other types of dental implants. However, due to limitations of study, these issues remain to be further investigated in future randomized controlled clinical trials.

  12. Experimental study on penetration of dental implants into the maxillary sinus in different depths

    National Research Council Canada - National Science Library

    ZHONG, Weijian; CHEN, Binke; LIANG, Xin; MA, Guowu

    2013-01-01

    ...: The purpose of this study was to investigate the effects of the dental implant penetration into the maxillary sinus cavity in different depths on osseointegration and sinus health in a dog model...

  13. One-year cardiac morphological and functional evolution following permanent pacemaker implantation in right ventricular septal position in chagasic patients

    Directory of Open Access Journals (Sweden)

    Otaviano da Silva Júnior

    2012-06-01

    Full Text Available INTRODUCTION: The septal position is an alternative site for cardiac pacing (CP that is potentially less harmful to cardiac function. METHODS: Patients with Chagas disease without heart failure submitted to permanent pacemaker (PP implantation at the Clinics Hospital of the Triângulo Mineiro Federal University (UFTM, were selected from February 2009 to February 2010. The parameters analyzed were ventricular remodeling, the degree of electromechanical dyssynchrony (DEM, exercise time and VO2 max during exercise testing (ET and functional class (NYHA. Echocardiography was performed 24 to 48h following implantation and after one year follow-up. The patients were submitted to ET one month postprocedure and at the end of one year. RESULTS: Thirty patients were included. Patient mean age was 59±13 years-old. Indication for PP implantation was complete atrioventricular (AV block in 22 (73.3% patients and 2nd degree AV block in the other eight (26.7%. All patients were in NYHA I and no changes occurred in the ET parameters. No variations were detected in echocardiographic remodeling measurements. Intraventricular dyssynchrony was observed in 46.6% of cases and interventricular dyssynchrony in 33.3% of patients after one year. CONCLUSIONS: The findings of this work suggest that there is not significant morphological and functional cardiac change following pacemaker implantation in septal position in chagasic patients with normal left ventricular function after one year follow-up. Thus, patients may remain asymptomatic, presenting maintenance of functional capacity and no left ventricular remodeling.

  14. Effects of implant angulation, material selection, and impression technique on impression accuracy: a preliminary laboratory study.

    Science.gov (United States)

    Rutkunas, Vygandas; Sveikata, Kestutis; Savickas, Raimondas

    2012-01-01

    The aim of this preliminary laboratory study was to evaluate the effects of 5- and 25-degree implant angulations in simulated clinical casts on an impression's accuracy when using different impression materials and tray selections. A convenience sample of each implant angulation group was selected for both open and closed trays in combination with one polyether and two polyvinyl siloxane impression materials. The influence of material and technique appeared to be significant for both 5- and 25-degree angulations (P impression accuracy. The open-tray technique was more accurate with highly nonaxially oriented implants for the small sample size investigated.

  15. Monte Carlo studies of positron implantation in elemental metallic and multilayer systems

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, V.J.; Welch, D.O.; Lynn, K.G.

    1992-01-01

    We have used a Monte Carlo computer code developed at Brookhaven [sup 1,2] to study the implantation profiles of 1-10 keV positrons incident on a wide range of semi-infinite metals and multilayer systems. Our Monte Carlo program accounts for elastic scattering as well as inelastic scattering from core and valence electrons, and includes the excitation of plasmons. The implantation profiles of positrons in many metals as well as Pd/Al, and Al/Co/Si multilayers are presented. Scaling relations and closed-form expressions representing he implantation profiles are also discussed.

  16. Monte Carlo studies of positron implantation in elemental metallic and multilayer systems

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, V.J.; Welch, D.O.; Lynn, K.G.

    1992-12-01

    We have used a Monte Carlo computer code developed at Brookhaven {sup 1,2} to study the implantation profiles of 1-10 keV positrons incident on a wide range of semi-infinite metals and multilayer systems. Our Monte Carlo program accounts for elastic scattering as well as inelastic scattering from core and valence electrons, and includes the excitation of plasmons. The implantation profiles of positrons in many metals as well as Pd/Al, and Al/Co/Si multilayers are presented. Scaling relations and closed-form expressions representing he implantation profiles are also discussed.

  17. Surface characteristics and cell adhesion: a comparative study of four commercial dental implants.

    Science.gov (United States)

    Liu, Ruohong; Lei, Tianhua; Dusevich, Vladimir; Yao, Xiamei; Liu, Ying; Walker, Mary P; Wang, Yong; Ye, Ling

    2013-12-01

    The aims of this study were to compare surface properties of four commercial dental implants and to compare those implant systems' cell adhesion, which may be affected by the surface properties, and to provide scientific information on the selection of implants for clinicians. The surface properties of four commonly used dental implants (3i Nanotite™, Astra OsseoSpeed™, Nobel Biocare TiUnite®, and Straumann SLActive®) were studied using MicroSpy profiler, scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy, and Raman microspectroscopy. Primary mouse alveolar bone cells were cultured on the surface of implants from the four companies. After 48-hour culture, SEM in combination with a quantitative analysis of SEM images was used to examine the cell adhesion. Cell adhesion rates (ratios of cell surface to implant surface) among different systems were compared. Distinct differences were found among these implants. Comparisons of roughness among three locations: flank, top, and valley within the same implant system, or in the same location among different implants were made. Generally Astra and Straumann systems showed the roughest surface, whereas 3i showed the smoothest surface. Multiple cracks were found on the surface of the Nobel Biocare system, which also had a dramatically lower level of titanium. In addition, rutile phase of titanium oxide was found in 3i, Astra, and Straumann systems, and anatase phase of titanium oxide was only detected in the Nobel Biocare system. After 48-hour culture, Astra and Straumann systems displayed the highest cell adhesion at the areas of flank, top, and valley of the implant surface. Primary cells also reached confluence on the valley, but significantly less in the 3i system. Nobel Biocare showed the least cell adhesion on the flank and valley. Implant systems have distinct differences in surface properties, leading to different cell adhesion results. Further in vivo study is needed to study the impact of

  18. ESR studies of high-energy phosphorus-ion implanted synthetic diamond crystals

    Energy Technology Data Exchange (ETDEWEB)

    Isoya, J. [University of Library and Information Science, Tsukuba, Ibaraki (Japan); Kanda, H.; Morita, Y.; Ohshima, T.

    1997-03-01

    Phosphorus is among potential n-type dopants in diamond. High pressure synthetic diamond crystals of type IIa implanted with high energy (9-18 MeV) phosphorus ions have been studied by using electron spin resonance (ESR) technique. The intensity and the linewidth of the ESR signal attributed to the dangling bond of the amorphous phase varied with the implantation dose, suggesting the nature of the amorphization varies with the dose. The ESR signals of point defects have been observed in the low dose as-implanted crystals and in the high dose crystals annealed at high temperature and at high pressure. (author)

  19. The function genomics study

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@ Genomics is a biology term appeared ten years ago, used to describe the researches of genomic mapping, sequencing, and structure analysis, etc. Genomics, the first journal for publishing papers on genomics research was born in 1986. In the past decade, the concept of genomics has been widely accepted by scientists who are engaging in biology research. Meanwhile, the research scope of genomics has been extended continuously, from simple gene mapping and sequencing to function genomics study. To reflect the change, genomics is divided into two parts now, the structure genomics and the function genomics.

  20. Application of laser engineered net shaping (LENS) to manufacture porous and functionally graded structures for load bearing implants.

    Science.gov (United States)

    Bandyopadhyay, Amit; Krishna, B V; Xue, Weichang; Bose, Susmita

    2009-12-01

    Fabrication of net shape load bearing implants with complex anatomical shapes to meet desired mechanical and biological performance is still a challenge. In this article, an overview of our research activities is discussed focusing on application of Laser Engineered Net Shaping (LENS) toward load bearing implants to increase in vivo life time. We have demonstrated that LENS can fabricate net shape, complex metallic implants with designed porosities up to 70 vol.% to reduce stress-shielding. The effective modulus of Ti, NiTi, and other alloys was tailored to suit the modulus of human cortical bone by introducing 12-42 vol.% porosity. In addition, laser processed porous NiTi alloy samples show a 2-4% recoverable strain, a potentially significant result for load bearing implants. To minimize the wear induced osteolysis, unitized structures with functionally graded Co-Cr-Mo coating on porous Ti6Al4V were also made using LENS, which showed high hardness with excellent bone cell-materials interactions. Finally, LENS is also being used to fabricate porous, net shape implants with a functional gradation in porosity characteristics.

  1. A 5-year prospective study of single-tooth replacements supported by the Astra Tech implant: a pilot study

    DEFF Research Database (Denmark)

    Gotfredsen, Klaus

    2004-01-01

    BACKGROUND: Implant-supported single-tooth replacements are an increasingly used method to replace teeth, especially in young patients. Therefore, long-term validation of different treatment modalities with different implant systems is of great importance. PURPOSE: The aim of the present study wa...

  2. A 5-year prospective study of single-tooth replacements supported by the Astra Tech implant: a pilot study

    DEFF Research Database (Denmark)

    Gotfredsen, Klaus

    2004-01-01

    BACKGROUND: Implant-supported single-tooth replacements are an increasingly used method to replace teeth, especially in young patients. Therefore, long-term validation of different treatment modalities with different implant systems is of great importance. PURPOSE: The aim of the present study...

  3. Effect of platform switching on the peri-implant bone: A finite element study

    Science.gov (United States)

    Martínez-González, Amparo; Peiró, Germán; Ródenas, Juan-José; López-Mollá, María-Victoria

    2015-01-01

    Background There exists a relation between the presence and location of the micro-gap and the loss of peri implant bone. Several authors have shown that the treatments based on the use of platform switching result in less peri-implant bone loss and an increased tissue stability. The purpose of this study was to analyse the effect of the platform switching on the distribution of stresses on the peri-implant bone using the finite element method. Material and Methods A realistic 3D full-mandible finite element model representing cortical bone and trabecular bone was used to study the distribution of the stress on the bone induced by an implant of diameter 4.1 mm. Two abutments were modelled. The first one, of diameter 4.1 mm, was used in the reference model to represent a conventional implant. The second one, of diameter 3.2 mm, was used to represent the implant with platform switching. Both models were subjected to axial and oblique masticatory loads. Results The analyses showed that, although no relevant differences can be found for the trabecular bone, the use of platform switching reduces the maximum stress level in the cortical bone by almost 36% with axial loads and by 40% with oblique loads. Conclusions The full 3D Finite Element model, that can be used to investigate the influence of other parameters (implant diameter, connexion type, …) on the biomechanical behaviour of the implant, showed that this stress reduction can be a biomechanical reasons to explain why the platform switching seems to reduce or eliminate crestal bone resorption after the prosthetic restoration. Key words:Dental implant, platform switching, finite element method. PMID:26535094

  4. Study of surface exfoliation on 6H-SiC induced by H2+ implantation

    Science.gov (United States)

    Zhang, L.; Li, B. S.

    2017-03-01

    The effect of lattice damage generated by the H2+-implantation on exfoliation efficiency in 6H-SiC wafers is investigated. 6H-SiC wafers were implanted with 134 keV H2+ ions to ion fluences from 1.5×1016 to 5×1016 H2+ cm-2 and subsequently annealed at temperatures from 973 K to 1373 K. The samples were studied by a combination of optical microscopy and transmission electron microscopy. Only after 1373 K annealing for 15 min, blisters and exfoliation occur on the H2+-implanted sample surface. With increasing the implantation fluences from 1.5×1016 to 3.75×1016 H2+ cm-2, the exfoliation mean size decreases, while the exfoliation density increases. For the highest fluence of 5×1016 H2+ cm-2, seldom exfoliations occur on the sample surface. Microstructure analysis shows that exfoliation efficiency is largely controlled by the H2+-implantation-induced lattice damage. The depth of the microcrack is related to the implantation fluence. The effect of implantation fluence on dislocation loops, platelet nucleation and growth is investigated.

  5. [Effect of periodontal regeneration using collagen-coated synthetic bone implant materials. Histopathological study].

    Science.gov (United States)

    Sugaya, A

    1989-09-01

    Granulated artificial bone implant materials such as hydroxyapatite (HAP) and tricalcium phosphate (TCP) have been frequently used in attempts to restore periodontal tissue lost as a result periodontitis. However, these materials are considered insufficient for the maintenance and stability of granules at sites losing bone, for active bone formation, or for periodontal ligament regeneration. We have now developed a complex consisting of HAP or TCP coated with atelocollagen (which has recently received attention as a biomaterial) and have conducted experiments to determine the effects of this material on the reconstruction of periodontal tissue. Implantations were performed using a HAP-atelocollagen complex, TCP-atelocollagen complex, HAP and TCP at three-wall bone defect sites in experimentally-induced periodontitis in dogs. A control group without the implants was included in the study. Histopathological observations were conducted 2, 4 and 12 weeks after surgery. Compared with the control group, the groups implanted with the complex displayed enhanced maintenance and stability of granules, suppression of epithelial downgrowth, and acceleration of new bone and cementum formation. These results indicate that the implant method using an atelocollagen-coated artificial bone implant material would be useful for periodontal surgical treatment, eliminating some of the disadvantages of conventional implant methods.

  6. MRI assessment of thoracic stent grafts after emergency implantation in multi trauma patients: a feasibility study

    Energy Technology Data Exchange (ETDEWEB)

    Rasche, Volker [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); University Hospital Ulm, University of Ulm, Department of Internal Medicine II, Ulm (Germany); Oberhuber, Alexander; Orend, Karl-Heinz [University Hospital Ulm, Department of Vascular and Thoracic Surgery, Ulm (Germany); Trumpp, Stephan [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); University Hospital Ulm, Department of Vascular and Thoracic Surgery, Ulm (Germany); Bornstedt, Axel; Merkle, Nico; Rottbauer, Wolfgang [University Hospital Ulm, Department of Internal Medicine II, Ulm (Germany); Hoffmann, Martin [University Hospital Ulm, Department of Diagnostic and Interventional Radiology, Ulm (Germany)

    2011-07-15

    To evaluate the feasibility of MRI for static and dynamic assessment of the deployment of thoracic aortic stent grafts after emergency implantation in trauma patients. Twenty patients initially presenting with a rupture of the thoracic aorta were enrolled in this study. All patients underwent thoracic endovascular aortic repair (TEVAR). The deployment of the implanted stent graft was assessed by CTA and MRI, comprising the assessment of the aortic arch with and without contrast agent, and the assessment of the motion of the stent graft over the cardiac cycle. The stent graft geometry and motion over the cardiac cycle were assessable by MRI in all patients. Flow-mediated signal variations in areas of flow acceleration could be well visualised. No statistically significant differences in stent-graft diameters were observed between CT and MRI measurements. MRI appears to be a valuable tool for the assessment of thoracic stent grafts. It shows similar performance in the accurate assessment of stent-graft dimensions to the current gold standard CTA. Its capability of providing additional functional information and the lack of ionising radiation and nephrotoxic contrast agents may make MRI a valuable tool for monitoring patients after TEVAR. (orig.)

  7. Electrical Activation Studies of Ion Implanted Gallium Nitride

    Science.gov (United States)

    2001-11-20

    Amplifier Electromagnet Controller Lakeshore DRC -91CA Temperature Controller 706 Scanner 196 Digital Multimeter 220 Current Source 617 Electrometer...complete list of publications resulting from this doctoral research. The list is divided into three sections: journal articles, refereed conference...2001. Refereed Conference Proceedings: “Optical Characterization of Mg- and Si-Implanted GaN,” Fellows J., Yeo Y.K., Hengehold R., and Krasnobaev

  8. Morphogenesis of the peri-implant mucosa: an experimental study in dogs.

    Science.gov (United States)

    Berglundh, Tord; Abrahamsson, Ingemar; Welander, Maria; Lang, Niklaus P; Lindhe, Jan

    2007-02-01

    The objective of the present experiment was to study the morphogenesis of the mucosal attachment to implants made of c.p. titanium. All mandibular premolars were extracted in 20 Labrador dogs. After a healing period of 3 months, four implants (ITI Dental Implant System) were placed in the right and left sides of the mandible. A non-submerged implant installation technique was used and the mucosal tissues were secured to the conical marginal portion of the implants with interrupted sutures. The sutures were removed after 2 weeks and a plaque control program including daily cleaning of the remaining teeth and the implants was initiated. The animals were sacrificed and biopsies were obtained at various intervals to provide healing periods extending from Day 0 (2 h) to 12 weeks. The mandibles were removed and placed in the fixative. The implant sites were dissected using a diamond saw and processed for histological analysis. Large numbers of neutrophils infiltrated and degraded the coagulum that occupied the compartment between the mucosa and the implant during the initial phase of healing. At 2 weeks after surgery, fibroblasts were the dominating cell population in the connective tissue interface but at 4 weeks the density of fibroblasts had decreased. Furthermore, the first signs of epithelial proliferation were observed in specimens representing 1-2 weeks of healing and a mature barrier epithelium occurred after 6-8 weeks of healing. The collagen fibers of the mucosa were organized after 4-6 weeks of healing. It is suggested that the soft-tissue attachment to implants placed using a non-submerged installation procedure is properly established after several weeks following surgery.

  9. High resolution Laplace DLTS studies of defects in ion-implanted silicon

    Energy Technology Data Exchange (ETDEWEB)

    Evans-Freeman, J.H. E-mail: j.evans-freeman@umist.ac.uk; Abdelgader, N.; Kan, P.Y.Y.; Peaker, A.R

    2002-01-01

    We have used high resolution Laplace deep level transient spectroscopy (LDLTS) to investigate defects in n-type silicon caused by implantation of Si, Ge or Er with doses of the order of 1x10{sup 9} cm{sup -2}. These are compared with defects created in proton irradiated n-type silicon. Unlike the simple proton irradiated case, LDLTS spectra of ion implanted silicon show that there are many emission rates associated with defects with energies in the region of E{sub c}-400 meV. We have carried out annealing studies and Laplace DLTS depth profiling and show that the complex spectra measured from a region less than half way through the implant simplify as the profile is moved through the implant and towards the tail. Annealing studies show that these defects survive an anneal that should remove the E-centre.

  10. Speech recognition in noise as a function of the number of spectral channels : Comparison of acoustic hearing and cochlear implants

    NARCIS (Netherlands)

    Friesen, LM; Shannon, RV; Baskent, D; Wang, YB

    Speech recognition was measured as a function of spectral resolution (number of spectral channels) and speech-to-noise ratio in normal-hearing (NH) and cochlear-implant (CI) listeners. Vowel, consonant, word, and sentence recognition were measured in five normal -hearing listeners, ten listeners

  11. Histopathological analysis of pre-implantation donor kidney biopsies: association with graft survival and function in one year post-transplantation

    Directory of Open Access Journals (Sweden)

    Karla Lais Pêgas

    2014-04-01

    Full Text Available Introduction: Pre-implantation kidney biopsy is a decision-making tool when considering the use of grafts from deceased donors with expanded criteria, implanting one or two kidneys and comparing this to post-transplantation biopsies. The role of histopathological alterations in kidney compartments as a prognostic factor in graft survival and function has had conflicting results. Objective: This study evaluated the prevalence of chronic alterations in pre-implant biopsies of kidney grafts and the association of findings with graft function and survival in one year post-transplant. Methods: 110 biopsies were analyzed between 2006 and 2009 at Santa Casa de Porto Alegre, including live donors, ideal deceased donors and those with expanded criteria. The score was computed according to criteria suggested by Remuzzi. The glomerular filtration rate (GFR was calculated using the abbreviated MDRD formula. Results: No statistical difference was found in the survival of donors stratified according to Remuzzi criteria. The GFR was significantly associated with the total scores in the groups with mild and moderate alterations, and in the kidney compartments alone, by univariate analysis. The multivariate model found an association with the presence of arteriosclerosis, glomerulosclerosis, acute rejection and delayed graft function. Conclusion: Pre-transplant chronic kidney alterations did not influence the post-transplantation one-year graft survival, but arteriosclerosis and glomerulosclerosis is predictive of a worse GFR. Delayed graft function and acute rejection are independent prognostic factors.

  12. Cochlear Implantation through the Middle Fossa Approach: A Review of Related Temporal Bone Studies and Reported Cases.

    Science.gov (United States)

    Lesser, Juan Carlos Cisneros; Brito Neto, Rubens Vuono de; Martins, Graziela de Souza Queiroz; Bento, Ricardo Ferreira

    2017-01-01

    Introduction Middle fossa approach has been suggested as an alternative for patients in whom other routes of electrode insertion are contraindicated. Even though there are temporal bone studies about the feasibility of introducing the cochlear implant through the middle fossa, until now, very few studies have described results when cochlear implant surgery is done through this approach. Objective The objective of this study is to review a series of temporal bone studies related to cochlear implantation through the middle fossa and the results obtained by different surgical groups after cochlear implantation through this approach. Data Sources PubMed, MD consult and Ovid-SP databases. Data Synthesis A total of 8 human cadaveric temporal bone studies and 6 studies reporting cochlear implant surgery through the middle fossa approach met the inclusion criteria. Temporal bone studies show that it is feasible to perform cochlear implantation through this route. So far, only two surgical groups have performed cochlear implantation through the middle fossa with a total of 15 implanted patients. One group entered the cochlea in the most upper part of the basal turn, inserting the implant in the direction of the middle and apical turns; meanwhile, the other group inserted the implant in the apical turn directed in a retrograde fashion to the middle and basal turns. Results obtained in both groups were similar. Conclusions The middle fossa approach is a good alternative for cochlear implantation when other routes of electrode insertion are contraindicated.

  13. Pilot Study of Association of Bacteria on Breast Implants with Capsular Contracture▿

    Science.gov (United States)

    Del Pozo, Jose L.; Tran, Nho V.; Petty, Paul M.; Johnson, Craig H.; Walsh, Molly F.; Bite, Uldis; Clay, Ricky P.; Mandrekar, Jayawant N.; Piper, Kerryl E.; Steckelberg, James M.; Patel, Robin

    2009-01-01

    Capsular contracture is the most common and frustrating complication in women who have undergone breast implantation. Its cause and, accordingly, treatment and prevention remain to be elucidated fully. The aim of this prospective observational pilot study was to test the hypothesis that the presence of bacteria on breast implants is associated with capsular contracture. We prospectively studied consecutive patients who underwent breast implant removal for reasons other than overt infection at the Mayo Clinic from February through September 2008. Removed breast implants were processed using a vortexing/sonication procedure and then subjected to semiquantitative culture. Twenty-seven of the 45 implants collected were removed due to significant capsular contracture, among which 9 (33%) had ≥20 CFU bacteria/10 ml sonicate fluid; 18 were removed for reasons other than significant capsular contracture, among which 1 (5%) had ≥20 CFU/10 ml sonicate fluid (P = 0.034). Propionibacterium species, coagulase-negative staphylococci, and Corynebacterium species were the microorganisms isolated. The results of this study demonstrate that there is a significant association between capsular contracture and the presence of bacteria on the implant. The role of these bacteria in the pathogenesis of capsular contracture deserves further study. PMID:19261794

  14. Coating titanium implants with bioglass and with hydroxyapatite : A comparative study in sheep

    OpenAIRE

    Lopez-Sastre, A.; Gonzalo-Orden, J.M.; Altónaga, J. A. R.; Altónaga, J. R.; Orden, M. A.

    1998-01-01

    This study compares the osteointegration of titanium implants coated with bioglass (Biovetro GSB formula) and with hydroxyapatite (HAP). Twenty-four bioglass-coated and 24 HAP-coated cylinders were implanted in the femoral diaphyses of sheep, and examined after 2, 4, 6, 8, 12, and 16 weeks. The HAP coating gave a stronger and earlier fixation to the bone than did bioglass. Bioglass formed a tissue interface which showed a macrophage reaction with little new bone formation activity. In contras...

  15. Influence of splinting materials (auto vs. photopolymerizing) on implant impression accuracy: an in vitro study

    OpenAIRE

    Braz, Luís Miguel Baptista

    2016-01-01

    Tese de mestrado, Medicina Dentária, Universidade de Lisboa, Faculdade de Medicina Dentária, 2016 Purpose: The aim of the present study was to evaluate if there was any significant difference in accuracy between multiple-unit dental implant casts obtained from splinted direct impression techniques using 2 splinting materials by comparing the casts to the reference models. The null hypothesis tested was that the accuracy of implant-impressions was not affected regardless of the splinting ma...

  16. Luminescence studies on green emitting InGaN/GaN MQWs implanted with nitrogen

    OpenAIRE

    2015-01-01

    We studied the optical properties of metalorganic chemical vapour deposited (MOCVD) InGaN/GaN multiple quantum wells (MQW) subjected to nitrogen (N) implantation and post-growth annealing treatments. The optical characterization was carried out by means of temperature and excitation density-dependent steady state photoluminescence (PL) spectroscopy, supplemented by room temperature PL excitation (PLE) and PL lifetime (PLL) measurements. The as-grown and as-implanted samples were found to exhi...

  17. Direction-dependent RBS channelling studies in ion implanted LiNbO3

    Science.gov (United States)

    Wendler, E.; Becker, G.; Rensberg, J.; Schmidt, E.; Wolf, S.; Wesch, W.

    2016-07-01

    Damage formation in ion implanted LiNbO3 was studied by Rutherford backscattering spectrometry (RBS) along various directions of the LiNbO3 crystal. From the results obtained it can be unambiguously concluded that Nb atoms being displaced during ion implantation preferably occupy the free octahedron sites of the LiNbO3 lattice structure and most likely also form NbLi antisite defects.

  18. Direction-dependent RBS channelling studies in ion implanted LiNbO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Wendler, E., E-mail: elke.wendler@uni-jena.de; Becker, G.; Rensberg, J.; Schmidt, E.; Wolf, S.; Wesch, W.

    2016-07-15

    Damage formation in ion implanted LiNbO{sub 3} was studied by Rutherford backscattering spectrometry (RBS) along various directions of the LiNbO{sub 3} crystal. From the results obtained it can be unambiguously concluded that Nb atoms being displaced during ion implantation preferably occupy the free octahedron sites of the LiNbO{sub 3} lattice structure and most likely also form Nb{sub Li} antisite defects.

  19. Acute Putrescine Supplementation with Schwann Cell Implantation Improves Sensory and Serotonergic Axon Growth and Functional Recovery in Spinal Cord Injured Rats.

    Science.gov (United States)

    Iorgulescu, J Bryan; Patel, Samik P; Louro, Jack; Andrade, Christian M; Sanchez, Andre R; Pearse, Damien D

    2015-01-01

    Schwann cell (SC) transplantation exhibits significant potential for spinal cord injury (SCI) repair and its use as a therapeutic modality has now progressed to clinical trials for subacute and chronic human SCI. Although SC implants provide a receptive environment for axonal regrowth and support functional recovery in a number of experimental SCI models, axonal regeneration is largely limited to local systems and the behavioral improvements are modest without additional combinatory approaches. In the current study we investigated whether the concurrent delivery of the polyamine putrescine, started either 30 min or 1 week after SCI, could enhance the efficacy of SCs when implanted subacutely (1 week after injury) into the contused rat spinal cord. Polyamines are ubiquitous organic cations that play an important role in the regulation of the cell cycle, cell division, cytoskeletal organization, and cell differentiation. We show that the combination of putrescine with SCs provides a significant increase in implant size, an enhancement in axonal (sensory and serotonergic) sparing and/or growth, and improved open field locomotion after SCI, as compared to SC implantation alone. These findings demonstrate that polyamine supplementation can augment the effectiveness of SCs when used as a therapeutic approach for subacute SCI repair.

  20. Evaluation of the clinical efficacy of Gonazon implants in the treatment of reproductive pathologies, behavioral problems, and suppression of reproductive function in the male dog.

    Science.gov (United States)

    Goericke-Pesch, S; Wilhelm, E; Ludwig, C; Desmoulins, P O; Driancourt, M A; Hoffmann, B

    2010-04-15

    Efficacy of a slow-release gonadotropin-releasing hormone (GnRH)-agonist implant (Gonazon) was assessed in 53 male dogs presented with benign prostatic hyperplasia (BPH), hypersexuality, aggressive behavior (either alone or in combination), excessive micturition, or to suppress fertility. Changes in testosterone (T) and estradiol (E2) concentrations and size of testes and prostate were monitored on Weeks 0, +8, and +26 after implantation. Additional measurements during and after this period were performed in 35 dogs. Clinical signs were assessed by the owners. All implants except one were retained throughout the study. Full downregulation of testicular function (Tdogs, five dogs showed partial downregulation (T = 0.36 to 0.47 nmol/L), one dog did not respond, and another one displayed a transient downregulation on Week +18. On Week +8, mean T and E2 levels were reduced by 96% and 62%, respectively, and did not further decrease. Full downregulation (T22 mo in most dogs except two. Compared with pretreatment values, mean testicular and prostatic size was reduced (Pdogs with BPH than in healthy ones on Week +8 (PDogs affected with BPH were significantly older (Pdogsdogs; 75% of the cases responded with an improvement. The only minor and possibly treatment-related events observed were a short-lasting exacerbation of clinical signs of BPH (two dogs), increased weight gain (three dogs), and anxiety (three dogs) with one of these dogs developing a blunt coat. These results demonstrate the clinical efficacy and overall safety of the Gonazon implants.

  1. Outcome of surgical treatment of peri-implantitis: results from a 2-year prospective clinical study in humans.

    Science.gov (United States)

    Serino, Giovanni; Turri, Alberto

    2011-11-01

    The aim of the present study was to evaluate the outcome of a surgical procedure based on pocket elimination and bone re-contouring for the treatment of peri-implantitis. The 31 subjects involved in this study presented clinical signs of peri-implantitis at one or more dental implants (i.e. ≥6 mm pockets, bleeding on probing and/or suppuration and radiographic evidence of ≥2 mm bone loss). The patients were treated with a surgical procedure based on pocket elimination and bone re-contouring and plaque control before and following the surgery. At the time of surgery, the amount of bone loss at implants was recorded. Two years following treatment, 15 (48%) subjects had no signs of peri-implant disease; 24 patients (77%) had no implants with a probing pocket depth of ≥6 mm associated with bleeding and/or suppuration following probing. A total of 36 implants (42%) out of the 86 with initial diagnosis of peri-implantitis presented peri-implant disease despite treatment. The proportion of implants that became healthy following treatment was higher for those with minor initial bone loss (2-4 mm bone loss as assessed during surgery) compared with the implants with a bone loss of ≥5 mm (74% vs. 40%). Among the 18 implants with bone loss of ≥7 mm, seven were extracted. Between the 6-month and the 2-year examination, healthy implants following treatment tended to remain stable, while deepening of pockets was observed for those implants with residual pockets. The results of this study indicated that a surgical procedure based on pocket elimination and bone re-contouring and plaque control before and following surgery was an effective therapy for treatment of peri-implantitis for the majority of subjects and implants. However, complete disease resolution at the site level seems to depend on the initial bone loss at implants. Implants with no signs of peri-implantitis following treatment tended to remain healthy during the 2-year period, while a tendency for disease

  2. 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.

  3. Dental Implants and General Dental Practitioners of Nepal: A study of existing knowledge and need for further education

    Directory of Open Access Journals (Sweden)

    Bhageshwar Dhami

    2017-03-01

    Full Text Available Background & Objectives: The use of dental implants in partially or completely edentulous patients has proved effective and an accepted treatment modality with predictable long-term success. Dental implants are becoming a popular choice for replacing the missing teeth because of increased awareness about implants both in dentists and patients. The objective of the study was to assess the basic knowledge and education about dental implants among general dental practitioners (GDPs of Nepal.Materials & Methods:  A cross sectional questionnaire was carried out among 110 GDPs which consist of twenty questions that were divided into three categories; first with some basic knowledge in implant dentistry, second with clinical knowledge of dental implants and third with dental implant education and training.Results: Out of 110 GDPs, 72.7% had basic knowledge about implant dentistry and 65.5% were not aware about advance surgical procedures like sinus lift and guided bone regeneration. All the GDPs were positive regarding more training and education in dental implants and 95.5% of them would like to incorporate dental implant treatment in their practice in future. Conclusion: GDPs should have adequate knowledge and training of dental implants which can be incorporated at undergraduate or post doctoral level so that they are skilled to provide quality dental implant therapy to their patients confidently.

  4. Anchorage of titanium implants with different surface characteristics: an experimental study in rabbits

    DEFF Research Database (Denmark)

    Gotfredsen, K; Berglundh, T; Lindhe, J

    2000-01-01

    ) TiO2-blasted with particles of grain size 10 to 53 microns; (3) TiO2-blasted, grain size 63 to 90 microns; (4) TiO2-blasted, grain size 90 to 125 microns; (5) titanium plasma-sprayed (TPS). The surface topography was determined by the use of an optical instrument. Twelve rabbits, divided into two...... in group B were 9 and 12 weeks. The tibiae were removed, and each implant site was dissected, fixed, and embedded in light-curing resin. Ground sections were made, and the peri-implant bone was analyzed using fluorescence and light microscopy. RESULTS: The turned implants had the lowest Sa and Sy values......: The present study demonstrated that a clear relation exists between surface roughness, described in Sa values, and implant anchorage assessed by RMT measurements. The anchorage appeared to increase with the maturation of bone tissue during healing....

  5. Aesthetic perception of single implants placed in the anterior zone. A cross-sectional study

    Science.gov (United States)

    Burgueño-Barris, Genís; Cortés-Acha, Berta; Valmaseda-Castellón, Eduard

    2016-01-01

    Background Several aesthetic indexes have been described to assess implant aesthetics. The aim of this study was to compare the aesthetic assessment made by dental professionals and students of single-tooth implants placed in the upper incisors. Material and Methods A cross-sectional survey study using a subjective questionnaire to assess the aesthetics in 3 implant supported single-tooth cases in the anterior maxilla was performed. The interviewed subjects were divided into 4 groups: dentists with experience in implant treatment, dentists without experience in implants and 3rd and 5th year dental students. The questionnaire consisted of 2 visual analogue scales (VAS) to evaluate aesthetics, the pink esthetic score (PES), the white esthetic score (WES) and the simplified papilla index (PI). Results One-hundred dentists and one-hundred dental students filled the aesthetic assessment questionnaire. The results showed that the subjects were more critical than reference values, specially concerning prosthetic issues. The differences between groups were more obvious in the case with the best result. On the other hand, few differences were detected in the remaining cases. Regarding soft tissue and crown features, experienced dentists in implant dentistry were the most demanding. Cronbach’s Alpha showed values ≥ 0,8 in the questionnaire in every case, which indicates an adequate reliability. Conclusions Dentists and dental students have different opinions when assessing aesthetics of single tooth implant supported cases. Experience and area of expertise seem to influence the evaluation of aesthetics in the anterior region. Key words:Dental implant, anterior area, aesthetics. PMID:27031072

  6. Design and health care: a study of virtual design and direct metal lasersintering of titanium alloy for the production of customized facial implants

    Directory of Open Access Journals (Sweden)

    Wilson Kindlein Junior

    2009-11-01

    Full Text Available The increase in life expectancy and a great number ofaccidents lead to higher demand for medical products,including corrective implants. Patients with tumors or traumas need to replace injured areas in order to restore their aesthetic and structural function. Currently, the available craniofacial implants present a standard geometry and seldom generate satisfactory results. Customized implants, on theother hand, are designed to conform exactly to individual patient’s anatomy. This way, the use of customized implantscan show beneficial effects to the patient and the surgicalteam. In this study, the design and manufacturing of customized implant prior to surgery were described. Implant shape and functional requirements were established by digitaldata based on CT-scans and mirroring operations. The designprocess of customized mandible prosthesis is illustrated as well as its manufacturing process (direct metal laser sinteringand quality control. Laser sintering process and its constraints for the production of customized implants in titanium alloy(Ti-6Al-4V with complex geometry and internal structures are reported.

  7. Return of function after spinal cord implantation of avulsed spinal nerve roots.

    Science.gov (United States)

    Carlstedt, T; Grane, P; Hallin, R G; Norén, G

    1995-11-18

    Avulsion of nerve roots from the spinal cord is widely regarded as an untreatable injury. However, a series of experiments in animals has shown that, if continuity is restored between spinal cord and ventral roots, axons from spinal motor neurons can regrow into the peripheral nerves with recovery of motor function. These observations were applied in the treatment of a man with avulsion of the 6th cervical (C6) to 1st thoracic roots due to brachial plexus injury. Two ventral roots were implanted into the spinal cord through slits in the pia mater, C6 directly and C7 via sural nerve grafts. Voluntary activity in proximal arm muscles was detected electromyographically after nine months and clinically after one year. After three years the patient had voluntary activity (with some co-contraction) in the deltoid, biceps, and triceps muscles. To determine whether the improvement was due to spontaneous recovery from C5, the C5 root was blocked pharmacologically, and the results indicated that the repaired roots were contributing substantially to motor function. Repair of spinal nerve roots deserves further exploration in management of brachial plexus injury.

  8. Study on surgical approaches and electrode implantation of oculomotor nerve and inferior obliquus in beagle dogs.

    Science.gov (United States)

    Zhu, Ning-Xi; Meng, You-Qiang; Feng, Bao-Hui; Wang, Xu-Hui; Li, Xin-Yuan; Yang, Min; Zhu, Shu-Gan; Li, Shi-Ting

    2009-03-01

    To study the surgical anatomy and approaches of intracranial oculomotor nerve (OMN) and inferior obliquus (IO), and the methods of their electrode implantation in dogs. The research was performed on 30 adult beagle dogs at Shanghai Jiaotong University Medical College, Shanghai, China from November 2007 to August 2008. All animals were subjected to a right transfrontotemperal approach to intracranial OMN, a transconjunctival route to IO, and the neuro-stimulating and recording electrode implantation under general anaesthesia. The OMN was stimulated and the electromyography of IO recorded and analyzed with the Powerlab System. The security and reliability of the implanted electrodes were investigated. The surgical anatomy and approaches of both the OMN from its exit from midbrain to the entrance into cavernous sinus and the IO were described. Moreover, the implantation methods of OMN stimulating electrode and the electromyographic recording electrode of IO were displayed. The implanted electrodes were safe and reliable. Some electrophysiologic data of IO were obtained in the healthy dogs. Also, some perioperative precautions for intracranial and ophthalmic surgical procedures in dog were exhibited. The mortality rate of the dogs was 0%, and no operative complications were observed. With the data provided, these surgical approaches and the methods of electrode implantation offer a choice to construct an animal model for studying various aspects of OMN regeneration.

  9. Patient’s satisfaction after 2-piece inflatable penile prosthesis implantation: An Italian multicentric study

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    Giorgio Gentile

    2016-03-01

    Full Text Available Introduction: Penile prosthesis implant represents a valuable solution for pts with severe erectile dysfunction (ED, non-responders to medical management. The aim of our study was to evaluate the satisfaction of patients (pts after 2-pieces inflatable penile prosthesis (IPP. Aim of the study: to evaluate safety, reliability and post-operative patient’s satisfaction after implantation of two-pieces IPP. Materials and Methods: This retrospective multicentric analysis concerns a group of 42 patients undergone 2-pieces IPP implantation from November 2005 to November 2013, in four Centers of proven experience. As a first step, a detailed review of all clinical reports was performed. Secondly, every patient was asked to fill the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS specifically modified, in order to assess their own satisfaction after surgery and, its impact on patient’s quality of sexual life. Results: 42 pts were evaluated (AMS-Ambicor: 28; Coloplast- Excell: 14; mean age, at time of operation: 60,7 years; mean follow up: 27,6 months; etiology of ED: vascular 23,8%, diabetes 19%, La Peyronie D. 7,1%, consequence of radical prostatectomy 31%, consequence of other pelvic surgery 11,9%, spinal trauma 7%. Mean operative time: 117 ± 58 min, mean postoperative hospital stay 3 ± 1,6 days. Post operative short-term complications: 4 pts (9,5%. Post operative long-term complications: 4 pts (9,5%. Long-term functional results (Questionnaire: 71% of pts (30 reported regular use of the prosthesis, at least 1 time/week, the satisfaction was good in 42% of pts (18, quite good in 33,3% (14, quite bad in 2,4% (1, very bad in 7,1% (3, 6 pts (14,4% didn’t answer. Conclusions: 2 pieces IPP appears to be associated with a low complication rate and good satisfaction of pts especially in the elderly. It also assures satisfactory rates of aesthetics and functional results.

  10. 10-year survival rate and the incidence of peri-implant disease of 374 titanium dental implants with a SLA surface: a prospective cohort study in 177 fully and partially edentulous patients.

    Science.gov (United States)

    van Velzen, Frank J J; Ofec, Ronen; Schulten, Engelbert A J M; Ten Bruggenkate, Christiaan M

    2015-10-01

    This prospective cohort study evaluates the 10-year survival and incidence of peri-implant disease at implant and patient level of sandblasted, large grid, and acid-etched titanium dental implants (Straumann, soft tissue level, SLA surface) in fully and partially edentulous patients. Patients who had dental implant surgery in the period between November 1997 and June 2001, with a follow-up of at least 10 years, were investigated for clinical and radiological examination. Among the 506 inserted dental implants in 250 patients, 10-year data regarding the outcome of implants were available for 374 dental implants in 177 patients. In the current study, peri-implantitis was defined as advanced bone loss (≧1.5 mm. postloading) in combination with bleeding on probing. At 10-year follow-up, only one implant was lost (0.3%) 2 months after implant surgery due to insufficient osseointegration. The average bone loss at 10 year postloading was 0.52 mm. Advanced bone loss at 10-year follow-up was present in 35 dental implants (9.8%). Seven percent of the observed dental implants showed bleeding on probing in combination with advanced bone loss and 4.2% when setting the threshold for advanced bone loss at 2.0 mm. Advanced bone loss without bleeding on probing was present in 2.8% of all implants. In this prospective study, the 10-year survival rate at implant and patient level was 99.7% and 99.4%, respectively. Peri-implantitis was present in 7% of the observed dental implants according to the above-mentioned definition of peri-implantitis. This study shows that SLA implants offer predictable long-term results as support in the treatment of fully and partially edentulous patients. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Evaluation of implant stabilization in tubercular Spondylodiscitis: a prospective study

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    Sharath Kumar Maila

    2015-10-01

    Results: Mechanical failure of the implant was the most commonly encountered complication. Neurological complications included progressive neurologic deterioration, hoarseness of voice, cauda equina syndrome, foot drop. Persistent worsening of pain, DVT and pressure ulcers were the complications encountered that are not specific to a region of spine. Conclusions: Stabilization is not without complications in tubercular spine. But with strict adherence to guidelines the complications can be minimal and are not dismal. [Int J Res Med Sci 2015; 3(10.000: 2647-2653

  12. Modeling study of the failing heart and its interaction with an implantable rotary blood pump.

    Science.gov (United States)

    Ramachandran, Deepa P; Luo, Chuan; Ma, Tony S; Clark, John W

    2011-01-01

    The effectiveness of clinical diagnosis and treatment of heart failure is a direct function of clinical signs that can be measured in a patient within cost and safety constraints. Large-scale mathematical modeling can be a key tool in revealing important, measurable clinical signs of heart failure, furthering medical understanding and development of treatment. In the first part of this study we have created two models of left heart failure--diastolic and systolic, using our human cardiovascular-respiratory system (H-CRS) model, and we present a comparison of the two types with emphasis on novel and differentiating clinical signs, such as tricuspid flow and septal motion. In the event of compromised left ventricular performance, mechanical left ventricular assist devices (LVAD) are often implanted to augment or completely replace the pumping action of the left ventricle (LV). One such type is the implantable rotary blood pump (iRBP). Several design issues related to the iRBP are difficult to study experimentally due to procedure complexity and limitations in animal models of heart failure [2]. Therefore, modeling has become a key tool in iRBP development. In the second part of this study, we have introduced an iRBP model based on [1]-[2] in the systolic failing heart to study the interactions. We consider optimal motor settings for different levels of LV assistance, the effects of the iRBP on the right heart, septum, and pulmonary circulation. Our model results align with those reported in [1]-[2]. Improvement in cardiac output, pulmonary congestion, and heart work are seen with the iRBP. We observe lowered septal assistance to RV and LV ejection with increasing pump speeds, elevating right ventricular (RV) work, reducing LVET, and causing ventricular mechanical dyssynchrony in ejection. These results suggest right heart compromise via the septum's reduced role with the introduction of an iRBP. This work emphasizes the critical role of modeling in heart failure and

  13. Titanium coated with functionalized carbon nanotubes--a promising novel material for biomedical application as an implantable orthopaedic electronic device.

    Science.gov (United States)

    Przekora, Agata; Benko, Aleksandra; Nocun, Marek; Wyrwa, Jan; Blazewicz, Marta; Ginalska, Grazyna

    2014-12-01

    The aim of the study was to fabricate titanium (Ti) material coated with functionalized carbon nanotubes (f-CNTs) that would have potential medical application in orthopaedics as an implantable electronic device. The novel biomedical material (Ti-CNTs-H2O) would possess specific set of properties, such as: electrical conductivity, non-toxicity, and ability to inhibit connective tissue cell growth and proliferation protecting the Ti-CNTs-H2O surface against covering by cells. The novel material was obtained via an electrophoretic deposition of CNTs-H2O on the Ti surface. Then, physicochemical, electrical, and biological properties were evaluated. Electrical property evaluation revealed that a Ti-CNTs-H2O material is highly conductive and X-ray photoelectron spectroscopy analysis demonstrated that there are mainly COOH groups on the Ti-CNTs-H2O surface that are found to inhibit cell growth. Biological properties were assessed using normal human foetal osteoblast cell line (hFOB 1.19). Conducted cytotoxicity tests and live/dead fluorescent staining demonstrated that Ti-CNTs-H2O does not exert toxic effect on hFOB cells. Moreover, fluorescence laser scanning microscope observation demonstrated that Ti-CNTs-H2O surface retards to a great extent cell proliferation. The study resulted in successful fabrication of highly conductive, non-toxic Ti-CNTs-H2O material that possesses ability to inhibit osteoblast proliferation and thus has a great potential as an orthopaedic implantable electronic device. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Children With Cochlear Implants and Their Parents: Relations Between Parenting Style and Children's Social-Emotional Functioning.

    Science.gov (United States)

    Ketelaar, Lizet; Wiefferink, Carin H; Frijns, Johan H M; Rieffe, Carolien

    Parenting a child who has a severe or profound hearing loss can be challenging and at times stressful, and might cause parents to use more adverse parenting styles compared with parents of hearing children. Parenting styles are known to impact children's social-emotional development. Children with a severe to profound hearing loss may be more reliant on their parents in terms of their social-emotional development when compared with their hearing peers who typically have greater opportunities to interact with and learn from others outside their family environment. Identifying the impact which parenting styles pertain on the social-emotional development of children who have cochlear implants (CIs) could help advance these children's well-being. Therefore, the authors compared parenting styles of parents with hearing children and of parents with children who have a CI, and examined the relations between parenting styles and two key aspects of children's social-emotional functioning: emotion regulation and empathy. Ninety-two hearing parents and their children (aged 1 to 5 years old), who were either hearing (n = 46) or had a CI (n = 46), participated in this cross-sectional study. Parents completed questionnaires concerning their parenting styles (i.e., positive, negative and uninvolved), and regarding the extent to which their children expressed negative emotions (i.e., anger and sadness) and empathy. Furthermore, an emotion-regulation task measuring negative emotionality was administered to the children. No differences in reported parenting styles were observed between parents of hearing children and parents of children with a CI. In addition, negative and uninvolved parenting styles were related to higher levels of negative emotionality in both groups of children. No relation was found between positive parenting and children's social-emotional functioning. Hearing status did not moderate these relationships. Language mediated the relationship between parenting

  15. 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.

  16. The importance of psychosexual counselling in the re-establishment of organic and erotic functions after penile prosthesis implantation.

    Science.gov (United States)

    Pisano, F; Falcone, M; Abbona, A; Oderda, M; Soria, F; Peraldo, F; Marson, F; Barale, M; Fiorito, C; Gurioli, A; Frea, B; Gontero, P

    2015-01-01

    Although many studies about penile prosthesis implantation (PPI) have been published so far, only a small amount of them take into account patients and partners outcome in terms of satisfaction and erotic function. The aim of this study is to explore the value of psycosexual counselling in and the sexual and erotic function of penile prosthesis recipients. Thirty patients and their partners were randomised into two groups. In arm A (case group) patients and their partners underwent a multistep psychosexual counselling before and after surgery. In arm B (control group) surgery was performed without the specific psychosexual counselling scheme. Specific questionnaires (International Index of Erectile Function (IIEF) and the Sexual Daydreaming Scale (SDS)) were administered before surgery and 12 months afterwards. Twenty-four months postoperatively patients were asked to complete the Global Assessment Questions (GAQ) and the Erectile Dysfunction Inventory of Treatment Satisfaction (EDITS), while their partners were asked to answer to the EDITS partner's section. Between January 2009 and October 2011, we enrolled 30 patients undergoing PPI in our institution (15 in each arm). Twenty-four months postoperative follow-up is available for all of them. No significant differences between the two groups in terms of baseline questionnaires scores were observed. Mean IIEF score was significantly higher in case group (arm A 68.3, arm B 53.4, P-value<0.001). At 12 months after PPI the improvement of erotic function according to SDS was significantly higher in the study group for both patients and their partners. Improvement in satisfaction rates were confirmed at 24 months, with statistically significant scores for EDITS in arm A patients and partners as compared with arm B. PPI with a pre- and postoperative psychosexual counselling scheme resulted in better postoperative sexual activity and erotic function for both patients and partners than PPI alone.

  17. Implants in fresh extraction sockets: a prospective 5-year follow-up clinical study.

    Science.gov (United States)

    Botticelli, Daniele; Renzi, Antonio; Lindhe, Jan; Berglundh, Tord

    2008-12-01

    The aim of this prospective study was to evaluate the 5-year clinical outcome of the 'immediate implants.' One week after the cementation of the prosthesis, a clinical baseline examination was carried out. Clinical measurements were performed of the following: plaque, mucositis, probing pocket depth, and soft tissue position. The height of the keratinized mucosa was measured at the buccal/lingual aspects. Standardized intra-oral radiographs were taken. The marginal level of bone to implant contact [radiographic (Rx) bone level] was measured, and Rx bone level change over time was evaluated. The clinical/radiographic measurements were repeated on a yearly basis. The subjects were enrolled in a carefully supervised oral hygiene program. It was demonstrated that 'immediate implants' that were loaded after 5-7 months had a high success rate. During the 5-year interval, no implant was lost, and the mean Rx bone level at the implants was maintained or even improved. The plaque and mucositis scores were low (<20%) at baseline and at all re-examinations. Implant sites located adjacent to the teeth showed bone gain during the initial period while sites that were facing edentulous zones lost some bone.

  18. Study of hydrogen implantation-induced blistering in GaSb for potential layer transfer applications

    Science.gov (United States)

    Pathak, Ravi; Dadwal, U.; Singh, R.

    2017-07-01

    GaSb samples were implanted by 100 keV hydrogen ions (H+) at room temperature with fluence values of 1  ×  1017 and 2  ×  1017 ions cm-2. Post-implantation annealing studies revealed that the samples implanted with a fluence of 2  ×  1017 ions cm-2 did not show blistering/exfoliation. For the lower fluence, the samples showed the formation of surface blisters/craters along with the large area exfoliation of the top H-implanted surface. Topographical investigations of the samples were carried out using Nomarski optical microscopy, atomic force microscopy and stylus surface profilometry. The lateral sizes and heights of the blisters varied between 2-5 µm and 5-20 nm respectively. The root mean square roughness of the exfoliated region was about 12 nm while the exfoliation depth was found to be 730 nm. The exfoliation depth in the H-implanted GaSb is close to the damage concentration peak as found from SRIM calculations. The Föppl-von Karman theory of thin plates has been used to understand the effect of internal pressure and stress on the surface blistering. Using the above mentioned implantation and annealing parameters, potential layer transfer of GaSb could be enabled.

  19. Marginal bone-level alterations of loaded zirconia and titanium dental implants: an experimental study in the dog mandible.

    Science.gov (United States)

    Thoma, Daniel S; Benic, Goran I; Muñoz, Fernando; Kohal, Ralf; Sanz Martin, Ignacio; Cantalapiedra, Antonio G; Hämmerle, Christoph H F; Jung, Ronald E

    2016-04-01

    The aim was to test whether or not the marginal bone-level alterations of loaded zirconia implants are similar to the bone-level alterations of a grade 4 titanium one-piece dental implant. In six dogs, all premolars and the first molars were extracted in the mandible. Four months later, three zirconia implants (BPI, VC, ZD) and a control titanium one-piece (STM) implant were randomly placed in each hemimandible and left for transmucosal healing (baseline). Six months later, CAD/CAM crowns were cemented. Sacrifice was scheduled at 6-month postloading. Digital X-rays were taken at implant placement, crowns insertion, and sacrifice. Marginal bone-level alterations were calculated, and intra- and intergroup comparisons performed adjusted by confounding factors. Implants were successfully placed. Until crown insertion, two implants were fractured (one VC, one ZD). At sacrifice, 5 more implants were (partly) fractured (one BPI, four ZD), and one lost osseointegration (VC). No decementation of crowns occurred. All implant systems demonstrated a statistically significant (except VC) loss of marginal bone between baseline and crown insertion ranging from 0.29 mm (VC; P = 0.116) to 0.80 mm (ZD; P = 0.013). The estimated marginal bone loss between baseline and 6 months of loading ranged between 0.19 mm (BPI) and 1.11 mm (VC), being statistically significant for STM and VC only (P implants and control implants (STM vs. BPI P = 0.007; vs. VC P = 0.001; vs. ZD P = 0.011). Zirconia implants were more prone to fracture prior to and after loading with implant-supported crowns compared to titanium implants. Individual differences and variability in the extent of the bone-level changes during the 12-month study period were found between the different implant types and materials. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  20. Surface morphology analysis of dental implants following insertion into bone using scanning electron microscopy: a pilot study.

    Science.gov (United States)

    Deppe, Herbert; Grünberg, Christina; Thomas, Mücke; Sculean, Anton; Benner, Klaus-Ulrich; Bauer, Florian J M

    2015-11-01

    Dental implants have become essential in reconstructive dentistry. Primary healing is determined by the design of their surface. The aim of this pilot study has been to investigate whether the morphology of the sandblasted and acid-etched (SLA(®) ) surface remains unaffected after the insertion process into human bone. Two edentulous-atrophied human jaw specimens were used. Six brand new Straumann Standard RN implants with an SLA(®) surface and having a diameter of 3.3 mm and a length of 12 mm were inserted. Another two implants of the same type, but not inserted into bone, served as a reference. After explantation, the four implants were cleaned in an ultrasonic bath and two were left uncleaned. All eight implants were inspected by SEM for qualitative surface changes. All four implants showed relevant changes of the topography at the apical thread flanks. The non-cleaned implants showed an almost complete coverage of the surface by a honeycomb-like structure, consistent with bone residues. The reference implants showed no changes. The results indicate that, for the osseointegration of dental implants, subtractive modifications of implant surfaces are less important than the reestablishment of the destroyed TiO2 layer. Further studies of other implant surfaces are required to verify the present results. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. The Prosthetic Influence and Biomechanics on Peri-Implant Strain: a Systematic Literature Review of Finite Element Studies

    Directory of Open Access Journals (Sweden)

    Julius Maminskas

    2016-09-01

    Full Text Available Objectives: To systematically review risks of mechanical impact on peri-implant strain and prosthetic influence on stability across finite element studies. Material and Methods: An online literature search was performed on MEDLINE and EMBASE databases published between 2011 and 2016. Following keywords tiered screening and selection of the title, abstract and full-text were performed. Studies of finite element analysis (FEA were considered for inclusion that were written in English and revealed stress concentrations or strain at peri-implant bone level. Results: There were included 20 FEA studies in total. Data were organized according to the following topics: bone layers, type of bone, osseointegration level, bone level, design of implant, diameter and length of implant, implant-abutment connection, type of supra-construction, loading axis, measurement units. The stress or strain at implant-bone contact was measured over all studies and numerical values estimated. Risks of overloading were accented as non-axial loading, misfits, cantilevers and the stability of peri-implant bone was related with the usage of platform switch connection of abutment. Conclusions: Peri-implant area could be affected by non-axial loading, cantilever prosthetic elements, crown/implant ratio, type of implant-abutment connection, misfits, properties of restoration materials and antagonistic tooth. The heterogeneity of finite element analysis studies limits systematization of data. Results of these studies are comparable with other findings of in vitro, in vivo, prospective and retrospective studies.

  2. In vivo tissue distribution and efficacy studies for cyclosporin A loaded nano-decorated subconjunctival implants.

    Science.gov (United States)

    Yavuz, Burçin; Bozdağ Pehlivan, Sibel; Kaffashi, Abbas; Çalamak, Semih; Ulubayram, Kezban; Palaska, Erhan; Çakmak, Hasan Basri; Ünlü, Nurşen

    2016-11-01

    Biodegradable implants are promising drug delivery systems for sustained release ocular drug delivery with the benefits such as minimum systemic side effects, constant drug concentration at the target site and getting cleared without surgical removal. Dry eye syndrome (DES) is a common disease characterized with the changes in ocular epithelia surface and results in inflammatory reaction that might lead to blindness. Cyclosporin A (CsA) is a cyclic peptide that is frequently employed for the treatment of DES and it needs to be applied several times a day in tear drops form. The aim of this study was to evaluate in vivo behavior and efficacy of the developed nano-decorated subconjunctival implant systems for sustained release CsA delivery. Biodegradable Poly-ɛ-caprolactone (PCL) implant or micro-fiber implants containing CsA loaded poly-lactide-co-glycolide (85:15) (PLGA) or PCL nanoparticles were prepared in order to achieve sustained release. Two of the formulations PCL-PLGA-NP-F and PCL-PCL-NP-I were selected for in vivo evaluation based on their in vitro characteristics determined in our previous study. In this study, formulations were implanted to Swiss Albino mice with induced dry eye syndrome to investigate the ocular distribution of CsA following subconjunctival implantation and to evaluate the efficacy. Tissue distribution study indicated that CsA was present in ocular tissues such as cornea, sclera and lens even 90 days after the application and blood CsA levels were found lower than ocular tissues. Efficacy studies also showed that application of CsA-loaded fiber implant formulation resulted in faster recovery based on their staining scores.

  3. COCHLEAR IMPLANTATION PREVALENCE IN ELDERLY

    Directory of Open Access Journals (Sweden)

    A. V. Starokha

    2014-01-01

    Full Text Available Current paper describes an experience of cochlear implantation in elderly. Cochlear implantation has become a widely accepted intervention in the treatment of individuals with severe-to-profound sensorineural hearing loss. Cochlear implants are now accepted as a standard of care to optimize hearing and subsequent speech development in children and adults with deafness. But cochlear implantation affects not only hearing abilities, speech perception and speech production; it also has an outstanding impact on the social life, activities and self-esteem of each patient. The aim of this study was to evaluate the cochlear implantation efficacy in elderly with severe to profound sensorineural hearing loss. There were 5 patients under our observation. Surgery was performed according to traditional posterior tympanotomy and cochleostomy for cochlear implant electrode insertion for all observed patients. The study was conducted in two stages: before speech processor’s activation and 3 months later. Pure tone free field audiometry was performed to each patient to assess the efficiency of cochlear implantation in dynamics. The aim of the study was also to evaluate quality of life in elderly with severe to profound sensorineural hearing loss after unilateral cochlear implantation. Each patient underwent questioning with 36 Item Short Form Health Survey (SF-36. SF-36 is a set of generic, coherent, and easily administered quality-of-life measures. The SF-36 consists of eight scaled scores, which are the weighted sums of the questions in their section. Each scale is directly transformed into a 0-100 scale on the assumption that each question carries equal weight. The eight sections are: physical functioning; physical role functioning; emotional role functioning; vitality; emotional well-being; social role functioning; bodily pain; general health perceptions. Our results demonstrate that cochlear implantation in elderly consistently improved quality of life

  4. Functional cine MRI of the abdomen for the assessment of implanted synthetic mesh in patients after incisional hernia repair: initial results

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, Tanja [Ludwig-Maximilians-University Munich, Department of Clinical Radiology, Munich (Germany); Ludwig-Maximilians-University Munich, Department of Clinical Radiology, Klinikum Innenstadt, Munich (Germany); Ladurner, Roland; Mussack, Thomas [Ludwig-Maximilians-University Munich, Department of Surgery and Traumatology, Klinikum Innenstadt, Munich (Germany); Gangkofer, Alexander; Reiser, Maximilian; Lienemann, Andreas [Ludwig-Maximilians-University Munich, Department of Clinical Radiology, Munich (Germany)

    2007-12-15

    The aim of our study was to develop a method that allows the vizualiation and evaluation of implanted mesh in patients after incisional hernia repair with MRI. Furthermore, we assessed problems typically related with mesh implantation like adhesions and muscular atrophy. We enrolled 28 patients after incisional hernia repair. In 10 patients mesh implantation was done by laparoscopy (expanded polytetrafluoroethylene=ePTFE mesh) and in 18 by laparotomy (polypropylene mesh). Functional MRI was performed on a 1.5-T system in supine position. Sagittal and axial TrueFISP images of the entire abdomen were acquired with the patient repeatedly straining. Evaluation included: correct position and intact fixation of the mesh, furthermore visceral adhesions, recurrent hernia and atrophy of the rectus muscle. The ePTFE mesh was visible in all cases; the polypropylene mesh was not detectable. In seven of the ten ePTFE meshes the fixation was not intact; two recurrent hernias were detected. Twenty of 28 patients had intraabdominal adhesions. In 5 cases mobility of the abdominal wall was reduced, and 16 patients showed an atropy of the rectus muscle. Functional cine MRI is a suitable method for follow-up studies in patients after hernia repair. ePTFE meshes can be visualized directly, and typical complications like intestinal adhesions and abdominal wall dysmotility can be assessed reliably. (orig.)

  5. Digitally planned, immediately loaded dental implants with prefabricated prostheses in the reconstruction of edentulous maxillae: a 1-year prospective, multicenter study.

    Science.gov (United States)

    Johansson, Björn; Friberg, Bertil; Nilson, Hans

    2009-09-01

    The introduction of digital planning programs has made it possible to place dental implants in preplanned positions and being immediately functionally loaded by using prefabricated prostheses. The aim of this multicenter study was to describe the 1-year results of digitally planned, immediately loaded edentulous maxillae. A total of 312 implants (Brånemark System, TiUnite RP, Nobel Biocare, Göteborg, Sweden) in 52 patients from eight Scandinavian clinics were digitally planned, surgically as well as prosthetically, by using the NobelGuide (Nobel Biocare AB, Göteborg, Sweden) and received prefabricated, immediately loaded fixed prosthetic constructions in the maxillae. Individual implant stability was manually tested at 1-year follow-up. All patients received a Procera Implant Bridge (Nobel Biocare AB); however, in two cases, the bridges were reconstructed due to misfit. In five patients, difficulties in getting the surgical guide completely in position, and in five patients, getting the prostheses completely seated, were noted. All but four patients fulfilled the 1-year follow-up. Two implants were lost during the study period, resulting in a cumulative survival rate of 99.4%. The mean marginal bone resorption from implant placement to the 1-year follow-up was 1.3 mm (SD 1.28). More than 2 mm of marginal resorption was noted in 19% of the implants at this instant. The most frequently reported complications during the first year were gingival hyperplasia and prosthesis-related problems (prosthesis screw loosening, occlusal fractures, and occlusal adjustments). The 1-year results in this multicenter are promising regarding implant and bridge stability; however, the study is planned to be running for at least 3 years.

  6. Positron annihilation study of 4H-SiC by Ge{sup +} implantation and subsequent thermal annealing

    Energy Technology Data Exchange (ETDEWEB)

    Yu, R.S., E-mail: yursh@ihep.ac.cn [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China); Maekawa, M.; Kawasuso, A. [Japan Atomic Energy Agency, Advanced Science Research Center, Watanuki 1233, Takasaki, Gunma 370-1292 (Japan); Wang, B.Y.; Wei, L. [Key Laboratory of Nuclear Analysis Techniques, Institute of High Energy Physics, Chinese Academy of Sciences, No. 19 Yuquan Lu, Beijing 100049 (China)

    2012-01-01

    Positron annihilation in 800 keV Ge{sup +} implanted hexagonal SiC was studied by thermal annealing at temperatures ranging from 800 to 1400 Degree-Sign C. The variation in Doppler broadening S values as a function of the incident positron energy suggests a broad distribution in the depth of vacancy defects in the implanted samples. Increasing the annealing temperature triggers the accumulation of vacancies into vacancy clusters. After annealing at 1400 Degree-Sign C, defects in the deep region of SiC are eliminated, and Ge precipitation is believed to appear in the sample at the same time. Though Ge has a much more negative positron affinity than SiC, positron annihilation coincidence Doppler broadening measurement reveals that a preferential trapping of positrons in Ge seems impossible.

  7. Intramyocardial implantation of differentiated rat bone marrow mesenchymal stem cells enhanced by TGF-β1 improves cardiac function in heart failure rats

    Energy Technology Data Exchange (ETDEWEB)

    Lv, Y. [Department of Histology and Embryology, Hebei Medical University, Shijiazhuang, Hebei (China); Liu, B. [Department of Pathology, the First Affiliated Hospital of Hebei North University, Zhangjiakou, Hebei (China); Wang, H.P. [Department of Histology and Embryology, Hebei North University, Zhangjiakou, Hebei (China); Zhang, L. [Department of Histology and Embryology, Hebei Medical University, Shijiazhuang, Hebei (China)

    2016-05-31

    The present study tested the hypotheses that i) transforming growth factor beta 1 (TGF-β1) enhances differentiation of rat bone marrow mesenchymal stem cells (MSCs) towards the cardiomyogenic phenotype and ii) intramyocardial implantation of the TGF-β1-treated MSCs improves cardiac function in heart failure rats. MSCs were treated with different concentrations of TGF-β1 for 72 h, and then morphological characteristics, surface antigens and mRNA expression of several transcription factors were assessed. Intramyocardial implantation of these TGF-β1-treated MSCs to infarcted heart was also investigated. MSCs were initially spindle-shaped with irregular processes. On day 28 after TGF-β1 treatment, MSCs showed fusiform shape, orientating parallel with one another, and were connected with adjoining cells forming myotube-like structures. Immunofluorescence revealed the expression of cardiomyocyte-specific proteins, α-sarcomeric actin and troponin T, in these cells. The mRNA expression of GATA4 and Nkx2.5 genes was slightly increased on day 7, enhanced on day 14 and decreased on day 28 while α-MHC gene was not expressed on day 7, but expressed slightly on day 14 and enhanced on day 28. Transmission electron microscopy showed that the induced cells had myofilaments, z line-like substances, desmosomes, and gap junctions, in contrast with control cells. Furthermore, intramyocardial implantation of TGF-β1-treated MSCs to infarcted heart reduced scar area and increased the number of muscle cells. This structure regeneration was concomitant with the improvement of cardiac function, evidenced by decreased left ventricular end-diastolic pressure, increased left ventricular systolic pressure and increased maximal positive pressure development rate. Taken together, these results indicate that intramyocardial implantation of differentiated MSCs enhanced by TGF-β1 improved cardiac function in heart failure rats.

  8. Wear-reducing Surface Functionalization of Implant Materials Using Ultrashort Laser Pulses

    Science.gov (United States)

    Oldorf, P.; Peters, R.; Reichel, S.; Schulz, A.-P.; Wendlandt, R.

    The aim of the project called "EndoLas" is the development of a reproducible and reliable method for a functionalization of articulating surfaces on hip joint endoprostheses due to a reduction of abrasion and wear by the generation of micro structures using ultrashort laser pulses. On the one hand, the microstructures shall ensure the capture of abraded particles, which cause third-body wear and thereby increase aseptic loosening. On the other hand, the structures shall improve or maintain the tribologically important lubricating film. Thereby, the cavities serve as a reservoir for the body's own synovial fluid. The dry friction, which promotes abrasion and is a part of the mixed friction in the joint, shall therefore be reduced. In experimental setups it was shown, that the abrasive wear can be reduced significantly due to micro-structuring the articulating implant surfaces. To shape the fine and deterministic cavities on the surfaces, an ultra-short pulsed laser, which is integrated in a high-precision, 5-axes micro-machining system, was used. The laser system, based on an Yb:YAG thin-disk regenerative amplifier, has an average output power of 50 W at the fundamental wavelength of 1030 nm, a maximum repetition rate of 400 kHz and a pulse duration of 6 ps. Due to this, a maximum pulse energy of 125 μJ is achievable. Furthermore external second and third harmonic generation enables the usage of wavelengths in the green and violet spectral range.

  9. Stress analysis in platform-switching implants: a 3-dimensional finite element study.

    Science.gov (United States)

    Pellizzer, Eduardo Piza; Verri, Fellippo Ramos; Falcón-Antenucci, Rosse Mary; Júnior, Joel Ferreira Santiago; de Carvalho, Paulo Sérgio Perri; de Moraes, Sandra Lúcia Dantas; Noritomi, Pedro Yoshito

    2012-10-01

    The aim of this study was to evaluate the influence of the platform-switching technique on stress distribution in implant, abutment, and peri-implant tissues, through a 3-dimensional finite element study. Three 3-dimensional mandibular models were fabricated using the SolidWorks 2006 and InVesalius software. Each model was composed of a bone block with one implant 10 mm long and of different diameters (3.75 and 5.00 mm). The UCLA abutments also ranged in diameter from 5.00 mm to 4.1 mm. After obtaining the geometries, the models were transferred to the software FEMAP 10.0 for pre- and postprocessing of finite elements to generate the mesh, loading, and boundary conditions. A total load of 200 N was applied in axial (0°), oblique (45°), and lateral (90°) directions. The models were solved by the software NeiNastran 9.0 and transferred to the software FEMAP 10.0 to obtain the results that were visualized through von Mises and maximum principal stress maps. Model A (implants with 3.75 mm/abutment with 4.1 mm) exhibited the highest area of stress concentration with all loadings (axial, oblique, and lateral) for the implant and the abutment. All models presented the stress areas at the abutment level and at the implant/abutment interface. Models B (implant with 5.0 mm/abutment with 5.0 mm) and C (implant with 5.0 mm/abutment with 4.1 mm) presented minor areas of stress concentration and similar distribution pattern. For the cortical bone, low stress concentration was observed in the peri-implant region for models B and C in comparison to model A. The trabecular bone exhibited low stress that was well distributed in models B and C. Model A presented the highest stress concentration. Model B exhibited better stress distribution. There was no significant difference between the large-diameter implants (models B and C).

  10. THE INFLUENCE OF SURFACE-FREE ENERGY ON SUPRAGINGIVAL AND SUBGINGIVAL PLAQUE MICROBIOLOGY - AN IN-VIVO STUDY ON IMPLANTS

    NARCIS (Netherlands)

    QUIRYNEN, M; VANDERMEI, HC; BOLLEN, CML; VANDENBOSSCHE, LH; DOORNBUSCH, GI; VANSTEENBERGHE, D; BUSSCHER, HJ

    1994-01-01

    THE INFLUENCE OF SURFACE FREE ENERGY on supra- and subgingival plaque microbiology was examined in 9 patients with functional fixed prostheses supported by endosseous titanium implants. Two abutments (trans-mucosal part of the 2 stage implant) were replaced by either a new titanium abutment or a flu

  11. Biomechanical study of the bone tissue with dental implants interaction

    Directory of Open Access Journals (Sweden)

    Navrátil P.

    2011-12-01

    Full Text Available The article deals with the stress-strain analysis of human mandible in the physiological state and after the dental implant application. The evaluation is focused on assessing of the cancellous bone tissue modeling-level. Three cancellous bone model-types are assessed: Non-trabecular model with homogenous isotropic material, nontrabecular model with inhomogeneous material obtained from computer tomography data using CT Data Analysis software, and trabecular model built from mandible section image. Computational modeling was chosen as the most suitable solution method and the solution on two-dimensional level was carried out. The results show that strain is more preferable value than stress in case of evaluation of mechanical response in cancellous bone. The non-trabecular model with CT-obtained material model is not acceptable for stress-strain analysis of the cancellous bone for singularities occurring on interfaces of regions with different values of modulus of elasticity.

  12. Feasibility study for future implantable neural-silicon interface devices.

    Science.gov (United States)

    Al-Armaghany, Allann; Yu, Bo; Mak, Terrence; Tong, Kin-Fai; Sun, Yihe

    2011-01-01

    The emerging neural-silicon interface devices bridge nerve systems with artificial systems and play a key role in neuro-prostheses and neuro-rehabilitation applications. Integrating neural signal collection, processing and transmission on a single device will make clinical applications more practical and feasible. This paper focuses on the wireless antenna part and real-time neural signal analysis part of implantable brain-machine interface (BMI) devices. We propose to use millimeter-wave for wireless connections between different areas of a brain. Various antenna, including microstrip patch, monopole antenna and substrate integrated waveguide antenna are considered for the intra-cortical proximity communication. A Hebbian eigenfilter based method is proposed for multi-channel neuronal spike sorting. Folding and parallel design techniques are employed to explore various structures and make a trade-off between area and power consumption. Field programmable logic arrays (FPGAs) are used to evaluate various structures.

  13. A Study of Implanted and Wearable Body Sensor Networks

    CERN Document Server

    Ullah, Sana; Siddiqui, M Arif; Kwak, Kyung Sup; 10.1007/978-3-540-78582-8_47

    2009-01-01

    Recent advances in intelligent sensors, microelectronics and integrated circuit, system-on-chip design and low power wireless communication introduced the development of miniaturised and autonomous sensor nodes. These tiny sensor nodes can be deployed to develop a proactive Body Sensor Network (BSN). The rapid advancement in ultra low-power RF (radio frequency) technology enables invasive and non-invasive devices to communicate with a remote station. This communication revolutionizes healthcare system by enabling long term health monitoring of a patient and providing real time feedback to the medical experts. In this paper, we present In-body and On-body communication networks with a special focus on the methodologies of wireless communication between implanted medical devices with external monitoring equipment and recent technological growth in both areas. We also discuss open issues and challenges in a BSN.

  14. The use of rapid prototyped implants to simulate knee joint abnormalities for in vitro testing: a validation study with replica implants of the native trochlea.

    Science.gov (United States)

    Van Haver, Annemieke; De Roo, Karel; De Beule, Matthieu; Van Cauter, Sofie; Labey, Luc; De Baets, Patrick; Claessens, Tom; Verdonk, Peter

    2014-08-01

    To investigate the biomechanical effect of skeletal knee joint abnormalities, the authors propose to implant pathologically shaped rapid prototyped implants in cadaver knee specimens. This new method was validated by replacing the native trochlea by a replica implant on four cadaver knees with the aid of cadaver-specific guiding instruments. The accuracy of the guiding instruments was assessed by measuring the rotational errors of the cutting planes (on average 3.01° in extension and 1.18° in external/internal rotation). During a squat and open chain simulation, the patella showed small differences in its articulation with the native trochlea and the replica trochlea, which could partially be explained by the rotational errors of the implants. This study concludes that this method is valid to investigate the effect of knee joint abnormalities with a replica implant as a control condition to account for the influence of material properties and rotational errors of the implant. © IMechE 2014.

  15. Optimized Axillary Vein Technique versus Subclavian Vein Technique in Cardiovascular Implantable Electronic Device Implantation: A Randomized Controlled Study

    Institute of Scientific and Technical Information of China (English)

    Peng Liu; Yi-Feng Zhou; Peng Yang; Yan-Sha Gao; Gui-Ru Zhao; Shi-Yan Ren; Xian-Lun Li

    2016-01-01

    Background:The conventional venous access for cardiovascular implantable electronic device (CIED) is the subclavian vein,which is often accompanied by high complication rate.The aim of this study was to assess the efficacy and safety of optimized axillary vein technique.Methods:A total of 247 patients undergoing CIED implantation were included and assigned to the axillary vein group or the subclavian vein group randomly.Success rate of puncture and complications in the perioperative period and follow-ups were recorded.Results:The overall success rate (95.7% vs.96.0%) and one-time success rate (68.4% vs.66.1%) of punctures were similar between the two groups.In the subclavian vein group,pneumothorax occurred in three patients.The subclavian gaps of three patients were too tight to allow operation of the electrode lead.In contrast,there were no puncture-associated complications in the axillary vein group.In the patient follow-ups,two patients in the subclavian vein group had subclavian crush syndrome and both of them received lead replacement.The incidence of complications during the perioperative period and follow-ups of the axillary vein group and the subclavian vein group was 1.6% (2/125) and 8.2% (10/122),respectively (x2=5.813,P =0.016).Conclusion:Optimized axillary vein technique may be superior to the conventional subclavian vein technique for CIED lead placement.

  16. Breast Implants

    Science.gov (United States)

    ... Medical Procedures Implants and Prosthetics Breast Implants Breast Implants Share Tweet Linkedin Pin it More sharing options Linkedin Pin it Email Print Breast implants are medical devices that are implanted under the ...

  17. Bone tissue formation adjacent to implants placed in fresh extraction sockets: an experimental study in dogs.

    Science.gov (United States)

    Botticelli, Daniele; Persson, Leif G; Lindhe, Jan; Berglundh, Tord

    2006-08-01

    To study the healing of marginal defects that occurred at implants placed in a healed ridge or in fresh extraction sockets. Six dogs were used. The right side of the mandible was used in the first part of the study. The first, second premolars and first molars were extracted. After 3 months of healing the bone was prepared for implant installation in these premolar and molar sites. The marginal 5 mm of each recipient site was widened with a conical drill. Following implant installation a gap of varying dimension occurred around the titanium rod (artificial defect (A) sites). At this interval the third and fourth premolars were extracted and implants were installed in the distal socket of the two teeth (natural defect (N) sites). The flaps were sutured to allow non-submerged healing. After 2 months, the procedures were repeated in the left side. Two months later the animals were euthanized, and biopsies were obtained and prepared for histological examination. The length of the zone of de novo'bone-to-implant contact' in the defect region was longer at the A sites than at the N sites both at the 2- and the 4-month interval. Further, while after 4 months of healing the marginal bone crest at the A sites was located close to the abutment/fixture junction, at the N sites a marked reduction of the height of the bone crest was documented. Hence, most A site defects became completely resolved whereas healing of the N site defects was incomplete. The process of bone modeling and remodeling at an implant placed in a fresh extraction socket differs from the resolution of marginal defects that may occur following implant installation in a healed ridge.

  18. The perception of stress pattern in young cochlear implanted children: an EEG study

    Directory of Open Access Journals (Sweden)

    Niki Katerina Vavatzanidis

    2016-03-01

    Full Text Available Children with sensorineural hearing loss may (regain hearing with a cochlear implant – a device that transforms sounds into electric pulses and bypasses the dysfunctioning inner ear by stimulating the auditory nerve directly with an electrode array. Many implanted children master the acquisition of spoken language successfully, yet we still have little knowledge of the actual input they receive with the implant and specifically which language sensitive cues they hear. This would be important however, both for understanding the flexibility of the auditory system when presented with stimuli after a (life-long phase of deprivation and for planning therapeutic intervention. In rhythmic languages the general stress pattern conveys important information about word boundaries. Infant language acquisition relies on such cues and can be severely hampered when this information is missing, as seen for dyslexic children and children with specific language impairment. Here we ask whether children with a cochlear implant perceive differences in stress patterns during their language acquisition phase and if they do, whether it is present directly following implant stimulation or if and how much time is needed for the auditory system to adapt to the new sensory modality. We performed a longitudinal ERP study, testing in bimonthly intervals the stress pattern perception of 17 young hearing impaired children (age range: 9-50 months; mean: 22 months during their first 6 months of implant use. An additional session before the implantation served as control baseline. During a session they passively listened to an oddball paradigm featuring the disyllable baba, which was stressed either on the first or second syllable (trochaic vs. iambic stress pattern. A group of age-matched normal hearing children participated as controls.Our results show, that within the first 6 months of implant use the implanted children develop a negative mismatch response for iambic but not

  19. The Impact of Force Transmission on Narrow-Body Dental Implants Made of Commercially Pure Titanium and Titanium Zirconia Alloy with a Conical Implant-Abutment Connection: An Experimental Pilot Study.

    Science.gov (United States)

    Nelson, Katja; Schmelzeisen, Rainer; Taylor, Thomas D; Zabler, Simon; Wiest, Wolfram; Fretwurst, Tobias

    2016-01-01

    The purpose of this study was to visualize the mode and impact of force transmission in narrowdiameter implants with different implant-abutment designs and material properties and to quantify the displacement of the abutment. Narrow-diameter implants from two manufacturers were examined: Astra 3.0-mm-diameter implants (Astra OsseoSpeed TX; n = 2) and Straumann Bone Level implants with a 3.3-mm diameter made of commercially pure titanium (cpTi) Gr. 4 (n = 2) and 3.3-mm TiZr-alloy (n = 2; Bone Level, Straumann) under incremental force application using synchrotron radiography (absorption and inline x-ray phase-contrast) and tomography. During loading (250 N), Astra 3.0 and Bone Level 3.3- mm implants showed a deformation of the outer implant shoulder of 61.75 to 95 μm independent of the implant body material; the inner implant diameter showed a deformation of 71.25 to 109.25 μm. A deformation of the implant shoulder persisted after the removal of the load (range, 42.75 to 104.5 μm). An angulated intrusion of the abutment (maximum, 140 μm) into the implant body during load application was demonstrated; this spatial displacement persisted after removal of the load. This study demonstrated a deformation of the implant shoulder and displacement of the abutment during load application in narrow-diameter implants.

  20. Single-Ion Implantation for the Development of Si-Based MOSFET Devices with Quantum Functionalities

    Directory of Open Access Journals (Sweden)

    Jeffrey C. McCallum

    2012-01-01

    Full Text Available Interest in single-ion implantation is driven in part by research into development of solid-state devices that exhibit quantum behaviour in their electronic or optical characteristics. Here, we provide an overview of international research work on single ion implantation and single ion detection for development of electronic devices for quantum computing. The scope of international research into single ion implantation is presented in the context of our own research in the Centre for Quantum Computation and Communication Technology in Australia. Various single ion detection schemes are presented, and limitations on dopant placement accuracy due to ion straggling are discussed together with pathways for scale-up to multiple quantum devices on the one chip. Possible future directions for ion implantation in quantum computing and communications are also discussed.

  1. Importance of the Roughness and Residual Stresses of Dental Implants on Fatigue and Osseointegration Behavior. In Vivo Study in Rabbits.

    Science.gov (United States)

    Velasco, Eugenio; Monsalve-Guil, Loreto; Jimenez, Alvaro; Ortiz, Iván; Moreno-Muñoz, Jesús; Nuñez-Marquez, Enrique; Pegueroles, Marta; Pérez, Román A; Gil, Francisco Javier

    2016-12-01

    This study focuses on the fatigue behavior and bone-implant attachment for the more usual surfaces of the different CP-titanium dental implants. The implants studied were: as-received (CTR), acid etching (AE), spark-anodization (SA), and with a grit-blasted surface (GB). Residual stresses were determined by means of X-ray diffraction. The fatigue tests were carried out at 37°C on 160 dental implants, and the stress-failure (S-N) curve was determined. The fatigue tests showed that the grit-blasting process improved fatigue life. This is a consequence of the layer of compressive residual stresses that the treatment generates in titanium surfaces. Further, our aim was to assess and compare the short- and midterm bone regenerative potential and mechanical retention of the implants in bone of New Zealand rabbits. The mechanical retention after 4 and 10 weeks of implantation was evaluated with histometric and pull-out tests, respectively, as a measure of the osseointegration of the implants. The results demonstrated that the GB treatment produced microrough that accelerated bone tissue regeneration and increased mechanical retention in the bone bed at short periods of implantation in comparison with all other implants tested. The GB surface produced an improvement in mechanical long-time behavior and improved bone growth. These types of treated implants can have great potential in clinical applications, as evidenced by the outcomes of the current study.

  2. [Modern methods for studying the surface of titanium implants (literature review)].

    Science.gov (United States)

    Suba, Csongor; Velich, Norbert; Vörös, János; Turi, Csaba; Szabó, György

    2004-02-01

    Studies of the coatings found on the surface of titanium implants employed in oral surgery are indispensable for understanding the interactions between the organism and the implant. This paper surveys the theory and practical applicability of the methods most frequently applied to study the surface structure and composition of the material. Detailed accounts are given of various structure investigation methods: scanning electron microscopy, stereo scanning electron microscopy, X-ray diffraction, atomic force microscopy and interference microscopy; and of various composition investigation methods: secondary ion mass spectroscopy, X-ray photoelectron spectroscopy, Auger electron spectroscopy; and also of the corrosion procedures for the study of electrochemical behaviour.

  3. Implant Stability Changes during Early Phase of Healing:A Prospective Cohort Study

    Directory of Open Access Journals (Sweden)

    A. Mesgarzadeh

    2009-06-01

    Full Text Available Objective: To assess the stability changes as a reflection of early healing around roughened-surface implants in human by resonance frequency analysis (RFA.Materials and Methods: One hundred and fifty one ITI SLA implants were placed in either maxilla or mandible of 68 patients. Bone type was classified into 4 groups according to Lekholm and Zarb index. RFA was used for direct implant stability measurement on theday of implant placement, and at 14, 30 and 60 days after placement. Student t-test and ANOVA served for statistical analysis.Results: No early failure occurred. The highest and lowest primary stability was measured in type 1 and type 4 bone, respectively. Implant stability increased over time in types 3 and 4 bone but continuously decreased in type 1 bone during the first 60 days of healing.In type 2 a small decrease in stability was observed until 30 days, and after that the stability increased. The difference between implant stability in type 2 and type 4 bone at eachtime point was highly significant (P0.05. The effect of implant length and diameter on stability at different times was tested with mixed model ANOVA, and no significant difference among groups was observed (P>0.05Conclusion: The present study demonstrated that the pattern of stability changes was different among various bone types. With regard to primary stability and pattern of stability changes in types 2 and 3 bone, immediate and early loading protocols can be recommended in these two bone types, respectively.

  4. Maxillary reconstruction to enable implant insertion: a retrospective study of 181 patients

    Directory of Open Access Journals (Sweden)

    Carneiro José Mario

    2008-12-01

    Full Text Available Abstract Background The purpose of the present study was to evaluate different types of maxillary pre-prosthetic surgery using autogenous bone graft and suggest a guideline for maxillary reconstruction to place implant. Methods 181 patients (125 females and 56 males, age range from 16 to 76 years old, were operated at the Maxillo-Facial Service of the Lille's 2 Universitary Hospital Center (Chairman Pr Joël Ferri. Different techniques were used, but always with autogenous bone grafting. 21 patients underwent a Lefort 1 procedure, 139 underwent sinus graft with or without vestibular onlay graft and 21 underwent onlay graft. This surgical procedure was made to allow the insertion of 685 implants. Results The patients were evaluated by clinical and radiological assessment. In the cases of Lefort 1, the rate of successful osteointegration was higher when the implants were placed in the second part of a two stages procedure: 92%, against 81% for one stage. In cases of sinus lift procedure, the rate of implant success was 98%. The infection rate was 3.5%. There was no significant resorption and the type of prosthesis used was a denture retained by a bar or fixed bridge. In cases of onlay graft, the implant insertion success was 97% and there was no infection. The amount of resorption was more significant in the pre-maxilla than in the other areas and the type of prosthesis used was fixed dentures. Conclusion These observations demonstrate that: the aetiology of the bone defect indicate the type and number of the surgical procedures to re-established good jaws relationship and give the bone conditions to implant insertion successful. Clinical Relevance A guideline for surgical decision in the maxillary reconstruction for oral rehabilitation by implants may help to prevent failures of osseous resorption disorders and to foresee the investment of the bone in quality and necessary quantity.

  5. STUDY OF ADVANTAGES AND DISADVANTAGES OF TOTALLY IMPLANTABLE VENOUS ACCESS DEVICE

    Directory of Open Access Journals (Sweden)

    J. Ahmadi

    2006-07-01

    Full Text Available Totally implantable venous access devices (TIVAD or implantable catheter ports are devices which can be implanted subcutaneously. They enable prolonged and repeated access to the vascular system, into the peritoneal cavity or intravertebral space. This device is particularly useful for repeated medical injection, for blood sampling or transfusion of blood and blood derivatives and for total parenteral nutrition (TPN. Although many patients benefit from the insertion of TIVAD without any secondary effects, any surgical implantation can nevertheless lead to complications. ‎In this study, we investigated the advantages and disadvantages of TIVAD catheter in pediatric age group. A total of 94 cases, 2 to 14 years old, were included in our study. We implanted TIVAD in these patients for chemotherapy in 83 cases (88.29%, for prolonged TPN in 6 cases (6.38%, for corticosteroid and antibiotic therapy after ‎Kasai operation in 2 cases (2.12%, for intermittent IV therapy in 2 cases (2.12% and for need to partial parenteral nutrition in 1 case (1.06%. Out of 94 cases, 14 cases (15% had some kind of complications and 80 cases (85% had no complication. There was no mortality. Most patients and their parents (82 cases, 87.23% were satisfied from TIVAD. ‎It seems that TIVAD can be a useful device for many chronic patients who need an IV access for multiple injections.

  6. X-ray photoelectron study of Si{sup +} ion implanted polymers

    Energy Technology Data Exchange (ETDEWEB)

    Tsvetkova, T; Balabanov, S; Bischoff, L; Krastev, V; Stefanov, P; Avramova, I, E-mail: tania_tsvetkova@yahoo.co.u

    2010-11-01

    X-ray photoelectron spectroscopy was used to characterize different polymer materials