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Sample records for carpometacarpal joint implants

  1. Finite element analysis of thumb carpometacarpal joint implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.

    1995-11-01

    The thumb carpometacarpal joint is frequently replaced in women who have developed severe osteoarthritis of the hand. A new, privately developed implant design consists of two components, trapezial and metacarpal, each with a saddle-shaped articulating surface. A three dimensional finite element model of this implant has been developed to analyze stresses on the device. The first simulations using the model involve loading the implant with forces normal to the trapezial component. Preliminary results show contact stress distributions at the particulating surfaces of the implant.

  2. Failed total carpometacarpal joint prosthesis of the thumb

    DEFF Research Database (Denmark)

    Hansen, Torben Bæk; Homilius, Morten

    2010-01-01

    Total joint prosthesis in carpometacarpal joint arthritis of the thumb often fails. Loosening of the implant is often treated by resection arthroplasty, and we reviewed 10 patients, mean age 54 years (range 47-63) who were treated by resection arthroplasty after a failed total joint prosthesis....... The male:female ratio was 1:4 and the mean duration of observation 32 months (range 6-52). In three patients the revised implant was a MOJE uncemented carpometacarpal joint prosthesis and in seven patients an Elektra uncemented one. At follow-up grip strength was reduced to less than 90% of the other hand...... in eight of 10 patients, but the mean Disabilities of the arm, shoulder, and hand (DASH) scores, self-reported pinch-grip-related function, and pain were comparable with our earlier published results with the Elektra carpometacarpal total joint prosthesis....

  3. Divergent dislocation of the ring and little finger carpometacarpal joints--a rare injury pattern.

    LENUS (Irish Health Repository)

    Dillon, John

    2012-02-03

    Hand injuries due to longitudinal forces in the line of the metacarpals demonstrate unusual dislocation patterns. We describe a case of volar intra-articular fracture dislocation of the ring finger carpometacarpal joint in association with a pure dorsal dislocation of the little finger carpometacarpal joint. Open reduction supplemented with Kirschner wire fixation restored normal carpometacarpal joint anatomical relations and achieved an excellent clinical result.

  4. Thumb Carpometacarpal Joint Stabilization in Ehlers-Danlos Syndrome--Case Report.

    Science.gov (United States)

    Breahna, Anca Nicoleta; Meads, Bryce Maurice

    2015-10-01

    We report the case of an 18-years-old patient with thumb carpometacarpal ligament laxity due to Ehlers-Danlos syndrome who was treated with trapezial opening wedge osteotomy combined with volar ligaments reconstruction. Two years postoperatively she is pain free and the thumb carpometacarpal joint is stable. PMID:26388011

  5. Men and women have similarly shaped carpometacarpal joint bones.

    Science.gov (United States)

    Schneider, M T Y; Zhang, J; Crisco, J J; Weiss, A P C; Ladd, A L; Nielsen, P; Besier, T

    2015-09-18

    Characterizing the morphology of the carpometacarpal (CMC) joint bones and how they vary across the population is important for understanding the functional anatomy and pathology of the thumb. The purpose of this paper was to develop a statistical shape model of the trapezium and first metacarpal bones to characterize the size and shape of the whole bones across a cohort of 50. We used this shape model to investigate the effects of sex and age on the size and shape of the CMC joint bones and the articulating surface area of the CMC joint. We hypothesized that women have similar shape trapezium and first metacarpal bones compared to men, following scaling for overall size. We also hypothesized that age would be a significant predictor variable for CMC joint bone changes. CT image data and segmented point clouds of 50 CMC bones from healthy adult men and women were obtained from an ongoing study and used to generate two statistical shape models. Statistical analysis of the principal component weights of both models was performed to investigate morphological sex and age differences. We observed sex differences, but were unable to detect any age differences. Between men and women the only difference in morphology of the trapezia and first metacarpal bones was size. These findings confirm our first hypothesis, and suggest that the women have similarly shaped trapezium and first metacarpal bones compared to men. Furthermore, our results reject our second hypothesis, indicating that age is a poor predictor of CMC joint morphology.

  6. [Systematization of the articular surfaces of the carpometacarpal joints (author's transl)].

    Science.gov (United States)

    el Bacha, A; Maillot, C

    1977-01-01

    A study, done on 100 hands, of the systematization of the articular surfaces of the carpometacarpal joints, clearly delineates the variability of circumference, dimesions, and relief of the articular facets. An attempt to draw general conclusions from this morphological study, in terms of arthrokinetics, leads to an understanding of the nature of the joints and the movements that are performed at this site.

  7. Multiple carpometacarpal dislocations.

    OpenAIRE

    Kumar, A.; Olney, D B

    1994-01-01

    We present a case of dislocations of the carpometacarpal joints without associated fractures. Although carpometacarpal injuries are relatively uncommon, it is rare for multiple carpometacarpal dislocations to occur without associated fractures. The injury is difficult to diagnose because of swelling of the hand. A lateral radiograph of the wrist has been found to be mandatory to its precise diagnosis if suspected. In the case presented here early diagnosis and closed manipulation in the accid...

  8. Volar dislocation of the index carpometacarpal joint in association with a Bennett's fracture of the thumb: a rare injury pattern.

    LENUS (Irish Health Repository)

    Dillon, J P

    2012-02-03

    We describe a case of volar dislocation of the index carpometacarpal (CMC) joint in association with a Bennett\\'s fracture of the thumb following a motorcycle accident. Volar dislocation of the index carpometacarpal joint is an exceedingly rare but easily missed injury, with only a few reported cases in the literature. This report highlights the importance of a true lateral radiograph and close scrutiny of the film to detect this injury. Closed reduction supplemented with Kirschner wire fixation restored normal anatomical relations and achieved an excellent clinical result.

  9. Osteoarthritis of the thumb carpometacarpal joint: Correlation of ultrasound appearances to disability and treatment response

    International Nuclear Information System (INIS)

    Aim: To evaluate grading of thumb carpometacarpal joint (CMCJ) osteoarthritis (OA) using ultrasound, correlating findings with disability and treatment response. Materials and methods: Patients with symptomatic thumb OA attending for ultrasound-guided CMCJ steroid injection and a group of asymptomatic controls were recruited prospectively. Thumb CMCJ ultrasound was graded (osteophytes, joint-space narrowing, capsule size, and measured capsule size), and a Disabilities of the Arm Shoulder and Hand (DASH) questionnaire was completed for each patient. Symptomatic patients then underwent injection with DASH repeated 6 weeks post-treatment. Ultrasound features were correlated with the initial DASH disability score and response as defined by change in DASH 6 weeks after treatment. Results: Thirty-one patients with symptomatic OA and 37 asymptomatic controls were recruited. With the exception of osteophytes (p = 0.017), no statistically significant correlation was demonstrated between severity of ultrasound features and patient disability. However, all features demonstrated statistically significant higher grades in the symptomatic group compared to controls. Ultrasound grading did not have statistical correlation with treatment response. Conclusion: No correlation was found between the majority of ultrasound features and the clinical severity of OA or likely response to treatment. However, these features are significantly more common in the symptomatic population

  10. Ligament reconstruction with tendon interposition arthroplasty for first carpometacarpal joint osteoarthritis

    Institute of Scientific and Technical Information of China (English)

    Yang Yong; Huey Y.Tien; Kannan K.Kumar; Chen Shanlin; Li Zhongzhe; Tian Wen; Tian Guanglei

    2014-01-01

    Background Ligament reconstruction tendon interposition (LRTI) is the most commonly performed surgical procedure for first carpometacarpal joint osteoarthdtis.The purpose of this study was to examine the radiographic and clinical outcomes of LRTI arthroplasty and document the clinical results based on metacarpal subsidence.Methods From January 2008 to January 2011,19 patients (21 thumbs) underwent surgery for thumb carpometacarpal arthritis using ligament reconstruction tendon interposition arthroplasty with flexor carpi radialis (FCR) in Kleinert Kutz Hand Care Center of Louisville University,USA.The follow-up period was an average of 13.9 months.Pain,grip strength,tip pinch strength,range of motion,and radiographic measurements were recorded.Based on first metacarpal subsidence,the cases were classified in to mild,moderate,and severe.Clinical outcomes of the groups were evaluated and compared.Results Grip strength improved from 18.6 kg to 20.5 kg,and tip pinch strength increased from 4.4 kg to 4.5 kg after the surgery.Radial abduction and palmar abduction improved after surgery.Radial abduction increased from 55.7° to 60.6° and palmar abduction improved from 56.7° to 63.5° after the procedure.Visual analogue scores (VAS) were significantly reduced,from 6.6 to 0.5.Compared with the preoperative radiographs the first metacarpal had subsided about 54.6% of the arthroplasty space.The height of arthroplasty space and index of the arthroplasty space significantly decreased from 12.4 mm to 5.6 mm and from 0.27 to 0.12 respectively.Between the various groups (mild,moderate and severe metacarpal subsidence),there was no difference in grip strength,tip pinch strength,thumb range of motion,and VAS.Conclusions Ligament reconstruction tendon interposition arthroplasty resulted in excellent relief of pain and increase in range of motion.However,LRTI cannot maintain the arthroplasty space.Compared with the preoperative radiographs,the metacarpal subsided more than 50

  11. Osteoarthritis of the carpometacarpal joint of the thumb: a new MR imaging technique for the standardized detection of relevant ligamental lesions

    International Nuclear Information System (INIS)

    To assess ligament lesions and subluxations of the carpometacarpal joints of the thumbs (CMC I) of asymptomatic volunteers and of patients with CMC I osteoarthritis using advanced magnetic resonance imaging (MRI). A total of 20 CMC I joints of 14 asymptomatic volunteers (6 x both sides) and 28 CMC I joints of 22 patients (6 x both sides) with symptomatic and X-ray-diagnosed osteoarthritis of CMC I joints were studied. During extension, flexion, abduction and adduction of the thumb, the anterior oblique (AOL), intermetacarpal (IML), posterior oblique (POL) and dorsal radial (DRL) ligaments were evaluated using 3-T MRI on two standard planes, and translation of metacarpal I (MC I) was assessed. The MRI demonstrated that ligament lesions of the AOL and IML are frequent. Isolated rupture of the AOL was found in 6 of 28 (21 %), combined rupture of the AOL + IML in 5 of 28 (18 %) and isolated IML rupture in 4 of 28 (14 %) joints. The patients had a significantly increased dorsal translation of MC I during extension with a median of 6.4 mm vs. 5.4 mm in asymptomatic volunteers (p < 0.05). MRIs of CMC I in two standardized planes frequently show combined ligament ruptures. The dorsal subluxation of MC I, which is increased in patients, correlates with OA severity based on X-ray and can be quantified by MRI. For joint-preserving surgical procedures and for prosthesis implantation of the CMC I, we recommend performing an MRI in two planes of the thumb - extension and abduction - to evaluate the ligaments and dorsal subluxation of MC I. (orig.)

  12. Osteoarthritis of the carpometacarpal joint of the thumb: a new MR imaging technique for the standardized detection of relevant ligamental lesions

    Energy Technology Data Exchange (ETDEWEB)

    Dumont, Clemens [University Medical Center Goettingen, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Georg-August-Universitaet, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Lerzer, Sebastian; Tezval, Mohammad; Stuermer, Klaus Michael [University Medical Center Goettingen, Department of Trauma Surgery, Plastic and Reconstructive Surgery, Goettingen (Germany); Vafa, Morad Ali; Lotz, Joachim [University Medical Center Goettingen, Department of Diagnostic Radiology and Interventional Radiology, Goettingen (Germany); Dechent, Peter [University Medical Center Goettingen, MR-Research in Neurology and Psychiatry, Department of Cognitive Neurology, Goettingen (Germany)

    2014-10-15

    To assess ligament lesions and subluxations of the carpometacarpal joints of the thumbs (CMC I) of asymptomatic volunteers and of patients with CMC I osteoarthritis using advanced magnetic resonance imaging (MRI). A total of 20 CMC I joints of 14 asymptomatic volunteers (6 x both sides) and 28 CMC I joints of 22 patients (6 x both sides) with symptomatic and X-ray-diagnosed osteoarthritis of CMC I joints were studied. During extension, flexion, abduction and adduction of the thumb, the anterior oblique (AOL), intermetacarpal (IML), posterior oblique (POL) and dorsal radial (DRL) ligaments were evaluated using 3-T MRI on two standard planes, and translation of metacarpal I (MC I) was assessed. The MRI demonstrated that ligament lesions of the AOL and IML are frequent. Isolated rupture of the AOL was found in 6 of 28 (21 %), combined rupture of the AOL + IML in 5 of 28 (18 %) and isolated IML rupture in 4 of 28 (14 %) joints. The patients had a significantly increased dorsal translation of MC I during extension with a median of 6.4 mm vs. 5.4 mm in asymptomatic volunteers (p < 0.05). MRIs of CMC I in two standardized planes frequently show combined ligament ruptures. The dorsal subluxation of MC I, which is increased in patients, correlates with OA severity based on X-ray and can be quantified by MRI. For joint-preserving surgical procedures and for prosthesis implantation of the CMC I, we recommend performing an MRI in two planes of the thumb - extension and abduction - to evaluate the ligaments and dorsal subluxation of MC I. (orig.)

  13. Osteoarthritis of the first carpometacarpal joint: a study of radiology and clinical epidemiology:

    DEFF Research Database (Denmark)

    Sonne-Holm, Stig; Jacobsen, J

    2006-01-01

    Epidemiological studies show an increased prevalence of osteoarthritis of the knee and hand with increased body mass index [BMI]. Osteoarthritis of the hip joint is not related to BMI. The connection between obesity and osteoarthritis cannot exclusively be explained by genetic factors or by the a......Epidemiological studies show an increased prevalence of osteoarthritis of the knee and hand with increased body mass index [BMI]. Osteoarthritis of the hip joint is not related to BMI. The connection between obesity and osteoarthritis cannot exclusively be explained by genetic factors...... or by the accumulation of tear and wear. Overweight occurs prior to knee joint degeneration, not as a result of diminished activity due to joint degeneration. Weight control seems to be an influential tool in the prophylaxis of overweight-specific joint degeneration....

  14. Total carpometacarpal joint dislocation combined with trapezium fracture, trapezoid dislocation and hamate fracture

    DEFF Research Database (Denmark)

    Gvozdenovic, R; Vadstrup, Lars Soelberg

    2015-01-01

    Multiple metacarpal dislocations combined with carpal fracture - dislocations are rare injuries. We report a new combination of these injuries where fracture-dislocation of the base of the 1st metacarpal bone occurred simultaneously with a comminuted fracture of the trapezium, dislocation...... of the trapezoid and metacarpal joints (2nd to 5th) and an avulsion fracture of the hamate. This specific carpal injury has not been previously described and our description will contribute to understanding the mechanism of these complex injuries. The injury pattern in the case featured here was multifaceted...... and resulted from rupture of both transverse and longitudinal carpal columns. According to the Garcia-Elias classification of axial carpal disruptions, this particular injury mechanism was a combined axial-radial-ulnar type injury. These injuries are extremely rare and are only sporadically described...

  15. Treatment of thumb carpometacarpal osteoarthritis; quo vadis?

    NARCIS (Netherlands)

    Spaans, AJ

    2016-01-01

    The unique prehensile ability of the human hand is largely due to the biomechanical function of its complex first carpometacarpal (CMC1) joint. This makes the thumb the most important digit of the hand. The unique demands placed on the thumb regarding mobility, stability and transmission of force ma

  16. Multiple Volar Carpometacarpal Dislocations with Associated Carpal Tunnel Syndrome: A Case Report

    Directory of Open Access Journals (Sweden)

    C Fletcher

    2015-09-01

    Full Text Available We report a rare injury involving volar fracture dislocations of the second to fifth carpometacarpal dislocations. Carpometacarpal dislocations are usually dorsally displaced and most commonly only involve the fourth and fifth joints. An associated carpal tunnel syndrome adds another dimension to the complexity and rarity of the injury in this index case. A high index of clinical suspicion and subsequent emergent management is of utmost importance to treat this unusual combination of injuries in order to avoid significant morbidity.

  17. Artrodese do punho com fixação mínima preservando as articulações carpometacarpianas Wrist arthrodesis with minimal internal fixation preserving the carpometacarpal joints

    Directory of Open Access Journals (Sweden)

    Arlindo Gomes Pardini Júnior

    2010-01-01

    structures. In general, the results are very satisfactory, particularly for pain relief, and in the majority of cases, there is considerable functional improvement. Various techniques are described, with different methods of internal fixation, most of which include the carpometacarpal joints (CMJ in the fusion. The objective of this study is to evaluate the results of wrist arthrodesis through a technique which is simpler, more biological, more inexpensive, and does not involve the carpometacarpal joints. METHODS: 15 patients with wrist arthrodesis were evaluated (6 with sequelae of trauma, 4 Rheumatoid Arthritis, 3 Kienbock's grade IV, 1 Preiser and 1 panarthrosis. The technique consisted of the use of an iliac bone plate and internal fixation with Kirschner wires, avoiding the carpometacarpal joints. RESULTS: The evaluation was based on consolidation time (93% in 7 weeks; movements of the fingers and pronosupination; pinch and grasp strength; functional evaluation through the DASH questionnaire, pain and patient satisfaction. In general, the results were similar to those of other, more aggressive techniques, and the non-inclusion of the carpometacarpal joints did not affect the final result. CONCLUSION: wrist arthrodesis with fixation using Kirschner wires and the use of an iliac bone plate, preserving the carpometacarpal joints, gives good or excellent results which are similar to those of other techniques described. However it presents major advantages over other methods: it is less aggressive, less expensive, and does not have the inconvenience and complications associated the use of plates and screws.

  18. A computational method for comparing the behavior and possible failure of prosthetic implants

    Energy Technology Data Exchange (ETDEWEB)

    Nielsen, C.; Hollerbach, K.; Perfect, S.; Underhill, K.

    1995-05-01

    Prosthetic joint implants currently in use exhibit high Realistic computer modeling of prosthetic implants provides an opportunity for orthopedic biomechanics researchers and physicians to understand possible in vivo failure modes, without having to resort to lengthy and costly clinical trials. The research presented here is part of a larger effort to develop realistic models of implanted joint prostheses. The example used here is the thumb carpo-metacarpal (cmc) joint. The work, however, can be applied to any other human joints for which prosthetic implants have been designed. Preliminary results of prosthetic joint loading, without surrounding human tissue (i.e., simulating conditions under which the prosthetic joint has not yet been implanted into the human joint), are presented, based on a three-dimensional, nonlinear finite element analysis of three different joint implant designs.

  19. Implant arthroplasty for the distal radioulnar joint.

    Science.gov (United States)

    Scheker, Luis R

    2008-11-01

    The distal radioulnar joint (DRUJ) is a weight-bearing joint; the ulnar head is frequently excised either totally or partially and in some cases is fused because of degenerative, rheumatoid, or posttraumatic arthritis and treated with a "salvage procedure." The result of these procedures is the inability of those patients to lift even minor weight. Articles about these procedures report the ability to pronate and supinate, but they rarely discuss grip strength or lifting capacity. We present an alternative to the salvage procedures that allows full range of motions as well as the ability to grip and lift weights encountered in daily living, such as a gallon of milk. The Aptis total DRUJ replacement prosthesis (Aptis Medical, Louisville, KY), a bipolar self-stabilizing DRUJ endoprosthesis, restores the forearm function. The technique of implantation is presented here.

  20. Modification of the total first metatarsophalangeal joint implant arthroplasty.

    Science.gov (United States)

    Corrigan, G; Kanat, I O

    1989-01-01

    The Swanson Silastic HP 100 Flexible Hinge Toe Implant (Dow Corning Wright, Arlington Tennessee) displays superior tensile, elongation and tear propagation strength in comparison to other silicone implant materials. It is, however, subject to many factors which may shorten its life-span. One reason for such failure has been attributed to the irregular contour of bone ends created after metatarsophalangeal joint arthroplasty, resulting in abrasion shards and shearing fractures of the implant stems and hinge. Titanium grommets were developed to alleviate this factor. This case report demonstrates a complication subsequent to total first metatarsophalangeal joint implant arthroplasty and the effectiveness of the Swanson Flexible Hinge Toe Joint Grommet. (Dow Corning Wright, Arlington, Tennessee). PMID:2794361

  1. Instrumented knee joint implants: innovations and promising concepts.

    Science.gov (United States)

    Torrão, João N D; Dos Santos, Marco P Soares; Ferreira, Jorge A F

    2015-01-01

    This article focuses on in vivo implementations of instrumented knee implants and recent prototypes with highly innovative potential. An in-depth analysis of the evolution of these systems was conducted, including three architectures developed by two research teams for in vivo operation that were implanted in 13 patients. The specifications of their various subsystems: sensor/transducers, power management, communication and processing/control units are presented, and their features are compared. These systems were designed to measure biomechanical quantities to further assist in rehabilitation and physical therapy, to access proper implant placement and joint function and to help predicting aseptic loosening. Five prototype systems that aim to improve their operation, as well as include new abilities, are also featured. They include technology to assist proper ligament tensioning and ensure self-powering. One can conclude that the concept of instrumented active knee implant seems the most promising trend for improving the outcomes of knee replacements.

  2. The Functional Anatomy of the Carpometacarpal Complex in Anthropoids and Its Implications for the Evolution of the Hominoid Hand.

    Science.gov (United States)

    Selby, Michael S; Simpson, Scott W; Lovejoy, C Owen

    2016-05-01

    Previously, we described several features of the carpometacarpal joints in extant large-bodied apes that are likely adaptations to the functional demands of vertical climbing and suspension. We observed that all hominids, including modern humans and the 4.4-million-year-old hominid Ardipithecus ramidus, lacked these features. Here, we assess the uniqueness of these features in a large sample of monkey, ape, and human hands. These new data provide additional insights into the functional adaptations and evolution of the anthropoid hand. Our survey highlights a series of anatomical adaptations that restrict motion between the second and third metacarpals (MC2 and MC3) and their associated carpals in extant apes, achieved via joint reorganization and novel energy dissipation mechanisms. Their hamate-MC4 and -MC5 joint surface morphologies suggest limited mobility, at least in Pan. Gibbons and spider monkeys have several characters (angled MC3, complex capitate-MC3 joint topography, variably present capitate-MC3 ligaments) that suggest functional convergence in response to suspensory locomotion. Baboons have carpometacarpal morphology suggesting flexion/extension at these joints beyond that observed in most other Old World monkeys, probably as an energy dissipating mechanism minimizing collision forces during terrestrial locomotion. All hominids lack these specializations of the extant great apes, suggesting that vertical climbing was never a central feature of our ancestral locomotor repertoire. Furthermore, the reinforced carpometacarpus of vertically climbing African apes was likely appropriated for knuckle-walking in concert with other novel potential energy dissipating mechanisms. The most parsimonious explanation of the structural similarity of these carpometacarpal specializations in great apes is that they evolved independently. PMID:26916787

  3. Outcome Assessment after Aptis Distal Radioulnar Joint (DRUJ Implant Arthroplasty

    Directory of Open Access Journals (Sweden)

    Amir Reza Kachooei

    2014-09-01

    Full Text Available Background:  Conventional treatments after complicated injuries of the distal radioulnar joint (DRUJ such as Darrach and Kapandji-Sauvé procedures have many drawbacks, which may eventually lead to a painful unstable distal ulna.  The development of DRUJ prosthesis has significantly evolved over the past years. In this study, we assessed the outcome results of patients after DRUJ implant arthroplasty using the Aptis (Scheker prosthesis. Methods: We identified 13 patients with 14 prosthesis during the past 10 years. Patients underwent DRUJ arthroplasty due to persistent symptoms of instability, chronic pain, and stiffness. Records and follow-up visits were reviewed to find the final post-operative symptoms, pain, range of motion, and grip strength with a mean follow-up of 12 months (range: 2-25 months. Also, patients were contacted prospectively by phone in order to  minister the disabilities of the armshoulder and hand (DASH, patient rated wrist evaluation (PRWE, and visual analogue scale (VAS, and to interview regarding satisfaction and progress in daily activities. Eleven patients out of 13 could be reached with a median followup time of 60 months (range: 2 to 102 months.  Results: No patient required removal of the prosthesis. Only two patients underwent secondary surgeries in which both required debridement of the screw tip over the radius. The median DASH score, PRWE score, VAS, and satisfaction were 1.3, 2.5, 0, and 10, respectively. The mean range of flexion, extension, supination, and pronation was 62, 54, 51, and 64, respectively. Conclusions: Distal radioulnar joint injuries are disabling and patients usually undergo one or more salvage surgeries prior to receiving an arthroplasty. The Scheker prosthesis has shown satisfactory results with 100% survival rate in all reports. The constrained design of this prosthesis gives enough stability to prevent painful subluxation.

  4. The biomechanics of a thumb carpometacarpal immobilization splint: design and fitting.

    Science.gov (United States)

    Colditz, J C

    2000-01-01

    Splinting for the common osteoarthritis of the carpometacarpal (CMC) joint of the thumb is infrequently described in the literature, but the few splints that are described include one or both adjacent joints. This paper describes the design and biomechanics of a custom-molded thumb CMC immobilization splint that excludes the thumb metacarpophalangeal and wrist joints. The problem of the imbalance of extrinsic extensor/abductor forces against the intrinsic flexor/adductor forces is described. The accompanying weakening of the thumb CMC capsule allows dorsal shifting of the proximal end of the metacarpal, producing pain. The splint described in this paper 1) prevents motion of the first metacarpal in relation to the other metacarpals, 2) prevents tilting (flexion) of the first metacarpal during pinch, and 3) allows unrestricted thumb metacarpal and wrist joint motion. Attention to detail during construction is required for an accurate pattern, precise positioning of the CMC joint during molding, accurate molding around the first metacarpal, and well-distributed pressure. This design may also be used for protection following thumb CMC arthroplasty or thumb CMC sprain or strain and as a base for thumb metacarpophalangeal and/or interphalangeal mobilization splinting.

  5. Outcome Assessment after Aptis Distal Radioulnar Joint (DRUJ Implant Arthroplasty

    Directory of Open Access Journals (Sweden)

    Amir Reza Kachooei

    2014-09-01

    Distal radioulnar joint injuries are disabling and patients usually undergo one or more salvage surgeries prior to receiving an arthroplasty. The Scheker prosthesis has shown satisfactory results with 100% survival rate in all reports. The constrained design of this prosthesis gives enough stability to prevent painful subluxation.

  6. Acromioclavicular joint reconstruction using the LockDown synthetic implant: a study with cadavers.

    Science.gov (United States)

    Taranu, R; Rushton, P R P; Serrano-Pedraza, I; Holder, L; Wallace, W A; Candal-Couto, J J

    2015-12-01

    Dislocation of the acromioclavicular joint is a relatively common injury and a number of surgical interventions have been described for its treatment. Recently, a synthetic ligament device has become available and been successfully used, however, like other non-native solutions, a compromise must be reached when choosing non-anatomical locations for their placement. This cadaveric study aimed to assess the effect of different clavicular anchorage points for the Lockdown device on the reduction of acromioclavicular joint dislocations, and suggest an optimal location. We also assessed whether further stability is provided using a coracoacromial ligament transfer (a modified Neviaser technique). The acromioclavicular joint was exposed on seven fresh-frozen cadaveric shoulders. The joint was reconstructed using the Lockdown implant using four different clavicular anchorage points and reduction was measured. The coracoacromial ligament was then transferred to the lateral end of the clavicle, and the joint re-assessed. If the Lockdown ligament was secured at the level of the conoid tubercle, the acromioclavicular joint could be reduced anatomically in all cases. If placed medial or 2 cm lateral, the joint was irreducible. If the Lockdown was placed 1 cm lateral to the conoid tubercle, the joint could be reduced with difficulty in four cases. Correct placement of the Lockdown device is crucial to allow anatomical joint reduction. Even when the Lockdown was placed over the conoid tubercle, anterior clavicle displacement remained but this could be controlled using a coracoacromial ligament transfer. PMID:26637681

  7. Hallmarks in the history of orthopaedic implants for trauma and joint replacement.

    Science.gov (United States)

    Markatos, Konstantinos; Tsoucalas, Gregory; Sgantzos, Markos

    2016-08-01

    This manuscript represents an attempt to review orthopaedic implants and reconstructive orthopaedic surgery for lower limbs lesions or trauma mainly in the 20th century. We emphasized on the type of implants, the biomaterials and their evolution, and we also engaged in a special reference for the pioneers of orthopaedic implant surgery and the innovative designers of those implants, in such a way to understand the ways and the stages through which they evolved to their present forms, as well as the scientific principles that affected their design and progress. A correlation between the evolution of implants and several relevant disciplines (biomaterial chemists and engineers, biomechanics) that developed simultaneously with orthopaedic reconstructive joint surgery is present since the first attempts to reconstruct a damaged joint. In the future, further progress is anticipated in the use of biomaterials, more compatible towards human biology, with minimally invasive applications and a perpetually increased life span. This progress depicts a phenomenon directly related to a multilevel, multifactorial and interdisciplinary scientific and technological field with many expectations. PMID:27598960

  8. Effect of Vertical Misfit on Screw Joint Stability of Implant-Supported Crowns

    Science.gov (United States)

    Assunção, Wirley Gonçalves; Delben, Juliana Aparecida; Tabata, Lucas Fernando; Barão, Valentim Adelino Ricardo; Gomes, Érica Alves

    2011-08-01

    The passive fit between prosthesis and implant is a relevant factor for screw joint stability and treatment success. The aim of this study was to evaluate the influence of vertical misfit in abutment-implant interface on preload maintenance of retention screw of implant-supported crowns. The crowns were fabricated with different abutments and veneering materials and divided into 5 groups ( n = 12): Gold UCLA abutments cast in gold alloy veneered with ceramic (Group I) and resin (Group II), UCLA abutments cast in titanium veneered with ceramic (Group III) and resin (Group IV), and zirconia abutments with ceramic veneering (Group V). The crowns were attached to implants by gold retention screws with 35-N cm insertion torque. Specimens were submitted to mechanical cycling up to 106 cycles. Measurements of detorque and vertical misfit in abutment-implant interface were performed before and after mechanical cycling. ANOVA revealed statistically significant difference ( P titanium exhibited the highest misfit values. Pearson correlation test did not demonstrate significant correlation ( P > 0.05) between vertical misfit and detorque value. It was concluded that vertical misfit did not influence torque maintenance and the abutments cast in titanium exhibited the highest misfit values.

  9. Evaluation of predicted knee-joint muscle forces during gait using an instrumented knee implant.

    Science.gov (United States)

    Kim, Hyung J; Fernandez, Justin W; Akbarshahi, Massoud; Walter, Jonathan P; Fregly, Benjamin J; Pandy, Marcus G

    2009-10-01

    Musculoskeletal modeling and optimization theory are often used to determine muscle forces in vivo. However, convincing quantitative evaluation of these predictions has been limited to date. The present study evaluated model predictions of knee muscle forces during walking using in vivo measurements of joint contact loading acquired from an instrumented implant. Joint motion, ground reaction force, and tibial contact force data were recorded simultaneously from a single subject walking at slow, normal, and fast speeds. The body was modeled as an 8-segment, 21-degree-of-freedom articulated linkage, actuated by 58 muscles. Joint moments obtained from inverse dynamics were decomposed into leg-muscle forces by solving an optimization problem that minimized the sum of the squares of the muscle activations. The predicted knee muscle forces were input into a 3D knee implant contact model to calculate tibial contact forces. Calculated and measured tibial contact forces were in good agreement for all three walking speeds. The average RMS errors for the medial, lateral, and total contact forces over the entire gait cycle and across all trials were 140 +/- 40 N, 115 +/- 32 N, and 183 +/- 45 N, respectively. Muscle coordination predicted by the model was also consistent with EMG measurements reported for normal walking. The combined experimental and modeling approach used in this study provides a quantitative framework for evaluating model predictions of muscle forces in human movement.

  10. RAPID COMMUNICATION: Nanostructured diamond film deposition on curved surfaces of metallic temporomandibular joint implant

    Science.gov (United States)

    Fries, Marc D.; Vohra, Yogesh K.

    2002-10-01

    Microwave plasma chemical vapour deposition of nanostructured diamond films was carried out on curved surfaces of Ti-6Al-4V alloy machined to simulate the shape of a temporomandibular joint (TMJ) dental implant. Raman spectroscopy shows that the deposited films are uniform in chemical composition along the radius of curvature of the TMJ condyle. Thin film x-ray diffraction reveals an interfacial carbide layer and nanocrystalline diamond grains in this coating. Nanoindentation hardness measurements show an ultra-hard coating with a hardness value of 60+/-5 GPa averaged over three samples.

  11. Bioabsorbable Suture Anchor Migration to the Acromioclavicular Joint: How Far Can These Implants Go?

    Directory of Open Access Journals (Sweden)

    Giovanna Medina

    2014-01-01

    Full Text Available Few complications regarding the use of bioabsorbable suture anchors in the shoulder have been reported. What motivated this case report was the unusual location of the anchor, found in the acromioclavicular joint which, to our knowledge, has never been reported so far. A 53-year old male with previous rotator cuff (RC repair using bioabsorbable suture anchors presented with pain and weakness after 2 years of surgery. A suspicion of retear of the RC led to request of a magnetic resonance image, in which the implant was found located in the acromioclavicular joint. The complications reported with the use of metallic implants around the shoulder led to the development of bioabsorbable anchors. Advantages are their absorption over time, minimizing the risk of migration or interference with revision surgery, less artifacts with magnetic resonance imaging, and tendon-to-bone repair strength similar to metallic anchors. Since the use of bioabsorbable suture anchors is increasing, it is important to know the possible complications associated with these devices.

  12. Unyvero i60 implant and tissue infection (ITI) multiplex PCR system in diagnosing periprosthetic joint infection.

    Science.gov (United States)

    Hischebeth, Gunnar T R; Randau, Thomas M; Buhr, Johanna K; Wimmer, Matthias D; Hoerauf, Achim; Molitor, Ernst; Bekeredjian-Ding, Isabelle; Gravius, Sascha

    2016-02-01

    Periprosthetic joint infection (PJI) is one of the most challenging complications in orthopedic surgery. In cases of suspected periprosthetic joint infection several diagnostic methods are available. In this study we investigated the performance of the newly available Unyvero i60 implant and tissue infection (ITI) multiplex PCR System. 62 specimens from 31 patients with suspected PJI or aseptic loosening of a painful joint arthoplasty were included in this study. Besides the established diagnostic procedures we included a commercial multiplex PCR detection system for diagnosis of PJI. The PCR results obtained from analysis of sonication and synovial fluids (62 specimens) showed a sensitivity of 66.7%, a specificity of 100%, a positive predictive value (PPV) of 100% and a negative predictive value (NPV) of 68.4% when compared to cultural methods. Notably, cultures from sonication fluid displayed a sensitivity of 88.9%, a specificity of 61.5%, a PPV of 76.2% and a NPV of 80.0% when compared to tissue cultures. In conclusion, multiplex PCR is an additional - rapid - method for diagnosing PJI. Positive results with the PCR assay used in this study were always confirmed by subsequent matching culture positivity. However, apart from the time saved the nucleic acid amplification technique did not yield additional information than that obtained from microbiological cultures. PMID:26689142

  13. Success of Debridement and Implant Retention in Periprosthetic Joint Infection – Does the Surgeon Matter?

    Science.gov (United States)

    Young, Simon W; Zhu, Mark; Ravi, Saiprasad; Luey, Chris

    2016-01-01

    Objective: Prosthetic joint infection (PJI) is a devastating complication following total joint arthroplasty (TJA). In acute haematogenous and early post-operative PJI, debridement and implant retention (DAIR) surgery is often the initial treatment and success rates vary. This study aimed to identify factors affecting success rates of DAIR and in particular whether involvement of a lower limb arthroplasty surgeon can affect outcome. Method: This retrospective review included one hundred and sixty-two patients undergoing DAIR for first-episode PJI following hip and knee arthroplasty at one of three tertiary hospitals. Treatment success was defined as no relapse within two years of DAIR. Data on patient, hospital, and surgical factors were identified including duration of symptoms, time from primary, previous revisions, age of prosthesis, bacterial subtype, whether modular component exchange was performed and whether an arthroplasty surgeon performed the procedure. Adjusted multivariate analysis was performed to identify factors associated with success of the DAIR procedure. Results: Overall success rate of DAIR in both hip and knee arthroplasty was 60%. A specialist arthroplasty surgeon was present in 42% of cases. Arthroplasty surgeons performed modular exchange in 51% of cases compared to 32.5% for other surgeons. Inclusion of modular exchange in the procedure was the only factor associated with DAIR success (OR 3.1, p<0.013). Time to theatre of less than 24 hours (OR 0.59), duration of symptoms less than one week (OR 1.28), age of prosthesis less than 3 months (OR 1.47) and having an arthroplasty surgeon perform DAIR (OR 1.6) did not lead to statistically significant improvements in success rate. Conclusions: Modular exchange was associated with a significantly higher success rate for both hip and knee PJI, suggesting thorough debridement is important in DAIR. Arthroplasty surgeons were more likely to perform modular exchange, but their presence in theatre alone

  14. Carpometacarpal dislocation of the thumb associated with fracture of the trapezium

    OpenAIRE

    Kose, Ozkan; Keskinbora, Mert; Guler, Ferhat

    2014-01-01

    Carpometacarpal dislocation (CMC) of the thumb associated with fracture of trapezium is an extremely rare injury, with only 12 cases that sustained similar injuries reported in the literature. In this article, another patient with this rare injury was reported, and all previously published cases were extensively reviewed. The presented case and all previously published cases had a longitudinally oriented trapezium fracture, which is naturally unstable and almost always associated with disloca...

  15. Short-term effects of neurodynamic mobilization in 15 patients with secondary thumb carpometacarpal osteoarthritis

    OpenAIRE

    Villafañe, J. H.; Silva, G. B.; Fernández-Camero, Josué

    2011-01-01

    The purpose of this study is to evaluate whether neurodynamic mobilization of the median nerve improves pressure pain threshold (PPT) and pinch and grip strength in patients with secondary thumb carpometacarpal osteoarthritis (TCOA). Fifteen patients with secondary TCOA (13 women and 2 men) between 70 and 90 years old were received by neurodynamic therapy. All patients received median nerve mobilization of the dominant hand by sliding technique during 4 sessions over 2 weeks. The outcome meas...

  16. Methotrexate pharmacotherapy for implant-related temporomandibular joint pain: a case report.

    Science.gov (United States)

    Edwards, J Paul; Peterson, Erik J; Durham, Justin; Nixdorf, Donald R

    2014-08-01

    This article presents a patient experiencing several years of pain associated with bilateral failed temporomandibular joint (TMJ) Proplast/Teflon fossa prostheses. Despite surgical removal of the prostheses and comprehensive conservative management, including typical pharmacotherapy approaches for chronic pain, pain was still not relieved, and management was revised to target a putative chronic inflammatory disorder. Methotrexate was prescribed because of its known efficacy for inflammation and pain reduction in rheumatoid arthritis. Titration of methotrexate dosage over 5 months to a weekly dose of 20 mg resulted in reduced pain intensity at rest, increased pain-free maximal jaw opening, and a reduction in the sensory component of the McGill Pain Questionnaire. Maximum assisted jaw opening remained the same, as did the palpation tenderness of both TMJs and of the masseter and temporalis muscles. Methotrexate pharmacotherapy may represent a viable option when conservative treatments have failed to provide significant pain relief in patients who have had Proplast/Teflon TMJ implants. PMID:25047933

  17. [Partial replacement of the knee joint with patient-specific instruments and implants (ConforMIS iUni, iDuo)].

    Science.gov (United States)

    Beckmann, J; Steinert, A; Zilkens, C; Zeh, A; Schnurr, C; Schmitt-Sody, M; Gebauer, M

    2016-04-01

    Knee arthroplasty is a successful standard procedure in orthopedic surgery; however, approximately 20 % of patients are dissatisfied with the clinical results as they suffer pain and can no longer achieve the presurgery level of activity. According to the literature the reasons are inexact fitting of the prosthesis or too few anatomically formed implants resulting in less physiological kinematics of the knee joint. Reducing the number of dissatisfied patients and the corresponding number of revisions is an important goal considering the increasing need for artificial joints. In this context, patient-specific knee implants are an obvious alternative to conventional implants. For the first time implants are now matched to the individual bone and not vice versa to achieve the best possible individual situation and geometry and more structures (e.g. ligaments and bone) are preserved or only those structures are replaced which were actually destroyed by arthrosis. According to the authors view, this represents an optimal and pioneering addition to conventional implants. Patient-specific implants and the instruments needed for correct alignment and fitting can be manufactured by virtual 3D reconstruction and 3D printing based on computed tomography (CT) scans. The portfolio covers medial as well as lateral unicondylar implants, medial as well as lateral bicompartmental implants (femorotibial and patellofemoral compartments) and cruciate ligament-preserving as well as cruciate ligament-substituting total knee replacements; however, it must be explicitly emphasized that the literature is sparse and no long-term data are available. PMID:26984107

  18. Patient and implant survival following joint replacement because of metastatic bone disease

    DEFF Research Database (Denmark)

    Sørensen, Michala S; Gregersen, Kristine G; Grum-Schwensen, Tomas;

    2013-01-01

    Patients suffering from a pathological fracture or painful bony lesion because of metastatic bone disease often benefit from a total joint replacement. However, these are large operations in patients who are often weak. We examined the patient survival and complication rates after total joint...

  19. Finite element analysis of Ti-based knee-joint implant

    Directory of Open Access Journals (Sweden)

    L. Zach

    2015-10-01

    Full Text Available The focus of this paper was on finite element analysis of a PROSPON oncological knee endoprosthesis. The 3D CAD knee joint model, the designed FE PROSPON prosthesis model into which was integrated, was created on the basis of Visible Human Project CT scans. Analyses of stress state and contact pressures were performed in the kneebending position within 15,4° - 69,4° hip joint flection range. The results showed that the maximum achieved stress did not exceed the yield strength (90 MPa of the material. The results of the stress state were in accordance with the distribution of contact pressure.

  20. Functionally deficient mesenchymal stem cells reside in the bone marrow niche with M2-macrophages and amyloid-β protein adjacent to loose total joint implants.

    Science.gov (United States)

    Margulies, Bryan S; DeBoyace, Sean D; Parsons, Adrienne M; Policastro, Connor G; Ee, Jessica S S; Damron, Timothy S

    2015-05-01

    We sought to demonstrate whether there is a difference in the local mesenchymal stem cells (MSC) niche obtained from patients undergoing their first total joint replacement surgery versus those patients undergoing a revision surgery for an failing total joint implant. Bone marrow aspirates collected from patients undergoing revision total joint arthroplasty were observed to be less clonal and the expression of PDGFRα, CD51, ALCAM, endoglin, CXCL12, nestin, and nucleostemin were decreased. Revision MSC were also less able to commit to an osteoblast-lineage or an adipocyte-lineage. Further, in revision MSC, OPG, and IL6 expression were increased. Monocytes, derived from revision whole marrow aspirates, were less capable of differentiating into osteoclasts, the cells implicated in the pathologic degradation of bone. Osteoclasts were also not observed in tissue samples collected adjacent to the implants of revision patients; however, the alternatatively activated M2-macrophage phenotype was observed in parallel with pathologic accumulations of amyloid-β, τ-protien and 3-nitrotyrosine. Despite the limited numbers of patients examined, our data suggest that nucleostemin may be a useful functional marker for MSC while the observation of M2-macrophage infiltration around the implant lays the foundation for future investigation into a novel mechanism that we propose is associated with loose total joint implants.

  1. Absence of Flexor Carpi Radialis during an Elective Carpometacarpal Arthroplasty of the Thumb: A Rare Anatomical Variation

    Directory of Open Access Journals (Sweden)

    Stratos S. Sofos

    2016-01-01

    Full Text Available Purpose. We present an extremely rare anatomical variation of unilateral flexor carpi radialis (FCR absence. This rare anatomical variation posed a clinical dilemma to us and we highlight the importance of the surgeon being aware of this anatomical variation of an important structure both as a reconstruction tool and as an anatomical landmark. Methods. This anatomical variation of the unilaterally absent FCR was found upon dissection during a carpometacarpal arthroplasty of the thumb. Results. Upon the discovery of an absent FCR tendon, we proceeded with a simple trapeziectomy. Conclusions. We present an extremely rare anatomical variation of unilateral FCR absence. This rare anatomical variation may pose clinical dilemmas to the operating surgeon who aims to utilise the FCR either for tendon transfer, for tendon graft, or, as seen in our case, in the reconstruction of a carpometacarpal excision at the thumb. We highlight this diagnosis of suspicion, which may influence the clinical procedure.

  2. The influence of footwear on knee joint loading during walking--in vivo load measurements with instrumented knee implants.

    Science.gov (United States)

    Kutzner, Ines; Stephan, Daniel; Dymke, Jörn; Bender, Alwina; Graichen, Friedmar; Bergmann, Georg

    2013-02-22

    Since footwear is commonly used every day, its influence on knee joint loading and thereby on the development and progression of osteoarthritis may be crucial. So far the influence of footwear has been examined only indirectly. The aim of this study was to directly measure the effect of footwear on tibiofemoral contact loads during walking. Instrumented knee implants with telemetric data transmission were used to measure the tibiofemoral contact forces and moments in six subjects. The loads during walking with four different shoes (basic running shoes, advanced running shoes, classical dress shoes and shoes with a soft rounded sole in the sagittal plane (MBT)) were compared to those during barefoot walking. Peak values of all six load components were analyzed. In general, footwear tended to increase knee joint loading slightly, with the dress shoe being the most unfavorable type of footwear. At the early stance phase all load components were increased by all shoe types. The resultant force rose by 2-5%, the internal adduction moment by 7-12% and the forces on the medial compartment by 3-5%. Significant reductions of the resultant force were solely observed for the advanced running shoe (-6%) and the MBT (-9%) shoe at late stance. Also the medial compartment force was slightly yet non-significantly reduced by 2-5% with the two shoes. It is questionable whether such small load changes have an influence on the progression of gonarthrosis. Future research is necessary to examine which factors regarding the shoe design, such as heel height, arch support or flexibility are most decisive for a reduction of knee joint loading.

  3. Complications with infection and foreign body reaction after silicon implant arthroplasty in the second metatarsophalangeal joint in an adolescent: a case report.

    Science.gov (United States)

    Felländer-Tsai, L; Reinholt, F P; Turan, I

    1997-01-01

    A 21-year-old otherwise healthy male was referred to our clinic due to severe pain, deformation, development of fistules, and swelling of the second metatarsophalangeal joint of the right foot. He presented a history of two previous operations. At the age of 13, a 2-cm. resection of the distal part of the proximal phalanx was performed due to severe hammertoe deformity. At the age of 19, a partial phalanx resection and implantation of a silicon elastomer ball-shaped joint spacer was performed due to second metatarsophalangeal joint instability. After this operation, the patient suffered from fistules that appeared in the second metatarsophalangeal region. Following referral to our clinic, the patient was operated on. The proximal phalanx was removed along with the prosthesis which had slipped from the metatarsophalangeal joint into the proximal phalanx with the ends of the prosthesis perforating the skin. Debridement of infected tissue and implantation of gentamicin containing beads were performed. Bacterial specimens revealed growth of coagulase-negative staphylococci. Microscopic examination of the debrided tissue showed signs of acute and chronic inflammation. Postoperatively, the patient was treated with antibiotics and healing was uneventful. This case advocates the need for proper selection criteria and strict indications in patients with joint disease needing an arthroplasty. PMID:9430001

  4. Bone cement/layered double hydroxide nanocomposites as potential biomaterials for joint implant.

    Science.gov (United States)

    Kapusetti, Govinda; Misra, Nira; Singh, Vakil; Kushwaha, R K; Maiti, Pralay

    2012-12-01

    Poly(methyl methacrylate)-based bone cement and layered double hydroxide (LDH) nanocomposites have been used as a grouting material for total joint arthroplasty. Few weight percentage of nanoLDH was uniformly dispersed in the bone cement matrix to have adequate interaction with matrix polymer. Mechanical strength, stiffness, toughness, and fatigue resistance of the nanocomposites are found to be higher than that of pure bone cement. Nanocomposites are thermally stable as compared to pristine bone cement. Direct mixing of the nanoLDH without any organic solvent makes these nanocomposites biocompatible. Biocompatibility was evaluated and compared with that of commercial bone cement by measuring hydrophilic nature, hemolysis assay, thrombosis assay, and deposition of apatite in simulated body fluid immersion. Finally, the viability of human osteoblast cells on the above developed nanocomposites was testified for actual biocompatibility. The experiment showed better cell growth in nanocomposites as compared to pure bone cement. Thus, these nanocomposites are found to be better grouting material than bone cement. PMID:22733710

  5. A mouse model of post-arthroplasty Staphylococcus aureus joint infection to evaluate in vivo the efficacy of antimicrobial implant coatings.

    Directory of Open Access Journals (Sweden)

    Nicholas M Bernthal

    Full Text Available BACKGROUND: Post-arthroplasty infections represent a devastating complication of total joint replacement surgery, resulting in multiple reoperations, prolonged antibiotic use, extended disability and worse clinical outcomes. As the number of arthroplasties in the U.S. will exceed 3.8 million surgeries per year by 2030, the number of post-arthroplasty infections is projected to increase to over 266,000 infections annually. The treatment of these infections will exhaust healthcare resources and dramatically increase medical costs. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate novel preventative therapeutic strategies against post-arthroplasty infections, a mouse model was developed in which a bioluminescent Staphylococcus aureus strain was inoculated into a knee joint containing an orthopaedic implant and advanced in vivo imaging was used to measure the bacterial burden in real-time. Mice inoculated with 5x10(3 and 5x10(4 CFUs developed increased bacterial counts with marked swelling of the affected leg, consistent with an acute joint infection. In contrast, mice inoculated with 5x10(2 CFUs developed a low-grade infection, resembling a more chronic infection. Ex vivo bacterial counts highly correlated with in vivo bioluminescence signals and EGFP-neutrophil fluorescence of LysEGFP mice was used to measure the infection-induced inflammation. Furthermore, biofilm formation on the implants was visualized at 7 and 14 postoperative days by variable-pressure scanning electron microscopy (VP-SEM. Using this model, a minocycline/rifampin-impregnated bioresorbable polymer implant coating was effective in reducing the infection, decreasing inflammation and preventing biofilm formation. CONCLUSIONS/SIGNIFICANCE: Taken together, this mouse model may represent an alternative pre-clinical screening tool to evaluate novel in vivo therapeutic strategies before studies in larger animals and in human subjects. Furthermore, the antibiotic-polymer implant coating

  6. Results of Abductor Pollicis Longus Suspension Ligamentoplasty for Treatment of Advanced First Carpometacarpal Arthritis

    Science.gov (United States)

    Lee, Hyun-Joo; Kim, Poong-Taek; Deslivia, Maria Florencia; Lee, Suk-Joong; Nam, Sang-Jin

    2015-01-01

    Background Suspension ligamentoplasty using abductor pollicis longus (APL) tendon without bone tunneling, was introduced as one of the techniques for treatment of advanced first carpometacarpal (CMC) arthritis. The purpose of this study was to evaluate the radiologic and clinical results of APL suspension ligamentoplasty. Methods The medical records of 19 patients who underwent APL suspension ligamentoplasty for advanced first CMC arthritis between January 2008 and May 2012 were reviewed retrospectively. The study included 13 female and 6 male patients, whose mean age was 62 years (range, 43 to 82 years). For clinical evaluation, we assessed the grip and pinch power, radial and volar abduction angle, thumb adduction (modified Kapandji index), including visual analogue scale (VAS) and Disabilities of the Arm, Shoulder and Hand (DASH) scores. Radiologic evaluation was performed using simple radiographs. Results The mean follow-up was 36 months (range, 19 to 73.7 months). Mean power improved from 18.3 to 27 kg for grip power, from 2.8 to 3.5 kg for tip pinch, and from 4.3 to 5.4 kg for power pinch. All patients showed decreased VAS from 7.2 to 1.7. Radial abduction improved from 71° preoperatively to 82° postoperatively. The modified Kapandji index showed improvement from 6 to 7.3, and mean DASH was improved from 41 to 17.8. The height of the space decreased from 10.8 to 7.1 mm. Only one case had a complication involving temporary sensory loss of the first dorsal web space, which resolved spontaneously. Conclusions The APL suspension ligamentoplasty for treatment of advanced first CMC arthritis yielded satisfactory functional results. PMID:26330961

  7. One-year outcomes after minimally invasive sacroiliac joint fusion with a series of triangular implants: a multicenter, patient-level analysis

    Directory of Open Access Journals (Sweden)

    Sachs D

    2014-08-01

    Full Text Available Donald Sachs,1 Robyn Capobianco,2 Daniel Cher,2 Timothy Holt,3 Mukund Gundanna,4 Timothy Graven,5 A Nick Shamie,6 John Cummings Jr7 1Center for Spinal Stenosis and Neurologic Care, Lakeland, FL, 2SI-BONE, Inc., San Jose, CA, 3Montgomery Spine Center, Montgomery, AL, 4Brazos Spine, College Station, TX, 5SSM Orthopedics, Wentzville, MO, 6UCLA Spine Center, Santa Monica, CA, 7Community Neurosurgical Care, Indianapolis, IN, USA Background: Sacroiliac joint (SI pain is an often-overlooked cause of lower-back pain, due in part to a lack of specific findings on radiographs and a symptom profile similar to other back-related disorders. A minimally invasive surgical (MIS approach to SI joint fusion using a series of triangular, titanium plasma spray-coated implants has shown favorable outcomes in patients with SI joint pain refractory to conservative care. The aim of this study was to provide a multicenter experience of MIS SI joint fusion using a patient-level analysis. Patients and methods: We report a patient-level analysis from 144 patients with a mean of 16 months postoperative follow-up. Demographic information, perioperative measures, complications, and clinical outcomes using a visual analog scale for pain were collected prospectively. Random-effects regression models were used to account for intersite variability. Results: The mean age was 58 years, 71% of patients were female, and 62% had a history of lumbar spinal fusion. Mean (95% confidence interval [CI] operative time was 73 minutes (25.4–118, blood loss was minimal, and hospital stay was 0.8 days (0.1–1.5. At follow-up, mean (95% CI visual analog scale pain scores improved by 6.1 points (5.7–6.6. Substantial clinical benefit, defined as a decrease in pain by >2.5 points or a score of 3.5 or less, was achieved in 91.9% of patients (95% CI 83.9%–96.1%, and 96% (95% CI 86.3%–98.8% of patients indicated they would have the same surgery again. Conclusion: When conservative measures

  8. Modelling of the mechanical behavior of a polyurethane finger interphalangeal joint endoprosthesis after surface modification by ion implantation

    Science.gov (United States)

    Beliaev, A.; Svistkov, A.; Iziumov, R.; Osorgina, I.; Kondyurin, A.; Bilek, M.; McKenzie, D.

    2016-04-01

    Production of biocompatible implants made of polyurethane treated with plasma is very perspective. During plasma treatment the surface of polyurethane acquires unique physic-chemical properties. However such treatment may change the mechanical properties of polyurethane which may adversely affect the deformation behaviour of the real implant. Therefore careful study of the mechanical properties of the plasma-modified polyurethane is needed. In this paper, experimental observations of the elastic characteristics of plasma treated polyurethane and modelling of the deformation behaviour of polyurethane bio-implants are reported.

  9. Shoulder Joint Replacement

    Science.gov (United States)

    ... en because of implant loosening, wear, infection, and dislocation. When this occurs, a second joint replacement surgery — called a revision surgery — may be necessary. Is Shoulder Joint Replacement for You? The decision to have ...

  10. A neural network approach for determining gait modifications to reduce the contact force in knee joint implant.

    Science.gov (United States)

    Ardestani, Marzieh Mostafavizadeh; Chen, Zhenxian; Wang, Ling; Lian, Qin; Liu, Yaxiong; He, Jiankang; Li, Dichen; Jin, Zhongmin

    2014-10-01

    There is a growing interest in non-surgical gait rehabilitation treatments to reduce the loading in the knee joint. In particular, synergetic kinematic changes required for joint offloading should be determined individually for each subject. Previous studies for gait rehabilitation designs are typically relied on a "trial-and-error" approach, using multi-body dynamic (MBD) analysis. However MBD is fairly time demanding which prevents it to be used iteratively for each subject. This study employed an artificial neural network to develop a cost-effective computational framework for designing gait rehabilitation patterns. A feed forward artificial neural network (FFANN) was trained based on a number of experimental gait trials obtained from literature. The trained network was then hired to calculate the appropriate kinematic waveforms (output) needed to achieve desired knee joint loading patterns (input). An auxiliary neural network was also developed to update the ground reaction force and moment profiles with respect to the predicted kinematic waveforms. The feasibility and efficiency of the predicted kinematic patterns were then evaluated through MBD analysis. Results showed that FFANN-based predicted kinematics could effectively decrease the total knee joint reaction forces. Peak values of the resultant knee joint forces, with respect to the bodyweight (BW), were reduced by 20% BW and 25% BW in the midstance and the terminal stance phases. Impulse values of the knee joint loading patterns were also decreased by 17% BW*s and 24%BW*s in the corresponding phases. The FFANN-based framework suggested a cost-effective forward solution which directly calculated the kinematic variations needed to implement a given desired knee joint loading pattern. It is therefore expected that this approach provides potential advantages and further insights into knee rehabilitation designs.

  11. Literacy Skills in Children With Cochlear Implants: The Importance of Early Oral Language and Joint Storybook Reading

    OpenAIRE

    DesJardin, Jean L.; Ambrose, Sophie E.; Eisenberg, Laurie S.

    2008-01-01

    The goal of this study was to longitudinally examine relationships between early factors (child and mother) that may influence children's phonological awareness and reading skills 3 years later in a group of young children with cochlear implants (N = 16). Mothers and children were videotaped during two storybook interactions, and children's oral language skills were assessed using the “Reynell Developmental Language Scales, third edition.” Three years later, phonological awareness, reading sk...

  12. The EULAR-OMERACT rheumatoid arthritis MRI reference image atlas: the wrist joint

    DEFF Research Database (Denmark)

    Ejbjerg, B; McQueen, F; Lassere, M;

    2005-01-01

    This paper presents the wrist joint MR images of the EULAR-OMERACT rheumatoid arthritis MRI reference image atlas. Reference images for scoring synovitis, bone oedema, and bone erosions according to the OMERACT RA MRI scoring (RAMRIS) system are provided. All grades (0-3) of synovitis are......, capitate, and a metacarpal base. In these bones, grades 0-3 of bone oedema are illustrated, and for bone erosion, grades 0-3 and examples of higher grades are presented. The presented reference images can be used to guide scoring of wrist joints according to the OMERACT RA MRI scoring system...... illustrated in each of the three wrist joint areas defined in the scoring system-that is, the distal radioulnar joint, the radiocarpal joint, and the intercarpal-carpometacarpal joints. For reasons of feasibility, examples of bone abnormalities are limited to five selected bones: the radius, scaphoid, lunate...

  13. Durable intermediate- to long-term outcomes after minimally invasive transiliac sacroiliac joint fusion using triangular titanium implants

    Directory of Open Access Journals (Sweden)

    Sachs D

    2016-07-01

    Full Text Available Donald Sachs,1 Don Kovalsky,2 Andy Redmond,3 Robert Limoni,4 S Craig Meyer,5 Charles Harvey,6 Dimitriy Kondrashov7 1Center for Spinal Stenosis and Neurologic Care, Lakeland, FL, 2Orthopaedic Center of Southern Illinois, Mount Vernon, IL, 3Precision Spine Care, Tyler, TX, 4BayCare Clinic, Green Bay, WI, 5Columbia Orthopaedic Group, Columbia, MO, 6Riverside Medical Center, Kankakee, IL, 7SF Spine Group at St Mary’s Spine Center, San Francisco, CA, USA Background: Sacroiliac joint (SIJ fusion (SIJF, first performed 95 years ago, has become an increasingly accepted surgical option for chronic SIJ dysfunction. Few studies have reported intermediate- or long-term outcomes after SIJF.Objective: The objective of this study is to determine patient-based outcomes after SIJF for chronic SIJ dysfunction due to degenerative sacroiliitis or SIJ disruption at ≥3 years of follow-up.Methods: Consecutive patients who underwent SIJF prior to December 2012 were contacted over phone or through email. Participants completed questionnaires in clinic, over phone or by email, regarding SIJ pain, activities related to SIJ dysfunction, and the Oswestry Disability Index. Charts were reviewed to extract baseline parameters and the clinical course of follow-up.Results: One hundred seven patients were eligible and participated in this study. Mean (standard deviation preoperative SIJ pain score was 7.5 (1.7. At mean follow-up of 3.7 years, the mean SIJ pain score was 2.6 (representing a 4.8-point improvement from baseline, P<0.0001 and the mean Oswestry Disability Index was 28.2. The ability to perform activities commonly impaired by SIJ dysfunction showed positive improvements in most patients. SIJ revision surgery was uncommon (five patients, 4.7%. Fourteen patients (13.1% underwent contralateral SIJF during follow-up, 25.2% of patients had additional non-SIJ-related lumbar spine or hip surgeries during follow-up.Conclusion: In intermediate- to long-term follow

  14. Short- versus long-duration levofloxacin plus rifampicin for acute staphylococcal prosthetic joint infection managed with implant retention: a randomised clinical trial.

    Science.gov (United States)

    Lora-Tamayo, Jaime; Euba, Gorane; Cobo, Javier; Horcajada, Juan Pablo; Soriano, Alex; Sandoval, Enrique; Pigrau, Carles; Benito, Natividad; Falgueras, Luis; Palomino, Julián; Del Toro, María Dolores; Jover-Sáenz, Alfredo; Iribarren, José Antonio; Sánchez-Somolinos, Mar; Ramos, Antonio; Fernández-Sampedro, Marta; Riera, Melchor; Baraia-Etxaburu, Josu Mirena; Ariza, Javier

    2016-09-01

    Levofloxacin plus rifampicin (L+R) is the treatment of choice for acute staphylococcal prosthetic joint infection (PJI) managed with debridement and implant retention (DAIR). Long courses have been empirically recommended, but some studies have suggested that shorter treatments could be as effective. Our aim was to prove that a short treatment schedule was non-inferior to the standard long schedule. An open-label, multicentre, randomised clinical trial (RCT) was performed. Patients with an early post-surgical or haematogenous staphylococcal PJI, managed with DAIR and initiated on L+R were randomised to receive 8 weeks of treatment (short schedule) versus a long schedule (3 months or 6 months for hip or knee prostheses, respectively). The primary endpoint was cure rate. From 175 eligible patients, 63 were included (52% women; median age, 72 years): 33 patients (52%) received the long schedule and 30 (48%) received the short schedule. There were no differences between the two groups except for a higher rate of polymicrobial infection in the long-schedule group (27% vs. 7%; P = 0.031). Median follow-up was 540 days. In the intention-to-treat analysis, cure rates were 58% and 73% in patients receiving the long and short schedules, respectively (difference -15.7%, 95% CI -39.2% to 7.8%). Forty-four patients (70%) were evaluable per-protocol: cure rates were 95.0% and 91.7% for the long and short schedules, respectively (difference 3.3%, 95% CI -11.7% to 18.3%). This is the first RCT suggesting that 8 weeks of L+R could be non-inferior to longer standard treatments for acute staphylococcal PJI managed with DAIR. PMID:27524103

  15. HA-Coated Implant

    DEFF Research Database (Denmark)

    Daugaard, Henrik; Søballe, Kjeld; Bechtold, Joan E

    2014-01-01

    The goal of osseointegration of orthopedic and dental implants is the rapid achievement of a mechanically stable and long lasting fixation between living bone and the implant surface. In total joint replacements of cementless designs, coatings of calcium phosphates were introduced as a means...... of improving the fixation of implants. Of these, hydroxyapatite (HA) is the most widely used and most extensively investigated. HA is highly osseoconductive, and the positive effect is well documented in both basic and long-term clinical research [1–6]. This chapter describes experimental and clinical studies...... evaluating bone-implant fixation with HA coatings....

  16. Two years follow-up study of the pain-relieving effect of gold bead implantation in dogs with hip-joint arthritis

    Directory of Open Access Journals (Sweden)

    Søli Nils

    2007-03-01

    Full Text Available Abstract Seventy-eight dogs with pain from hip dysplasia participated in a six-month placebo-controlled, double-blinded clinical trial of gold bead implantation. In the present, non-blinded study, 73 of these dogs were followed for an additional 18 months to evaluate the long-term pain-relieving effect of gold bead implantation. The recently-published results of the six month period revealed that 30 of the 36 dogs (83% in the gold implantation group showed significant improvement (p = 0.02, included improved mobility and reduction in the signs of pain, compared to the placebo group (60% improvement. In the long-term two-year follow-up study, 66 of the 73 dogs had gold implantation and seven dogs continued as a control group. The 32 dogs in the original placebo group had gold beads implanted and were followed for a further 18 months. A certified veterinary acupuncturist used the same procedure to insert the gold beads as in the blinded study, and the owners completed the same type of detailed questionnaires. As in the blinded study, one investigator was responsible for all the assessments of each dog. The present study revealed that the pain-relieving effect of gold bead implantation observed in the blinded study continued throughout the two-year follow-up period.

  17. Superelastic Orthopedic Implant Coatings

    Science.gov (United States)

    Fournier, Eric; Devaney, Robert; Palmer, Matthew; Kramer, Joshua; El Khaja, Ragheb; Fonte, Matthew

    2014-07-01

    The demand for hip and knee replacement surgery is substantial and growing. Unfortunately, most joint replacement surgeries will fail within 10-25 years, thereby requiring an arduous, painful, and expensive revision surgery. To address this issue, a novel orthopedic implant coating material ("eXalt") has been developed. eXalt is comprised of super elastic nitinol wire that is knit into a three-dimensional spacer fabric structure. eXalt expands in vivo to conform to the implantation site and is porous to allow for bone ingrowth. The safety and efficacy of eXalt were evaluated through structural analysis, mechanical testing, and a rabbit implantation model. The results demonstrate that eXalt meets or exceeds the performance of current coating technologies with reduced micromotion, improved osseointegration, and stronger implant fixation in vivo.

  18. Arthroscopic Fixation of Cell Free Polymer-Based Cartilage Implants with a Bioinspired Polymer Surface on the Hip Joint: A Cadaveric Pilot Study

    Directory of Open Access Journals (Sweden)

    Matthias Lahner

    2014-01-01

    Full Text Available This study investigates the adhesion capacity of a polyglycolic acid- (PGA- hyaluronan scaffold with a structural modification based on a planar polymer (PM surface in a cadaver cartilage defect model. Two cadaver specimens were used to serially test multiple chondral matrices. In a cadaver hip model, cell free polymer-based cartilage implants with a planar bioinspired PM surface (PGA-PM-scaffolds were implanted arthroscopically on 10 mm × 15 mm full-thickness femoral hip cartilage lesions. Unprocessed cartilage implants without a bioinspired PM surface were used as control group. The cartilage implants were fixed without and with the use of fibrin glue on femoral hip cartilage defects. After 50 movement cycles and removal of the distraction, a rearthroscopy was performed to assess the outline attachment and integrity of the scaffold. The fixation techniques without and with fibrin fixation showed marginal differences for outline attachment, area coverage, scaffold integrity, and endpoint fixation after 50 cycles. The PGA-PM-scaffolds with fibrin fixation achieved a higher score in terms of the attachment, integrity, and endpoint fixation than the PGA-scaffold on the cartilage defect. Relating to the outline attachment, area coverage, scaffold integrity, and endpoint fixation, the fixation with PGA-PM-scaffolds accomplished significantly better results compared to the PGA-scaffolds (P=0.03752, P=0.03078, P=0.00512, P=0.00512. PGA-PM-scaffolds demonstrate increased observed initial fixation strength in cadaver femoral head defects relative to PGA-scaffold, particularly when fibrin glue is used for fixation.

  19. Specificities of physioterapy care after the convetional implantation of a total knee-joint in relation to its different surgical solutions

    OpenAIRE

    ŠMITMAJER, Jakub

    2014-01-01

    The main aim of this bachelor study is concentrated on an after- total- knee- joint endoprosthesis physiotherapy from the surgical solution point of view. The total endoprosthesis is used as the very last possible option of an invasive means of therapy that is possible to take an advantage of when there is extensive damage of biomechanics of a knee joint. When speaking about the frequency of this operation, it is very high, and it is becoming a more and more common way of surgery that is nowa...

  20. 锁骨钩钢板置入治疗Rockwood Ⅲ型肩锁关节脱位%Clavicular hook plate implantation for the treatment of Rockwood type Ⅲ acromioclavicular joint dislocation

    Institute of Scientific and Technical Information of China (English)

    张建华; 聂宇; 周永焕; 王光勇; 敦先礼; 李有方; 周廷玉; 钟斌

    2012-01-01

    背景:多数学者主张手术治疗RockwoodⅢ型肩锁关节脱位,以恢复肩锁关节周围稳定结构的正常解剖,使之在无张力的条件下愈合.目的:观察锁骨钩板置入治疗RockwoodⅢ型肩锁关节脱位的临床疗效.方法:选择2005-12/2008-06宜昌市夷陵区医院骨科和五峰土家族自治县人民医院骨科收治的Rockwood Ⅲ型肩锁关节脱位患者56例,采用锁骨钩钢板置入进行治疗,分别于置入前、置入后1年取出内固定前、取出内固定后3个月采用目测类比评分、美国肩肘外科医师评分、Constant肩关节评分系统评分进行评定,比较钢板置入前后患者肩关节功能的变化及有无并发症发生.结果与结论:全部患者均顺利完成手术且获得随访,随访时间15~30个月,平均20个月.均在1年左右取出锁骨钩钢板,行喙锁韧带修复者32例,未行喙锁韧带修复者24例.取出内固定后肩锁关节脱位复发2例,均未行喙锁韧带修复.本组有2例出现肩痛、异物感,无内固定失败病例.术后1年取内固定前目测类比评分较术前降低,美国肩肘外科医师评分、Constant肩关节评分系统评分较术前升高(P < 0.01);取内固定后3个月目测类比评分较术后1年取内固定前降低,美国肩肘外科医师评分、Constant肩关节评分系统评分较术后1年取内固定前升高(P < 0.05).提示锁骨钩板置入治疗RockwoodⅢ型肩锁关节脱位,操作简单,创伤较小,是一种比较理想的内固定.%BACKGROUND: Surgical therapy has been frequently used to treat Rockwood type Ⅲ acromioclavicular joint dislocation to restore normal anatomy of stable structures around the acromioclavicular joint and heal free of tension.OBJECTIVE: To investigate the clinical effect of clavicular hook plate implantation on Rockwood type Ⅲ acromioclavicular joint dislocation.METHODS: A total of 56 patients with Rockwood type Ⅲ acromioclavicular joint dislocation were selected from

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

    Science.gov (United States)

    Cao, Shaoping; Yin, Chunguang; Zhao, Zhenying

    2013-03-01

    Through the establishment of implantable medical device information management system, with the aid of the regional joint sharing of resources, we further enhance the implantable medical device traceability management level, strengthen quality management, control of medical risk. PMID:23777076

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

    Science.gov (United States)

    Cao, Shaoping; Yin, Chunguang; Zhao, Zhenying

    2013-03-01

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

  3. Remoção da cartilagem articular associada ou não a implante homógeno ou enxerto autógeno de osso esponjoso em cães submetidos à artrodese atlantoaxial Joint cartilage removal associated or not to homologous implant or autologous cancellous bone graft in dogs submitted to atlantoaxial arthrodesis

    Directory of Open Access Journals (Sweden)

    Rafael Festugatto

    2013-03-01

    Full Text Available O objetivo deste estudo foi avaliar o grau de fusão articular e formação óssea na articulação atlantoaxial de cães submetidos à artrodese após a remoção da cartilagem articular associada ou não ao implante homógeno ou enxerto autógeno de osso esponjoso. Foram utilizados 12 cães, adultos, distribuídos aleatoriamente em três grupos iguais. Grupo I (GI: realizada apenas a remoção da cartilagem articular e imobilização articular com pinos e resina acrílica. Grupo II (GII: feita a remoção da cartilagem articular e imobilização da articulação, seguida da colocação e modelagem do implante ósseo esponjoso homógeno entre as superfícies articulares. Grupo III (GIII: foi realizado o mesmo procedimento do GII, mais o enxerto ósseo esponjoso autógeno no local determinado. Realizaram-se exames radiográficos em todos os animais aos 30, 60 e 90 dias de pós-operatório (PO. Aos 90 dias de PO foi feita a eutanásia para o emprego do teste de palpação manual, avaliação tomográfica e histopatológica. Para análise estatística da associação entre o grau de fusão articular, aplicou-se o Teste Qui-quadrado de independência. Os resultados dos testes foram avaliados pela significância exata e considerados significantes a 5% (PThe aim of this study was to evaluate the degree of joint fusion and bone formation in dogs undergoing atlantoaxial arthrodesis after removal of articular cartilage associated or not to implant homogenous or autogenous cancellous bone. Twelve dogs, weighing between 8 and 12kg were randomly divided into three groups. Group I (GI performed only the removal of joint cartilage and joint immobilization with acrylic resin and pins. Group II (GII: after removel of joint cartilage and articular immobilization was performed modeling and placement of homogenous cancellous bone at the given location. The volume of homograft placed in the joint was measured using a precision balance and all animals received the

  4. Preserving the Posttrapeziectomy Space with a Human Acellular Dermal Matrix Spacer: A Pilot Case Series of Patients with Thumb Carpometacarpal Joint Arthritis

    Directory of Open Access Journals (Sweden)

    Caroline A. Yao, MD

    2013-10-01

    Conclusions: HADM has been used extensively in other forms of reconstruction and has been shown to incorporate into surrounding tissues through neovascularization. Our early results illustrate that HADM can safely fill the dead space left by trapeziectomy.

  5. Periprosthetic Joint Infections

    Directory of Open Access Journals (Sweden)

    Ana Lucia L. Lima

    2013-01-01

    Full Text Available Implantation of joint prostheses is becoming increasingly common, especially for the hip and knee. Infection is considered to be the most devastating of prosthesis-related complications, leading to prolonged hospitalization, repeated surgical intervention, and even definitive loss of the implant. The main risk factors to periprosthetic joint infections (PJIs are advanced age, malnutrition, obesity, diabetes mellitus, HIV infection at an advanced stage, presence of distant infectious foci, and antecedents of arthroscopy or infection in previous arthroplasty. Joint prostheses can become infected through three different routes: direct implantation, hematogenic infection, and reactivation of latent infection. Gram-positive bacteria predominate in cases of PJI, mainly Staphylococcus aureus and Staphylococcus epidermidis. PJIs present characteristic signs that can be divided into acute and chronic manifestations. The main imaging method used in diagnosing joint prosthesis infections is X-ray. Computed tomography (CT scan may assist in distinguishing between septic and aseptic loosening. Three-phase bone scintigraphy using technetium has high sensitivity, but low specificity. Positron emission tomography using fluorodeoxyglucose (FDG-PET presents very divergent results in the literature. Definitive diagnosis of infection should be made by isolating the microorganism through cultures on material obtained from joint fluid puncturing, surgical wound secretions, surgical debridement procedures, or sonication fluid. Success in treating PJI depends on extensive surgical debridement and adequate and effective antibiotic therapy. Treatment in two stages using a spacer is recommended for most chronic infections in arthroplasty cases. Treatment in a single procedure is appropriate in carefully selected cases.

  6. Carmustine Implant

    Science.gov (United States)

    Carmustine implant is used along with surgery and sometimes radiation therapy to treat malignant glioma (a certain type of ... Carmustine implant comes as a small wafer that is placed in the brain by a doctor during surgery to ...

  7. Goserelin Implant

    Science.gov (United States)

    Goserelin implant is used in combination with radiation therapy and other medications to treat localized prostate cancer and is ... treatment of abnormal bleeding of the uterus. Goserelin implant is in a class of medications called gonadotropin- ...

  8. A simulating analysis of the effects of increased joint stiffness on muscle loading in a thumb

    Directory of Open Access Journals (Sweden)

    Cutlip Robert G

    2009-12-01

    Full Text Available Abstract Background The development of osteoarthritis (OA in the hand results in increased joint stiffness, which in turn affects the grip strength. The goal of the present study is to theoretically analyze the muscle forces in a thumb in response to the increased joint stiffness. Methods The thumb was modeled as a linkage system consisting of a trapezium, a metacarpal bone, a proximal and a distal phalanx. Nine muscles were included in the model: flexor pollicis longus (FPL, extensor pollicis longus (EPL, extensor pollicis brevis (EPB, abductor pollicis longus (APL, flexor pollicis brevis (FPB, abductor pollicis brevis (APB, the transverse head of the adductor pollicis (ADPt, the oblique head of the adductor pollicis (ADPo, and opponens pollicis (OPP. Numerical tests were performed using an inverse dynamic approach. The joints were prescribed to an angular motion at one degree-of-freedom (DOF each time with all other DOFs of the joints being mechanically constrained, while the muscle forces in response to the joint motions were predicted. The normal joint stiffness was assumed to be 0.05, 0.10, and 0.15 N m/rad for interphalangeal (IP, metacarpophalangeal (MCP, and carpometacarpal (CMC joint, respectively. The joint stiffness was assumed to increase by 50% and 100%, simulating the biomechanical consequences of OA. Results Our simulations indicated that the increase in joint stiffness induced substantial increases in muscle forces, especially in the EPL and FPL muscles in response to IP, MCP, or CMC extension/flexion motions. Conclusions Because the strength of the muscles in the fingers is limited, the muscles will not be able to overcome joint resistance if joint stiffness is increased to its limit due to OA. This may contribute to the reduced range of motion typically seen in OA.

  9. Hydroxyapatite-coated uncemented implants and peri-implant infection

    NARCIS (Netherlands)

    Oosterbos, Cornelis Johannes Maria

    2004-01-01

    One of the major complications of joint replacement surgery is a peri-implant infection. A hip prosthesis coated with hydroxyapatite, a calcium phosphate (found in human bone), may offer protection in this respect. In a series of patients who were treated with a hydroxyapatite-coated hip prosthesis

  10. Instrumented hip implants: electric supply systems.

    Science.gov (United States)

    Soares dos Santos, Marco P; Ferreira, Jorge A F; Ramos, A; Simões, José A O; Morais, Raul; Silva, Nuno M; Santos, Paulo M; Reis, M J C S; Oliveira, T

    2013-10-18

    Instrumented hip implants were proposed as a method to monitor and predict the biomechanical and thermal environment surrounding such implants. Nowadays, they are being developed as active implants with the ability to prevent failures by loosening. The generation of electric energy to power active mechanisms of instrumented hip implants remains a question. Instrumented implants cannot be implemented without effective electric power systems. This paper surveys the power supply systems of seventeen implant architectures already implanted in-vivo, namely from instrumented hip joint replacements and instrumented fracture stabilizers. Only inductive power links and batteries were used in-vivo to power the implants. The energy harvesting systems, which were already designed to power instrumented hip implants, were also analyzed focusing their potential to overcome the disadvantages of both inductive-based and battery-based power supply systems. From comparative and critical analyses of the methods to power instrumented implants, one can conclude that: inductive powering and batteries constrain the full operation of instrumented implants; motion-driven electromagnetic energy harvesting is a promising method to power instrumented passive and active hip implants. PMID:24050511

  11. Cochlear Implants

    Science.gov (United States)

    ... on this topic can be found in our Audiology Information Series [PDF]. How does a cochlear implant ... speech-language pathologists; speech, language, and hearing scientists; audiology and speech-language pathology support personnel; and students. ...

  12. The comparison of modified Lejour method and the traditional double-ring periareolar incisions joint breast implants technique for the correction of mastoptosis%改良Lejour法与传统双环法联合假体矫正乳房下垂方法比较

    Institute of Scientific and Technical Information of China (English)

    吴振; 贺洁; 周蔚; 付莹莹; 徐岩; 王大勇

    2015-01-01

    目的:对乳房提升术改良Lejour法的效果予以评价,并与传统双环法联合假体矫正乳房下垂的效果进行比较.方法:对1例乳房下垂患者,先用传统双环法联合假体进行矫正,效果改善不明显而瘢痕明显,术后半年采用改良Lejour法,重塑乳房外观.结果:术后随访3个月,采用改良Lejour法后切口瘢痕不明显,满意度高.结论:本例乳房松弛明显,就本例而言,采用改良Lejour法比传统双环法联合假体矫正乳房下垂效果要好,术后乳房形态好、瘢痕轻.%Objective To evaluate the effect of modified Lejour method for breast lift,and to compare with the traditional double-ring periareolar incisions joint breast implants technique for the correction of mastoptosis. Methods The patient had received treatment with the traditional double-ring periareolar incisions joint breast implants technique for the correction of mastoptosis six months ago, the effects are not ideal and the scar of incision are obvious.Now we reshaped the breast appearance by modified Lejour method. Results The patient was followed up for 3 months,we found that the scar were not obvious,and the patient was high satisfied. Conclusion In this case,the patient with severe mastoptosis received better effects by modified Lejour method compared with the traditional double-ring periareolar incisions joint breast implants technique,the appearance of breast are ideal and there are less scar.

  13. Joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret......Afhandlingen analysere de konkurrenceretlige og selskabsretlige regler som er bestemmende for hvordan et joint venture samarbejde er struktureret...

  14. Joint ventures

    NARCIS (Netherlands)

    M.N. Hoogendoorn (Martin)

    2009-01-01

    textabstractEen veel voorkomende wijze van samenwerking tussen ondernemingen is het uitvoeren van activiteiten in de vorm van een joint venture. Een joint venture is bijna altijd een afzonderlijke juridische entiteit. De partners in de joint venture voeren gezamenlijk de zeggenschap uit. In internat

  15. Coracoclavicular joint

    International Nuclear Information System (INIS)

    The coracoclvicular joint, a rear abnormality which may be the cause of pain in the shoulder and limitation of motion of the shoulder joint, is discussed. A case of coracoclvicular joint with shoulder pain was observed in 65 yrs old Korean male

  16. Cochlear Implant

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this text, the authors recall the main principles and data ruling cochlear implants. Then, a first circle of technical equipment for assistance is presented. This circle includes: device setting (DS), Electrically evoked Auditory Brainstem Responses (EABR), Neural Response Telemetry (NRT), Stapedial Reflex (SR) and Electrodogram Acquisition (EA). This first cycle becomes more and more important as children are implanted younger and younger; the amount of data available with this assistance makes necessary the use of models (implicit or explicit) to handle this information. Consequently, this field is more open than ever.

  17. MR Imaging of Knee Arthroplasty Implants.

    Science.gov (United States)

    Fritz, Jan; Lurie, Brett; Potter, Hollis G

    2015-01-01

    Primary total knee arthroplasty is a highly effective treatment that relieves pain and improves joint function in a large percentage of patients. Despite an initially satisfactory surgical outcome, pain, dysfunction, and implant failure can occur over time. Identifying the etiology of complications is vital for appropriate management and proper timing of revision. Due to the increasing number of knee arthroplasties performed and decreasing patient age at implantation, there is a demand for accurate diagnosis to determine appropriate treatment of symptomatic joints following knee arthroplasty, and for monitoring of patients at risk. Magnetic resonance (MR) imaging allows for comprehensive imaging evaluation of the tissues surrounding knee arthroplasty implants with metallic components, including the polyethylene components. Optimized conventional and advanced pulse sequences can result in substantial metallic artifact reduction and afford improved visualization of bone, implant-tissue interfaces, and periprosthetic soft tissue for the diagnosis of arthroplasty-related complications. In this review article, we discuss strategies for MR imaging around knee arthroplasty implants and illustrate the imaging appearances of common modes of failure, including aseptic loosening, polyethylene wear-induced synovitis and osteolysis, periprosthetic joint infections, fracture, patellar clunk syndrome, recurrent hemarthrosis, arthrofibrosis, component malalignment, extensor mechanism injury, and instability. A systematic approach is provided for evaluation of MR imaging of knee implants. MR imaging with optimized conventional pulse sequences and advanced metal artifact reduction techniques can contribute important information for diagnosis, prognosis, risk stratification, and surgical planning. PMID:26295591

  18. Cochlear Implants

    Science.gov (United States)

    ... an optimal period to develop speech and language skills. Research has shown that when these children receive a cochlear implant followed by intensive therapy before they are 18 months ... age develop language skills at a rate comparable to children with normal ...

  19. Dental Implants

    Medline Plus

    Full Text Available ... suffer from social consequences and poor nutrition. Rebuilding Bone When the supporting alveolar bone melts away , it’s gone for good, but through grafting, a skilled dental professional can recreate bone to fuse with and support an implant. This ...

  20. Cochlear implant

    Science.gov (United States)

    ... are sent along the auditory nerve to the brain. A deaf person does not have a functioning inner ear. A cochlear implant tries to replace the function of the inner ear by ... signals to the brain. Sound is picked up by a microphone worn ...

  1. Dental Implants

    Medline Plus

    Full Text Available Dental Implants A fuller, more complete smile is within reach. The following information is designed to provide helpful facts so you ... found in nature. What Happens When You Lose a Tooth? When you lose a tooth, especially a ...

  2. Dental Implants

    Medline Plus

    Full Text Available ... an implant connects directly to the jaw bone. It’s obviously not the same as the original connection , ... may feel you don’t need to replace it, since no one can see that it’s missing ...

  3. Standardized Loads Acting in Hip Implants.

    Directory of Open Access Journals (Sweden)

    Georg Bergmann

    Full Text Available With the increasing success of hip joint replacements, the average age of patients has decreased, patients have become more active and their expectations of the implant durability have risen. Thus, pre-clinical endurance tests on hip implants require defining realistic in vivo loads from younger and more active patients. These loads require simplifications to be applicable for simulator tests and numerical analyses. Here, the contact forces in the joint were measured with instrumented hip implants in ten subjects during nine of the most physically demanding and frequent activities of daily living. Typical levels and directions of average and high joint loads were extracted from the intra- and inter-individually widely varying individual data. These data can also be used to analyse bone remodelling at the implant-bone interface, evaluate tissue straining in finite element studies or validate analytical loading predictions, among other uses. The current ISO standards for endurance tests of implant stems and necks are based on historic analytical data from the 1970s. Comparisons of these test forces with in vivo loads unveiled that their unidirectional orientations deviate from the time-dependent in vivo directions during walking and most other activities. The ISO force for testing the stem is substantially too low while the ISO force for the neck better matches typical in vivo magnitudes. Because the magnitudes and orientations of peak forces substantially vary among the activities, load scenarios that reflect a collection of time-dependent high forces should be applied rather than using unidirectional forces. Based on data from ten patients, proposals for the most demanding activities, the time courses of the contact forces and the required cycle numbers for testing are given here. Friction moments in the joint were measured in addition to the contact forces. The moment data were also standardized and can be applied to wear tests of the implant

  4. Standardized Loads Acting in Hip Implants.

    Science.gov (United States)

    Bergmann, Georg; Bender, Alwina; Dymke, Jörn; Duda, Georg; Damm, Philipp

    2016-01-01

    With the increasing success of hip joint replacements, the average age of patients has decreased, patients have become more active and their expectations of the implant durability have risen. Thus, pre-clinical endurance tests on hip implants require defining realistic in vivo loads from younger and more active patients. These loads require simplifications to be applicable for simulator tests and numerical analyses. Here, the contact forces in the joint were measured with instrumented hip implants in ten subjects during nine of the most physically demanding and frequent activities of daily living. Typical levels and directions of average and high joint loads were extracted from the intra- and inter-individually widely varying individual data. These data can also be used to analyse bone remodelling at the implant-bone interface, evaluate tissue straining in finite element studies or validate analytical loading predictions, among other uses. The current ISO standards for endurance tests of implant stems and necks are based on historic analytical data from the 1970s. Comparisons of these test forces with in vivo loads unveiled that their unidirectional orientations deviate from the time-dependent in vivo directions during walking and most other activities. The ISO force for testing the stem is substantially too low while the ISO force for the neck better matches typical in vivo magnitudes. Because the magnitudes and orientations of peak forces substantially vary among the activities, load scenarios that reflect a collection of time-dependent high forces should be applied rather than using unidirectional forces. Based on data from ten patients, proposals for the most demanding activities, the time courses of the contact forces and the required cycle numbers for testing are given here. Friction moments in the joint were measured in addition to the contact forces. The moment data were also standardized and can be applied to wear tests of the implant. It was shown that

  5. Cochlear implants

    OpenAIRE

    Despotović, Adrijana

    2011-01-01

    The aim of the thesis is to analyze the performance of the child with cochlear implant (CI) at language, math and movement activities. For the purpose of research exercises from all three above mentioned activities are prepared. Results of the exercises constitute the ground for the comparison of a child with CI and children with no hearing disability. Testing language skills was performed with exercises that included understanding, diction and identifying syllables. Mathematic skills...

  6. Hand osteoarthritis: Differential diagnosis with inflammatory joint diseases and treatment policy

    Directory of Open Access Journals (Sweden)

    Yu. A. Olyunin

    2015-01-01

    Full Text Available Osteoarthritis (OA usually affects certain joint groups selectively and the hand joints (HJ are one of its classical locations. Hand OA is widespread in the population. In their practice rheumatologists encounter HJ injury in OA in 38% of cases. It is conventional to identify three main types of hand OA. These are 1 interphalangeal OA that may or may not be accompanied by nodulation; 2 first carpometacarpal OA; and 3 erosive OA. At the same time, the rate of clinical forms ranges from 2.0 to 6.2%; it is 4.7 to 20.4% in the elderly. Nonsteroidal antiinflammatory drugs (NSAIDs are most commonly used to relieve pain that is the main manifestation of the disease. The risk for NSAID-related adverse gastrointestinal (GI events is substantially reduced by the drugs that exert their effects mainly on cyclooxygenase 2. These include nimesulide in particular. Undesirable GI effects may be also considerably minimized by using NSAIDs that have both their gastroprotective and antiinflammatory activities. By suppressing pain and inflammatory changes, the recently designed NSAID amtolmetin guacil simultaneously exerts a protective effect on the GI mucosa, by elevating its nitric oxide levels.

  7. 21 CFR 872.3940 - Total temporomandibular joint prosthesis.

    Science.gov (United States)

    2010-04-01

    ... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3940 Total temporomandibular joint... implanted in the human jaw to replace the mandibular condyle and augment the glenoid fossa to...

  8. Risk factors of peri-implant pathology.

    Science.gov (United States)

    de Araújo Nobre, Miguel; Mano Azul, António; Rocha, Evangelista; Maló, Paulo

    2015-06-01

    This study aimed to identify risk factors for the incidence of peri-implant pathology. One-thousand, two-hundred and seventy-fifty patients (255 cases and 1020 controls), rehabilitated with dental implants, were included. Peri-implant pathology was defined as the presence of peri-implant pockets ≥ 5 mm, bleeding on probing, vertical bone loss, and loss of attachment ≥ 2 mm. Cases and controls were matched for age, gender, and duration of follow-up. A logistic regression model was used, with estimation of the OR for each variable and interaction, with a level of significance of 5%. The risk factors for peri-implant pathology were: history of periodontitis (OR = 19), bacterial plaque (OR = 3.6), bleeding (OR = 2.9), bone level on the medium third of the implant (OR = 13.9), lack of prosthetic fit or non-optimal screw joint (OR = 5.9), metal-ceramic restorations (OR = 3.9), and the interaction between bacterial plaque and the proximity of other teeth or implants (PROXI) (OR = 4.3). PROXI (OR = 0.44) exerted a protective effect when independent. Based on the results, peri-implant pathology represents a group of multifactorial situations with interaction of biological and biomechanical components in its pathogenesis. It was possible to model the condition and to assess, with high precision, the risk profile of each patient. PMID:25894059

  9. Cochlear Implant

    Directory of Open Access Journals (Sweden)

    Mehrnaz Karimi

    1992-04-01

    Full Text Available People with profound hearing loss are not able to use some kinds of conventional amplifiers due to the nature of their loss . In these people, hearing sense is stimulated only when the auditory nerve is activated via electrical stimulation. This stimulation is possible through cochlear implant. In fact, for the deaf people who have good mental health and can not use surgical and medical treatment and also can not benefit from air and bone conduction hearing aids, this device is used if they have normal central auditory system. The basic parts of the device included: Microphone, speech processor, transmitter, stimulator and receiver, and electrode array.

  10. Breast reconstruction - implants

    Science.gov (United States)

    Breast implants surgery ... wait 1 to 3 months before the permanent breast implant is placed during the second stage. In the ... from your chest and replaces it with a breast implant. This surgery takes 1 to 2 hours. Before ...

  11. Implantable Cardioverter Defibrillator

    Science.gov (United States)

    ... NHLBI on Twitter. What Is an Implantable Cardioverter Defibrillator? An implantable cardioverter defibrillator (ICD) is a small ... pacemakers and defibrillators. Comparison of an Implantable Cardioverter Defibrillator and a Pacemaker The image compares an ICD ...

  12. Nanotechnology and Dental Implants

    OpenAIRE

    Sandrine Lavenus; Guy Louarn; Pierre Layrolle

    2010-01-01

    The long-term clinical success of dental implants is related to their early osseointegration. This paper reviews the different steps of the interactions between biological fluids, cells, tissues, and surfaces of implants. Immediately following implantation, implants are in contact with proteins and platelets from blood. The differentiation of mesenchymal stem cells will then condition the peri-implant tissue healing. Direct bone-to-implant contact is desired for a biomechanical anchoring of i...

  13. Complications after cardiac implantable electronic device implantations

    DEFF Research Database (Denmark)

    Kirkfeldt, Rikke Esberg; Johansen, Jens Brock; Nohr, Ellen Aagaard;

    2013-01-01

    Complications after cardiac implantable electronic device (CIED) treatment, including permanent pacemakers (PMs), cardiac resynchronization therapy devices with defibrillators (CRT-Ds) or without (CRT-Ps), and implantable cardioverter defibrillators (ICDs), are associated with increased patient...

  14. Joint pain

    Science.gov (United States)

    ... or conditions. It may be linked to arthritis , bursitis , and muscle pain . No matter what causes it, ... Autoimmune diseases such as rheumatoid arthritis and lupus Bursitis Chondromalacia patellae Crystals in the joint: gout (especially ...

  15. Estudo comparativo entre ressecção do trapézio e interposição tendinosa com e sem ligamentoplastia no tratamento da artrose carpometacarpiana do polegar Comparative study between trapezium resection and tendon interposition with and without ligament plasty in the management of carpometacarpal arthrosis of the thumb

    Directory of Open Access Journals (Sweden)

    Arlindo Gomes Pardini Junior

    2008-03-01

    opponency, movements of the metacarpophalangeal joint, pinching and pressure strength, radiographic measurement of the distance between the first metacarpian and the scaphoid, and measurement of the angle between the first and the second metacarpian. Subjective evaluation was done with a DASH questionnaire, an analogical-digital scale to evaluate pain and patient satisfaction. RESULTS AND CONCLUSION: After application of the criteria described and using Student t test for statistical analysis, the authors concluded that the ligament reconstruction has no advantage over the simple tendon interposition in carpometacarpal arthrosis of the thumb.

  16. Standardized loads acting in knee implants.

    Science.gov (United States)

    Bergmann, Georg; Bender, Alwina; Graichen, Friedmar; Dymke, Jörn; Rohlmann, Antonius; Trepczynski, Adam; Heller, Markus O; Kutzner, Ines

    2014-01-01

    The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I) average body weight and average load levels and II) high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372-4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure.

  17. Standardized loads acting in knee implants.

    Directory of Open Access Journals (Sweden)

    Georg Bergmann

    Full Text Available The loads acting in knee joints must be known for improving joint replacement, surgical procedures, physiotherapy, biomechanical computer simulations, and to advise patients with osteoarthritis or fractures about what activities to avoid. Such data would also allow verification of test standards for knee implants. This work analyzes data from 8 subjects with instrumented knee implants, which allowed measuring the contact forces and moments acting in the joint. The implants were powered inductively and the loads transmitted at radio frequency. The time courses of forces and moments during walking, stair climbing, and 6 more activities were averaged for subjects with I average body weight and average load levels and II high body weight and high load levels. During all investigated activities except jogging, the high force levels reached 3,372-4,218N. During slow jogging, they were up to 5,165N. The peak torque around the implant stem during walking was 10.5 Nm, which was higher than during all other activities including jogging. The transverse forces and the moments varied greatly between the subjects, especially during non-cyclic activities. The high load levels measured were mostly above those defined in the wear test ISO 14243. The loads defined in the ISO test standard should be adapted to the levels reported here. The new data will allow realistic investigations and improvements of joint replacement, surgical procedures for tendon repair, treatment of fractures, and others. Computer models of the load conditions in the lower extremities will become more realistic if the new data is used as a gold standard. However, due to the extreme individual variations of some load components, even the reported average load profiles can most likely not explain every failure of an implant or a surgical procedure.

  18. Implant success!!!.....simplified

    OpenAIRE

    Luthra Kaushal

    2009-01-01

    The endeavor towards life-like restoration has helped nurture new vistas in the art and science of implant dentistry. The protocol of “restoration-driven implant placement” ensures that the implant is an apical extension of the ideal future restoration and not the opposite. Meticulous pre-implant evaluation of soft and hard tissues, diagnostic cast and use of aesthetic wax-up and radiographic template combined with surgical template can simplify the intricate roadmap for appropriate implant t...

  19. Partial arthroscopic trapeziectomy with ligament reconstruction to treat primary thumb basal joint osteoarthritis.

    Science.gov (United States)

    Desmoineaux, P; Delaroche, C; Beaufils, P

    2012-11-01

    Since the outcome of partial trapeziectomy is not always satisfactory, we proposed using arthroscopy to perform partial trapeziectomy and to perform ligament reconstruction with the abductor pollicis longus tendon. A tendon strip was left intact at its insertion at the base of the first metacarpal and then slipped into the trapeziectomy space. It was fixed into a blind tunnel at the base of the second metacarpal with a bioabsorbable interference screw. Forty-nine patients were surgically treated between 2006 and 2009. With an average follow-up of 3.6 years, 83.5% of patients were satisfied with the procedure; 96% of thumbs were stable and 74% were pain free. The average recovery time was 4.5 months. There were four cases of radial nerve branch irritation and one case of flexor carpi radialis tendinitis; there were no cases of complex regional pain syndrome. This minimally-invasive technique is a less-aggressive treatment approach for thumb carpometacarpal joint arthritis, which simplify postoperative recovery. PMID:23098774

  20. Considerations upon applying tripodic coupling in artificial hip joint

    Science.gov (United States)

    Alaci, S.; Ciornei, M. C.; Filote, C.; Ciornei, F. C.; Gradinariu, M. C.

    2016-08-01

    The employment of tripodic joint allows creation of homokinetical transmissions and thus it is expected that at the use of such a transmission for a dynamical system with smooth enough inputs, the outputs should maintain the same characteristics. The present paper presents a comparison between the effect of using a spherical joint in spatial mechanisms - the classical solution for hip joint implant, and the effect of replacing such prosthesis with a tripodic coupling.

  1. Joint purpose?

    DEFF Research Database (Denmark)

    Pristed Nielsen, Helene

    2013-01-01

    Starting from Crenshaw´s point that antiracism often fails to interrogate patriarchy and that feminism often reproduces racist practices (1991: 1252), this paper asks: What are the theoretical reasons for believing that feminism and anti-racism can be regarded as fighting for the joint purpose of...

  2. Joint imaging

    International Nuclear Information System (INIS)

    Joint imaging is a proven diagnostic procedure which has become indispensable to the detection and treatment of different joint diseases in almost all disciplines. The method is suited for early diagnosis of joint affections both in soft tissue and bone which cannot be detected by X-ray or other procedures. The local activity accumulation depends on the rate of metabolism and is visualized in the scan, which in turn enables the extension and floridity of focal lesions to be evaluated and followed-up. Although joint scans may often give hints to probabilities relevant to differential diagnosis, the method is non-specific and only useful if based on the underlying clinical picture and X-ray finding, if possible. The radiation exposure is very low and does not represent a hazard in cases of adequate assessment of indication. In pregnant women and children the assessment of indication has to be based on very strict principles. The method is suited for out-patient diagnosis and can be applied in all installations equipped with a gamma camera and a technetium generator. (orig.)

  3. The manufacture of generic replicas of implants for arthroplasty of the hip and knee: is it regulated and will it save money?

    Science.gov (United States)

    Atrey, A; Heylen, S; Gosling, O; Porteous, M J L; Haddad, F S

    2016-07-01

    Joint replacement of the hip and knee remain very satisfactory operations. They are, however, expensive. The actual manufacturing of the implant represents only 30% of the final cost, while sales and marketing represent 40%. Recently, the patents on many well established and successful implants have expired. Companies have started producing and distributing implants that purport to replicate existing implants with good long-term results. The aims of this paper are to assess the legality, the monitoring and cost saving implications of such generic implants. We also assess how this might affect the traditional orthopaedic implant companies. Cite this article: Bone Joint J 2016;98-B:892-900. PMID:27365466

  4. Implant success!!!.....simplified

    Directory of Open Access Journals (Sweden)

    Luthra Kaushal

    2009-01-01

    Full Text Available The endeavor towards life-like restoration has helped nurture new vistas in the art and science of implant dentistry. The protocol of "restoration-driven implant placement" ensures that the implant is an apical extension of the ideal future restoration and not the opposite. Meticulous pre-implant evaluation of soft and hard tissues, diagnostic cast and use of aesthetic wax-up and radiographic template combined with surgical template can simplify the intricate roadmap for appropriate implant treatment. By applying the harmony of artistic skill, scientific knowledge and clinical expertise, we can simply master the outstanding implant success in requisites of aesthetics, phonetics and function.

  5. New approach to orthopedic implant design

    Energy Technology Data Exchange (ETDEWEB)

    Hollerbach, K; Perfect, S; Martz, H; Ashby, E

    1999-07-03

    This report describes the accomplishments of a three year LDRD project, aimed at developing computational models and methodologies for improving prosthetic joint design. The investigators developed human models as well as prosthetic joint models. Input data came both from high resolution scans performed at Lawrence Livermore National Laboratory (LLNL) and from data provided by collaborators. Results of the approach, in addition to being presented at scientific meetings, are being used to obtain US Food and Drug Administration (FDA) approval in the process of putting new implant designs on the market.

  6. Morse taper dental implants and platform switching: The new paradigm in oral implantology

    Science.gov (United States)

    Macedo, José Paulo; Pereira, Jorge; Vahey, Brendan R.; Henriques, Bruno; Benfatti, Cesar A. M.; Magini, Ricardo S.; López-López, José; Souza, Júlio C. M.

    2016-01-01

    The aim of this study was to conduct a literature review on the potential benefits with the use of Morse taper dental implant connections associated with small diameter platform switching abutments. A Medline bibliographical search (from 1961 to 2014) was carried out. The following search items were explored: “Bone loss and platform switching,” “bone loss and implant-abutment joint,” “bone resorption and platform switching,” “bone resorption and implant-abutment joint,” “Morse taper and platform switching.” “Morse taper and implant-abutment joint,” Morse taper and bone resorption,” “crestal bone remodeling and implant-abutment joint,” “crestal bone remodeling and platform switching.” The selection criteria used for the article were: meta-analysis; randomized controlled trials; prospective cohort studies; as well as reviews written in English, Portuguese, or Spanish languages. Within the 287 studies identified, 81 relevant and recent studies were selected. Results indicated a reduced occurrence of peri-implantitis and bone loss at the abutment/implant level associated with Morse taper implants and a reduced-diameter platform switching abutment. Extrapolation of data from previous studies indicates that Morse taper connections associated with platform switching have shown less inflammation and possible bone loss with the peri-implant soft tissues. However, more long-term studies are needed to confirm these trends. PMID:27011755

  7. Failures of the RM finger prosthesis joint replacement system.

    Science.gov (United States)

    Middleton, A; Lakshmipathy, R; Irwin, L R

    2011-09-01

    In our unit a high failure rate of the RM finger prosthesis joint replacement system was noted, prompting a review of cases. A series of patients underwent implantation under the care of one surgeon and the results were monitored. Twenty-one devices were implanted of which 16 were inserted for rheumatoid disease. Patients were reviewed regularly and the implant performance was assessed critically along with survival of the implant to revision, infection or death of the patient. The mean follow-up was 32 months. Unacceptable failure rates at early and medium term stages were identified, with 15 of the implants revised by 2 years. Loosening was the commonest mode of failure. The authors do not recommend the use of this implant, especially in cases of rheumatoid arthritis.

  8. Urinary incontinence - injectable implant

    Science.gov (United States)

    Injectable implants are injections of material into the urethra to help control urine leakage ( urinary incontinence ) caused by a ... into the tissue next to the sphincter. The implant procedure is usually done in the hospital. Or ...

  9. Implantable cardioverter defibrillator - discharge

    Science.gov (United States)

    ... medlineplus.gov/ency/patientinstructions/000108.htm Implantable cardioverter defibrillator - discharge To use the sharing features on this ... chest wall. A device called an implantable cardioverter-defibrillator (ICD) was inserted under your skin and muscle. ...

  10. Pacemakers and Implantable Defibrillators

    Science.gov (United States)

    ... need a cardiac pacemaker or an implantable cardioverter defibrillator (ICD). They are devices that are implanted in ... can act as both a pacemaker and a defibrillator. Many ICDs also record the heart's electrical patterns ...

  11. Implantable cardioverter-defibrillator

    Science.gov (United States)

    ... medlineplus.gov/ency/article/007370.htm Implantable cardioverter-defibrillator To use the sharing features on this page, please enable JavaScript. An implantable cardioverter-defibrillator (ICD) is a device that detects any life- ...

  12. Intracochlear misdirected implantation of a cochlear implant

    NARCIS (Netherlands)

    Tange, R A; Grolman, W; Maat, A

    2006-01-01

    This paper discusses a rare complication of an intracochlear misdirection of the electrode of a cochlear implant in a 55-year-old male. The patient received a cochlear implant using the mastoid-saving surgical approach. Intraoperative measurements showed impedance and NRT reactions suggesting a reas

  13. Implantable electronic medical devices

    CERN Document Server

    Fitzpatrick, Dennis

    2014-01-01

    Implantable Electronic Medical Devices provides a thorough review of the application of implantable devices, illustrating the techniques currently being used together with overviews of the latest commercially available medical devices. This book provides an overview of the design of medical devices and is a reference on existing medical devices. The book groups devices with similar functionality into distinct chapters, looking at the latest design ideas and techniques in each area, including retinal implants, glucose biosensors, cochlear implants, pacemakers, electrical stimulation t

  14. Principles of human joint replacement design and clinical application

    CERN Document Server

    Buechel, Frederick F

    2015-01-01

    This book is written for the users and designers of joint replacements. In its second extended edition it conveys to the reader the knowledge accumulated by the authors during their forty year effort on the development of replacement devices for the lower limb for the purpose of aiding the reader in their design and evaluation of joint replacement devices. The early chapters describe the engineering, scientific and medical principles needed for replacement joint evaluation. One must understand the nature and performance of the materials involved and their characteristics in vivo, i.e. the response of the body to implant materials. It is also essential to understand the response of the implants to applied loading and motion, particularly in the hostile physiological environment. A chapter describes the design methodology now required for joint replacement in the USA and EU countries. The remaining chapters provide a history of joint replacement, an evaluation of earlier and current devices and sample case hist...

  15. Antibacterial Surface Treatment for Orthopaedic Implants

    Directory of Open Access Journals (Sweden)

    Jiri Gallo

    2014-08-01

    Full Text Available It is expected that the projected increased usage of implantable devices in medicine will result in a natural rise in the number of infections related to these cases. Some patients are unable to autonomously prevent formation of biofilm on implant surfaces. Suppression of the local peri-implant immune response is an important contributory factor. Substantial avascular scar tissue encountered during revision joint replacement surgery places these cases at an especially high risk of periprosthetic joint infection. A critical pathogenic event in the process of biofilm formation is bacterial adhesion. Prevention of biomaterial-associated infections should be concurrently focused on at least two targets: inhibition of biofilm formation and minimizing local immune response suppression. Current knowledge of antimicrobial surface treatments suitable for prevention of prosthetic joint infection is reviewed. Several surface treatment modalities have been proposed. Minimizing bacterial adhesion, biofilm formation inhibition, and bactericidal approaches are discussed. The ultimate anti-infective surface should be “smart” and responsive to even the lowest bacterial load. While research in this field is promising, there appears to be a great discrepancy between proposed and clinically implemented strategies, and there is urgent need for translational science focusing on this topic.

  16. Antibacterial surface treatment for orthopaedic implants.

    Science.gov (United States)

    Gallo, Jiri; Holinka, Martin; Moucha, Calin S

    2014-08-11

    It is expected that the projected increased usage of implantable devices in medicine will result in a natural rise in the number of infections related to these cases. Some patients are unable to autonomously prevent formation of biofilm on implant surfaces. Suppression of the local peri-implant immune response is an important contributory factor. Substantial avascular scar tissue encountered during revision joint replacement surgery places these cases at an especially high risk of periprosthetic joint infection. A critical pathogenic event in the process of biofilm formation is bacterial adhesion. Prevention of biomaterial-associated infections should be concurrently focused on at least two targets: inhibition of biofilm formation and minimizing local immune response suppression. Current knowledge of antimicrobial surface treatments suitable for prevention of prosthetic joint infection is reviewed. Several surface treatment modalities have been proposed. Minimizing bacterial adhesion, biofilm formation inhibition, and bactericidal approaches are discussed. The ultimate anti-infective surface should be "smart" and responsive to even the lowest bacterial load. While research in this field is promising, there appears to be a great discrepancy between proposed and clinically implemented strategies, and there is urgent need for translational science focusing on this topic.

  17. Intra-articular distribution pattern after ultrasound-guided injections in wrist joints of patients with rheumatoid arthritis

    Energy Technology Data Exchange (ETDEWEB)

    Boesen, Mikael [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)], E-mail: parker@frh.regioh.dk; Jensen, Karl Erik [State Hospital, Department of Radiology, MRI Division, Copenhagen (Denmark)], E-mail: karl.erik.Jensen@rh.regionh.dk; Torp-Pedersen, Soren [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark); Cimmino, Marco A. [Rheumatologic Clinic, Department of Internal Medicine, University of Genoa (Italy)], E-mail: cimmino@unige.it; Danneskiold-Samsoe, Bente; Bliddal, Henning [Parker Institute, Frederiksberg Hospital, Nordre Fasanvej 57, 2000 Frederiksberg, Copenhagen (Denmark)

    2009-02-15

    Objective: To investigate the distribution of an ultrasound-guided intra-articular (IA) injection in the wrist joint of patients with rheumatoid arthritis (RA). Methods: An ultrasound-guided IA drug injection into the wrist joint was performed in 17 patients with 1 ml methylprednisolone (40 mg/ml), 0.5 ml Lidocaine (5 mg/ml) and 0.15 ml gadolinium (Omniscan 0.5 mmol/ml). The drug solution was placed in the central proximal part of the wrist between the distal radius and the lunate bone. Coronal and axial MRI sequences were performed after the injection to visualize the distribution. Carpal distribution (radio-carpal, inter-carpal, and carpo-metacarpal) as well as radio-ulnar distribution was recorded. Full distribution in one compartment was given the value 1, partial distribution 0.5 and no distribution 0. A sum of the total distribution for all four compartments was calculated and correlated to the clinical parameters and the MRI OMERACT scores. Results: No uniform pattern was seen in the distribution of the contrast. Only two patients had full contrast distribution to all four compartments, and the mean distribution count for all patients was 2.4 (range 0.5-4). The distribution count correlated with the MRI OMERACT synovitis score (r = 0.60, p = 0.014), but not with the erosions, bonemarrow oedema scores or any clinical parameters. Conclusion: The distribution of contrast on MRI showed patient specific and random patterns after IA injections in active RA wrist joints. The degree of distribution increased with the MRI synovitis score, while no association was found with the erosion- and bonemarrow oedema score. These results indicate that a single injection into a standard injection site in the proximal part of the wrist cannot be assumed to distribute - and treat - the whole joint.

  18. Adhesive bone bonding prospects for lithium disilicate ceramic implants

    Science.gov (United States)

    Vennila Thirugnanam, Sakthi Kumar

    Temporomandibular Joint (TMJ) implants articulating mandible with temporal bone in humans have a very high failure rate. Metallic TMJ implants available in the medical market are not osseointegrated, but bond only by mechanical interlocking using screws which may fail, mandating a second surgery for removal. Stress concentration around fixture screws leads to aseptic loosening or fracture of the bone. It has been proposed that this problem can be overcome by using an all-ceramic TMJ implant bonded to bone with dental adhesives. Structural ceramics are promising materials with an excellent track record in the field of dentis.

  19. COCHLEAR IMPLANTATION: MY EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Shankar

    2015-12-01

    Full Text Available Cochlear implant is a small, surgically implanted complex electronic device that can help to provide a sense of sound to a person with severe to profound sensorineural hearing loss. This type of hearing loss, typically involves damage to hair cells in the cochlea, as a result sound cannot reach the auditory nerve which usually receives information from hair cells. A cochlear implant skips the damaged hair cells and to stimulate the auditory nerve directly. An implant does not restore normal hearing, instead it can give a deaf person a useful representation of sounds in the environment and help him or her to understand speech. I am here presenting this article in relation to the indications, intraoperative and postoperative complications of cochlear implantation in our institute since January 2013. Children who receive implants at earlier age, outperform their peers who are implanted at a later age. This is reflected in all the areas of speech and language development.

  20. Brandon Research, Inc. Orthopedic Implant Cooperative Research and Development Agreement (CRADA) Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, W.R.

    1999-04-22

    The project was a joint research effort between the U. S. Department of Energy's (DOE) Kansas City Plant (KCP) and Brandon Research, Inc. to develop ways to improve implants used for orthopedic surgery for joint replacement. The primary product produced by this study is design information, which may be used to develop implants that will improve long-term fixation and durability in the host bone environment.

  1. Benefits and Risks of Cochlear Implants

    Science.gov (United States)

    ... and Medical Procedures Implants and Prosthetics Cochlear Implants Benefits and Risks of Cochlear Implants Share Tweet Linkedin ... the Use of Cochlear Implants What are the Benefits of Cochlear Implants? For people with implants: Hearing ...

  2. Osteomyelitis of sternum and rib after breast prosthesis implantation: A rare or underestimated infection?

    Science.gov (United States)

    Seng, Piseth; Alliez, Antoine; Honnorat, Estelle; Menard, Amelie; Casanova, Dominique; Stein, Andreas

    2014-01-01

    Sternum and rib osteomyelitis complicated from breast implant infection is rare. We report a case of early sternum and rib osteomyelitis occurred during breast implant infection managed in an inter-regional referral center for bone/joint infections in the south of France. PMID:26793446

  3. Osteomyelitis of sternum and rib after breast prosthesis implantation: A rare or underestimated infection?

    Directory of Open Access Journals (Sweden)

    Piseth Seng

    2015-01-01

    Full Text Available Sternum and rib osteomyelitis complicated from breast implant infection is rare. We report a case of early sternum and rib osteomyelitis occurred during breast implant infection managed in an inter-regional referral center for bone/joint infections in the south of France.

  4. Bone compaction enhances fixation of weight-bearing hydroxyapatite-coated implants

    DEFF Research Database (Denmark)

    Kold, Søren; Rahbek, Ole; Vestermark, Marianne;

    2006-01-01

    The effect of bone compaction vs conventional drilling on the fixation of hydroxyapatite-coated implants was examined in a weight-bearing canine model. In each dog, one knee joint had the implant cavity prepared with drilling, the other with compaction. Eight dogs were euthanized after 2 weeks...

  5. Wear prediction of ceramic-on-ceramic hip artificial joints

    OpenAIRE

    Askari, E; Flores, Paulo; Dabirrahmani, D.; Appleyard, R.

    2015-01-01

    Wear can influence the lifetime and performance of implants and has been found to be a key factor in primary failure of artificial hip joints. The present study aims to present a spatial multibody dynamic model to predict wear in ceramic-on-ceramic hip implants. The problem was formulated by developing a spatial multibody dynamic model of a hip prosthesis taking three-dimensional physiological loading and motion of the human body into account. Then, the Archard wear model was inte...

  6. Implantes transcigomáticos Traszygomatic implants

    Directory of Open Access Journals (Sweden)

    B. Fernández Ateca

    2004-12-01

    Full Text Available Los implantes cigomáticos, originariamente diseñados por Branemark en 1989, son implantes de cabeza en 45 grados, de 4'5 milímetros de diámetro en su parte más ancha, y que pueden medir entre 30 y 50 milímetros de longitud. Se insertan desde la parte palatina del proceso alveolar, siguiendo la cresta cigomática-alveolar hasta anclarse en el cuerpo del malar, y en el caso de pacientes maxilectomizados, entrando directamente en el cuerpo del malar. Estos implantes ofrecen una alternativa más al cirujano en el momento de planificar un tratamiento protésico-rehabilitador implantosoportado. Sobretodo, en aquellos pacientes con un maxilar superior atrófico en el que no se pueden realizar injertos óseos o estos han fracasado. El objetivo de este artículo es proponer el protocolo quirúrgico de colocación de los implantes trascigomáticos y revisar la literatura actual sobre la evolución clínica de estos implantes.The zygomatic implants, originally designed by Branemark in 1989, are implants with a 45 degree inclined head, 4'5 millimetre diameter at their widest part and measuring between 30 and 50 millimetres in length. They are inserted from the palatine side of the alveolar process, following the zygomatic-alveolar edge and anchor in the body of the zygomatic bone. In the case of maxillectomized patients, they are inserted directly in the body of the malar bone. These implants offer an additional alternative to the surgeon when planning an implant supported rehabilitation treatment; specially in those patients with an atrophic maxilla in which osseous grafts cannot be realized or these grafts have failed. The objective of this article is to propose the surgical,protocol of placement of traszygomatic implants and to check the current literature on the clinical evolution of these implants.

  7. Local delivery of zoledronate from a poly (D,L-lactide)-Coating increases fixation of press-fit implants.

    Science.gov (United States)

    Jakobsen, Thomas; Bechtold, Joan E; Søballe, Kjeld; Jensen, Thomas; Greiner, Stefan; Vestermark, Marianne T; Baas, Jørgen

    2016-01-01

    Early secure fixation of total joint replacements is crucial for long-term survival. Antiresorptive agents such as bisphosphonates have been shown to increase implant fixation. We investigated whether local delivery of zoledronate from poly-D, L-lactide (PDLLA)-coated implants could improve implant fixation and osseointegration. Experimental titanium implants were bilaterally inserted press-fit into the proximal tibiae of 10 dogs. On one side the implant was coated with PDLLA containing zoledronate. The contralateral implant was uncoated and used as control. Observation period was 12 weeks. Implant fixation was evaluated with histomorphometry and biomechanical push-out test. We found an approximately twofold increase in all biomechanical parameters when comparing data from the zoledronate group with their respective controls. Histomorphometry showed increased amount of preserved bone and increased bone formation around the zoledronate implants. This study indicates that local delivery of zoledronate from a PDDLA coating has the potential to increase implant fixation. PMID:26177742

  8. Dental Implant Systems

    OpenAIRE

    Yoshiki Oshida; Tuna, Elif B.; Oya Aktören; Koray Gençay

    2010-01-01

    Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with...

  9. Temporary ectopic hand implantation

    Directory of Open Access Journals (Sweden)

    Xu Zhang

    2015-03-01

    Full Text Available Severe crushing injuries to the distal forearm can preclude immediate hand replantation, with temporary ectopic implantation as a practicable option under special circumstances. This report describes a case of temporary ectopic hand implantation for a crush injury extending from the wrist to the middle third of the forearm, using the left foot as the recipient site. The hand was replanted onto the left forearm 3 months after the ectopic implantation, with functional gains seen by 18 months. Satisfactory ambulation was retained, with no reported foot pain. Temporary ectopic implantation is a pragmatic alternative under select circumstances.

  10. Ion implantation technology

    CERN Document Server

    Downey, DF; Jones, KS; Ryding, G

    1993-01-01

    Ion implantation technology has made a major contribution to the dramatic advances in integrated circuit technology since the early 1970's. The ever-present need for accurate models in ion implanted species will become absolutely vital in the future due to shrinking feature sizes. Successful wide application of ion implantation, as well as exploitation of newly identified opportunities, will require the development of comprehensive implant models. The 141 papers (including 24 invited papers) in this volume address the most recent developments in this field. New structures and possible approach

  11. Principles of Human Joint Replacement Design and Clinical Application

    CERN Document Server

    Buechel, Frederick F

    2012-01-01

    Drs. Buechel, an orthopaedic surgeon, and Pappas, a professor of Mechanical Engineering, are the designers of several successful joint replacement systems. The most well-known of these is the pioneering LCS knee replacement. They have written this book for the users and designers of joint replacements. It is an attempt to convey to the reader the knowledge accumulated by the authors during their thirty five year effort on the development of replacement devices for the lower limb for the purpose of aiding the reader in their design and evaluation of joint replacement devices. The early chapters describe the engineering, scientific and medical principles needed for replacement joint evaluation. One must understand the nature and performance of the materials involved and their characteristics in vivo, i.e. the response of the body to implant materials. It is also essential to understand the response of the implants to applied loading and motion, particularly in the hostile physiological environment. A chapter de...

  12. Silver-based antibacterial surfaces for bone implants

    NARCIS (Netherlands)

    Necula, B.S.

    2013-01-01

    Total hip arthroplasty (THA) is the most effective and safest method for treating severe degenerative, post-traumatic and other diseases of the joints. With an aging population that is increasingly active, the use of biomedical implants will continue to rise. It is estimated that more than 1,000,000

  13. Early efficacy study of matrix-induced autologous chondrocyte implantation repairing knee joint cartilage injury%基质诱导自体软骨细胞移植修复膝关节软骨损伤的早期疗效

    Institute of Scientific and Technical Information of China (English)

    王庆; 黄华扬; 张涛; 郑小飞; 李凭跃; 沈洪园; 陈加荣

    2016-01-01

    目的:探讨基质诱导自体软骨细胞移植修复膝关节软骨损伤的可行性及早期疗效。方法回顾性分析2012年4月至2013年3月13例单侧膝关节局灶性软骨缺损患者资料,男11例,女2例;年龄19~37岁,平均27.5岁;膝关节软骨缺损面积2.3~7.5 cm2,平均4.2 cm2;国际软骨损伤修复协会(ICRS )分级为Ⅲ级3例,Ⅳ级10例,均出现膝关节疼痛症状[视觉模拟评分(visual analogue scale, VAS)>3分]。13例患者均使用基质诱导软骨细胞移植技术进行软骨细胞移植。术后进行规范化功能康复锻炼。结果术后随访1年,1例患者因术后6.5个月下楼梯时扭伤膝关节致半月板损伤行关节镜下半月板修补术而剔除该患者术后12个月的评分,以避免结果偏倚。膝关节活动度,术后3个月(123.1°±8.0°)较术前(135.4°±5.7°)减少,膝关节损伤和骨关节炎评分(knee injury and use osteoarthritis outcome score, KOOS)的5个子集均较术前降低,Lysholm评分[(65.7±9.4)分]较术前[(71.2±12.3)分]无明显变化,国际膝关节评分委员会评分(International Knee Documentation Committee, IKDC)[(26.1±3.9)分]较术前[(43.5±6.5)分]减少;术后6、12个月的膝关节活动度(136.1°±6.1°、135.1°±3.6°)、Lysholm评分[(80.6±9.6)分、(86.6±9.2)分]、IKDC评分[(53.3±5.8)分、(62.8±7.2)分]、KOOS评分均较术前明显提高。术后12个月软骨修复组织磁共振评分[(73.3±17.9)分]较术前[(51.5±12.6)分]明显提高。结论基质诱导自体软骨细胞移植技术可有效修复膝关节软骨损伤,改善膝关节功能,具有良好的近期疗效。%Objective To study the feasibility and early efficacy of matrix⁃induced autologous chondrocyte implantation repairing knee joint cartilage injury. Methods The Matrix⁃induced autologous chondrocyte implantation was used to repair knee joint

  14. Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures.

    Science.gov (United States)

    Watters, William; Rethman, Michael P; Hanson, Nicholas Buck; Abt, Elliot; Anderson, Paul A; Carroll, Karen C; Futrell, Harry C; Garvin, Kevin; Glenn, Stephen O; Hellstein, John; Hewlett, Angela; Kolessar, David; Moucha, Calin; O'Donnell, Richard J; O'Toole, John E; Osmon, Douglas R; Evans, Richard Parker; Rinella, Anthony; Steinberg, Mark J; Goldberg, Michael; Ristic, Helen; Boyer, Kevin; Sluka, Patrick; Martin, William Robert; Cummins, Deborah S; Song, Sharon; Woznica, Anne; Gross, Leeaht

    2013-03-01

    The Prevention of Orthopaedic Implant Infection in Patients Undergoing Dental Procedures evidence-based clinical practice guideline was codeveloped by the American Academy of Orthopaedic Surgeons (AAOS) and the American Dental Association. This guideline replaces the previous AAOS Information Statement, "Antibiotic Prophylaxis in Bacteremia in Patients With Joint Replacement," published in 2009. Based on the best current evidence and a systematic review of published studies, three recommendations have been created to guide clinical practice in the prevention of orthopaedic implant infections in patients undergoing dental procedures. The first recommendation is graded as Limited; this recommendation proposes that the practitioner consider changing the long-standing practice of routinely prescribing prophylactic antibiotic for patients with orthopaedic implants who undergo dental procedures. The second, graded as Inconclusive, addresses the use of oral topical antimicrobials in the prevention of periprosthetic joint infections. The third recommendation, a Consensus statement, addresses the maintenance of good oral hygiene.

  15. Life expectancy of modular Ti6Al4V hip implants: Influence of stress and environment

    DEFF Research Database (Denmark)

    Chandra, A.; Ryu, J.J.; Karra, P.;

    2011-01-01

    body weight, as well as proximity of the joint fluid to its iso-electric point play key roles in determining wear rates and associated life expectancies of modular hip implants. Sustained aeration of joint fluid, as well as proper tolerancing of mating surfaces, along with a proper choice of material...

  16. Reliability of Tubular Joints

    DEFF Research Database (Denmark)

    Sørensen, John Dalsgaard; Thoft-Christensen, Palle

    In this paper the preliminary results obtained by tests on tubular joints are presented. The joints are T-joints and the loading is static. It is the intention in continuation of these tests to perform tests on other types of joints (e.g. Y-joints) and also with dynamic loading. The purpose...... of the test is partly to obtain empirical data for the ultimate load-carrying capacity of tubular T-joints and partly to obtain some experience in performing tests with tubular joints. It is well known that tubular joints are usually designed in offshore engineering on the basis of empirical formulas obtained...

  17. Spacesuit mobility knee joints

    Science.gov (United States)

    Vykukal, H. C. (Inventor)

    1979-01-01

    Pressure suit mobility joints are for use in interconnecting adjacent segments of an hermetically sealed spacesuit in which low torques, low leakage and a high degree of reliability are required. Each of the joints is a special purpose joint characterized by substantially constant volume and low torque characteristics and includes linkages which restrain the joint from longitudinal distension and includes a flexible, substantially impermeable diaphragm of tubular configuration spanning the distance between pivotally supported annuli. The diaphragms of selected joints include rolling convolutions for balancing the joints, while various joints include wedge-shaped sections which enhance the range of motion for the joints.

  18. Implantable titanium nail traction between the jaw joint micro titanium plate internal ifxation in trea-ting jaw fracture%植入式钛钉颌间牵引联合微型钛板内固定在颌骨骨折治疗中的作用

    Institute of Scientific and Technical Information of China (English)

    叶珊珊

    2014-01-01

    Objective To study the implantable titanium nail traction between the jaw joint micro titanium plate internal fixation for the treatment of jaw fracture effect. Method From November 2012 to November 2012 treated 136 cases of jaw fracture patients as the research object, randomly divided into observation group and control group. Between the control group with the traditional jaw traction-dental arch splints;observation group with implantable titanium nail traction between the jaw joint micro titanium plate internal ifxation method. Compare two groups of treatment. Result Observation group and control group, no signiifcant difference (P>0.05), but the observation group of fracture healing time was (1.98±0.76) months, signiifcantly faster than the control group (3.62±1.25) months, and signiifcant difference, statistically signiifcant (P0.05), after the operation, both of the above indexes had varying degrees of change, various functions to improve observation group were signiifcantly better than the control group, and signiifcant difference, statistically signiifcant (P<0.01);postoperative observation group, ifne rate was 92.65%;compared to control group was 80.88%, postoperative both statistically signiifcant difference (P < 0.05). Conclusion Implantable titanium nail traction between the jaw joint micro titanium plate internal ifxation for jaw fractures of good curative effect, high cure rate, compared with the traditional operation method, the patient's chewing function, opening function recover quickly, facial symmetry, no deformity, has a certain clinical value.%目的:研究植入式钛钉颌间牵引联合微型钛板内固定对于颌骨骨折的治疗效果。方法将本院2012年11月至2013年11月收治的136例颌骨骨折患者作为研究对象,随机均分为观察组与对照组。对照组患者采用传统颌间牵引术-牙弓夹板治疗;观察组患者采用植入式钛钉颌间牵引联合微型钛板内固定治疗。比较两组患

  19. Implantable CMOS Biomedical Devices

    Directory of Open Access Journals (Sweden)

    Toshihiko Noda

    2009-11-01

    Full Text Available The results of recent research on our implantable CMOS biomedical devices are reviewed. Topics include retinal prosthesis devices and deep-brain implantation devices for small animals. Fundamental device structures and characteristics as well as in vivo experiments are presented.

  20. MUSIC AND COCHLEAR IMPLANTS

    Institute of Scientific and Technical Information of China (English)

    Mao Yitao; Xu Li

    2013-01-01

    Currently, most people with modern multichannel cochlear implant systems can understand speech in qui-et environment very well. However, studies in recent decades reported a lack of satisfaction in music percep-tion with cochlear implants. This article reviews the literature on music ability of cochlear implant users by presenting a systematic outline of the capabilities and limitations of cochlear implant recipients with regard to their music perception as well as production. The review also evaluates the similarities and differences be-tween electric hearing and acoustic hearing regarding music perception. We summarize the research results in terms of the individual components of music (e.g., rhythm, pitch, and timbre). Finally, we briefly intro-duce the vocal singing of prelingually-deafened children with cochlear implants as evaluated by acoustic measures.

  1. Metallic implants and exposure to radiofrequency radiation

    International Nuclear Information System (INIS)

    There is increasing use of radiofrequency radiation (RFR) in industry for communications, welding, security, radio, medicine, navigation etc. It has been recognised for some years that RFR may interact with cardiac pacemakers and steps have been taken to prevent this interference. It is less well recognised that other metallic implants may also act as antennas in an RFR field and possibly cause adverse health effects by heating local tissues. There are a large and increasing number of implants having metal components which may be found in RFR workers. These implants include artificial joints, rods and plates used in orthopaedics, rings in heart valves, wires in sutures, bionic ears, subcutaneous infusion systems and (external) transdermal drug delivery patches1. The physician concerned with job placement of such persons requires information on the likelihood of an implant interacting with RFR so as to impair health. The following outlines the approach developed in Telecom Australia, beginning with the general principles and then presenting a specific example discussion of a specific example

  2. Bioactive Coatings for Orthopaedic Implants—Recent Trends in Development of Implant Coatings

    Directory of Open Access Journals (Sweden)

    Bill G. X. Zhang

    2014-07-01

    Full Text Available Joint replacement is a major orthopaedic procedure used to treat joint osteoarthritis. Aseptic loosening and infection are the two most significant causes of prosthetic implant failure. The ideal implant should be able to promote osteointegration, deter bacterial adhesion and minimize prosthetic infection. Recent developments in material science and cell biology have seen the development of new orthopaedic implant coatings to address these issues. Coatings consisting of bioceramics, extracellular matrix proteins, biological peptides or growth factors impart bioactivity and biocompatibility to the metallic surface of conventional orthopaedic prosthesis that promote bone ingrowth and differentiation of stem cells into osteoblasts leading to enhanced osteointegration of the implant. Furthermore, coatings such as silver, nitric oxide, antibiotics, antiseptics and antimicrobial peptides with anti-microbial properties have also been developed, which show promise in reducing bacterial adhesion and prosthetic infections. This review summarizes some of the recent developments in coatings for orthopaedic implants.

  3. Failure of total hip implants: metals and metal release in 52 cases

    DEFF Research Database (Denmark)

    Jakobsen, Stig Storgaard; Lidén, Carola; Søballe, Kjeld;

    2014-01-01

    Background . The pathogenesis of total joint replacement failure is multifactorial. One hypothesis suggests that corrosion and wear of alloys result in metal ion release, which may then cause sensitization and even implant failure, owing to the acquired immune reactivity. Objectives . To assess...... cobalt, nickel and chromium(VI) release from, and the metal composition of, failed metal-on-ethylene total hip replacements. Materials/methods . Implant components from 52 revision cases were evaluated with spot tests for free nickel, cobalt, and chromium (VI) ions. Implant composition was determined...... observed. Metal ions and particles corroded from metal-on-polyethylene may play a role in the complex aetiopathology of implant failure....

  4. International joint ventures

    DEFF Research Database (Denmark)

    Sørensen, Karsten Engsig

    2001-01-01

    The article analysis problems connected with corporate joint ventures. Among others the possible conflicts between the joint venture agreement and the statutes of the companies is examined, as well as certain problems connected to the fact that the joint venture partners have created commen control...... over their joint company....

  5. Osseointegration Implant Post Coupling With External Prosthetic Limb – Continuation of Previous Case Reports “Stage III”

    Directory of Open Access Journals (Sweden)

    Ronald Hillock, MD

    2014-07-01

    Acknowledgement: Design concept by Concept Design & Development, LLC (CDD,LLC; Development and Manufacturing by Signature Orthopaedics, LTD; Centennial Hills Hospital Medical Center, Las Vegas, NV; and Institutional Review Board (IRB by Joint Implant Surgery & Research Foundation.

  6. Dental Implant Systems

    Directory of Open Access Journals (Sweden)

    Yoshiki Oshida

    2010-04-01

    Full Text Available Among various dental materials and their successful applications, a dental implant is a good example of the integrated system of science and technology involved in multiple disciplines including surface chemistry and physics, biomechanics, from macro-scale to nano-scale manufacturing technologies and surface engineering. As many other dental materials and devices, there are crucial requirements taken upon on dental implants systems, since surface of dental implants is directly in contact with vital hard/soft tissue and is subjected to chemical as well as mechanical bio-environments. Such requirements should, at least, include biological compatibility, mechanical compatibility, and morphological compatibility to surrounding vital tissues. In this review, based on carefully selected about 500 published articles, these requirements plus MRI compatibility are firstly reviewed, followed by surface texturing methods in details. Normally dental implants are placed to lost tooth/teeth location(s in adult patients whose skeleton and bony growth have already completed. However, there are some controversial issues for placing dental implants in growing patients. This point has been, in most of dental articles, overlooked. This review, therefore, throws a deliberate sight on this point. Concluding this review, we are proposing a novel implant system that integrates materials science and up-dated surface technology to improve dental implant systems exhibiting bio- and mechano-functionalities.

  7. 21 CFR 888.3800 - Wrist joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3800 Section 888.3800 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Wrist joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. A wrist joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a wrist...

  8. 21 CFR 888.3170 - Elbow joint radial (hemi-elbow) polymer prosthesis.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Elbow joint radial (hemi-elbow) polymer prosthesis... (hemi-elbow) polymer prosthesis. (a) Identification. An elbow joint radial (hemi-elbow) polymer prosthesis is a device intended to be implanted made of medical grade silicone elastomer used to replace...

  9. 21 CFR 888.3310 - Hip joint metal/polymer constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3310 Section 888.3310 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/polymer constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal/polymer constrained cemented or uncemented prosthesis is a device intended to be implanted...

  10. 21 CFR 888.3480 - Knee joint femorotibial metallic constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3480 Section 888.3480 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Knee joint femorotibial metallic constrained cemented prosthesis. (a) Identification. A knee joint femorotibial metallic constrained cemented prosthesis is a device intended to be implanted to replace part of...

  11. 21 CFR 888.3180 - Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented prosthesis. 888.3180 Section 888.3180 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Elbow joint humeral (hemi-elbow) metallic uncemented prosthesis. (a) Identification. An elbow joint humeral (hemi-elbow) metallic uncemented prosthesis is a device intended to be implanted made of...

  12. 21 CFR 888.3110 - Ankle joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3110 Section 888.3110 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Ankle joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an...

  13. 21 CFR 888.3160 - Elbow joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3160 Section 888.3160 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Elbow joint metal/polymer semi-constrained cemented prosthesis. (a) Identification. An elbow joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace an...

  14. 21 CFR 888.3120 - Ankle joint metal/polymer non-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3120 Section 888.3120 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer non-constrained cemented prosthesis. (a) Identification. An ankle joint metal/polymer non-constrained cemented prosthesis is a device intended to be implanted to replace an ankle joint. The...

  15. 21 CFR 888.3340 - Hip joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3340 Section 888.3340 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Hip joint metal/composite semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/composite semi-constrained cemented prosthesis is a two-part device intended to be implanted to replace...

  16. 21 CFR 888.3100 - Ankle joint metal/composite semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented prosthesis. 888.3100 Section 888.3100 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF... Ankle joint metal/composite semi-constrained cemented prosthesis. (a) Identification. An ankle joint metal/composite semi-constrained cemented prosthesis is a device intended to be implanted to replace...

  17. 21 CFR 888.3350 - Hip joint metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3350 Section 888.3350 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer semi-constrained cemented prosthesis. (a) Identification. A hip joint metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a hip joint. The device...

  18. 21 CFR 888.3300 - Hip joint metal constrained cemented or uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3300 Section 888.3300 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal constrained cemented or uncemented prosthesis. (a) Identification. A hip joint metal constrained cemented or uncemented prosthesis is a device intended to be implanted to replace a hip joint. The...

  19. 中空多孔髋关节假体联合植入式输液港系统在治疗人工关节感染翻修中的意义%The significance of the “hollow porous hip prosthesis combined with implantable infusion port system” in the revision for infected joint arthroplasty

    Institute of Scientific and Technical Information of China (English)

    陈松; 符培亮; 丛锐军; 李晓华

    2013-01-01

      目的建立兔髋关节置换术后感染模型,探讨中空多孔髋关节假体联合植入式输液港系统在治疗髋关节置换术后感染二期翻修术中的意义.方法(1)日本大耳兔10只,处死后取右股骨,据此设计出1组为股骨头及柄中空且带孔的假体,1组为股骨头及柄实体的假体.(2)新西兰白兔100只(10只为备用),行右侧股骨假体置换术,术毕将含有1×108 CFU 耐甲氧西林金表皮葡萄球菌的菌液注入右侧髋关节内,术后4周时,兔人工股骨头置换后感染模型建立.(3)模型建立后清创,实验组45只兔植入中空多孔髋关节假体联合植入式输液港系统,分别于术后第1、3周初在输液港中注入万古霉素,其中22只于第4周末处死,另外23只于第5、7周初再次于输液港中注入万古霉素后,于第8周末处死.对照组45只兔植入用1∶20的 VCM-PMMA 固定的临时人工股骨头假体系统,其中22只于第4周末处死,另外23只于第8周末处死.观察两组感染控制率、关节周围软组织病理变化及假体位置.结果耐甲氧西林表皮葡萄球菌接种后4周所有动物的右侧髋关节均感染.实验组在植入中空假体后第4、8周末的感染数是4只和1只;对照组在植入 VCM-PMMA 临时假体后第4、8周末的感染数是7只和6只.中空多孔髋关节假体联合植入式输液港系统较 VCM-PMMA 临时假体系统在感染控制率方面具有优越性(χ2=4.44,P respectively at the end of the 4th and 8th weeks after the implantation of hollow prostheses, and the number of infected rabbits of the control group was 7 and 6 at the end of the 4th and 8th week respectively after the implantation of VCM-PMMA temporary prostheses. The “hollow porous hip prosthesis combined with implantable infusion port system” was superior in the infection rate when compared with the VCM-PMMA temporary prosthesis system (χ2=4.44, P<0.05). Conclusions The “hollow porous hip joint prosthesis

  20. 超声乳化联合囊袋内可调节人工晶状体植入术对白内障患者对比敏感度视觉影响研究%Impact of Joint Treatment of Phacoemulsification and Adjustable Intraocular Lens Implantation on Contrast Sensitivity in Patients with Cataract

    Institute of Scientific and Technical Information of China (English)

    Luay Radi Hasan Tayeh; 陈伟蓉; 林振德

    2013-01-01

    目的 探讨超声乳化联合囊袋内可调节人工晶状体植入术对白内障患者对比敏感度视觉恢复的影响,并分析相关机制.方法 回顾性分析2009年1月-2010年12月在我院住院治疗的78例(96只眼)白内障患者.其中38例46只眼行超声乳化联合囊袋内可调节人工晶状体植入术(为研究组),40例50只眼行白内障超声乳化联合囊袋内硬性人工晶状体植入术(为对照组).观察两组患者术后3个月矫正远、近视力,屈光度数,对比敏感度的变化以及并发症数量.结果 两组治疗后矫正近、远视力差异均无统计学意义(P>0.05);对比敏感度视觉检查结果显示,研究组有32例34只眼对比敏感度曲线在参考范围内;对照组29例32只眼对比敏感度曲线在正常范围内.研究组在高频段对比敏感度与对照组相比差异有统计学意义(P<0.05).对照组与研究组比较虹膜色素播散(13.15% vs.7.50%)、角膜内皮褶皱(18.42% vs.10.00%)、瞳孔变形(18.42% vs.5.00%)、角膜水肿(23.68% vs.7.50%)、前房纤维性渗出(21.05% vs.5.00%)发生率间差异均有统计学意义(P<0.05).结论 超声乳化联合囊袋内可调节人工晶状体植入术对白内障患者对比敏感度视觉具有一定调节作用,且并发症少.%Objective To evaluate impact of joint treatment of phacoemulsification and adjustable intraocular lens implantation on contrast sensitivity in patients with cataract, and analyze the related mechanism. Methods A total of 78 patients ( 96 eyes under treatment ) admitted into our hospital for the treatment of cataract between January 2009 and December 2010 were retrospectively analyzed. Among the 78 cases, 38 cases ( 46 eyes ) were treated with phacoemulsification and adjustable intraocular lens implantation ( study group ); the rest 40 cases ( 50 eyes ) were treated with phacoemulsification and hard intraocular lens implantation ( control group ) . Corrected distant and near vision, refraction

  1. Finite Element Investigation of Hybrid and Conventional Knee Implants

    Directory of Open Access Journals (Sweden)

    Habiba Bougherara

    2009-09-01

    Full Text Available Total Knee arthroplasty (TKA procedures relieve arthritic pain and restore jointfunction by replacing the contact surfaces of the knee joint. These proceduresare often performed following arthritic degeneration of the joint causing thepatient pain. Cobalt-chrome, stainless steel (316L grade and titanium alloys arewidely used in the majority of distal femoral implants in TKA procedures. The useof such stiff materials causes stress shielding (i.e. a lack of mechanical stressesbeing experienced by the bone surrounding the implant leading to gradual boneloss and implant failure. The aim of this paper is to develop a new hybrid kneeimplant which combines a polymer-composite (CF/PA-12 with an existingcommercial implant system (P.F.C.® Sigma™ made from stainless steel. Thishybrid implant is expected to alleviate stress shielding and bone loss bytransferring much more load to the femur compared to conventional metallicimplants. Results of the FEA simulations showed that the CF/PA-12 lined femoralcomponent generated almost 63% less in peak stress compared to the regularstainless steel component, indicating more load transfer to the bone andconsequently alleviating bone resorption.

  2. MEMS biomedical implants

    Institute of Scientific and Technical Information of China (English)

    Tai Yuchong

    2012-01-01

    The field of micro-electro-mechanical systems (MEMS) has advanced tremendously for the last 20 years. Most commercially noticeably, the field has successfully advanced from pressure sensors to micro physical sensors, such as accelerometers and gyros, for handheld electronics application. In parallel, MEMS has also advanced into micro total analysis system(TAS) and/or lab-on-a-chip applications. This article would discuss a relatively new but promising future direction towards MEMS biomedical implants. Specifically, Parylene C has been explored to be used as a good MEMS implant material and will be discussed in detail. Demonstrated implant devices, such as retinal and spinal cord implants, are presented in this article.

  3. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne;

    2011-01-01

    Studies of complications following reconstructive surgery with implants among women with breast cancer are needed. As the, to our knowledge, first prospective long-term study we evaluated the occurrence of complications following delayed breast reconstruction separately for one- and two......-stage procedures. From the Danish Registry for Plastic Surgery of the Breast, which has prospectively registered data for women undergoing breast implantations since 1999, we identified 559 women without a history of radiation therapy undergoing 592 delayed breast reconstructions following breast cancer during...... of reoperation was significantly higher following the one-stage procedure. For both procedures, the majority of reoperations were due to asymmetry or displacement of the implant. In conclusion, non-radiated one- and two-stage delayed breast implant reconstructions are associated with substantial risks...

  4. Ion Implantation of Polymers

    DEFF Research Database (Denmark)

    Popok, Vladimir

    2012-01-01

    The current paper presents a state-of-the-art review in the field of ion implantation of polymers. Numerous published studies of polymers modified by ion beams are analysed. General aspects of ion stopping, latent track formation and changes of structure and composition of organic materials...... are discussed. Related to that, the effects of radiothermolysis, degassing and carbonisation are considered. Specificity of depth distributions of implanted into polymers impurities is analysed and the case of high-fluence implantation is emphasised. Within rather broad topic of ion bombardment, the focus...... is put on the low-energy implantation of metal ions causing the nucleation and growth of nanoparticles in the shallow polymer layers. Electrical, optical and magnetic properties of metal/polymer composites are under the discussion and the approaches towards practical applications are overviewed....

  5. Cochlear Implant in Adults

    Directory of Open Access Journals (Sweden)

    Jaleh Samadi

    2003-09-01

    Full Text Available Cochlear implant is the result of a great combination and collaboration of engineering and medicine. It is mainly because it has the most conflict with the human nervous system among all prosthesis. Cochlear implant helps a child with profound hearing loss to understand and articulate speech and let an adult person with hearing loss communicate with people by phone. Although these wonderful results could not be seen in all patients, will let us know about the great scientific findings.

  6. BREAST IMPLANT SURFACE DEVELOPMENT

    OpenAIRE

    Valencia Lazenco, Anai Alicia

    2015-01-01

    Bilateral breast augmentation is one of the most common cosmetic surgical procedures carried out on women in the western world. Breast augmentation involves increasing the volume of a woman‘s breasts through surgery by placing a silicone implant in the subglandular or subpectoral cavity. Although a capsule forms inevitably around breast implants as a natural part of healing, it can cause significant morbidity if the capsule becomes firm and contracted, a condition known as breast capsular con...

  7. Simple Implant Augmentation Rhinoplasty.

    Science.gov (United States)

    Nguyen, Anh H; Bartlett, Erica L; Kania, Katarzyna; Bae, Sang Mo

    2015-11-01

    Augmentation rhinoplasty among Asian patients is often performed to improve the height of the nasal dorsum. As the use of autogenous tissues poses certain limitations, alloplastic materials are a viable alternative with a long history of use in Asia. The superiority of one implant prosthesis over another for augmentation rhinoplasty is a matter of debate, with each material representing varying strengths and weaknesses, indications for use, and precautions to consider in nasal implant placement. An implant prosthesis should be used on a case-by-case basis. Augmentation rhinoplasty requires the consideration of specific anatomical preoperative factors, including the external nose, nasal length, nasofrontal angle, humps, and facial proportions. It is equally important to consider several operative guidelines to appropriately shape implants to minimize the occurrence of adverse effects and postoperative complications. The most common postoperative complications include infection, nasal height change, movement of implant prosthesis, and silicone implant protrusion. In addition, the surgeon should consider the current standards of Asian beauty aesthetics to better understand the patient's desired outcome. PMID:26648804

  8. Contraceptive implants: current perspectives

    Directory of Open Access Journals (Sweden)

    Rowlands S

    2014-09-01

    Full Text Available Sam Rowlands,1,2 Stephen Searle3 1Centre of Postgraduate Medical Research and Education, School of Health and Social Care, Bournemouth University, Bournemouth, United Kingdom; 2Dorset HealthCare, Bournemouth, United Kingdom; 3Sexual Health Services, Chesterfield, United KingdomAbstract: Progestin-only contraceptive implants are a highly cost-effective form of long-acting reversible contraception. They are the most effective reversible contraceptives and are of a similar effectiveness to sterilization. Pregnancies are rare in women using this method of contraception, and those that do occur must be fully investigated, with an ultrasound scan of the arm and serum etonogestrel level if the implant cannot be located. There are very few contraindications to use of implants, and they have an excellent safety profile. Both acceptability and continuation with the method are high. Noncontraceptive benefits include improvements in dysmenorrhea, ovulatory pain, and endometriosis. Problematic bleeding is a relatively common adverse effect that must be covered in preinsertion information-giving and supported adequately if it occurs. Recognized training for both insertion and removal should be undertaken. Care needs to be taken at both insertion and removal to avoid neurovascular injury. Implants should always be palpable; if they are not, noninsertion should be assumed until disproven. Etonogestrel implants are now radiopaque, which aids localization. Anticipated difficult removals should be performed by specially trained experts. Keywords: contraceptive, subdermal implant, etonogestrel, levonorgestrel, progestin-only, long-acting reversible contraception

  9. Biomaterials in cochlear implants

    Directory of Open Access Journals (Sweden)

    Lenarz, Thomas

    2009-01-01

    Full Text Available The cochlear implant (CI represents, for almost 25 years now, the gold standard in the treatment of children born deaf and for postlingually deafened adults. These devices thus constitute the greatest success story in the field of ‘neurobionic’ prostheses. Their (now routine fitting in adults, and especially in young children and even babies, places exacting demands on these implants, particularly with regard to the biocompatibility of a CI’s surface components. Furthermore, certain parts of the implant face considerable mechanical challenges, such as the need for the electrode array to be flexible and resistant to breakage, and for the implant casing to be able to withstand external forces. As these implants are in the immediate vicinity of the middle-ear mucosa and of the junction to the perilymph of the cochlea, the risk exists – at least in principle – that bacteria may spread along the electrode array into the cochlea. The wide-ranging requirements made of the CI in terms of biocompatibility and the electrode mechanism mean that there is still further scope – despite the fact that CIs are already technically highly sophisticated – for ongoing improvements to the properties of these implants and their constituent materials, thus enhancing the effectiveness of these devices. This paper will therefore discuss fundamental material aspects of CIs as well as the potential for their future development.

  10. The polymethylmethacrylate antibiotic spacer for treatment of joint infection

    Directory of Open Access Journals (Sweden)

    Manuel Bondi

    2014-09-01

    Full Text Available Joint prostheses chronic infection requires surgical removal of the implant, in order to eradicate the infection process. The Polymethylmethacrylate (PMMA bone cement is a good carrier for the sustained antibiotic release at the site of infection. PMMA cements pre-loaded with antibiotics are utilized for prophylaxis, primary surgical procedure and the treatment of prosthetic joint infections. The mechanical and functional characteristics of the spacers allow a good joint range of motion, weight-bearing in selected cases and a sustained release of antibiotic at the site of infection. These drug delivery systems offer the advantage of local release of high antibiotic concentrations, which considerably exceed those obtained after systemic administration. Nowadays treatment with a preformed antibiotic loaded spacer can be considered a good option for joint prostheses infection maintaining joint function at the intermediate stage in two-stage treatment.

  11. Investigations of Titanium Implants Covered with Hydroxyapatite Layer

    Directory of Open Access Journals (Sweden)

    Świeczko – Żurek B.

    2016-06-01

    Full Text Available To reduce unfavorable phenomena occurring after introducing an implant into human body various modifications of the surface are suggested. Such modifications may have significant impact on biocompatibility of metallic materials. The titanium and it's alloys are commonly used for joint and dental implants due to their high endurance, low plasticity modulus, good corrosion resistance as well as biocompatibility. Special attention should be given to titanium alloys containing zirconium, tantalum and niobium elements. These new generation alloys are used by worldwide engineering specialists. The experiments were performed with hydroxyapatite layer on titanium specimens with the use of electrophoresis method (different voltage and time.

  12. Knee joint replacement - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100088.htm Knee joint replacement - series To use the sharing features ... 4 out of 4 Normal anatomy Overview The knee is a complex joint. It contains the distal ...

  13. Culture - joint fluid

    Science.gov (United States)

    Joint fluid culture ... fungi, or viruses grow. This is called a culture. If these germs are detected, other tests may ... is no special preparation needed for the lab culture. How to prepare for the removal of joint ...

  14. Iatrogenic Tumor Implantation

    Institute of Scientific and Technical Information of China (English)

    Ying Ma; Ping Bai

    2008-01-01

    Iatrogenic tumor implantation is a condition that results from various medical procedures used during diagnosis or treatment of a malignancy. It involves desquamation and dissemination of tumor cells that develop into a local recurrence or distant metastasis from the tumor under treatment. The main clinical feature of the condition is nodules at the operation's porous channel or incision, which is easily diagnosed in accordance with the case history. Final diagnosis can be made based on pathological examination. Tumor implantation may occur in various puncturing porous channels, including a laparoscopic port, abdominal wall incision, and perineal incision, etc. Besides a malignant tumor,implantation potential exists with diseases, such as a borderline tumor and endometriosis etc. Once a tumor implantation is diagnosed, or suspected, surgical resection is usually conducted.During the diagnosis and treatment of diseases, avoiding and reducing iatrogenic implantation and dissemination has been regarded as an important principle for surgical treatment of tumors. In a clinical practice setting, if possible, excisional biopsy should be employed, if a biopsy is needed. Repeated puncturing should be avoided during a paracentesis. In a laparoscopic procedure, the tissue is first put into a sample bag and then is taken out from the point of incision. After a laparoscopic procedure, the peritoneum, abdominal muscular fasciae, and skin should be carefully closed, and/or the punctured porous channel be excised. In addition, the sample/tissue should be rinsed with distilled water before surgical closure of the abdominal cavity,allowing the exfoliated tumor cells to swell and rupture in the hypo-osmolar solution. Then surgical closure can be conducted following a change of gloves and equipment. The extent of hysteromyomectomy should as far as possible be away from the uterine cavity. The purpose of this study is to make clinicians aware of the possibility of tumor implantation

  15. Propionibacterium acnes: An Underestimated Pathogen in Implant-Associated Infections

    Directory of Open Access Journals (Sweden)

    María Eugenia Portillo

    2013-01-01

    Full Text Available The role of Propionibacterium acnes in acne and in a wide range of inflammatory diseases is well established. However, P. acnes is also responsible for infections involving implants. Prolonged aerobic and anaerobic agar cultures for 14 days and broth cultures increase the detection rate. In this paper, we review the pathogenic role of P. acnes in implant-associated infections such as prosthetic joints, cardiac devices, breast implants, intraocular lenses, neurosurgical devices, and spine implants. The management of severe infections caused by P. acnes involves a combination of antimicrobial and surgical treatment (often removal of the device. Intravenous penicillin G and ceftriaxone are the first choice for serious infections, with vancomycin and daptomycin as alternatives, and amoxicillin, rifampicin, clindamycin, tetracycline, and levofloxacin for oral treatment. Sonication of explanted prosthetic material improves the diagnosis of implant-associated infections. Molecular methods may further increase the sensitivity of P. acnes detection. Coating of implants with antimicrobial substances could avoid or limit colonization of the surface and thereby reduce the risk of biofilm formation during severe infections. Our understanding of the role of P. acnes in human diseases will likely continue to increase as new associations and pathogenic mechanisms are discovered.

  16. The pathobiology and pathology of aseptic implant failure

    Science.gov (United States)

    2016-01-01

    Pathological assessment of periprosthetic tissues is important, not only for diagnosis, but also for understanding the pathobiology of implant failure. The host response to wear particle deposition in periprosthetic tissues is characterised by cell and tissue injury, and a reparative and inflammatory response in which there is an innate and adaptive immune response to the material components of implant wear. Physical and chemical characteristics of implant wear influence the nature of the response in periprosthetic tissues and account for the development of particular complications that lead to implant failure, such as osteolysis which leads to aseptic loosening, and soft-tissue necrosis/inflammation, which can result in pseudotumour formation. The innate response involves phagocytosis of implant-derived wear particles by macrophages; this is determined by pattern recognition receptors and results in expression of cytokines, chemokines and growth factors promoting inflammation and osteoclastogenesis; phagocytosed particles can also be cytotoxic and cause cell and tissue necrosis. The adaptive immune response to wear debris is characterised by the presence of lymphoid cells and most likely occurs as a result of a cell-mediated hypersensitivity reaction to cell and tissue components altered by interaction with the material components of particulate wear, particularly metal ions released from cobalt-chrome wear particles. Cite this article: Professor N. A. Athanasou. The pathobiology and pathology of aseptic implant failure. Bone Joint Res 2016;5:162–168. DOI: 10.1302/2046-3758.55.BJR-2016-0086. PMID:27146314

  17. Imaging for cochlear implants.

    Science.gov (United States)

    Phelps, P D; Annis, J A; Robinson, P J

    1990-07-01

    Insertion of a sound amplification device into the round window niche (extracochlear implant) or into the coils of the cochlea (intracochlear implant) can give significant benefits to some carefully selected, severely deaf patients. Imaging has an essential role in selective and pre-operative assessment. Severe otosclerosis and post-meningitic labyrinthitis ossificans are common causes of deafness in these patients and can be demonstrated by computed tomography (CT). The most suitable side for operation can be assessed. We describe our experiences with 165 patients, 69 of whom were found suitable for implants. Thin (1 mm) section CT in axial and coronal planes is the best imaging investigation of the petrous temporal bones but the place of magnetic resonance scanning to confirm that the inner ear is fluid-filled and polytomography to show a multichannel implant in the cochlea is discussed. No implants were used for congenital deformities, but some observations are made of this type of structural deformity of the inner ear. PMID:2390686

  18. Psychological intervention following implantation of an implantable defibrillator

    DEFF Research Database (Denmark)

    Pedersen, Susanne S.; van den Broek, Krista C; Sears, Samuel F

    2007-01-01

    The medical benefits of the implantable cardioverter defibrillator (ICD) are unequivocal, but a subgroup of patients experiences emotional difficulties following implantation. For this subgroup, some form of psychological intervention may be warranted. This review provides an overview of current...

  19. Dental Implant Complications.

    Science.gov (United States)

    Liaw, Kevin; Delfini, Ronald H; Abrahams, James J

    2015-10-01

    Dental implants have increased in the last few decades thus increasing the number of complications. Since many of these complications are easily diagnosed on postsurgical images, it is important for radiologists to be familiar with them and to be able to recognize and diagnose them. Radiologists should also have a basic understanding of their treatment. In a pictorial fashion, this article will present the basic complications of dental implants which we have divided into three general categories: biomechanical overload, infection or inflammation, and other causes. Examples of implant fracture, loosening, infection, inflammation from subgingival cement, failure of bone and soft tissue preservation, injury to surround structures, and other complications will be discussed as well as their common imaging appearances and treatment. Lastly, we will review pertinent dental anatomy and important structures that are vital for radiologists to evaluate in postoperative oral cavity imaging.

  20. [The spectrum of histomorphological findings related to joint endoprosthetics].

    Science.gov (United States)

    Morawietz, L; Krenn, V

    2014-11-01

    Approximately 230,000 total hip and 170,000 knee joint endoprostheses are implanted in Germany annually of which approximately 10% (i.e. 40,000 interventions per year) are cases of revision surgery. These interventions involve removal of a previously implanted prosthesis which has resulted in complaints and replacement with a new prosthesis. There are manifold reasons for revision surgery, the most common indication being so-called endoprosthesis loosening, which is subdivided into septic and aseptic loosening. Histomorphological studies revealed that periprosthetic tissue from endoprosthesis loosening can be classified into four types (I) wear-particle induced type, (II) infectious type, (III) combined type and (IV) fibrous type. Types I and IV represent aseptic loosening and types II and III septic loosening. Recently, the topic of implant allergy has emerged. The detection of cellular, mostly perivascular lymphocytic infiltrates is discussed as being a sign of an allergic tissue reaction. It has most frequently been observed in type I periprosthetic membranes with a dense load of metal wear, which occurs with metal-on-metal bearings. Apart from endoprosthesis loosening, arthrofibrosis is another complication of joint endoprosthetics and can cause pain and impaired function. Histopathologically, arthrofibrosis can be evaluated by a three-tiered grading system. Furthermore, bone pathologies, such as ossification, osteopenia or osteomyelitis can occur as complications of joint endoprosthetics. This review gives an overview of the whole spectrum of pathological findings in joint endoprosthetics and offers a comprehensive and standardized classification system for routine histopathological diagnostics. PMID:25230805

  1. Modeling Implantable Passive Mechanisms for Modifying the Transmission of Forces and Movements Between Muscle and Tendons.

    Science.gov (United States)

    Homayouni, Taymaz; Underwood, Kelsey N; Beyer, Kamin C; Martin, Elon R; Allan, Christopher H; Balasubramanian, Ravi

    2015-09-01

    This paper explores the development of biomechanical models for evaluating a new class of passive mechanical implants for orthopedic surgery. The proposed implants take the form of passive engineered mechanisms, and will be used to improve the functional attachment of muscles to tendons and bone by modifying the transmission of forces and movement inside the body. Specifically, we present how two types of implantable mechanisms may be modeled in the open-source biomechanical software OpenSim. The first implant, which is proposed for hand tendon-transfer surgery, differentially distributes the forces and movement from one muscle across multiple tendons. The second implant, which is proposed for knee-replacement surgery, scales up the forces applied to the knee joint by the quadriceps muscle. This paper's key innovation is that such mechanisms have never been considered before in biomechanical simulation modeling and in surgery. When compared with joint function enabled by the current surgical practice of using sutures to make the attachment, biomechanical simulations show that the surgery with 1) the differential mechanism (tendon network) implant improves the fingers' ability to passively adapt to an object's shape significantly during grasping tasks (2.74× as measured by the extent of finger flexion) for the same muscle force, and 2) the force-scaling implant increases knee-joint torque by 84% for the same muscle force. The critical significance of this study is to provide a methodology for the design and inclusion of the implants into biomechanical models and validating the improvement in joint function they enable when compared with current surgical practice. PMID:25850081

  2. The ethical allocation of scarce resources in surgery: implants and cost

    OpenAIRE

    Gross, Michael

    1997-01-01

    This paper is a discussion of the factors involved in instituting a bulk purchasing program for surgical supplies. An improved understanding of the surgical procedure of joint arthroplasty must relate to the variability in surgical methods that achieve patient outcomes. An understanding of the outcomes in relation to the expected duration of the success of an implant and the high costs associated with a revision earlier than expected must be factored into the budget and costs of implants. The...

  3. Caborane beam from ITEP Bernas ion source for semiconductor implanters

    Energy Technology Data Exchange (ETDEWEB)

    Seleznev, D.; Hershcovitch, A.; Kropachev, G.; Kozlov, A.; Kuibeda, R.; Koshelev, V.; Kulevoy, T.; Jonson, B.; Poole, J.; Alexeyenko, O.; Gurkova, E.; Oks, E.; Gushenets, V.; Polozov, S.; Masunov, E.

    2010-02-01

    A joint research and development of steady state intense boron ion sources for hundreds of electron-volt ion implanters has been in progress for the past 5 years. The difficulties of extraction and transportation of low energy boron beams can be solved by implanting clusters of boron atoms. In Institute for Theoretical and Experimental Physics (ITEP) the Bernas ion source successfully generated the beam of decaborane ions. The carborane (C{sub 2}B{sub 10}H{sub 12}) ion beam is more attractive material due to its better thermal stability. The results of carborane ion beam generation are presented. The result of the beam implantation into the silicon wafer is presented as well.

  4. [Carbon fiber-reinforced plastics as implant materials].

    Science.gov (United States)

    Bader, R; Steinhauser, E; Rechl, H; Siebels, W; Mittelmeier, W; Gradinger, R

    2003-01-01

    Carbon fiber-reinforced plastics have been used clinically as an implant material for different applications for over 20 years.A review of technical basics of the composite materials (carbon fibers and matrix systems), fields of application,advantages (e.g., postoperative visualization without distortion in computed and magnetic resonance tomography), and disadvantages with use as an implant material is given. The question of the biocompatibility of carbon fiber-reinforced plastics is discussed on the basis of experimental and clinical studies. Selected implant systems made of carbon composite materials for treatments in orthopedic surgery such as joint replacement, tumor surgery, and spinal operations are presented and assessed. Present applications for carbon fiber reinforced plastics are seen in the field of spinal surgery, both as cages for interbody fusion and vertebral body replacement.

  5. Therapeutic intervention for wear debris-induced aseptic implant loosening

    Directory of Open Access Journals (Sweden)

    Ke Ren

    2013-04-01

    Full Text Available Wear debris-induced aseptic loosening is an inflammatory bone disorder, which compromises the long-term success of total joint replacement. Despite the extensive research and great progress in treating inflammation-induced osteolysis for inflammatory arthritis, no drug has been proven for treatment/prevention of aseptic implant loosening. Also, there is very limited research on developing effective drug delivery systems for this pathological condition. In this review, we will discuss different therapeutic interventions and various delivery systems that have been developed for aseptic implant loosening. To provide the prospective for the future research in this area, the biology of wear particles-induced osteolysis, animal models developed for aseptic implant loosening and the potential challenges the field is facing are also presented in the discussion.

  6. Evaluation of breast silicone implants.

    Science.gov (United States)

    Brenner, R James

    2013-08-01

    While clinical evaluation of breast implants and their complications can identify capsule contracture and rupture of saline implants, the identification of silicone implant failure is best accomplished by silicone specific protocols for MRI with orthogonal acquisition. Such imaging can also help resolve other clinical problems. Following a brief overview of the history and development of commercial use of silicone implants and alternatives, this article outlines the approach toward optimal imaging and expected results.

  7. The ruptured PIP breast implant

    International Nuclear Information System (INIS)

    Public concern erupted about the safety of Poly Implant Prothèse (PIP) breast implants when it was revealed in 2011 that they contained an inferior, unlicensed industrial-grade silicone associated with a high rate of rupture. There followed national guidance for UK clinicians, which led to a considerable increase in referrals of asymptomatic women for breast implant assessment. In this review we discuss possible approaches to screening the PIP cohort and the salient characteristics of a ruptured implant

  8. Dental implants in growing children

    OpenAIRE

    S.K. Mishra; Chowdhary, N.; Chowdhary, R.

    2013-01-01

    The replacement of teeth by implants is usually restricted to patients with completed craniofacial growth. The aim of this literature review is to discuss the use of dental implants in normal growing patients and in patients with ectodermal dysplasia and the influence of maxillary and mandibular skeletal and dental growth on the stability of those implants. It is recommended that while deciding the optimal individual time point of implant insertion, the status of skeletal growth, the degree o...

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

    Science.gov (United States)

    Babiker, Hassan

    2013-07-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include the risk of bacterial contamination and disease transmission as well as non-union and poor bone quality. Other bone graft and substitutes have been considered as alternative in order to improve implant fixation. Hydroxyapatite and collagen type I composite (HA/Collagen) have the potential in mimicking skeletal bones. The osteoconductive properties of the composite might be improved by adding bone marrow aspirate (BMA), which can be harvested during surgery. Other alternatives to bone graft are demineralised bone matrix (DBM) and human cancellous bone (CB). DBM is prepared by acid extraction of human bone and includes bone collagen, morphogenetic proteins and growth factors. The combination of DBM with CB and with allograft might improve the healing potential of these grafts around non-cemented orthopaedic implants and thereby the implant fixation. Study I investigates the effect of HA/Collagen composite alone and in combination with BMA on the early fixation of porous coated titanium implants. In addition, the study compares also the effect of autograft with the gold standard allograft. By using a sheep model, the implants were inserted in the trabecular bone of femoral condyles. The test biomaterials were placed in a well defined peri-implant gap. After the observation period, the bone-implant specimens were harvested and evaluated mechanically by a destructive push

  10. Implantable Impedance Plethysmography

    Directory of Open Access Journals (Sweden)

    Michael Theodor

    2014-08-01

    Full Text Available We demonstrate by theory, as well as by ex vivo and in vivo measurements that impedance plethysmography, applied extravascularly directly on large arteries, is a viable method for monitoring various cardiovascular parameters, such as blood pressure, with high accuracy. The sensor is designed as an implant to monitor cardiac events and arteriosclerotic progression over the long term.

  11. Remote actuated valve implant

    Science.gov (United States)

    McKnight, Timothy E; Johnson, Anthony; Moise, Jr., Kenneth J; Ericson, Milton Nance; Baba, Justin S; Wilgen, John B; Evans, III, Boyd McCutchen

    2014-02-25

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  12. Corrosion of bio implants

    Indian Academy of Sciences (India)

    U Kamachi Mudali; T M Sridhar; Baldev Raj

    2003-06-01

    Chemical stability, mechanical behaviour and biocompatibility in body fluids and tissues are the basic requirements for successful application of implant materials in bone fractures and replacements. Corrosion is one of the major processes affecting the life and service of orthopaedic devices made of metals and alloys used as implants in the body. Among the metals and alloys known, stainless steels (SS), Co–Cr alloys and titanium and its alloys are the most widely used for the making of biodevices for extended life in human body. Incidences of failure of stainless steel implant devices reveal the occurrence of significant localised corroding viz., pitting and crevice corrosion. Titanium forms a stable TiO2 film which can release titanium particles under wear into the body environment. To reduce corrosion and achieve better biocompatibility, bulk alloying of stainless steels with titanium and nitrogen, surface alloying by ion implantation of stainless steels and titanium and its alloys, and surface modification of stainless steel with bioceramic coatings are considered potential methods for improving the performance of orthopaedic devices. This review discusses these issues in depth and examines emerging directions.

  13. Remote actuated valve implant

    Energy Technology Data Exchange (ETDEWEB)

    McKnight, Timothy E.; Johnson, Anthony; Moise, Kenneth J.; Ericson, Milton Nance; Baba, Justin S.; Wilgen, John B.; Evans, Boyd Mccutchen

    2016-05-10

    Valve implant systems positionable within a flow passage, the systems having an inlet, an outlet, and a remotely activatable valve between the inlet and outlet, with the valves being operable to provide intermittent occlusion of the flow path. A remote field is applied to provide thermal or magnetic activation of the valves.

  14. Ion implantation in polymers

    Science.gov (United States)

    Wintersgill, M. C.

    1984-02-01

    An introductory overview will be given of the effects of ion implantation on polymers, and certain areas will be examined in more detail. Radiation effects in general and ion implantation in particular, in the field of polymers, present a number of contrasts with those in ionic crystals, the most obvious difference being that the chemical effects of both the implanted species and the energy transfer to the host may profoundly change the nature of the target material. Common effects include crosslinking and scission of polymer chains, gas evolution, double bond formation and the formation of additional free radicals. Research has spanned the chemical processes involved, including polymerization reactions achievable only with the use of radiation, to applied research dealing both with the effects of radiation on polymers already in commercial use and the tailoring of new materials to specific applications. Polymers are commonly divided into two groups, in describing their behavior under irradiation. Group I includes materials which form crosslinks between molecules, whereas Group II materials tend to degrade. In basic research, interest has centered on Group I materials and of these polyethylene has been studied most intensively. Applied materials research has investigated a variety of polymers, particularly those used in cable insulation, and those utilized in ion beam lithography of etch masks. Currently there is also great interest in enhancing the conducting properties of polymers, and these uses would tend to involve the doping capabilities of ion implantation, rather than the energy deposition.

  15. 21 CFR 888.3535 - Knee joint femorotibial (uni-compartmental) metal/polymer porous-coated uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    .../polymer porous-coated uncemented prosthesis. 888.3535 Section 888.3535 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A knee joint femorotibial (uni-compartmental) metal/polymer porous-coated uncemented prosthesis is a device intended to be implanted to replace part of a knee joint. The device...

  16. 21 CFR 888.3560 - Knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    .../polymer semi-constrained cemented prosthesis. 888.3560 Section 888.3560 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A knee joint patellofemorotibial polymer/metal/polymer semi-constrained cemented prosthesis is a device intended to be implanted to replace a knee joint. The device...

  17. 21 CFR 888.3330 - Hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... uncemented acetabular component, prosthesis. 888.3330 Section 888.3330 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with an uncemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  18. 21 CFR 888.3320 - Hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented acetabular component, prosthesis. 888.3320 Section 888.3320 Food and Drugs FOOD AND DRUG..., prosthesis. (a) Identification. A hip joint metal/metal semi-constrained, with a cemented acetabular component, prosthesis is a two-part device intended to be implanted to replace a hip joint. The...

  19. 21 CFR 888.3353 - Hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... cemented or nonporous uncemented prosthesis. 888.3353 Section 888.3353 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/ceramic/polymer semi-constrained cemented or nonporous uncemented prosthesis is a device intended to be implanted to replace a hip joint. This device...

  20. Focal anatomic resurfacing implantation for bilateral humeral and femoral heads’ avascular necrosis in a patient with Hodgkin’s lymphoma and literature review

    Directory of Open Access Journals (Sweden)

    Onur Bilge

    2015-01-01

    Conclusion: This study is the first report to present the three-years’ clinical result of a single, relevant case, who was treated with sequential focal anatomic resurfacing implantations (HemiCAP® in four aforementioned joints.

  1. Failure mechanisms of polyester fiber anterior cruciate ligament implants: A human retrieval and laboratory study.

    Science.gov (United States)

    Amis, A A; Kempson, S A

    1999-01-01

    It has been hypothesized that ACL implant failure is often caused by bone impingement in knee extension following malplacement of the tibial tunnel. This study examined polyethylene terephtalate fiber ACL implants retrieved from a clinical study, and, to confirm the hypothesis, also set up a laboratory study intended to duplicate the failure mechanism. SEM and TEM examination of 25 ruptured implants gave details of fiber failure morphology, with shearing into longitudinal fibrils, followed by rupture, when the fibrils burst apart. Cadaver joints were run in a knee simulator, with deliberately impinging ACL implants. SEM examination of implants abraded in the knee in vitro showed identical fiber damage patterns, thus confirming the impingement hypothesis. PMID:10421698

  2. Surgeons' knowledge about the costs of orthopaedic implants.

    Science.gov (United States)

    Rohman, Lebur; Hadi, Saifullah; Whitwell, George

    2014-08-01

    PURPOSE. To investigate consultant surgeons' knowledge about the costs of implants for various joint surgeries. METHODS. Questionnaires were distributed to consultant orthopaedic surgeons at 2 hospitals. Respondents were asked to estimate the implant costs of any brand for low-demand and high-demand total hip replacement (THR), total knee replacement (TKR), uni-compartmental knee replacement, arthroscopy shaver blade, total anterior cruciate ligament (ACL) fixation, and meniscal repair. The actual cost of each implant was obtained from the manufacturer. RESULTS. 16 consultant surgeons completed the questionnaires. The respective mean estimated and actual costs for a low-demand THR implant were £1714 (range, £600-3000) and £1448 (range, £985- 2335), with an overestimation of 18.4%. The respective costs for a high-demand THR implant were £2172 (range, £600-6000) and £1737 (range, £1192-2335), with an overestimation of 25%. The respective costs for a TKR implant were £1550 (range, £600-6000) and £1316 (range, £995-1535), with an overestimation of 17.8%. The respective costs for a uni-compartmental knee replacement implant were £1040 (range, £600-2000) and £1296 (range, £698-1470), with an underestimation of 19.7%. The respective costs for an arthroscopy shaver blade were £110 (range, £75-150) and £94 (range, £80-100), with an overestimation of 16.6%. The respective costs for a total ACL fixation implant were £246 (range, £80-500) and £306 (range, £272-335), with an underestimation of 19.4%. The respective costs for a meniscal repair implant were £153 (range, £50-250) and £242 (range, £170-260), with an underestimation of 37%. CONCLUSION. The knowledge among consultant orthopaedic surgeons about implant costs was poor. To reduce implant costs, cooperation between surgeons and hospital managers and measures to increase surgeons' awareness about cost-reduction programmes are needed. PMID:25163960

  3. Jointly Poisson processes

    CERN Document Server

    Johnson, D H

    2009-01-01

    What constitutes jointly Poisson processes remains an unresolved issue. This report reviews the current state of the theory and indicates how the accepted but unproven model equals that resulting from the small time-interval limit of jointly Bernoulli processes. One intriguing consequence of these models is that jointly Poisson processes can only be positively correlated as measured by the correlation coefficient defined by cumulants of the probability generating functional.

  4. Gold Bead Implantation in Acupoints for Coxofemoral Arthrosis in Dogs: Method Description and Adverse Effects

    Directory of Open Access Journals (Sweden)

    Lars Moe

    2012-09-01

    Full Text Available Gold bead implantation has been used for years as an alternative method to improve function in chronic joint disease both in humans and dogs. The aims of the present study were to describe the technique of implanting 24-karat gold beads around the hip joints of dogs with chronic hip dysplasia, and to record any side effects or complications of such treatment. A prospective placebo-controlled double-blinded clinical trial was performed. Eighty dogs were randomly allocated to treatment or placebo, with 38 in the gold implantation group and 42 in the placebo group, and followed intensely for six months. The implantation technique was simple to perform, using fluoroscopy and with the dogs under inhalation anesthesia for about 30 minutes. Adverse effects, measured as pain or discomfort, were seen for a period of up to four weeks in 15 of the dogs in the gold implantation group, compared to six dogs in the placebo group. During implantation, a technical difficulty occurred as 82% of the dogs showed leakage of blood and/or synovia from the needles. The dogs in the gold implantation group were radiographed 18 months later. Of the 30 dogs that were radiographed at both inclusion and 24 months, 80% (24 dogs showed a deterioration of the coxofemoral arthrosis, the other six had stable disease evaluated by radiography. Migration of gold beads was only observed in one dog.

  5. Surface modification of ultra-high molecular weight polyethylene for joint prosthesis and sports applications

    Institute of Scientific and Technical Information of China (English)

    H.Dong

    2004-01-01

    The recent progresses in the surfaee modification of ultra high molecular weight polyethylene (UHMWPE) using such advanced surface modification technologies as conventional ion implantation (CⅡ), new plasma immersion ion implantation (PⅢ) and novel active screen plasma (ASP), were all reported. Significantly improved wear resistance was achieved, which has great potential for extending the life-span of joint replacement prostheses and enhancing the performance of such sports equipment as skis and snowboards.

  6. Mechanics of Sheeting Joints

    Science.gov (United States)

    Martel, S. J.

    2015-12-01

    Physical breakdown of rock across a broad scale spectrum involves fracturing. In many areas large fractures develop near the topographic surface, with sheeting joints being among the most impressive. Sheeting joints share many geometric, textural, and kinematic features with other joints (opening-mode fractures) but differ in that they are (a) discernibly curved, (b) open near the topographic surface, and (c) form subparallel to the topographic surface. Where sheeting joints are geologically young, the surface-parallel compressive stresses are typically several MPa or greater. Sheeting joints are best developed beneath domes, ridges, and saddles; they also are reported, albeit rarely, beneath valleys or bowls. A mechanism that accounts for all these associations has been sought for more than a century: neither erosion of overburden nor high lateral compressive stresses alone suffices. Sheeting joints are not accounted for by Mohr-Coulomb shear failure criteria. Principles of linear elastic fracture mechanics, together with the mechanical effect of a curved topographic surface, do provide a basis for understanding sheeting joint growth and the pattern sheeting joints form. Compressive stresses parallel to a singly or doubly convex topographic surface induce a tensile stress perpendicular to the surface at shallow depths; in some cases this alone could overcome the weight of overburden to open sheeting joints. If regional horizontal compressive stresses, augmented by thermal stresses, are an order of magnitude or so greater than a characteristic vertical stress that scales with topographic amplitude, then topographic stress perturbations can cause sheeting joints to open near the top of a ridge. This topographic effect can be augmented by pressure within sheeting joints arising from water, ice, or salt. Water pressure could be particularly important in helping drive sheeting joints downslope beneath valleys. Once sheeting joints have formed, the rock sheets between

  7. Peri-implant hastalıklar

    OpenAIRE

    Dilsiz, Alparslan; Zihni, Meltem; Yavuz, M Selim

    2011-01-01

    The treatment of partially or totally edentulous subjects with oral implants is a common procedure. Biological complications are occur around implants which are peri-implant mucositis and periimplantitis. Peri-implant mucositis is pathological condition which is normally localized in the soft tissues surrounding an oral implant. Peri-implantitis surrounding oral implants is an inflammatory process affecting the soft and hard tissues resulting in rapid loss of supporting bone associated with b...

  8. Efter cochlear implant

    DEFF Research Database (Denmark)

    Højen, Anders

    2007-01-01

      Dit barn har netop fået et cochlear implant. Hvad nu? Skal barnet fokusere udelukkende på at lære talt sprog, eller skal det også lære/fortsætte med tegnsprog eller støttetegn? Det er et vanskeligt spørgsmål, og før valget foretages, er det vigtigt at vurdere hvilke konsekvenser valget har, dels...... for den sproglige udvikling isoleret set, og dels for barnets udvikling ud fra en helhedsbetragtning. Dette indlæg fokuserer på, hvilke forventninger man kan have til cochlear implant-brugeres sproglige udvikling med talt sprog alene, hhv. med to sprog (tale og tegn). Disse forventninger er baseret på...

  9. Efter cochlear implant

    DEFF Research Database (Denmark)

    Højen, Anders

    Dit barn har netop fået et cochlear implant. Hvad nu? Skal barnet fokusere udelukkende på at lære talt sprog, eller skal det også lære/fortsætte med tegnsprog eller støttetegn? Det er et vanskeligt spørgsmål, og før valget foretages, er det vigtigt at vurdere hvilke konsekvenser valget har, dels...... for den sproglige udvikling isoleret set, og dels for barnets udvikling ud fra en helhedsbetragtning. Dette indlæg fokuserer på, hvilke forventninger man kan have til cochlear implant-brugeres sproglige udvikling med talt sprog alene, hhv. med to sprog (tale og tegn). Disse forventninger er baseret på...

  10. Managing Joint Production Motivation

    DEFF Research Database (Denmark)

    Lindenberg, Siegwart; Foss, Nicolai Juul

    2011-01-01

    representations of actions and tasks; cognitively coordinate cooperation; and choose their own behaviors in terms of joint goals. Using goal-framing theory, we explain how motivation for joint production can be managed by cognitive/symbolic management and organizational design....

  11. JET Joint Undertaking

    International Nuclear Information System (INIS)

    The paper presents the progress report of the Joint European Torus (JET) Joint Undertaking, 1986. The report contains a survey of the scientific and technical achievements on JET during 1986; the more important articles referred to in this survey are reproduced as appendices to this Report. The last section discusses developments which might improve the overall performance of the machine. (U.K.)

  12. Creep of timber joints

    NARCIS (Netherlands)

    Van de Kuilen, J.W.G.

    2008-01-01

    A creep analysis has been performed on nailed, toothed-plates and split-ring joints in a varying uncontrolled climate. The load levels varied between 30% and 50% of the average ultimate short term strength of these joints, tested in accordance with ISO 6891. The climate in which the tests were perfo

  13. Opaque intraocular lens implantation

    OpenAIRE

    Yusuf IH; Patel CK

    2013-01-01

    Imran H Yusuf, CK Patel The Oxford Eye Hospital, West Wing, John Radcliffe Hospital, Headley Way, Headington, Oxford, United KingdomWe read with great interest the recent article by Lee et al,1 who described their clinical experience with three patients who underwent primary implantation of Morcher (Stuttgart, Germany) occlusive intraocular lenses (IOLs) across a variety of neuro-ophthalmic indications. We hope to offer some further insight into these clinical observations in the context of o...

  14. BP/Mobil. Joint-venture directions for use

    International Nuclear Information System (INIS)

    This paper analyzes the economical reasons which have led BP and Mobil companies to join their forces in 1996. Thanks to their complementarity and to their European implantation, the two companies could win the first or second position in petroleum products marketing in 8 European countries. The cumulated petrol sales and the number of petrol stations of the BP/Mobil joint venture are the highest in Europe (800 petrol stations in France). (J.S.)

  15. Bone Substitutes for Peri-Implant Defects of Postextraction Implants

    Directory of Open Access Journals (Sweden)

    Pâmela Letícia Santos

    2013-01-01

    Full Text Available Placement of implants in fresh sockets is an alternative to try to reduce physiological resorption of alveolar ridge after tooth extraction. This surgery can be used to preserve the bone architecture and also accelerate the restorative procedure. However, the diastasis observed between bone and implant may influence osseointegration. So, autogenous bone graft and/or biomaterials have been used to fill this gap. Considering the importance of bone repair for treatment with implants placed immediately after tooth extraction, this study aimed to present a literature review about biomaterials surrounding immediate dental implants. The search included 56 articles published from 1969 to 2012. The results were based on data analysis and discussion. It was observed that implant fixation immediately after extraction is a reliable alternative to reduce the treatment length of prosthetic restoration. In general, the biomaterial should be used to increase bone/implant contact and enhance osseointegration.

  16. Strategies for joint appointments.

    Science.gov (United States)

    Royle, J; Crooks, D L

    1985-01-01

    The structure and policies governing joint appointments discussed above, are developed primarily through cooperation and collaboration between nursing service and education institutions. The joint appointee participates in the process of negotiation of salary, benefits and role responsibilities and exploration of the implications of the appointment for personal career development. Implementation and maintenance of the appointment requires the collaborative efforts of the joint appointee with both contracting agencies. Factors influencing the functioning of joint appointees have been identified and strategies to facilitate functioning presented. The joint appointee must be independent in thought and action yet adaptable to work within the boundaries of two social systems with differing values and expectations. Nursing management, peers and students can provide the support needed to overcome the frustrations and to achieve the rewards inherent in successful implementation of an exciting and innovative role. PMID:3852805

  17. Strengthening of defected beam–column joints using CFRP

    Directory of Open Access Journals (Sweden)

    Mohamed H. Mahmoud

    2014-01-01

    Full Text Available This paper presents an experimental study for the structural performance of reinforced concrete (RC exterior beam–column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP. The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam–column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity.

  18. Strengthening of defected beam-column joints using CFRP.

    Science.gov (United States)

    Mahmoud, Mohamed H; Afefy, Hamdy M; Kassem, Nesreen M; Fawzy, Tarek M

    2014-01-01

    This paper presents an experimental study for the structural performance of reinforced concrete (RC) exterior beam-column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP). The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam-column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM) CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity. PMID:25685473

  19. The Synovial Lining and Synovial Fluid Properties after Joint Arthroplasty

    Directory of Open Access Journals (Sweden)

    Michael Shang Kung

    2015-05-01

    Full Text Available The lubrication of the cartilaginous structures in human joints is provided by a fluid from a specialized layer of cells at the surface of a delicate tissue called the synovial lining. Little is known about the characteristics of the fluids produced after a joint arthroplasty procedure. A literature review was carried out to identify papers that characterized the synovial lining and the synovial fluids formed after total hip or knee arthroplasty. Five papers about synovial lining histology and six papers about the lubricating properties of the fluids were identified. The cells making up the re-formed synovial lining, as well as the lining of interface membranes, were similar to the typical Type A and B synoviocytes of normal joints. The synovial fluids around joint replacement devices were typically lower in viscosity than pre-arthroplasty fluids but the protein concentration and phospholipid concentrations tended to be comparable, suggesting that the lining tissue function was preserved after arthroplasty. The widespread, long-term success of joint arthroplasty suggests that the lubricant formed from implanted joint synovium is adequate for good clinical performance in the majority of joints. The role the fluid plays in component wear or failure is a topic for future study.

  20. Strengthening of defected beam–column joints using CFRP

    Science.gov (United States)

    Mahmoud, Mohamed H.; Afefy, Hamdy M.; Kassem, Nesreen M.; Fawzy, Tarek M.

    2013-01-01

    This paper presents an experimental study for the structural performance of reinforced concrete (RC) exterior beam–column joints rehabilitated using carbon-fiber-reinforced polymer (CFRP). The present experimental program consists of testing 10 half-scale specimens divided into three groups covering three possible defects in addition to an adequately detailed control specimen. The considered defects include the absence of the transverse reinforcement within the joint core, insufficient bond length for the beam main reinforcement and inadequate spliced implanted column on the joint. Three different strengthening schemes were used to rehabilitate the defected beam–column joints including externally bonded CFRP strips and sheets in addition to near surface mounted (NSM) CFRP strips. The failure criteria including ultimate capacity, mode of failure, initial stiffness, ductility and the developed ultimate strain in the reinforcing steel and CFRP were considered and compared for each group for the control and the CFRP-strengthened specimens. The test results showed that the proposed CFRP strengthening configurations represented the best choice for strengthening the first two defects from the viewpoint of the studied failure criteria. On the other hand, the results of the third group showed that strengthening the joint using NSM strip technique enabled the specimen to outperform the structural performance of the control specimen while strengthening the joints using externally bonded CFRP strips and sheets failed to restore the strengthened joints capacity. PMID:25685473

  1. Contact mechanics of reverse engineered distal humeral hemiarthroplasty implants.

    Science.gov (United States)

    Willing, Ryan; King, Graham J W; Johnson, James A

    2015-11-26

    Erosion of articular cartilage is a concern following distal humeral hemiarthroplasty, because native cartilage surfaces are placed in contact with stiff metallic implant components, which causes decreases in contact area and increases in contact stresses. Recently, reverse engineered implants have been proposed which are intended to promote more natural contact mechanics by reproducing the native bone or cartilage shape. In this study, finite element modeling is used in order to calculate changes in cartilage contact areas and stresses following distal humeral hemiarthroplasty with commercially available and reverse engineered implant designs. At the ulna, decreases in contact area were -34±3% (p=0.002), -27±1% (pengineered and cartilage reverse engineered designs, respectively. Peak contact stresses increased by 461±57% (p=0.008), 387±127% (p=0.229) and 165±16% (p=0.003). At the radius, decreases in contact area were -21±3% (p=0.013), -13±2% (p0.999), 241±32% (p=0.010) and 61±10% (p=0.021). Between the three different implant designs, the cartilage reverse engineered design yielded the largest contact areas and lowest contact stresses, but was still unable to reproduce the contact mechanics of the native joint. These findings align with a growing body of evidence indicating that although reverse engineered hemiarthroplasty implants can provide small improvements in contact mechanics when compared with commercially available designs, further optimization of shape and material properties is required in order reproduce native joint contact mechanics.

  2. [Prosthetic dilemmas. Connecting natural teeth and implants

    NARCIS (Netherlands)

    Cune, M.S.; Putter, C de; Verhoeven, J.W.; Meijer, G.J.

    2008-01-01

    In clinical practice, the prognosis seems, with some reservations, to be comparable for tooth-implant and implant-implant supported bridges in the middle-long term.This conclusion seems particularly valid for tooth-implant bridges in free-end situations, where a single implant is connected with a to

  3. The change of rotational freedom following different insertion torques in three implant systems with implant driver

    OpenAIRE

    Kwon, Joo-Hyun; Han, Chong-Hyun; Kim, Sun-Jai; Chang, Jae-Seung

    2009-01-01

    STATEMENT OF PROBLEM Implant drivers are getting popular in clinical dentistry. Unlike to implant systems with external hex connection, implant drivers directly engage the implant/abutment interface. The deformation of the implant/abutment interface can be introduced while placing an implant with its implant driver in clinical situations. PURPOSE This study evaluated the change of rotational freedom between an implant and its abutment after application of different insertion torques. MATERIAL...

  4. The Evolution of Breast Implants.

    Science.gov (United States)

    Gabriel, Allen; Maxwell, G Patrick

    2015-10-01

    Breast augmentation remains one of the most common procedures performed in the United States. However, shape, feel, safety, and longevity of the implants remain important areas of research. The data provided by manufacturers show the safety and efficacy of these medical devices. Clinicians should strive to provide ongoing data and sound science to continue to improve clinical outcomes in the future. This article explores the evolution of breast implants with special emphasis on the advancement of silicone implants.

  5. Current trends in dental implants

    OpenAIRE

    Gaviria, Laura; Salcido, John Paul; Guda, Teja; Ong, Joo L.

    2014-01-01

    Tooth loss is very a very common problem; therefore, the use of dental implants is also a common practice. Although research on dental implant designs, materials and techniques has increased in the past few years and is expected to expand in the future, there is still a lot of work involved in the use of better biomaterials, implant design, surface modification and functionalization of surfaces to improve the long-term outcomes of the treatment. This paper provides a brief history and evoluti...

  6. Dental Implants: Dual Stabilization Technology

    OpenAIRE

    Saini, Rajiv

    2015-01-01

    More recent epidemiological data seem to show an increasing trend of tooth loss due to periodontal reasons rather than caries; the presence of initial attachment loss, bone height and the habit of smoking significantly increase the risk of tooth mortality. A dental implant is a titanium screw which is placed into bone to replace missing teeth. The implant mimics the root of a tooth in function. Dental Implants have changed the face of dentistry over the last three decades. Success of dental i...

  7. Short implants in oral rehabilitation

    OpenAIRE

    Emmanuel Panobianco Chizolini; Ana Cláudia Rossi; Alexandre Rodrigues Freire; Mario Roberto Perussi; Paulo Henrique Ferreira Caria; Felippe Bevilacqua Prado

    2011-01-01

    Introduction and objective: The placement of short dental implants is used as an alternative treatment modality to bone grafting procedures. The aim of this study was to discuss, through a literature review, the features, indications and biomechanical aspects of short implants, as well as to report the clinical factors that influence on their indication. Literature review and conclusion: It was found that short implants osseointegration can be compromised by risk factors that must be controll...

  8. Nanostructured Surfaces of Dental Implants

    OpenAIRE

    Stefano Sivolella; Barbara Zavan; Letizia Ferroni; Chiara Gardin; Vincenzo Vindigni; Edoardo Stellini; Marco Roman; Ilaria Tocco; Riccardo Guazzo; Luca Sbricoli; Eriberto Bressan

    2013-01-01

    The structural and functional fusion of the surface of the dental implant with the surrounding bone (osseointegration) is crucial for the short and long term outcome of the device. In recent years, the enhancement of bone formation at the bone-implant interface has been achieved through the modulation of osteoblasts adhesion and spreading, induced by structural modifications of the implant surface, particularly at the nanoscale level. In this context, traditional chemical and physical process...

  9. Cochlear implants in genetic deafness

    Institute of Scientific and Technical Information of China (English)

    Xuezhong Liu

    2014-01-01

    Genetic defects are one of the most important etiologies of severe to profound sensorineural hearing loss and play an important role in determining cochlear implantation outcomes. While the pathogenic mutation types of a number of deafness genes have been cloned, the pathogenesis mechanisms and their relationship to the outcomes of cochlear implantation remain a hot research area. The auditory performance is considered to be affected by the etiology of hearing loss and the number of surviving spiral ganglion cells, as well as others. Current research advances in cochlear implantation for hereditary deafness, especially the relationship among clinic-types, genotypes and outcomes of cochlear implantation, will be discussed in this review.

  10. Dental implants in growing children

    Directory of Open Access Journals (Sweden)

    S K Mishra

    2013-01-01

    Full Text Available The replacement of teeth by implants is usually restricted to patients with completed craniofacial growth. The aim of this literature review is to discuss the use of dental implants in normal growing patients and in patients with ectodermal dysplasia and the influence of maxillary and mandibular skeletal and dental growth on the stability of those implants. It is recommended that while deciding the optimal individual time point of implant insertion, the status of skeletal growth, the degree of hypodontia, and extension of related psychological stress should be taken into account, in addition to the status of existing dentition and dental compliance of a pediatric patient.

  11. Short implants: A systematic review

    OpenAIRE

    Karthikeyan, I.; Shrikar R. Desai; Singh, Rika

    2012-01-01

    Background: Short implants are manufactured for use in atrophic regions of the jaws. Although many studies report on short implants as ≤10 mm length with considerable success, the literature regarding survival rate of ≤7 mm is sparse. Purpose: The purpose of this study was to systematically evaluate the publications concerning short dental implants defined as an implant with a length of ≤7 mm placed in the maxilla or in the mandible. Materials and Methods: A Medline and manual search was cond...

  12. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications.

  13. The Stress Distribution on the Zygapophyseal Joint of Lumbar Vertebra by ANSYS Program

    Directory of Open Access Journals (Sweden)

    Summer S. M. Mukhtar

    2010-01-01

    Full Text Available Zygapophyseal joints (or facet joints, are a plane synovial joint which located between the articular facet processes of the vertebral arch which is freely guided movable joints. Ten dried vertebrae were used for the lumbar region and taking (L4 as a sample to reveal stress pathways across the joints by using ANSYS program under different loading conditions which used Finite Elements Analysis model. Results obtained from the ANSYS program are important in understanding the boundary conditions for load analysis and the points of stress concentration which explained from the anatomical point of view and linked to muscle and ligament attachments. This model used as a computational tool to joint biomechanics and to prosthetic implant analysis.

  14. The effect of ion implantation on the tribomechanical properties of carbon fibre reinforced polymers

    Energy Technology Data Exchange (ETDEWEB)

    Mistica, R.; Sood, D.K. [Royal Melbourne Inst. of Tech., VIC (Australia); Janardhana, M.N. [Deakin University, Geelong, VIC (Australia). School of Engineering and Technology

    1993-12-31

    Graphite fibre reinforced epoxy composite material (GFRP) is used extensively in the aerospace and other industries for structural application. The trend is to address the 20 to 30 year life endurance of this material in service. Mechanical joints in air crafts are exposed to dynamic loads during service and wear may be experienced by the composite material joint. Generally it has been shown that graphite fibre reinforced polymers have superior wear and friction properties as compared with the unfilled polymers. In the described experiment, ion implantation was used as a novel surface treatment. Wear and friction of a polymer composite material (GFRP) was studied and ion implantation was used in order to observe the effect on the tribomechanical properties of the material. It was found that ion implantation of C on GFRP sliding against Ti changes the tribological properties of the system, and in particular decreases the coefficient of friction and wear. 4 refs., 2 figs.

  15. Delayed breast implant reconstruction

    DEFF Research Database (Denmark)

    Hvilsom, Gitte B.; Hölmich, Lisbet R.; Steding-Jessen, Marianne;

    2012-01-01

    We evaluated the association between radiation therapy and severe capsular contracture or reoperation after 717 delayed breast implant reconstruction procedures (288 1- and 429 2-stage procedures) identified in the prospective database of the Danish Registry for Plastic Surgery of the Breast during...... of radiation therapy was associated with a non-significantly increased risk of reoperation after both 1-stage (HR = 1.4; 95% CI: 0.7-2.5) and 2-stage (HR = 1.6; 95% CI: 0.9-3.1) procedures. Reconstruction failure was highest (13.2%) in the 2-stage procedures with a history of radiation therapy. Breast...

  16. Hip joint replacement

    Science.gov (United States)

    ... may have problems with infection, loosening, or even dislocation of the new hip joint. Over time the artificial ... Professor, Chief, Sports Medicine and Shoulder Service, UCSF Department of Orthopaedic Surgery, San Francisco, ...

  17. Joint Injection/Aspiration

    Science.gov (United States)

    ... Working It Out: Common Techniques for Conflict Resolution Workplace Diversity & Team Performance CME & MOC Understanding MOC ACR's MOC ... infection is suspected, aspirating the joint to gather cultures is ... Communications and Marketing. This patient information is provided for ...

  18. MP Joint Arthritis

    Science.gov (United States)

    ... Therapist? Media Find a Hand Surgeon MP Joint Arthritis Email to a friend * required fields From * To * ... in to name and customize your collection. DESCRIPTION Arthritis is the wearing away of the cartilage at ...

  19. Temporomandibular Joint Disorder

    Science.gov (United States)

    ... 2008 Previous Next Related Articles: Temporomandibular Joint Disorder (TMD) Are You Biting Off More Than You Can Chew? Equilibration May Lessen TMD Pain Fender-benders: Source of TMD? First Comes ...

  20. Healthy Joints Matter

    Science.gov (United States)

    ... dietary supplements, such as green tea and various vitamins, to see if they can keep your joints ... body, such as your ears, nose, and windpipe. Fibromyalgia (fi-bro-my-AL-juh). A condition that ...

  1. Joint Quantum Institute

    Data.gov (United States)

    Federal Laboratory Consortium — The Joint Quantum Institute (JQI) is pursuing that goal through the work of leading quantum scientists from the Department of Physics of the University of Maryland...

  2. The design and development of a finger joint simulator.

    Science.gov (United States)

    Joyce, Thomas J

    2016-05-01

    Artificial finger joints lack the long-term clinical success seen with hip and knee prostheses. In part, this can be explained by the challenges of rheumatoid arthritis, a progressive disease which attacks surrounding tissues as well as the joint itself. Therefore, the natural finger joints' biomechanics are adversely affected, and consequently, this imbalance due to subluxing forces further challenges any prosthesis. Many different designs of finger prosthesis have been offered over a period of greater than 50 years. Most of these designs have failed, and it is likely that many of these failures could have been identified had the prostheses been appropriately tested prior to implantation into patients. While finger joint simulators have been designed, arguably only those from a single centre have been able to reproduce clinical-type failures of the finger prostheses tested in them. This article describes the design and development of a finger simulator at Durham University, UK. It explains and justifies the engineering decisions made and thus the evolution of the finger simulator. In vitro results and their linkage to clinical-type failures are outlined to help to show the effectiveness of the simulator. Failures of finger implants in vivo continue to occur, and the need for appropriate in vitro testing of finger prostheses remains strong. PMID:26833697

  3. The design and development of a finger joint simulator.

    Science.gov (United States)

    Joyce, Thomas J

    2016-05-01

    Artificial finger joints lack the long-term clinical success seen with hip and knee prostheses. In part, this can be explained by the challenges of rheumatoid arthritis, a progressive disease which attacks surrounding tissues as well as the joint itself. Therefore, the natural finger joints' biomechanics are adversely affected, and consequently, this imbalance due to subluxing forces further challenges any prosthesis. Many different designs of finger prosthesis have been offered over a period of greater than 50 years. Most of these designs have failed, and it is likely that many of these failures could have been identified had the prostheses been appropriately tested prior to implantation into patients. While finger joint simulators have been designed, arguably only those from a single centre have been able to reproduce clinical-type failures of the finger prostheses tested in them. This article describes the design and development of a finger simulator at Durham University, UK. It explains and justifies the engineering decisions made and thus the evolution of the finger simulator. In vitro results and their linkage to clinical-type failures are outlined to help to show the effectiveness of the simulator. Failures of finger implants in vivo continue to occur, and the need for appropriate in vitro testing of finger prostheses remains strong.

  4. Joint Venture Contracts

    OpenAIRE

    Pimentel, Dinarco

    2015-01-01

    Joint Venture contracts are contracting models typically designed to reach international markets. In spite of being used at the national level, a joint venture is based on single or multiple contracts between two individuals, two institutions, two organizations or two different entrepreneurial entities joining forces, meeting synergies to reach a common goal.Initially, these types of contracts were justifiable based on the need of different economic agents penetrating the most inaccessible ma...

  5. Joint contingency contracting

    OpenAIRE

    Johnson, Ellsworth K.; Paton, Bryan H.; Threat, Edward W.; Haptonstall, Lisa A.

    2005-01-01

    The purpose of this Master of Business Administration (MBA) Professional Report is to investigate and analyze the means by which Contingency Contracting Officers (CCO) can effectively operate in a Joint contingency environment and to validate the Defense Contract Management Agency's (DCMA) entry and exit criteria for contingency contracting missions. Joint contingencies encompass regional conflicts, humanitarian and peacekeeping missions, and international or domestic disaster relief missions...

  6. Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (BHRS), British Cardiovascular Society (BCS), British Heart Valve Society (BHVS) and British Society for Echocardiography (BSE).

    Science.gov (United States)

    Sandoe, Jonathan A T; Barlow, Gavin; Chambers, John B; Gammage, Michael; Guleri, Achyut; Howard, Philip; Olson, Ewan; Perry, John D; Prendergast, Bernard D; Spry, Michael J; Steeds, Richard P; Tayebjee, Muzahir H; Watkin, Richard

    2015-02-01

    Infections related to implantable cardiac electronic devices (ICEDs), including pacemakers, implantable cardiac defibrillators and cardiac resynchronization therapy devices, are increasing in incidence in the USA and are likely to increase in the UK, because more devices are being implanted. These devices have both intravascular and extravascular components and infection can involve the generator, device leads and native cardiac structures or various combinations. ICED infections can be life-threatening, particularly when associated with endocardial infection, and all-cause mortality of up to 35% has been reported. Like infective endocarditis, ICED infections can be difficult to diagnose and manage. This guideline aims to (i) improve the quality of care provided to patients with ICEDs, (ii) provide an educational resource for all relevant healthcare professionals, (iii) encourage a multidisciplinary approach to ICED infection management, (iv) promote a standardized approach to the diagnosis, management, surveillance and prevention of ICED infection through pragmatic evidence-rated recommendations, and (v) advise on future research projects/audit. The guideline is intended to assist in the clinical care of patients with suspected or confirmed ICED infection in the UK, to inform local infection prevention and treatment policies and guidelines and to be used in the development of educational and training material by the relevant professional societies. The questions covered by the guideline are presented at the beginning of each section.

  7. The results of application of anterior cruciate ligament two-bundle plastics by synthetic implant in its complete tears

    Directory of Open Access Journals (Sweden)

    Shormanov A.M.

    2015-12-01

    Full Text Available Objective: to improve surgical results of patients with complete tears of anterior cruciate ligament by synthetic implant Don-M. Materials and Methods. 7 patients with ACL complete tear who underwent two-bundle plastics with synthetic en-doprosthetic implant Don-M were investigated. Results. The application of ACL two-bundle plastics with synthetic Don-M implant allowed reaching complete knee joint stability during the first several hours after surgery and completely restore knee joint motion range in the course of 6 months. Conclusion. The application of ACL two-bundle plastics is anatomically justified and provides knee joint stability as well as early activation and rehabilitation opportunities.

  8. High pressure ceramic joint

    Science.gov (United States)

    Ward, Michael E.; Harkins, Bruce D.

    1993-01-01

    Many recuperators have components which react to corrosive gases and are used in applications where the donor fluid includes highly corrosive gases. These recuperators have suffered reduced life, increased service or maintenance, and resulted in increased cost. The present joint when used with recuperators increases the use of ceramic components which do not react to highly corrosive gases. Thus, the present joint used with the present recuperator increases the life, reduces the service and maintenance, and reduces the increased cost associated with corrosive action of components used to manufacture recuperators. The present joint is comprised of a first ceramic member, a second ceramic member, a mechanical locking device having a groove defined in one of the first ceramic member and the second ceramic member. The joint and the mechanical locking device is further comprised of a refractory material disposed in the groove and contacting the first ceramic member and the second ceramic member. The present joint mechanically provides a high strength load bearing joint having good thermal cycling characteristics, good resistance to a corrosive environment and good steady state strength at elevated temperatures.

  9. Management of dislocated intraocular implants.

    Science.gov (United States)

    Chan, C K; Agarwal, A; Agarwal, S; Agarwal, A

    2001-12-01

    Implant dislocation may occur in the absence of appropriate capsular or zonular support (PCIOL) (11,35,53) or following traumatic injury to anterior ocular tissues (ACIOL). (11,19,20) Other factors (e.g., advanced patient age, high myopia, previous vitrectomy, pseudoexfoliation syndrome, and certain connective tissue disorders) also may predispose implant dislocation. (9,52) Although reported for all types of IOLs, implant dislocation is becoming more manageable because of the advancement of surgical techniques. A dislocated ACIOL or PCIOL may be explanted, exchanged, or repositioned. (11,48,71) Repositioning the dislocated PCIOL in the ciliary sulcus with modern vitreoretinal techniques provides an optimal environment for visual recovery. (11,71) Implant repositioning techniques generally may be categorized into the external or the internal approaches. (8,11) The former involves external suturing methods for a primary or secondary implant in the absence of adequate capsular or zonular support (15,16,31,42,56,60,61,64,66,73,76) and the latter is achieved through modern pars plana techniques. 8,11,62,69) Recently, several implant repositioning methods gaining increasing acceptance include the scleral loop fixation, (45) the snare approach, (43) the use of the 25-gauge implant forceps, (13) temporary haptic externalization, (8,11,36,71) and the use of perfluorocarbon liquids. (1,28,40,41,44) The temporary haptic externalization method combines the best features of the external and the internal approaches, avoids complex intraocular maneuvers, and allows precise scleral fixation of the dislocated IOL on a consistent basis. (8,11,71) Endoscopy provides the surgeon with optimal viewing of the anterior retropupillary anatomy that is often difficult to appreciate (e.g., capsular-zonular complex, ciliary sulcus, anterior retina, and vitreous base). (6,11) As a result, precise haptic placement is possible during the repositioning process. (6,11) However, a three

  10. Implant periapical lesion: Diagnosis and treatment

    OpenAIRE

    Peñarrocha Diago, María; Maestre Ferrín, Laura; Cervera Ballester, Juan; Peñarrocha Oltra, David

    2012-01-01

    The implant periapical lesion is the infectious-inflammatory process of the tissues surrounding the implant apex. It may be caused by different factors: contamination of the implant surface, overheating of bone during drilling, preparation of a longer implant bed than the implant itself, and pre-existing bone disease. Diagnosis is achieved by studying the presence of symptoms and signs such us pain, swelling, suppuration or fistula; in the radiograph an implant periapical radiolucency may app...

  11. Piezosurgery in implant dentistry

    Directory of Open Access Journals (Sweden)

    Stübinger S

    2015-11-01

    Full Text Available Stefan Stübinger,1 Andres Stricker,2 Britt-Isabelle Berg3,4 1Hightech Research Center of Cranio-maxillofacial Surgery, University of Basel, Allschwil, Switzerland; 2Private Practice, Konstanz, Germany; 3Department of Cranio-maxillofacial Surgery, University Hospital Basel, Basel, Switzerland; 4Division of Oral and Maxillofacial Radiology, Columbia University Medical Center, New York, NY, USA Abstract: Piezosurgery, or the use of piezoelectric devices, is being applied increasingly in oral and maxillofacial surgery. The main advantages of this technique are precise and selective cuttings, the avoidance of thermal damage, and the preservation of soft-tissue structures. Through the application of piezoelectric surgery, implant-site preparation, bone grafting, sinus-floor elevation, edentulous ridge splitting or the lateralization of the inferior alveolar nerve are very technically feasible. This clinical overview gives a short summary of the current literature and outlines the advantages and disadvantages of piezoelectric bone surgery in implant dentistry. Overall, piezoelectric surgery is superior to other methods that utilize mechanical instruments. Handling of delicate or compromised hard- and soft-tissue conditions can be performed with less risk for the patient. With respect to current and future innovative surgical concepts, piezoelectric surgery offers a wide range of new possibilities to perform customized and minimally invasive osteotomies. Keywords: implantology, piezoelectric device, piezosurgery, maxillary sinus elevation, bone grafting, osteotomy, edentulous ridge splitting

  12. Endometrium implantation and ectopic pregnancy

    Institute of Scientific and Technical Information of China (English)

    LIU; Yixun

    2004-01-01

    Embryo in uterine implantation is a complex and multifactor-related process and is a downstream and ideal point for woman fertility control.Understanding the cellular and molecular mechanism of implantation is a prerequisite for development of anti-implantation contraceptives.In spite of considerable accumulation of information from the laboratory animals that has been achieved,it is difficult to generate such information in human due to ethical restriction and experimental limitation,and the present knowledge for understanding the definitive mechanisms which control these events remains elusive.Embryo implantation can also occur outside uterus.Some women with abdominal pregnancies could successfully complete the processes of gestation and bear normal babies,implying that implantation itself may be not an endometrium-specific process.Reproductive biologists should cooperate with gynecologists to further comparatively study the molecular and cellular mechanisms of implantation normally occurring in endometrium and abnormally appearing outside uterine cavity.Such collaborative studies may generate new important information for developing anti-implantation contraceptive and for techniques of accurate diagnosis of ectopic pregnancy.A specially designed GnRH-2 analog and a combination use of Iow dose RU486 and gossypol as anti-implantation contraceptives have been suggested.

  13. NEGATIVE IMPLANT - A RETROSPECTIVE STUDY

    NARCIS (Netherlands)

    LANDESZ, M; WORST, JGF; SIERTSEMA, JV; VANRIJ, G

    1993-01-01

    Implantation of a negative power intraocular lens is one of the options for surgical correction of high myopia. We studied 36 eyes with a Fechner Worst Claw Lens, implanted in Groningen between March 1987 and November 1991. The preoperative myopia ranged from -7.00 to -30.00 diopters. Twentyone eyes

  14. Implantable Antennas for Biomedical Applications

    OpenAIRE

    Merli, Francesco

    2011-01-01

    Since the introduction of implantable pacemakers in the early 1960s, implantable medical devices have become more and more interesting for healthcare services. Nowadays, the devices designed to monitor physiological data from inside the human body have great promises to provide major contributions to disease prevention, diagnosis and therapy. Furthermore, minimally invasive devices allow reducing hospitalization terms, thus improving the patients' qua...

  15. Short implants in oral rehabilitation

    Directory of Open Access Journals (Sweden)

    Emmanuel Panobianco Chizolini

    2011-07-01

    Full Text Available Introduction and objective: The placement of short dental implants is used as an alternative treatment modality to bone grafting procedures. The aim of this study was to discuss, through a literature review, the features, indications and biomechanical aspects of short implants, as well as to report the clinical factors that influence on their indication. Literature review and conclusion: It was found that short implants osseointegration can be compromised by risk factors that must be controlled to achieve treatment success. In conclusion, the main indication of short implants is to avoid an invasive surgery at atrophic areas of maxilla and mandible. Furthermore, implant design associated with surface treatment are factors that compensate its short length.

  16. [Dental implants in tooth grinders].

    Science.gov (United States)

    Lobbezoo, F; Brouwers, J E; Cune, M S; Naeije, M

    2004-03-01

    Bruxism (tooth grinding and clenching) is generally considered a contraindication for dental implants, although the evidence is usually based on clinical experience only. So far, studies to the possible cause-and-effect relationship between bruxism and implant failure do not yield consistent and specific outcomes. This is partly due to the large variation in the technical and the biological aspects of the investigations. Although there is still no proof that bruxism causes overload of dental implants and their suprastructures, a careful approach is recommended. Practical advices as to minimize the chance of implant failure are given. Besides the recommendation to reduce or eliminate bruxism itself, these advices concern the number and dimensions of the implants, the design of the occlusion and articulation patterns, and the use of a hard nightguard. PMID:15058243

  17. [Biomechanics of the ankle joint].

    Science.gov (United States)

    Zwipp, H

    1989-03-01

    According to Fick, the tree-dimensional patterns of foot motion are best characterized as jawlike movement. Anatomically and biomechanically, this process represents conjoined, synchronous motion within the three mobile segments of the hindfoot: the ankle joint, the posterior subtalar joint, and the anterior subtalar joint. Foot kinematics can be described more completely if the anterior subtalar joint is defined not only as the talocalcaneal navicular joint, but as including the calcaneocuboid joint, thus representing the transverse joint of the tarsus, i.e., the Chopart joint. The axes of these three joints can be defined precisely. In some parts they represent a screwlike motion, clockwise or counter-clockwise, around the central ligamentous structures (fibulotibial ligament, talocalcaneal interosseous ligament, bifurcate ligament). The individual anatomy and structure of these ligaments provide variations in the degree and direction of foot motion. A precise knowledge of foot kinematics is important in surgical ligament and joint reconstruction and in selective foot arthrodeses.

  18. REGENERATION OF ARTICULAR CARTILAGE UNDER THE IMPLANTATION OF BONE MATRIX

    Directory of Open Access Journals (Sweden)

    Yuri M. Iryanov, Nikolay A. Kiryanov, Olga V. Dyuriagina , Tatiana Yu. Karaseva, Evgenii A. Karasev

    2015-07-01

    Full Text Available Background: The damage or loss of articular cartilage is costly medical problem. The purpose of this work – morphological analysis of reparative chondrogenesis when implanted in the area of the knee joint cartilage of granulated mineralized bone matrix. Material and Methods: The characteristic features of the knee cartilage regeneration studied experimentally in pubertal Wistar rats after modeling a marginal perforated defect and implantation of granulated mineralized bone matrix obtained according to original technology without heat and demineralizing processing into the injury zone. Results: This biomaterial established to have pronounced chondro- and osteoinductive properties, and to provide prolonged activation of reparative process, accelerated organotypical remodeling and restoration of the articular cartilage injured. Conclusion: The data obtained demonstrate the efficacy of МВМ in clinical practice for the treatment of diseases and injuries of the articular cartilage.

  19. Porous polymers for repair and replacement of the knee joint meniscus and articular cartilage

    NARCIS (Netherlands)

    Klompmaker, Jan

    1992-01-01

    The studies presented here were initiated to answer a variety of questions concerning firstly the repair and replacement of the knee joint meniscus and, secondly, the repair of full-thickness defects of articular cartilage. AIMS OF THE STUDIES I To assess the effect of implantation of a porous polym

  20. 21 CFR 888.3200 - Finger joint metal/metal constrained uncemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3200 Section 888.3200 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained uncemented prosthesis. (a) Identification. A finger joint metal/metal constrained uncemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal...

  1. 21 CFR 888.3400 - Hip joint femoral (hemi-hip) metallic resurfacing prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3400 Section 888.3400 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... femoral (hemi-hip) metallic resurfacing prosthesis. (a) Identification. A hip joint femoral (hemi-hip) metallic resurfacing prosthesis is a device intended to be implanted to replace a portion of the hip...

  2. 21 CFR 888.3210 - Finger joint metal/metal constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3210 Section 888.3210 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/metal constrained cemented prosthesis. (a) Identification. A finger joint metal/metal constrained cemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal (finger)...

  3. 21 CFR 888.3220 - Finger joint metal/polymer constrained cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3220 Section 888.3220 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... metal/polymer constrained cemented prosthesis. (a) Identification. A finger joint metal/polymer constrained cemented prosthesis is a device intended to be implanted to replace a metacarpophalangeal...

  4. 21 CFR 888.3370 - Hip joint (hemi-hip) acetabular metal cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... prosthesis. 888.3370 Section 888.3370 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND... (hemi-hip) acetabular metal cemented prosthesis. (a) Identification. A hip joint (hemi-hip) acetabular metal cemented prosthesis is a device intended to be implanted to replace a portion of the hip...

  5. Joint ventures in medical services.

    Science.gov (United States)

    Rublee, D A

    1987-01-01

    This paper is an overview of joint-venture activity in healthcare, describing trends in joint ventures and raising issues for physicians. The purposes are to discuss the major current facets of joint-venture alliances in healthcare and to identify policy issues that arise from the trend to use joint ventures as an organizational tool. Speculation is made about the future role of joint ventures in the organization of healthcare.

  6. The temporomandibular joint

    International Nuclear Information System (INIS)

    Whilst the temporomandibular joint is in many ways unique, it is subject to all the diseases and disorders found in joints in other parts of the human skeleton. By far the most common disorder is injury, followed by arthropathy, acute and chronic dislocations, ankylosis, and in rare instances, neoplasms. The diagnosis and management of the temporomandibular joint are the primary responsibility of the oral surgeon. Nevertheless, this anatomical region is an area in which the cooperation of medical and dental disciplines may be required for the satisfactory conclusion of treatment. The more so when the disease process involves either associated psychosomatic illness or malignancy. The mainstay of the diagnosis is a careful radiological examination of the joint. There exists a delicate relationship between the dentition, the muscles of mastication, and the temporomandibular articulation, which is controlled by arthrokinetic reflex activity of the branches of the 5th cranial nerve. Imbalance between one or more of the components of this integrated system frequently leads to disturbances in function. Pain-dysfunction disorders constitute the larger part of temporomandibular joint disturbances generally encountered

  7. Distal radioulnar joint injuries

    Directory of Open Access Journals (Sweden)

    Binu P Thomas

    2012-01-01

    Full Text Available Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint , forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments.The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis.

  8. Dissimilar metals joint evaluation

    Science.gov (United States)

    Wakefield, M. E.; Apodaca, L. E.

    1974-01-01

    Dissimilar metals tubular joints between 2219-T851 aluminum alloy and 304L stainless steel were fabricated and tested to evaluate bonding processes. Joints were fabricated by four processes: (1) inertia (friction) weldings, where the metals are spun and forced together to create the weld; (2) explosive welding, where the metals are impacted together at high velocity; (3) co-extrusion, where the metals are extruded in contact at high temperature to promote diffusion; and (4) swaging, where residual stresses in the metals after a stretching operation maintain forced contact in mutual shear areas. Fifteen joints of each type were prepared and evaluated in a 6.35 cm (2.50 in.) O.D. size, with 0.32 cm (0.13 in.) wall thickness, and 7.6 cm (3.0 in) total length. The joints were tested to evaluate their ability to withstand pressure cycle, thermal cycle, galvanic corrosion and burst tests. Leakage tests and other non-destructive test techniques were used to evaluate the behavior of the joints, and the microstructure of the bond areas was analyzed.

  9. Temporomandibular joint examination reviewed

    Directory of Open Access Journals (Sweden)

    L. Guarda Nardini

    2011-09-01

    Full Text Available The temporo-mandibular joint (TMJ it’s a joint closely related to the skull base, the spine, and the jaws; all these anatomical structures must be taken in consideration when evaluating pain involving the tmj. In order to detect patients affected by pathology or dysfunctions of the tmj, physical examination is of great value in orienting the diagnosis. Inspection must consider the symmetry of the body, the dental status and the type of occlusion. Palpation is a way to assess contractiont involving the muscles of the masticatory system and of the neck. Auscultation, based on articular noise provides means to determine whether we are dealing with degeneration of the joint or a dislocation of the intrarticular disc. In order to confirm the diagnosis obtained with the clinical evaluation, it’s useful to perform imaging techniques as opt, tomography and TC of the tmj and electromyokineosiography – index of the mandibular functionality and of the muscles status. MRI and dynamic MRI are among the non invasive exams which give the greatest amount of information, regarding the disc position and the joint degeneration. Arthroscopy is an invasive technique that allows early diagnosis of degeneration and is helpful to reveal early inflammatory processes of the joint.

  10. Distal radioulnar joint injuries.

    Science.gov (United States)

    Thomas, Binu P; Sreekanth, Raveendran

    2012-09-01

    Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint, forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments. The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis. PMID:23162140

  11. Implantable, multifunctional, bioresorbable optics.

    Science.gov (United States)

    Tao, Hu; Kainerstorfer, Jana M; Siebert, Sean M; Pritchard, Eleanor M; Sassaroli, Angelo; Panilaitis, Bruce J B; Brenckle, Mark A; Amsden, Jason J; Levitt, Jonathan; Fantini, Sergio; Kaplan, David L; Omenetto, Fiorenzo G

    2012-11-27

    Advances in personalized medicine are symbiotic with the development of novel technologies for biomedical devices. We present an approach that combines enhanced imaging of malignancies, therapeutics, and feedback about therapeutics in a single implantable, biocompatible, and resorbable device. This confluence of form and function is accomplished by capitalizing on the unique properties of silk proteins as a mechanically robust, biocompatible, optically clear biomaterial matrix that can house, stabilize, and retain the function of therapeutic components. By developing a form of high-quality microstructured optical elements, improved imaging of malignancies and of treatment monitoring can be achieved. The results demonstrate a unique family of devices for in vitro and in vivo use that provide functional biomaterials with built-in optical signal and contrast enhancement, demonstrated here with simultaneous drug delivery and feedback about drug delivery with no adverse biological effects, all while slowly degrading to regenerate native tissue. PMID:23150544

  12. Implant materials modified by colloids

    Directory of Open Access Journals (Sweden)

    Zboromirska-Wnukiewicz Beata

    2016-03-01

    Full Text Available Recent advances in general medicine led to the development of biomaterials. Implant material should be characterized by a high biocompatibility to the tissue and appropriate functionality, i.e. to have high mechanical and electrical strength and be stable in an electrolyte environment – these are the most important properties of bioceramic materials. Considerations of biomaterials design embrace also electrical properties occurring on the implant-body fluid interface and consequently the electrokinetic potential, which can be altered by modifying the surface of the implant. In this work, the surface of the implants was modified to decrease the risk of infection by using metal colloids. Nanocolloids were obtained using different chemical and electrical methods. It was found that the colloids obtained by physical and electrical methods are more stable than colloids obtained by chemical route. In this work the surface of modified corundum implants was investigated. The implant modified by nanosilver, obtained by electrical method was selected. The in vivo research on animals was carried out. Clinical observations showed that the implants with modified surface could be applied to wounds caused by atherosclerotic skeleton, for curing the chronic and bacterial inflammations as well as for skeletal reconstruction surgery.

  13. Total ankle joint replacement.

    Science.gov (United States)

    2016-02-01

    Ankle arthritis results in a stiff and painful ankle and can be a major cause of disability. For people with end-stage ankle arthritis, arthrodesis (ankle fusion) is effective at reducing pain in the shorter term, but results in a fixed joint, and over time the loss of mobility places stress on other joints in the foot that may lead to arthritis, pain and dysfunction. Another option is to perform a total ankle joint replacement, with the aim of giving the patient a mobile and pain-free ankle. In this article we review the efficacy of this procedure, including how it compares to ankle arthrodesis, and consider the indications and complications. PMID:26868932

  14. 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

  15. Microsystems Technology for Retinal Implants

    Science.gov (United States)

    Weiland, James

    2005-03-01

    The retinal prosthesis is targeted to treat age-related macular degeneration, retinitis pigmentosa, and other outer retinal degenerations. Simulations of artificial vision have predicted that 600-1000 individual pixels will be needed if a retinal prosthesis is to restore function such as reading large print and face recognition. An implantable device with this many electrode contacts will require microsystems technology as part of its design. An implantable retinal prosthesis will consist of several subsystems including an electrode array and hermetic packaging. Microsystems and microtechnology approaches are being investigated as possible solutions for these design problems. Flexible polydimethylsiloxane (PDMS) substrate electrode arrays and silicon micromachined electrode arrays are under development. Inactive PDMS electrodes have been implanted in 3 dogs to assess mechanical biocompatibility. 3 dogs were followed for 6 months. The implanted was securely fastened to the retina with a single retinal tack. No post-operative complications were evident. The array remained within 100 microns of the retinal surface. Histological evaluation showed a well preserved retina underneath the electrode array. A silicon device with electrodes suspended on micromachined springs has been implanted in 4 dogs (2 acute implants, 2 chronic implants). The device, though large, could be inserted into the eye and positioned on the retina. Histological analysis of the retina from the spring electrode implants showed that spring mounted posts penetrated the retina, thus the device will be redesigned to reduce the strength of the springs. These initial implants will provide information for the designers to make the next generation silicon device. We conclude that microsystems technology has the potential to make possible a retinal prosthesis with 1000 individual contacts in close proximity to the retina.

  16. Basic research on maxillofacial implants

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Yoshiro [Showa Univ., Tokyo (Japan). School of Dentistry

    2001-11-01

    Osseointegrated implants have begun to be used not only in general practice in dentistry but also in various clinical situations in the maxillofacial region. The process has yielded three problems: the spread of application, new materials and diagnostic methods, and management for difficult situations. This paper presents basic data and clinical guidelines for new applications, it investigates the characteristics of the materials and the usefulness of a new diagnostic method, and it studies effective techniques for difficult cases. The results obtained are as follows: Investigations into the spreading application. The lateral and superior orbital rim have sufficient bone thickness and width for the implant body to be placed. Osseointegrated implants, especially by the fixed bridge technique, are not recommended in the craniofacial bone and jaws of young children. Implant placement into bone after/before irradiation must be performed in consideration of impaired osteogenesis, the decrease of trabecular bone, and the time interval between implantation and irradiation. Investigations into materials and diagnostic methods. Hydroxyapatite-coated and titanium implants should be selected according to the characteristics of the materials. A dental simulating soft may also be applicable in the craniofacial region. Investigations into the management of difficult cases. Hyperbaric oxygen therapy (HBO), bone morphogenetic protein (BMP), and tissue engineering should be useful for improving the quality and increasing the quantity of bone where implants are placed. Soft tissue around implants placed in the reconstructed area should be replaced with mucosal tissue. The data obtained here should be useful for increasing the efficiency of osseointegrated implants, but further basic research is required in the future. (author)

  17. Studies of welded joints

    Directory of Open Access Journals (Sweden)

    J. M. Krupa

    2010-07-01

    Full Text Available Studies of a welded joint were described. The joint was made as a result of the reconstruction of a truss and one of the possible means to make a repair. The studies were of a simulation character and were targeted at the detection of welding defects and imperfections thatshould be eliminated in a real structure. A model was designed and on this model the tests and examinations were carried out. The modelwas made under the same conditions as the conditions adopted for repair. It corresponded to the real object in shape and dimensions, and in the proposed technique of welding and welding parameters. The model was composed of five plates joined together with twelve beads.The destructive and non-destructive tests were carried out; the whole structure and the respective welds were also examined visually. Thedefects and imperfections in welds were detected by surface methods of inspection, penetration tests and magnetic particle flaw detection.The model of the welded joint was prepared by destructive methods, a technique that would never be permitted in the case of a realstructure. For the investigations it was necessary to cut out the specimens from the welded joint in direction transverse to the weld run. The specimens were subjected to metallographic examinations and hardness measurements. Additionally, the joint cross-section was examined by destructive testing methods to enable precise determination of the internal defects and imperfections. The surface methods were applied again, this time to determine the severity of welding defects. The analysis has proved that, fabricated under proper conditions and with parameters of the welding process duly observed, the welded joint has good properties and repairs of this type are possible in practice.

  18. Simple facet joint repair with dynamic pedicular system: Technical note and case series

    Directory of Open Access Journals (Sweden)

    Ali Fahir Ozer

    2015-01-01

    Full Text Available Purpose: Facet joints are important anatomical structures for the stability of spine. Surgical or degenerative damage to a facet joint may lead to spinal instability and causes clinical problems. This article explains the importance of facet joints, reviews facet replacement systems, and describes a simple and effective method for facet replacement after surgical removal of facet joints. Materials and Methods: Ten patients were operated with the diagnosis of unilateral nerve root compression secondary to facet degeneration. The hypertrophic facet joints were removed with microsurgical techniques and the roots were decompressed. Then, a unilateral artificial facet joint was created using two hinged screws and a dynamic rod. Results: The clinical outcome of all the patients was determined good or excellent at second and last follow-up (mean 13.3 months controls using visual analog scale (VAS and Oswestry Disability Index (ODI scores. Radiological evaluations also demonstrated no implant-related complications. Conclusions: The authors suggest that, if removal of a facet joint is necessary to decompress the nerve roots, the joint can be replaced by a construct composed of two hinged screws connected by a dynamic rod. This simple system mimics the function of a normal facet joint and is an effective technique for unilateral facet joint replacement.

  19. Transversely Compressed Bonded Joints

    DEFF Research Database (Denmark)

    Hansen, Christian Skodborg; Schmidt, Jacob Wittrup; Stang, Henrik

    2012-01-01

    The load capacity of bonded joints can be increased if transverse pressure is applied at the interface. The transverse pressure is assumed to introduce a Coulomb-friction contribution to the cohesive law for the interface. Response and load capacity for a bonded single-lap joint was derived using...... non-linear fracture mechanics. The results indicated a good correlation between theory and tests. Furthermore, the model is suggested as theoretical base for determining load capacity of bonded anchorages with transverse pressure, in externally reinforced concrete structures....

  20. Silicone breast implants and platinum.

    Science.gov (United States)

    Wixtrom, Roger N

    2007-12-01

    Platinum, in a specific form, is used as a catalyst in the cross-linking reactions of the silicone gel and elastomer in breast implants. After manufacture, it remains in the devices at low-parts-per-million levels. Potential concerns have been raised as to whether this platinum might diffuse from silicone breast implants into the body and result in adverse health effects. The weight of evidence indicates that the platinum present is in its most biocompatible (zero valence) form, and the very minute levels (<0.1 percent) that might diffuse from the implants do not represent a significant health risk to patients. PMID:18090821

  1. Pediatric cochlear implantation: an update.

    Science.gov (United States)

    Vincenti, Vincenzo; Bacciu, Andrea; Guida, Maurizio; Marra, Francesca; Bertoldi, Barbara; Bacciu, Salvatore; Pasanisi, Enrico

    2014-01-01

    Deafness in pediatric age can adversely impact language acquisition as well as educational and social-emotional development. Once diagnosed, hearing loss should be rehabilitated early; the goal is to provide the child with maximum access to the acoustic features of speech within a listening range that is safe and comfortable. In presence of severe to profound deafness, benefit from auditory amplification cannot be enough to allow a proper language development. Cochlear implants are partially implantable electronic devices designed to provide profoundly deafened patients with hearing sensitivity within the speech range. Since their introduction more than 30 years ago, cochlear implants have improved their performance to the extent that are now considered to be standard of care in the treatment of children with severe to profound deafness. Over the years patient candidacy has been expanded and the criteria for implantation continue to evolve within the paediatric population. The minimum age for implantation has progressively reduced; it has been recognized that implantation at a very early age (12-18 months) provides children with the best outcomes, taking advantage of sensitive periods of auditory development. Bilateral implantation offers a better sound localization, as well as a superior ability to understand speech in noisy environments than unilateral cochlear implant. Deafened children with special clinical situations, including inner ear malformation, cochlear nerve deficiency, cochlear ossification, and additional disabilities can be successfully treated, even thogh they require an individualized candidacy evaluation and a complex post-implantation rehabilitation. Benefits from cochlear implantation include not only better abilities to hear and to develop speech and language skills, but also improved academic attainment, improved quality of life, and better employment status. Cochlear implants permit deaf people to hear, but they have a long way to go before

  2. Estimating total knee replacement joint load ratios from kinematics.

    Science.gov (United States)

    Fitzpatrick, Clare K; Rullkoetter, Paul J

    2014-09-22

    Accurate prediction of loads acting at the joint in total knee replacement (TKR) patients is key to developing experimental or computational simulations which evaluate implant designs under physiological loading conditions. In vivo joint loads have been measured for a small number of telemetric TKR patients, but in order to assess device performance across the entire patient population, a larger patient cohort is necessary. This study investigates the accuracy of predicting joint loads from joint kinematics. Specifically, the objective of the study was to assess the accuracy of internal-external (I-E) and anterior-posterior (A-P) joint load predictions from I-E and A-P motions under a given compressive load, and to evaluate the repeatability of joint load ratios (I-E torque to compressive force (I-E:C), and A-P force to compressive force (A-P:C)) for a range of compressive loading profiles. A tibiofemoral finite element model was developed and used to simulate deep knee bend, chair-rise and step-up activities for five patients. Root-mean-square (RMS) differences in I-E:C and A-P:C load ratios between telemetric measurements and model predictions were less than 1.10e-3 Nm/N and 0.035 N/N for all activities. I-E:C and A-P:C load ratios were consistently reproduced regardless of the compressive force profile applied (RMS differences less than 0.53e-3 Nm/N and 0.010 N/N, respectively). When error in kinematic measurement was introduced to the model, joint load predictions were forgiving to kinematic measurement error when conformity between femoral and tibial components was low. The prevalence of kinematic data, in conjunction with the analysis presented here, facilitates determining the scope of A-P and I-E joint loading ratios experienced by the TKR population.

  3. An introduction to single implant abutments.

    LENUS (Irish Health Repository)

    Warreth, Abdulhadi

    2013-01-01

    This article is an introduction to single implant abutments and aims to provide basic information about abutments which are essential for all dental personnel who are involved in dental implantology. Clinical Relevance: This article provides a basic knowledge of implants and implant abutments which are of paramount importance, as replacement of missing teeth with oral implants has become a well-established clinical procedure.

  4. 21 CFR 522.1350 - Melatonin implant.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Melatonin implant. 522.1350 Section 522.1350 Food... Melatonin implant. (a) Specifications. The drug is a silicone rubber elastomer implant containing 2.7...—(1) Amount. One implant per mink. (2) Indications for use. For use in healthy male and female kit...

  5. Accidental Implant Screwdriver Ingestion: A Rare Complication during Implant Placement.

    OpenAIRE

    Anshul Jain; Baliga, Shridhar D

    2014-01-01

    One of the complications during a routine dental implant placement is accidental ingestion of the implant instruments, which can happen when proper precautions are not taken. Appropriate radiographs should be taken to locate the correct position of foreign body; usually the foreign body passes asymptomatically from gastrointestinal tract but sometimes it may lead to intestinal obstruction, perforations and impactions. The aim of this article is to report accidental ingestion of 19 mm long scr...

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

    DEFF Research Database (Denmark)

    Babiker, Hassan

    2013-01-01

    Bone graft is widely used within orthopaedic surgery especially in revision joint arthroplasty and spine fusion. The early implant fixation in the revision situation of loose joint prostheses is important for the long-term survival. Bone autograft has been considered as gold standard in many...... orthopaedic procedures, whereas allograft is the gold standard by replacement of extensive bone loss. However, the use of autograft is associated with donor site morbidity, especially chronic pain. In addition, the limited supply is a significant clinical challenge. Limitations in the use of allograft include...... skeletal bones. The osteoconductive properties of the composite might be improved by adding bone marrow aspirate (BMA), which can be harvested during surgery. Other alternatives to bone graft are demineralised bone matrix (DBM) and human cancellous bone (CB). DBM is prepared by acid extraction of human...

  7. Nanometric Finishing on Biomedical Implants by Abrasive Flow Finishing

    Science.gov (United States)

    Subramanian, Kavithaa Thirumalai; Balashanmugam, Natchimuthu; Shashi Kumar, Panaghra Veeraiah

    2016-01-01

    Abrasive flow finishing (AFF) is a non-conventional finishing technique that offers better accuracy, efficiency, consistency, economy in finishing of complex/difficult to machine materials/components and provides the possibility of effective automation as aspired by the manufacturing sector. The present study describes the finishing of a hip joint made of ASTM grade Co-Cr alloy by Abrasive Flow Machining (AFM) process. The major input parameters of the AFF process were optimized for achieving nanometric finishing of the component. The roughness average (Ra) values were recorded during experimentation using surface roughness tester and the results are discussed in detail. The surface finished hip joints were characterized using Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and residual stress analysis using X-Ray Diffraction (XRD). The discussion lays emphasis on the significance, efficacy and versatile nature of the AFF process in finishing of bio-medical implants.

  8. Fabrication and evaluation of SixNy coatings for total joint replacements.

    Science.gov (United States)

    Olofsson, J; Pettersson, M; Teuscher, N; Heilmann, A; Larsson, K; Grandfield, K; Persson, C; Jacobson, S; Engqvist, H

    2012-08-01

    Wear particles from the bearing surfaces of joint implants are one of the main limiting factors for total implant longevity. Si(3)N(4) is a potential wear resistant alternative for total joint replacements. In this study, Si(x)N(y)-coatings were deposited on cobalt chromium-discs and Si-wafers by a physical vapour deposition process. The tribological properties, as well as surface appearance, chemical composition, phase composition, structure and hardness of these coatings were analysed. The coatings were found to be amorphous or nanocrystalline, with a hardness and coefficient of friction against Si(3)N(4) similar to that found for bulk Si(3)N(4). The low wear rate of the coatings indicates that they have a potential as bearing surfaces of joint replacements. The adhesion to the substrates remains to be improved.

  9. A symptomatic coracoclavicular joint

    NARCIS (Netherlands)

    Cheung, T.F.S.; Boerboom, A.L.; Wolf, R.F.E.; Diercks, Ron

    2006-01-01

    Bilateral coracoclavicular joints were found in a 44-year-old male patient following a fall. He had an Indonesian mother and a Dutch father. Prior to the injury he was asymptomatic and had full range of movement in both shoulders but the trauma resulted in pain and limitation of movement in the left

  10. Joint Custody and Coparenting.

    Science.gov (United States)

    Sell, Kenneth D.

    Results are presented of an intensive search of U.S. newspapers and periodicals on the joint custody of children after divorce, where both parents have continued responsibility for parenting and where the children spend part of each week, month, or year with both of the parents. Areas of concern addressed by these materials include the following:…

  11. Untreated silicone breast implant rupture

    DEFF Research Database (Denmark)

    Hölmich, Lisbet R; Vejborg, Ilse M; Conrad, Carsten;

    2004-01-01

    Implant rupture is a well-known complication of breast implant surgery that can pass unnoticed by both patient and physician. To date, no prospective study has addressed the possible health implications of silicone breast implant rupture. The aim of the present study was to evaluate whether...... untreated ruptures are associated with changes over time in magnetic resonance imaging findings, serologic markers, or self-reported breast symptoms. A baseline magnetic resonance imaging examination was performed in 1999 on 271 women who were randomly chosen from a larger cohort of women having cosmetic...... breast implants for a median period of 12 years (range, 3 to 25 years). A follow-up magnetic resonance imaging examination was carried out in 2001, excluding women who underwent explantation in the period between the two magnetic resonance imaging examinations (n = 44). On the basis of these examinations...

  12. Peri-implant esthetics assessment and management

    OpenAIRE

    Aarthi S Balasubramaniam; Raja, Sunitha V.; Libby John Thomas

    2013-01-01

    Providing an esthetic restoration in the anterior region of the mouth has been the basis of peri-implant esthetics. To achieve optimal esthetics, in implant supported restorations, various patient and tooth related factors have to be taken into consideration. Peri-implant plastic surgery has been adopted to improve the soft tissue and hard tissue profiles, during and after implant placement. The various factors and the procedures related to enhancement of peri-implant esthetics have been disc...

  13. Computerized implant-dentistry: Advances toward automation

    OpenAIRE

    Minkle Gulati; Vishal Anand; Sanjeev Kumar Salaria; Nikil Jain; Shilpi Gupta

    2015-01-01

    Advancements in the field of implantology such as three-dimensional imaging, implant-planning software, computer-aided-design/computer-aided-manufacturing (CAD/CAM) technology, computer-guided, and navigated implant surgery have led to the computerization of implant-dentistry. This three-dimensional computer-generated implant-planning and surgery has not only enabled accurate preoperative evaluation of the anatomic limitations but has also facilitated preoperative planning of implant position...

  14. Cochlear Implants and Brain Plasticity

    OpenAIRE

    Fallon, James B.; Irvine, Dexter R. F.; Shepherd, Robert K.

    2002-01-01

    Cochlear implants have been implanted in over 110,000 deaf adults and children worldwide and provide these patients with important auditory cues necessary for auditory awareness and speech perception via electrical stimulation of the auditory nerve (AN). In 1942 Woolsey & Walzl presented the first report of cortical responses to localised electrical stimulation of different sectors of the AN in normal hearing cats, and established the cochleotopic organization of the projections to primary au...

  15. Carbon coatings for medical implants

    OpenAIRE

    K. Bakowicz-Mitura; P. Couvrat; I. Kotela; P. Louda; D. Batory; J. Grabarczyk

    2007-01-01

    Purpose: In this paper we report in vitro and in vivo results of Nanocrystalline Diamond Coatings whichare used in medicine onto medical implants The very important property of carbon coatings is the protectionliving organism against the metalosis. Different medical implants with complicated shapes are covering byNanocrystalline Diamond Coatings by RF dense plasma CVD.Design/methodology/approach: 1) Material characterizations of deposited coatings have been evaluated by using:Transmission Ele...

  16. Implant rehabilitation in bruxism patient

    OpenAIRE

    GOIATO, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-01-01

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocol...

  17. The vestibular implant: Quo vadis?

    Directory of Open Access Journals (Sweden)

    Raymond eVan De Berg

    2011-08-01

    Full Text Available AbstractObjective: to assess the progress of the development of the vestibular implant and its feasibility short-term. Data sources: a search was performed in Pubmed, Medline and Embase. Key words used were vestibular prosth* and vestibular implant. The only search limit was language: English or Dutch. Additional sources were medical books, conference lectures and our personal experience with per-operative vestibular stimulation in patients selected for cochlear implantation.Study selection: all studies about the vestibular implant and related topics were included and evaluated by two reviewers. No study was excluded since every study investigated different aspects of the vestibular implant. Data extraction and synthesis: data was extracted by the first author from selected reports, supplemented by additional information, medical books conference lectures. Since each study had its own point of interest with its own outcomes, it was not possible to compare data of different studies. Conclusion: to use a basic vestibular implant in humans seems feasible in the very near future. Investigations show that electric stimulation of the canal nerves induces a nystagmus which corresponds to the plane of the canal which is innervated by the stimulated nerve branch. The brain is able to adapt to a higher baseline stimulation, while still reacting on a dynamic component. The best response will be achieved by a combination of the optimal stimulus (stimulus profile, stimulus location, precompensation, complemented by central vestibular adaptation. The degree of response will probably vary between individuals, depending on pathology and their ability to adapt.

  18. Ion implanted dielectric elastomer circuits

    Science.gov (United States)

    O'Brien, Benjamin M.; Rosset, Samuel; Anderson, Iain A.; Shea, Herbert R.

    2013-06-01

    Starfish and octopuses control their infinite degree-of-freedom arms with panache—capabilities typical of nature where the distribution of reflex-like intelligence throughout soft muscular networks greatly outperforms anything hard, heavy, and man-made. Dielectric elastomer actuators show great promise for soft artificial muscle networks. One way to make them smart is with piezo-resistive Dielectric Elastomer Switches (DES) that can be combined with artificial muscles to create arbitrary digital logic circuits. Unfortunately there are currently no reliable materials or fabrication process. Thus devices typically fail within a few thousand cycles. As a first step in the search for better materials we present a preliminary exploration of piezo-resistors made with filtered cathodic vacuum arc metal ion implantation. DES were formed on polydimethylsiloxane silicone membranes out of ion implanted gold nano-clusters. We propose that there are four distinct regimes (high dose, above percolation, on percolation, low dose) in which gold ion implanted piezo-resistors can operate and present experimental results on implanted piezo-resistors switching high voltages as well as a simple artificial muscle inverter. While gold ion implanted DES are limited by high hysteresis and low sensitivity, they already show promise for a range of applications including hysteretic oscillators and soft generators. With improvements to implanter process control the promise of artificial muscle circuitry for soft smart actuator networks could become a reality.

  19. Nanostructured Surfaces of Dental Implants

    Directory of Open Access Journals (Sweden)

    Stefano Sivolella

    2013-01-01

    Full Text Available The structural and functional fusion of the surface of the dental implant with the surrounding bone (osseointegration is crucial for the short and long term outcome of the device. In recent years, the enhancement of bone formation at the bone-implant interface has been achieved through the modulation of osteoblasts adhesion and spreading, induced by structural modifications of the implant surface, particularly at the nanoscale level. In this context, traditional chemical and physical processes find new applications to achieve the best dental implant technology. This review provides an overview of the most common manufacture techniques and the related cells-surface interactions and modulation. A Medline and a hand search were conducted to identify studies concerning nanostructuration of implant surface and their related biological interaction. In this paper, we stressed the importance of the modifications on dental implant surfaces at the nanometric level. Nowadays, there is still little evidence of the long-term benefits of nanofeatures, as the promising results achieved in vitro and in animals have still to be confirmed in humans. However, the increasing interest in nanotechnology is undoubted and more research is going to be published in the coming years.

  20. Development and application of biomimetic electrospun nanofibers in total joint replacement

    Science.gov (United States)

    Song, Wei

    Failure of osseointegration (direct anchorage of an implant by bone formation at the bone-implant surface) and implant infection (such as that caused by Staphylococcus aureus, S. aureus) are the two main causes of implant failure and loosening. There is a critical need for orthopedic implants that promote rapid osseointegration and prevent bacterial colonization, particularly when placed in bone compromised by disease or physiology of the patients. A better understanding of the key factors that influence cell fate decisions at the bone-implant interface is required. Our study is to develop a class of "bone-like" nanofibers (NFs) that promote osseointegration while preventing bacterial colonization and subsequent infections. This research goal is supported by our preliminary data on the preparation of coaxial electrospun NFs composed of polycaprolactone (PCL) and polyvinyl alcohol (PVA) polymers arranged in a core-sheath shape. The PCL/PVA NFs are biocompatible and biodegradable with appropriate fiber diameter, pore size and mechanical strength, leading to enhanced cell adhesion, proliferation and differentiation of osteoblast precursor cells. The objective is to develop functionalized "bone-like" PCL/PVA NFs matrix embedded with antibiotics (doxycycline (Doxy), bactericidal and anti-osteoclastic) on prosthesis surface. Through a rat tibia implantation model, the Doxy incorporated coaxial NFs has demonstrated excellent in promoting osseointegration and bacteria inhibitory efficacy. NFs coatings significantly enhanced the bonding between implant and bone remodeling within 8 weeks. The SA-induced osteomyelitis was prevented by the sustained release of Doxy from NFs. The capability of embedding numerous bio-components including proteins, growth factors, drugs, etc. enables NFs an effective solution to overcome the current challenged issue in Total joint replacement. In summary, we proposed PCL/PVA electrospun nanofibers as promising biomaterials that can be applied on

  1. Characterization of cell cultures in contact with different orthopedic implants biomaterials

    Science.gov (United States)

    Ouenzerfi, G.; Hannoun, A.; Hassler, M.; Brizuela, L.; Youjil, S.; Bougault, C.; Trunfio-Sfarghiu, A.-M.

    2016-08-01

    The aim of this study is to identify the role of biological and mechanical constraints (at the cellular level) surrounding living tissues (cartilage and bone) in the presence of different joint implant biomaterials. In this fact, cells cultures in the presence of different types of biomaterials (pyrolytic carbon, cobalt-Chromium, titanium) has been performed. These cell cultures were subjected to biological characterization tests and mechanical characterization. The obtained results correlate with the in vivo observations (a promotion of the creation of a neocartilagical tissue in contact with the Pyrolytic Carbon implants).

  2. Imaging of common breast implants and implant-related complications: A pictorial essay.

    Science.gov (United States)

    Shah, Amisha T; Jankharia, Bijal B

    2016-01-01

    The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  3. Imaging of common breast implants and implant-related complications: A pictorial essay

    Directory of Open Access Journals (Sweden)

    Amisha T Shah

    2016-01-01

    Full Text Available The number of women undergoing breast implant procedures is increasing exponentially. It is, therefore, imperative for a radiologist to be familiar with the normal and abnormal imaging appearances of common breast implants. Diagnostic imaging studies such as mammography, ultrasonography, and magnetic resonance imaging are used to evaluate implant integrity, detect abnormalities of the implant and its surrounding capsule, and detect breast conditions unrelated to implants. Magnetic resonance imaging of silicone breast implants, with its high sensitivity and specificity for detecting implant rupture, is the most reliable modality to asses implant integrity. Whichever imaging modality is used, the overall aim of imaging breast implants is to provide the pertinent information about implant integrity, detect implant failures, and to detect breast conditions unrelated to the implants, such as cancer.

  4. Strain induced in the condyle by self-tapping screws in the Biomet alloplastic temporomandibular joint: a preliminary experimental study.

    Science.gov (United States)

    Ramos, A; Duarte, R J; Mesnard, M

    2015-11-01

    The main aim of this study was to analyze how screws affect the strain concentration induced on the mandibular condyle during implantation, screwing, and drilling, as well as after condylar loading. A clean cadaveric mandible was analyzed experimentally in the intact state and was then implanted with a Biomet/Lorenz Microfixation temporomandibular joint (TMJ) implant with seven bicortical self-tapping screws. The external surface of the mandible was instrumented with three strain gauges. A load of 500N on the TMJ was applied to the condyle before and after implantation. The results showed a strain concentration of -1500μɛ near the screws due to their implantation on the external surface of the mandible. The drilling process induced up to 80μɛ near the hole. The strain concentration did not change when there were more than six screws. Loading on the TMJ before and after implantation presented only a 10% difference in maximum principal strain. This study demonstrates the importance of the strain concentration induced by the screws. The process of implanting screws shows the importance of lateral surface preparation for a good fit in the condyle. Strain distribution after implantation and loading of the Biomet implant was found to be similar to that in the intact condyle. PMID:26194773

  5. Shoulder Joint For Protective Suit

    Science.gov (United States)

    Kosmo, Joseph J.; Smallcombe, Richard D.

    1994-01-01

    Shoulder joint allows full range of natural motion: wearer senses little or no resisting force or torque. Developed for space suit, joint offers advantages in protective garments for underwater work, firefighting, or cleanup of hazardous materials.

  6. Joint Infection (Beyond the Basics)

    Science.gov (United States)

    ... for some deep joints (eg, hip, shoulder), surgical placement of a drainage tube. ARTIFICIAL JOINT INFECTION — People ... medications, the user is advised to check the product information sheet accompanying each drug to verify conditions ...

  7. Cochlear implantation: a biomechanical prosthesis for hearing loss.

    Science.gov (United States)

    Yawn, Robert; Hunter, Jacob B; Sweeney, Alex D; Bennett, Marc L

    2015-01-01

    Cochlear implants are a medical prosthesis used to treat sensorineural deafness, and one of the greatest advances in modern medicine. The following article is an overview of cochlear implant technology. The history of cochlear implantation and the development of modern implant technology will be discussed, as well as current surgical techniques. Research regarding expansion of candidacy, hearing preservation cochlear implantation, and implantation for unilateral deafness are described. Lastly, innovative technology is discussed, including the hybrid cochlear implant and the totally implantable cochlear implant.

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

    Directory of Open Access Journals (Sweden)

    Stefan Landgraeber

    2014-01-01

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

  9. Biocompatibility of Delrin 150: a creep-resistant polymer for total joint prostheses.

    Science.gov (United States)

    Fister, J S; Memoli, V A; Galante, J O; Rostoker, W; Urban, R M

    1985-01-01

    A thermoplastic polymer, Delrin 150 (polyoxymethylene homopolymer), with creep resistance ten times that of ultrahigh-molecular-weight polyethylene, is used as a material for total joint prostheses. A study was made of the local and systemic host response to this polymer when implanted in three different mammalian species. 316 LC stainless steel was used as a control. The materials were implanted into muscle and bone as solid cylinders. A total of 446 samples were implanted into 74 animals. The duration of implantation ranged from 2 weeks to 2 years. A semi-quantitative evaluation of local tissue reaction was performed. For each implant, 16 histological criteria were graded for severity of host tissue reaction. The liver, spleen, kidneys, pancreas, and lungs from each animal were also studied for evidence of systemic toxicity. The polymer implants exhibited a mild tissue reaction with the same characteristics as the control. Local tumor formation, bone osteolysis, and surrounding muscle necrosis were not seen. No pathological changes compatible with systemic toxicity by Delrin 150 were observed in the study of the organs. Delrin 150 in solid form did not exhibit local or systemic toxicity and is therefore biocompatible by this study. Powder implantation studies should be performed to simulate tissue response to wear particles. PMID:4066726

  10. Joint cumulants for natural independence

    OpenAIRE

    Hasebe, Takahiro; Saigo, Hayato

    2011-01-01

    Many kinds of independence have been defined in non-commutative probability theory. Natural independence is an important class of independence; this class consists of five independences (tensor, free, Boolean, monotone and anti-monotone ones). In the present paper, a unified treatment of joint cumulants is introduced for natural independence. The way we define joint cumulants enables us not only to find the monotone joint cumulants but also to give a new characterization of joint cumulants fo...

  11. Achieving joint benefits from joint implementation

    Energy Technology Data Exchange (ETDEWEB)

    Moomaw, W.R. [Tufts Univ., Medford, MA (United States)

    1995-11-01

    Joint Implementation (JI) appears to have been born with Applied Energy Services Guatemala project in 1988. That project, to plant 52 million trees, protect existing forests from cutting and fire, and enhance rural development, is being implemented by CARE Guatemala to offset 120 per cent of the emissions of a small coal burning power plant that has been built in Connecticut. Since that time, several utilities and governments have initiated additional projects. Not all of these necessarily consist of tree planting in other countries, but may consist of energy efficiency or energy conservation programs designed to reduce carbon emissions by at least as much as the additional releases from a new facility. All JI projects share the characteristic of linking the release of greenhouse gases in an industrial country with an offset that reduces or absorbs a comparable amount in another country. The emitter in the industrial country is willing to pay for the reduction elsewhere because costs are less than they would be at home.

  12. JOINT VENTURES AMONG EXPORTING FIRMS

    OpenAIRE

    CHAUDHURI, Prabal Ray

    2000-01-01

    In this paper we examine the incentive for joint venture formation among exporting firms. We show that an increase in domestic demand increases the incentive for joint venture formation. An increase in world price, however, can either increase or decrease the incentive for joint venture formation.

  13. Comparison of Implant Stability Before Prosthetic Loading of Two Dental Implant Systems

    OpenAIRE

    Lagdive, Sanjay Balaji; Lagdive, Sushma Sanjay

    2013-01-01

    Dental implantology is the state of the art technique to replace missing teeth. Implant stability of implant jeopardizes its longevity and success of treatment. This study evaluates the implant stability of implant before and after 4 months of the implant placement, but before prosthetically loading it. Ten two-stage implants of Life care and Nobel Biocare dental implants were placed in 20 patients. Digital OPG was taken on the day of implant placement. After 4 months, at the time of second s...

  14. Joint hypermobility syndrome pain.

    Science.gov (United States)

    Grahame, Rodney

    2009-12-01

    Joint hypermobility syndrome (JHS) was initially defined as the occurrence of musculoskeletal symptoms in the presence of joint laxity and hypermobility in otherwise healthy individuals. It is now perceived as a commonly overlooked, underdiagnosed, multifaceted, and multisystemic heritable disorder of connective tissue (HDCT), which shares many of the phenotypic features of other HDCTs such as Marfan syndrome and Ehlers-Danlos syndrome. Whereas the additional flexibility can confer benefits in terms of mobility and agility, adverse effects of tissue laxity and fragility can give rise to clinical consequences that resonate far beyond the confines of the musculoskeletal system. There is hardly a clinical specialty to be found that is not touched in one way or another by JHS. Over the past decade, it has become evident that of all the complications that may arise in JHS, chronic pain is arguably the most menacing and difficult to treat. PMID:19889283

  15. JET Joint Undertaking

    International Nuclear Information System (INIS)

    The paper presents the annual report of the Joint European Torus (JET) Joint Undertaking, 1986. The report is divided into two parts: a part on the scientific and technical programme of the project, and a part setting out the administration and organisation of the Project. The first part includes: a summary of the main features of the JET apparatus, the JET experimental programme, the position of the Project in the overall Euratom programme, and how JET relates to other large fusion devices throughout the world. In addition, the technical status of JET is described, as well as the results of the JET operations in 1986. The final section of the first part outlines the proposed future programme of JET. (U.K.)

  16. Laundry joint venture.

    Science.gov (United States)

    Giancola, D; Voyvodich, M

    1984-12-01

    Many hospitals are concerned about the loss of control which is associated with contracting for linen service. On the the hand, many laundries do not have the resources or experience to serve hospitals in a comprehensive and trouble-free manner. In many communities a joint venture, such as the one described here, can successfully combine the interests of the hospital and laundry communities without causing the hospitals to lose control of the service and without requiring the laundry operator to have detailed knowledge of hospital operations. As more hospitals opt for contract service, and if this service is to be provided at the lowest total cost, the hospitals and the laundries must come to grips with the problems surrounding the laundry-hospital interface. A joint venture, such as that described here, is one way to accomplish this.

  17. Joint International Accelerator School

    CERN Multimedia

    CERN Accelerator School

    2014-01-01

    The CERN and US Particle Accelerator Schools recently organised a Joint International Accelerator School on Beam Loss and Accelerator Protection, held at the Hyatt Regency Hotel, Newport Beach, California, USA from 5-14 November 2014. This Joint School was the 13th in a series of such schools, which started in 1985 and also involves the accelerator communities in Japan and Russia.   Photo courtesy of Alfonse Pham, Michigan State University.   The school attracted 58 participants representing 22 different nationalities, with around half from Europe and the other half from Asia and the Americas. The programme comprised 26 lectures, each of 90 minutes, and 13 hours of case study. The students were given homework each day and had an opportunity to sit a final exam, which counted towards university credit. Feedback from the participants was extremely positive, praising the expertise and enthusiasm of the lecturers, as well as the high standard and quality of their lectures. Initial dis...

  18. Materials for endosseous dental implants.

    Science.gov (United States)

    Wataha, J C

    1996-02-01

    The goal of placement of endosseous dental implants is to achieve osseointegration or biointegration of the bone with the implant. A wide variety of materials has been used for these implants, but only a few promote osseointegration and biointegration. Titanium and titanium alloy (Ti6A14V) have been the most widely used of these materials. The surface oxide of titanium appears to be central to the ability of this material to osseointegrate. The oxide limits dissolution of elements and promotes the deposition of biological molecules which allow bone to exist as close as 30 A to the surface of the implant. The details of the ultrastructure of the gap between the implant and bone remain undefined, and the consequences of elements which are released on the interface over time are not known. These areas of investigation are particularly important in defining the differences between commercially pure titanium implants and those made of titanium, aluminium and vanadium. The epithelial interface between the gingiva and titanium appears to contain many of the structural characteristics of the native tooth-gingiva interface, but details are still vague. The connective tissue interface with the titanium appears to be one of tightly fitting tissues rather than adhesion. Ceramic coatings appear to improve the ingrowth of bone and promote chemical integration of the implant with the bone. The characteristics of these coatings are complex and affect the bony response, but the mechanisms remain obscure. The degradation of the coatings is an issue of particular controversy. Progress in dental implantology is likely to continue as the interface between the material and bone is more clearly understood, and biological molecules and artificial tissues are developed.

  19. Long-Term Symptoms Onset and Heterotopic Bone Formation around a Total Temporomandibular Joint Prosthesis: a Case Report

    OpenAIRE

    Luca Guarda-Nardini; Daniele Manfredini; Marco Olivo; Giuseppe Ferronato

    2014-01-01

    Background: The literature on total alloplastic temporomandibular joint (TMJ) reconstructions is encouraging, and studies on total alloplastic TMJ replacements outcomes showed acceptable improvements in terms of both pain levels and jaw function. Nevertheless, some adverse events, such as heterotopic bone formation around the implanted prosthesis, may occur. In consideration of that, the present manuscript describes a case of heterotopic bone formation around a total temporomandibular joint p...

  20. Posttraumatic Temporomandibular Joint Disorders

    OpenAIRE

    Giannakopoulos, Helen E.; Quinn, Peter D.; Granquist, Eric; Chou, Joli C.

    2009-01-01

    The temporomandibular joint (TMJ) has many essential functions. None of its components are exempt from injury. Facial asymmetry, malocclusion, disturbances in growth, osteoarthritis, and ankylosis can manifest as complications from trauma to the TMJ. The goals of initial treatment include achievement of pretraumatic function, restoration of facial symmetry, and resolution of pain. These same objectives hold true for late repairs and reconstruction of the TMJ apparatus. Treatment is demanding,...

  1. The Joint Cities

    Directory of Open Access Journals (Sweden)

    Romano Fistola

    2010-04-01

    Full Text Available The new connections, which high speed train allows to activate among the metropolitan systems, seem to be able to give life to new urban macro-structures for which the transfer time, among the main poles of the railway segment, becomes comparable to an inside moving into the city and therefore considered as an inter-functional mobility. The tunnel effect generated by the high speed connection seems to be able to allow a new temporal and functional joint among the metropolitan systems consequently supporting the possibility, for the users, to move themselves among the different urban functions belonging to the different cities. The birth of these urban aggregations seems to drive towards new megalopolis, which we can define for the first time with the term: joint-city. For this new metropolitan settlement it seems to be very interesting to investigate the constitutive peculiarities, the systemic articulation, its relational structures, the evolutionary scenarios, and so on. The urban functions (activities can be considered as structures of relationships between people that allows to define "organizational links" inside the community; the urban functions are located in specific places inside urban container or in open spaces. The urban functions represent the urban engines and the functional system can be thought as the “soul of the city", abstract but essential to its survival. In the definition set out here the analysis is carried out for many interconnected urban functional system points (specifically those in Rome and Naples. The new high speed railway has to be considered not only as a new channel of mobility between cities, but as a real possibility of joint between the functional systems of the two centres. A final consideration can be carried out in relation to the possibility of implementing new measures of governance of urban transformations considering the new macro-city: the "Joint City".

  2. Jet Joint Undertaking

    International Nuclear Information System (INIS)

    The paper presents the Jet Joint Undertaking annual report 1987. A description is given of the JET and Euratom and International Fusion Programmes. The technical status of JET is outlined, including the development and improvements made to the system in 1987. The results of JET Operation in 1987 are described within the areas of: density effects, temperature improvements, energy confinement studies and other material effects. The contents also contain a summary of the future programme of JET. (U.K.)

  3. Biomimetic implant coatings.

    Science.gov (United States)

    Eisenbarth, E; Velten, D; Breme, J

    2007-02-01

    Biomaterials and tissue engineering technologies are becoming increasingly important in biomedical practice, particularly as the population ages. Cellular responses depend on topographical properties of the biomaterial at the nanometer scale. Structures on biomaterial surfaces are used as powerful tools to influence or even control interactions between implants and the biological system [; ]. The influence of nanometer sized surface structures on osteoblastlike cell interactions was tested with niobium oxide coatings on polished titanium slices (cp-Ti grade 2). The aim of the study was to investigate the influence of nanoscopic surface structures on osteoblast interactions in order to support collagen I production and cell adhesion. The coatings were done by means of the sol-gel process. The surface structure was adjusted by annealing of the metaloxide ceramic coatings due to temperature depended crystal growth. The applied annealing temperatures were 450, 550 and 700 degrees C for 1 h, corresponding to Ra-numbers of 7, 15 and 40 nm. The surfaces were characterized by means of AFM, DTA/TG, diffractometry and white light interferometry. The cell reactions were investigated concerning adhesion kinetics, migration, spreading, cell adhesion, and collagen I synthesis. The smooth surface (Ra=7 nm) resulted in the fastest cell anchorage and cell migration. The closest cell adhesion was reached with the surface structure of Ra=15 nm. The roughest surface (Ra=40 nm) impedes the cell migration as well as a proper spreading of the cells. The best results concerning cell adhesion and spreading was reached with an intermediate surface roughness of Ra=15 nm of the niobium oxide coating on cp-titanium slices. PMID:16828342

  4. Multicomponent Implant Releasing Dexamethasone

    Science.gov (United States)

    Nikkola, L.; Vapalahti, K.; Ashammakhi, N.

    2008-02-01

    Several inflammatory conditions are usually treated with corticosteroids. There are various problems like side effects with traditional applications of steroids, e.g. topical, or systemic routes. Local drug delivery systems have been studied and developed to gain more efficient administration with fewer side effects. Earlier, we reported on developing Dexamethasone (DX) releasing biodegradable fibers. However, their drug release properties were not satisfactory in terms of onset of drug release. Thus, we assessed the development of multicomponent (MC) implant to enhance earlier drug release from such biodegradable fibers. Poly (lactide-co-glycolide) (PLGA) and 2 wt-% and 8 wt-% DX were compounded and extruded with twin-screw extruder to form of fibers. Some of the fibers were sterilized to obtain a change in drug release properties. Four different fiber classes were studied: 2 wt-%, 8 wt-%, sterilized 2 wt-%, and sterilized 8 wt-%. 3×4 different DX-releasing fibers were then heat-pressed to form one multicomponent rod. Half of the rods where sterilized. Drug release was measured from initial fibers and multicomponent rods using a UV/VIS spectrometer. Shear strength and changes in viscosity were also measured. Drug release studies showed that drug release commenced earlier from multicomponent rods than from component fibers. Drug release from multicomponent rods lasted from day 30 to day 70. The release period of sterilized rods extended from day 23 to day 57. When compared to the original component fibers, the drug release from MC rods commenced earlier. The initial shear strength of MC rods was 135 MPa and decreased to 105 MPa during four weeks of immersion in phosphate buffer solution. Accordingly, heat pressing has a positive effect on drug release. After four weeks in hydrolysis, no disintegration was observed.

  5. Shoulder joint tuberculosis

    International Nuclear Information System (INIS)

    Despite the fact that joint tuberculosis is one of the most common forms of extrapulmonary tuberculosis, it is a disease entity that is very rare in Poland (less than 100 cases a year in the last 10 years). The symptoms are non-specific, and thus the disease is rarely taken into account in preliminary differential diagnosis. A 68-year-old female patient was admitted to the Internal Diseases Clinic due to oedema and pain of the right shoulder joint. The pain has been increasing for about 8 months. Physical examination revealed increased circumference and elevated temperature of the right shoulder joint. Limb function was retained. The full range of radiological and laboratory diagnostic examinations was performed, including the biopsy of the affected tissue which revealed the presence of Mycobacterium tuberculosis in the bacterial culture. Clinical improvement was obtained after introduction of TB drugs. Radiological diagnostic methods (X-ray, CT scans, MRI scans) provide high precision monitoring of articular lesions. However, the decisive diagnosis requires additional laboratory tests as well as histopathological and bacteriological assays

  6. The neuropathic joint.

    Science.gov (United States)

    Sequeira, W

    1994-01-01

    Neuropathic arthritis is a destructive arthropathy frequently associated with loss of proprioception. A third of patients, however, may have no demonstrable neurological deficit. Patients with diabetes, syphilis, syringomyelia and other neuropathies are particularly prone to developing this joint disease. The diagnosis of Charcot's joints should be considered in anyone who develops what appears to be a severe osteoarthritis or a transverse fracture of the tibia or fibula after minor trauma. Scoliosis with particularly destructive changes on radiography should prompt a search for syringomyelia or syphilis. The most common radiographic abnormalities are those of distension in 3D (Dislocation, Destruction and Degeneration). An atrophic form with resorption of the proximal humerus, most frequently described in syringomyelia, has been observed in diabetes. Loss of the distal end of the clavicle has not been described before in the neuropathies. These changes coupled with speckled calcification or shards of bone in the periarticular soft tissue confirm the diagnosis. Infection and CPPD crystal disease can be difficult to exclude. The joint fluid may be inflammatory and infection may be a complication. Treatment includes anti-inflammatories and splinting. Indications for surgery are limited. PMID:8070170

  7. Formation of tough composite joints

    Energy Technology Data Exchange (ETDEWEB)

    Brun, M.K. [GE Corporate Research and Development, Schenectady, NY (United States)

    1997-05-01

    Joints which exhibit tough fracture behavior were formed in a composite with a Si/SiC matrix reinforced with Textron SCS-6 fibers with either boron nitride or silicon nitride fiber coatings. In composites with BN coatings fibers were aligned uniaxially, while composites with Si{sub 3}N{sub 4}-coated fibers had a 0/90{degree} architecture. Lapped joints (joints with overlapping fingers) were necessary to obtain tough behavior. Geometrical requirements necessary to avoid brittle joint failure have been proposed. Joints with a simple overlap geometry (only a few fingers) would have to be very long in order to prevent brittle failure. Typical failure in these joints is caused by a crack propagating along the interfaces between the joint fingers. Joints of the same overall length, but with geometry changed to be symmetric about the joint centerline and with an extra shear surface exhibited tough fractures accompanied with extensive fiber pullout. The initial matrix cracking of these joints was relatively low because cracks propagated easily through the ends of the fingers. Joints with an optimized stepped sawtooth geometry produced composite-like failures with the stress/strain curves containing an elastic region followed by a region of rising stress with an increase of strain. Increasing the fiber/matrix interfacial strength from 9 to 25 MPa, by changing the fiber coating, increased matrix cracking and ultimate strength of the composite significantly. The best joints had matrix cracking stress and ultimate strength of 138 and 240 MPa, respectively. Joint failure was preceded by multiple matrix cracking in the entire composite. The high strength of the joints will permit building of structures containing joints with only a minor reduction of design stresses.

  8. Falha prematura em implantes orais = Early oral implant failures

    Directory of Open Access Journals (Sweden)

    Fadanelli, Alexandro Bianchi

    2005-01-01

    Full Text Available Atualmente, ainda há uma percentagem significativa de fracassos de implantes na prática clínica, causando transtorno para o profissional e para o paciente. O objetivo deste estudo foi avaliar a bibliografia disponível sobre o assunto, apresentar um caso clínico e discutir os aspectos relacionados aos insucessos na terapia com implantes ocorridos durante o período de osteointegração. A avaliação da literatura mostrou haverem múltiplos fatores possivelmente envolvidos nas falhas de implantes, sendo que através do estudo das falhas pode-se minimizar sua ocorrência

  9. Medical implants and methods of making medical implants

    Science.gov (United States)

    Shaw, Wendy J; Yonker, Clement R; Fulton, John L; Tarasevich, Barbara J; McClain, James B; Taylor, Doug

    2014-09-16

    A medical implant device having a substrate with an oxidized surface and a silane derivative coating covalently bonded to the oxidized surface. A bioactive agent is covalently bonded to the silane derivative coating. An implantable stent device including a stent core having an oxidized surface with a layer of silane derivative covalently bonded thereto. A spacer layer comprising polyethylene glycol (PEG) is covalently bonded to the layer of silane derivative and a protein is covalently bonded to the PEG. A method of making a medical implant device including providing a substrate having a surface, oxidizing the surface and reacting with derivitized silane to form a silane coating covalently bonded to the surface. A bioactive agent is then covalently bonded to the silane coating. In particular instances, an additional coating of bio-absorbable polymer and/or pharmaceutical agent is deposited over the bioactive agent.

  10. Implant-supported overdenture with prefabricated bar attachment system in mandibular edentulous patient

    Science.gov (United States)

    Ha, Seung-Ryong; Song, Seung-Il; Hong, Seong-Tae; Kim, Gy-Young

    2012-01-01

    Implant-supported overdenture is a reliable treatment option for the patients with edentulous mandible when they have difficulty in using complete dentures. Several options have been used for implant-supported overdenture attachments. Among these, bar attachment system has greater retention and better maintainability than others. SFI-Bar® is prefabricated and can be adjustable at chairside. Therefore, laboratory procedures such as soldering and welding are unnecessary, which leads to fewer errors and lower costs. A 67-year-old female patient presented, complaining of mobility of lower anterior teeth with old denture. She had been wearing complete denture in the maxilla and removable partial denture in the mandible with severe bone loss. After extracting the teeth, two implants were placed in front of mental foramen, and SFI-Bar® was connected. A tube bar was seated to two adapters through large ball joints and fixation screws, connecting each implant. The length of the tube bar was adjusted according to inter-implant distance. Then, a female part was attached to the bar beneath the new denture. This clinical report describes two-implant-supported overdenture using the SFI-Bar® system in a mandibular edentulous patient. PMID:23236580

  11. Is a radiolucent breast implant needed

    International Nuclear Information System (INIS)

    Over 1 million American women have undergone augmentation mammoplasty. The silicone implants used create numerous technical difficulties during mammography. An American College of Radiology mammography phantom was used to assess the effect prototype implants have on resolution of microcalcifications and masses. Implants filled with silicone gel and/or saline had equal radiodensity and obscured all phantom artifacts. Implants filled with peanut oil and sunflower oil had equal radiolucency and allowed visualization of microcalcifications and several masses. The implant filled with gelatin was of intermediate radiodensity. A more radiolucent breast implant is possible, and further research is needed to define the best filter material and test its biocompatibility

  12. Implantable biomedical devices on bioresorbable substrates

    Science.gov (United States)

    Rogers, John A; Kim, Dae-Hyeong; Omenetto, Fiorenzo; Kaplan, David L; Litt, Brian; Viventi, Jonathan; Huang, Yonggang; Amsden, Jason

    2014-03-04

    Provided herein are implantable biomedical devices, methods of administering implantable biomedical devices, methods of making implantable biomedical devices, and methods of using implantable biomedical devices to actuate a target tissue or sense a parameter associated with the target tissue in a biological environment. Each implantable biomedical device comprises a bioresorbable substrate, an electronic device having a plurality of inorganic semiconductor components supported by the bioresorbable substrate, and a barrier layer encapsulating at least a portion of the inorganic semiconductor components. Upon contact with a biological environment the bioresorbable substrate is at least partially resorbed, thereby establishing conformal contact between the implantable biomedical device and the target tissue in the biological environment.

  13. Capacitive Feedthroughs for Medical Implants

    Science.gov (United States)

    Grob, Sven; Tass, Peter A.; Hauptmann, Christian

    2016-01-01

    Important technological advances in the last decades paved the road to a great success story for electrically stimulating medical implants, including cochlear implants or implants for deep brain stimulation. However, there are still many challenges in reducing side effects and improving functionality and comfort for the patient. Two of the main challenges are the wish for smaller implants on one hand, and the demand for more stimulation channels on the other hand. But these two aims lead to a conflict of interests. This paper presents a novel design for an electrical feedthrough, the so called capacitive feedthrough, which allows both reducing the size, and increasing the number of included channels. Capacitive feedthroughs combine the functionality of a coupling capacitor and an electrical feedthrough within one and the same structure. The paper also discusses the progress and the challenges of the first produced demonstrators. The concept bears a high potential in improving current feedthrough technology, and could be applied on all kinds of electrical medical implants, even if its implementation might be challenging.

  14. Laboratory characterization of rock joints

    International Nuclear Information System (INIS)

    A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed

  15. Laboratory characterization of rock joints

    Energy Technology Data Exchange (ETDEWEB)

    Hsiung, S.M.; Kana, D.D.; Ahola, M.P.; Chowdhury, A.H.; Ghosh, A. [Southwest Research Inst., San Antonio, TX (United States). Center for Nuclear Waste Regulatory Analyses

    1994-05-01

    A laboratory characterization of the Apache Leap tuff joints under cyclic pseudostatic and dynamic loads has been undertaken to obtain a better understanding of dynamic joint shear behavior and to generate a complete data set that can be used for validation of existing rock-joint models. Study has indicated that available methods for determining joint roughness coefficient (JRC) significantly underestimate the roughness coefficient of the Apache Leap tuff joints, that will lead to an underestimation of the joint shear strength. The results of the direct shear tests have indicated that both under cyclic pseudostatic and dynamic loadings the joint resistance upon reverse shearing is smaller than that of forward shearing and the joint dilation resulting from forward shearing recovers during reverse shearing. Within the range of variation of shearing velocity used in these tests, the shearing velocity effect on rock-joint behavior seems to be minor, and no noticeable effect on the peak joint shear strength and the joint shear strength for the reverse shearing is observed.

  16. Patient-adapted treatment for prosthetic hip joint infection.

    Science.gov (United States)

    Baker, Richard P; Furustrand Tafin, Ulrika; Borens, Olivier

    2015-01-01

    Hip joint replacement is 1 of the most successful surgical procedures of the last century and the number of replacements implanted is steadily growing. An infected hip arthroplasty is a disaster, it leads to patient suffering, surgeon's frustration and significant costs to the health system. The treatment of an infected hip replacement is challenging, healing rates can be low, functional results poor with decreased patient satisfaction. However, if a patient-adapted treatment of infected hip joints is used a success rate of above 90% can be obtained.Patient-adapted treatment is based on 5 important concepts: teamwork; understanding the biofilm; diagnostic accuracy; correct definition and classification of PJI; and patient-tailored treatment.This review presents a patient-adapted treatment strategy to prosthetic hip infection. It incorporates the best aspects of the single and staged surgical strategies and promotes the short interval philosophy for the 2-stage approach. PMID:26044528

  17. Surgical Complications of Cochlear Implantation

    Directory of Open Access Journals (Sweden)

    Basir Hashemi

    2010-03-01

    Full Text Available Cochlear implantation is a method used for the treatment ofpatients with profound hearing loss. This procedure may theaccompanied by some major or minor complications. Weevaluated the surgical complications of cochlear implantationin Fars province (south of Iran. A total of 150 patients withcochlear implantation were enrolled in the present study. Mostof the patients were pre-lingual children and most of our deviceswere nucleus prosthesis. We had three device failuresand four major complications, including one misplaced electrode,one case of meningitis, one case of foreign body reactionto suture and one case with extensive hematoma. Thesecomplications were managed successfully by surgical interventionor re-implantation. Facial nerve damage or woundbreakdown was not seen. Minor complications including smallhematoma, edema, stitch infection and dizziness were found in15 cases, which were managed medically. In our center, therate of minor complications was comparable to other centersin the world. But the rate of major surgical complications waslower than other centers.

  18. Developmental neuroplasticity after cochlear implantation.

    Science.gov (United States)

    Kral, Andrej; Sharma, Anu

    2012-02-01

    Cortical development is dependent on stimulus-driven learning. The absence of sensory input from birth, as occurs in congenital deafness, affects normal growth and connectivity needed to form a functional sensory system, resulting in deficits in oral language learning. Cochlear implants bypass cochlear damage by directly stimulating the auditory nerve and brain, making it possible to avoid many of the deleterious effects of sensory deprivation. Congenitally deaf animals and children who receive implants provide a platform to examine the characteristics of cortical plasticity in the auditory system. In this review, we discuss the existence of time limits for, and mechanistic constraints on, sensitive periods for cochlear implantation and describe the effects of multimodal and cognitive reorganization that result from long-term auditory deprivation. PMID:22104561

  19. Implant rehabilitation in bruxism patient.

    Science.gov (United States)

    Goiato, Marcelo Coelho; Sonego, Mariana Vilela; dos Santos, Daniela Micheline; da Silva, Emily Vivianne Freitas

    2014-01-01

    A white female patient presented to the university clinic to obtain implant retained prostheses. She had an edentulous maxillary jaw and presented three teeth with poor prognosis (33, 34 and 43). The alveolar bone and the surrounding tissues were healthy. The patient did not report any relevant medical history contraindicating routine dental treatment or implant surgery, but self-reported a dental history of asymptomatic nocturnal bruxism. The treatment plan was set and two Branemark protocols supported by six implants in each arch were installed after a 6-month healing period. A soft occlusal splint was made due to the patient's history of bruxism, and the lack of its use by the patient resulted in an acrylic fracture. The prosthesis was repaired and the importance of using the occlusal splint was restated. In the 4-year follow-up no fractures were reported. PMID:24907215

  20. Treatment of Infected Facial Implants.

    Science.gov (United States)

    Mohan, Kriti; Cox, Joshua A; Dickey, Ryan M; Gravina, Paula; Echo, Anthony; Izaddoost, Shayan A; Nguyen, Anh H

    2016-05-01

    Alloplastic facial implants have a wide range of uses to achieve the appropriate facial contour. A variety of materials such as metals, polymers, ceramics and synthetic injectable fillers are available to the reconstructive and aesthetic surgeon. Besides choosing the right surgical technique and the adequate material, the surgeon must be prepared to treat complications. Infection is an uncommon but serious complication that can cause displeasing consequences for the patient. There are few references in literature regarding treatment and management of facial implant-related infections. This study aims to discuss the role of biofilm in predisposing alloplastic materials to infection, to provide a review of literature, to describe our own institutional experience, and to define a patient care pathway for facial implant-associated infection. PMID:27152100

  1. Tinting of intraocular lens implants

    Energy Technology Data Exchange (ETDEWEB)

    Zigman, S.

    1982-06-01

    Intraocular lens (IOL) implants of polymethyl methacrylate (PMMA) lack an important yellow pigment useful as a filter in the visual process and in the protection of the retina from short-wavelength radiant energy. The ability to produce a yellow pigment in the PMMA used in IOL implants by exposure to near-ultraviolet (UV) light was tested. It was found that the highly cross-linked material in Copeland lens blanks was tinted slightly because of this exposure. The absorptive properties of lens blanks treated with near-UV light in this way approached that of the absorptive properties of human lenses. This finding shows that it is possible to alter IOL implants simply so as to induce a pale-yellow pigment in them to improve the visual process and to protect the retinas of IOL users.

  2. Optical effects of ion implantation

    International Nuclear Information System (INIS)

    This book, the thirteenth in the series ''Cambridge Studies in Modern Optics,'' represents the first attempt to provide a detailed description of the factors and processes that govern the optical properties of ion implanted materials. It begins with a survey of the basic physics and practical methods involved, then goes on to discuss the topics of optical absorption and luminescence. The authors present the basic theory of optical waveguides and their analysis and examine how ion implantation can be used in the production of optical waveguides. The concluding chapter deals with the progress being made in the development of device-oriented waveguide structures and how ion implantation is being used to achieve these ends

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

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, M.

    2008-07-01

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

  4. Numerical simulation of strain-adaptive bone remodelling in the ankle joint

    Directory of Open Access Journals (Sweden)

    Stukenborg-Colsman Christina

    2011-07-01

    Full Text Available Abstract Background The use of artificial endoprostheses has become a routine procedure for knee and hip joints while ankle arthritis has traditionally been treated by means of arthrodesis. Due to its advantages, the implantation of endoprostheses is constantly increasing. While finite element analyses (FEA of strain-adaptive bone remodelling have been carried out for the hip joint in previous studies, to our knowledge there are no investigations that have considered remodelling processes of the ankle joint. In order to evaluate and optimise new generation implants of the ankle joint, as well as to gain additional knowledge regarding the biomechanics, strain-adaptive bone remodelling has been calculated separately for the tibia and the talus after providing them with an implant. Methods FE models of the bone-implant assembly for both the tibia and the talus have been developed. Bone characteristics such as the density distribution have been applied corresponding to CT scans. A force of 5,200 N, which corresponds to the compression force during normal walking of a person with a weight of 100 kg according to Stauffer et al., has been used in the simulation. The bone adaptation law, previously developed by our research team, has been used for the calculation of the remodelling processes. Results A total bone mass loss of 2% in the tibia and 13% in the talus was calculated. The greater decline of density in the talus is due to its smaller size compared to the relatively large implant dimensions causing remodelling processes in the whole bone tissue. In the tibia, bone remodelling processes are only calculated in areas adjacent to the implant. Thus, a smaller bone mass loss than in the talus can be expected. There is a high agreement between the simulation results in the distal tibia and the literature regarding. Conclusions In this study, strain-adaptive bone remodelling processes are simulated using the FE method. The results contribute to a better

  5. Biomechanical Aspects of Shoulder and Hip Articulations: A Comparison of Two Ball and Socket Joints

    Directory of Open Access Journals (Sweden)

    Mustafa Qusay Ismael

    2006-01-01

    different for the two joints. Results obtained from the finite element analysis were important in understanding the areas of stress concentration and were thoroughly explained from the anatomical point of view and linked to muscle and joint capsule attachments. The model of the joints developed in this study can be used as a computational tool to joint biomechanics and to prosthetic implant analysis. Keywords: hip joint, shoulder joint, finite element analysis, biomechanics.

  6. In-vivo degradation mechanism of Ti-6Al-4V hip joints

    DEFF Research Database (Denmark)

    Lomholt, Trine Colding; Pantleon, Karen; Somers, Marcel A. J.

    2011-01-01

    In-vivo exposed Ti-6Al-4V implants were investigated to determine the degradation mechanism occurring during the articulating movements of the hip joint in the human body. Failed implants were compared to Ti-6Al-4V samples, which were tested in the laboratory for their tribocorrosion performance....... was concluded to be of combined mechanical and chemical nature. Wear debris is formed and accumulated in large flakes (>100μm). Upon further sliding the flakes are pressed into the surface and ultimately crushed into small, brittle particulate debris (...

  7. Joint annual report 1984

    International Nuclear Information System (INIS)

    An account is given on the activities in nuclear and solid state physcis. In the field of relativistic nuclear physcis first measurements at the Synchrophasotron of the JINR Dubna are presented. Nuclear reactions with heavy ions have been investigated at the cyclotron U-300 of the JINR. Studies of few-nucleon problems and measurements of fission cross sections at the tandem accelerator at Rossendorf have been continued. High spin states in transition nuclei (A approximately 80) and semimagic nuclei have been studied. Works in nuclear theory comprise heavy ion physics, plasma transitions in hot nuclear matter, antikaon production, hypernuclei and deformed nuclei, the time-dependent Hartree-Fock method, meson exchange, and new aspects of shell models. Various studies in solid state physics are presented, including the following: high-dose implantation in metals and semiconductors, tempering in semiconductor materials, light pulse annealing in Si, neutron diffraction in texture analysis, application of Si in the field of sensor technology

  8. Mutation breeding by ion implantation

    Science.gov (United States)

    Yu, Zengliang; Deng, Jianguo; He, Jianjun; Huo, Yuping; Wu, Yuejin; Wang, Xuedong; Lui, Guifu

    1991-07-01

    Ion implantation as a new mutagenic method has been used in the rice breeding program since 1986, and for mutation breeding of other crops later. It has been shown, in principle and in practice, that this method has many outstanding advantages: lower damage rate; higher mutation rate and wider mutational spectrum. Many new lines of rice with higher yield rate; broader disease resistance; shorter growing period but higher quality have been bred from ion beam induced mutants. Some of these lines have been utilized for the intersubspecies hybridization. Several new lines of cotton, wheat and other crops are now in breeding. Some biophysical effects of ion implantation for crop seeds have been studied.

  9. FDA Approves Eye Implant for Aging Boomers

    Science.gov (United States)

    ... medlineplus/news/fullstory_159648.html FDA Approves Eye Implant for Aging Boomers Tiny lens reshapes cornea to ... 2016 THURSDAY, June 30, 2016 (HealthDay News) -- An implant that helps the aging eye focus on small ...

  10. FDA Approves Implant to Battle Opioid Addiction

    Science.gov (United States)

    ... gov/medlineplus/news/fullstory_159050.html FDA Approves Implant to Battle Opioid Addiction Experts say steady dosing ... 26, 2016 (HealthDay News) -- A new long-acting implant that can help treat people addicted to heroin ...

  11. Dental implant surgery: planning and guidance

    International Nuclear Information System (INIS)

    A prototype application has been developed for interactive planning of dental implants on the EasyVision workstation. The user is led step by step via virtual positioning of the implant to the design of a customized drill guide. (orig.)

  12. Proton implanted sapphire planar and channel waveguides

    NARCIS (Netherlands)

    Laversenne, L.; Crunteanu, A.; Hoffmann, P.; Pollnau, M.; Moretti, P.; Mugnier, J.

    2003-01-01

    We report low-order transverse-mode planar waveguides in sapphire fabricated for the first time by proton implantation. The waveguides show good guiding properties without post-implantation annealing. Channel waveguiding was achieved by polyimide strip-loading.

  13. Neutrophil Responses to Sterile Implant Materials.

    Directory of Open Access Journals (Sweden)

    Siddharth Jhunjhunwala

    Full Text Available In vivo implantation of sterile materials and devices results in a foreign body immune response leading to fibrosis of implanted material. Neutrophils, one of the first immune cells to be recruited to implantation sites, have been suggested to contribute to the establishment of the inflammatory microenvironment that initiates the fibrotic response. However, the precise numbers and roles of neutrophils in response to implanted devices remains unclear. Using a mouse model of peritoneal microcapsule implantation, we show 30-500 fold increased neutrophil presence in the peritoneal exudates in response to implants. We demonstrate that these neutrophils secrete increased amounts of a variety of inflammatory cytokines and chemokines. Further, we observe that they participate in the foreign body response through the formation of neutrophil extracellular traps (NETs on implant surfaces. Our results provide new insight into neutrophil function during a foreign body response to peritoneal implants which has implications for the development of biologically compatible medical devices.

  14. Elderly Benefit from Using Implantable Defibrillators

    Science.gov (United States)

    ... org Learn More Elderly benefit from using implantable defibrillators June 17, 2013 Categories: Heart News Study Highlights: Older people may benefit from implantable cardioverter defibrillators (ICDs) as much as younger people. Overall health, ...

  15. Clinical management of implant prostheses in patients with bruxism

    OpenAIRE

    Osamu Komiyama; Frank Lobbezoo; Antoon De Laat; Takashi Iida; Tsuyoshi Kitagawa; Hiroshi Murakami; Takao Kato; Misao Kawara

    2012-01-01

    There is general agreement that excessive stress to the bone-implant interface may result in implant overload and failure. Early failure of the implant due to excessive loading occurs shortly after uncovering the implant. Excess load on a final restoration after successful implant integration can result in physical failure of the implant structure. Many clinicians believe that overload of dental implants is a risk factor for vertical peri-implant bone loss and/or may be detrimental for the su...

  16. Joint Advisory Appeals Board

    CERN Multimedia

    2003-01-01

    The Joint Advisory Appeals Board was convened to examine the appeal lodged by Mr Poul Frandsen concerning his assimilation into the new career structure. As the appellant has not objected, the report of the Board and the final decision of the Director-General are brought to the notice of the personnel in accordance with Article R VI 1.20 of the Staff Regulations. The relevant documents will therefore be posted on the notice boards of the Administration Building (N° 60) from 13 to 24 January 2003. Human Resources Division Tel. 74128

  17. Posttraumatic temporomandibular joint disorders.

    Science.gov (United States)

    Giannakopoulos, Helen E; Quinn, Peter D; Granquist, Eric; Chou, Joli C

    2009-05-01

    The temporomandibular joint (TMJ) has many essential functions. None of its components are exempt from injury. Facial asymmetry, malocclusion, disturbances in growth, osteoarthritis, and ankylosis can manifest as complications from trauma to the TMJ. The goals of initial treatment include achievement of pretraumatic function, restoration of facial symmetry, and resolution of pain. These same objectives hold true for late repairs and reconstruction of the TMJ apparatus. Treatment is demanding, and with opposing approaches. The following article explores various treatment options for problems presenting as a result of a history of trauma to the TMJ. PMID:22110802

  18. THE JOINT MONITORING COMMISSION

    Directory of Open Access Journals (Sweden)

    Helmoed-Römer Heitman

    2012-02-01

    Full Text Available The Joint Monitoring Commission (JMC was created to oversee the withdrawal of South African forces from the portion of Angola's southern Cunene province in which they had operated for some time, and its re-occupation by the Angolan Armed Forces (Fapla. It was to ensure that neither Swapo nor Cuban forces moved into this area as the South African Defence Force (SADF withdrew. The JMC consisted of SADF and Fapla headquarters (HQ personnel and infantry from both armies to monitor the area concerned. It operated in southern Angola from February 1984 to May 1985.

  19. Joint Advisory Appeals Board

    CERN Multimedia

    2003-01-01

    The Joint Advisory Appeals Board was convened to examine the appeal lodged by Mr Aloïs Girardoz with regard to classification and advancement. As the appellant has not objected, the Board's report and the Director-General's decision will be brought to the notice of the personnel in accordance with Article R VI 1.20 of the Staff Regulations. The relevant documents will therefore be posted on the notice boards of the Administration Building (N° 60) from 15 to 29 August 2003. Human Resources Division Tel. 74128

  20. JOINT ADVISORY APPEALS BOARD

    CERN Multimedia

    Personnel Division

    1999-01-01

    The Joint Advisory Appeals Board was convened to examine the appeal lodged by Mr Joào Bento with regard to residential category. As the appellant has not objected, the recommendations of the Board and the final decision of the Director-General are brought to the notice of the personnel in accordance with Article RÊVIÊ1.20 of the Staff Regulations.The relevant documents will therefore be posted on the notice boards of the Administration Building (N¡ 60) from 29 October to 12 November 1999.Personnel DivisionTel. 74128

  1. Surgery center joint ventures.

    Science.gov (United States)

    Zasa, R J

    1999-01-01

    Surgery centers have been accepted as a cost effective, patient friendly vehicle for delivery of quality ambulatory care. Hospitals and physician groups also have made them the vehicles for coming together. Surgery centers allow hospitals and physicians to align incentives and share benefits. It is one of the few types of health care businesses physicians can own without anti-fraud and abuse violation. As a result, many surgery center ventures are now jointly owned by hospitals and physician groups. This article outlines common structures that have been used successfully to allow both to own and govern surgery centers.

  2. Acromioclavicular Joint Reconstruction.

    Science.gov (United States)

    Scillia, Anthony J; Cain, E Lyle

    2015-12-01

    Our technique for acromioclavicular joint reconstruction provides a variation on coracoclavicular ligament reconstruction to also include acromioclavicular ligament reconstruction. An oblique acromial tunnel is drilled, and the medial limb of the gracilis graft, after being crossed and passed beneath the coracoid and through the clavicle, is passed through this acromial tunnel and sutured to the trapezoid graft limb after appropriate tensioning. Tenodesis screws are not placed in the bone tunnels to avoid graft fraying, and initial forces on the graft are offloaded with braided absorbable sutures passed around the clavicle. PMID:27284528

  3. Optical rotary joint

    Science.gov (United States)

    May, R. G., Jr.

    1982-06-01

    The primary objective of this contract is the design, fabrication, and testing of an optical rotary joint which permits transmission of signals through optical fibers across the interface of two environments rotating relative to each other. Outstanding optical performance is achieved through the use of gradient index lenses to couple radiation across the separation between two fibers. The salient features of this device are bidirectional operation at two wavelengths (850 nm and 1300 nm), low insertion loss, low rotationally induced variation of attenuation, a seven-circuit electrical slip-ring assembly, and rugged construction. The device is designed to facilitate the application of future designs to pressurized, subsea environments.

  4. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2008-01-01

    The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel against the decision to grant him only a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the attention of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main building (bldg. 500) from 1 September to 14 September 2008. Human Resources Department (73911)

  5. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2008-01-01

    The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel against the decision to grant him only a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the attention of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main Building (Bldg. 500) from 1 September to 14 September 2008. Human Resources Department (73911)

  6. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2007-01-01

    The Joint Advisory Appeals Board was convened to examine an internal appeal lodged by a member of the personnel with regard to the decision not to grant him an indefinite contract. The person concerned has requested that the report of the Board and the final decision of the Director-General be brought to the notice of the members of the personnel, in accordance with Article R VI 1.18 of the Staff Regulations. The relevant documents will therefore be posted on the notice board of the Main building (Bldg. 60) from 24 September to 7 October 2007. Human Resources Department

  7. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2008-01-01

    The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel with regard to the decision not to grant him an indefinite contract. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the notice of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main Building (Bldg. 500) from 26 May to 6 June 2008. Human Resources Department (73911)

  8. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2008-01-01

    The Joint Advisory Appeals Board was convened to examine an internal appeal lodged by a member of the personnel with regard to the decision not to grant him an indefinite contract. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the notice of the members of the personnel, in accordance with Article R VI 1.18 of the Staff Regulations. These documents will therefore be posted on the notice board of the Main Building (Bldg. 60) from 21 January to 3 February 2008. Human Resources Department (73911)

  9. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2006-01-01

    The Joint Advisory Appeals Board was convened to examine an appeal lodged by a member of the personnel with regard to advancement. The person concerned has requested that the report of the Board and the final decision of the Director-General be brought to the notice of the personnel in accordance with Article R VI 1.20 of the Staff Regulations. The relevant documents will therefore be posted on the notice boards of the Administration Building (No. 60) from 24 March to 10 April 2006. Human Resources Department Tel. 74128

  10. Joint Advisory Appeals Board

    CERN Multimedia

    HR Department

    2008-01-01

    The Joint Advisory Appeals Board has examined the internal appeal lodged by a member of the personnel with regard to the decision not to award him a periodic one-step advancement for the 2006 reference year. The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the notice of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be posted on the notice board of the Main building (Bldg. 500) from 17 March to 30 March 2008. Human Resources Department Tel. 73911

  11. Joint Advisory Appeals Board

    CERN Multimedia

    2013-01-01

    The Joint Advisory Appeals Board has examined the internal appeal lodged by a former member of the personnel, a beneficiary of the CERN Pension Fund, against the calculation of his pension in the framework of the Progressive Retirement Programme.   The person concerned has not objected to the report of the Board and the final decision of the Director-General being brought to the attention of the members of the personnel. In application of Article R VI 1.18 of the Staff Regulations, these documents will therefore be available from 26 July to 11 August 2013 at the following link. HR Department Head Office

  12. Lisfranc Joint Injuries

    Institute of Scientific and Technical Information of China (English)

    Lisa Chinn

    2009-01-01

    @@ The ankle and foot are the most common sites for athletic injuries.[1]Midfoot,or Lisfranc,injuries are the second most common foot injury and have a high in cidence in particular sports.They account for 4% of all football injuries per year,occurring frequently in linemen.[2]They are also common in equestrians,surfers,and windsurfers.[2]Lisfranc injuries are often misdiagnosed and if not treated properly can have lingering symptoms.It is estimated that Lisfranc joint injuries occur in 1 in every 55,000 persons every year.[3,4

  13. Hip arthroplasty for treatment of advanced osteonecrosis: comprehensive review of implant options, outcomes and complications

    Directory of Open Access Journals (Sweden)

    Waewsawangwong W

    2016-06-01

    Full Text Available Warit Waewsawangwong, Pirapat Ruchiwit, James I Huddleston, Stuart B Goodman Department of Orthopedic Surgery, Stanford University, Stanford, CA, USA Abstract: Surgical treatment for late stage (post-collapse osteonecrosis of the femoral head is controversial. In these situations, the outcome of joint preservation procedures is poor. There are several arthroplasty options for late-stage disease. The clinical outcomes of hemiarthroplasty and hemiresurfacing are unpredictable because of progressive acetabular cartilage degeneration. Total hip resurfacing may be associated with further vascular insult to the femoral head and early failure of the implant. Total hip replacement with metal-on-conventional polyethylene bearing surfaces has been the gold standard, but implant survivorship is limited in young active patients due to wear and osteolysis. Newer alternative bearing surfaces may have improved wear characteristics, but their durability must be confirmed in longer-term studies. Keywords: hip arthroplasty, advanced osteonecrosis, implant options, outcomes, complications

  14. Impact of cone-beam computed tomography on implant planning and on prediction of implant size

    Energy Technology Data Exchange (ETDEWEB)

    Pedroso, Ludmila Assuncao de Mello; Silva, Maria Alves Garcia Santos, E-mail: ludmilapedroso@hotmail.com [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia; Garcia, Robson Rodrigues [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Medicina Oral; Leles, Jose Luiz Rodrigues [Universidade Paulista (UNIP), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Cirurgia; Leles, Claudio Rodrigues [Universidade Federal de Goias (UFG), Goiania, GO (Brazil). Fac. de Odontologia. Dept. de Prevencao e Reabilitacao Oral

    2013-11-15

    The aim was to investigate the impact of cone-beam computed tomography (CBCT) on implant planning and on prediction of final implant size. Consecutive patients referred for implant treatment were submitted to clinical examination, panoramic (PAN) radiography and a CBCT exam. Initial planning of implant length and width was assessed based on clinical and PAN exams, and final planning, on CBCT exam to complement diagnosis. The actual dimensions of the implants placed during surgery were compared with those obtained during initial and final planning, using the McNemmar test (p < 0.05). The final sample comprised 95 implants in 27 patients, distributed over the maxilla and mandible. Agreement in implant length was 50.5% between initial and final planning, and correct prediction of the actual implant length was 40.0% and 69.5%, using PAN and CBCT exams, respectively. Agreement in implant width assessment ranged from 69.5% to 73.7%. A paired comparison of the frequency of changes between initial or final planning and implant placement (McNemmar test) showed greater frequency of changes in initial planning for implant length (p < 0.001), but not for implant width (p = 0.850). The frequency of changes was not influenced by implant location at any stage of implant planning (chi-square test, p > 0.05). It was concluded that CBCT improves the ability of predicting the actual implant length and reduces inaccuracy in surgical dental implant planning. (author)

  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. PMID:27126410

  16. Effect of Implantation Machine Parameters on N+ ion Implantation for Upland Cotton (Gossypium hirsutum L.) Pollen

    Institute of Scientific and Technical Information of China (English)

    YUE Jieyu; YU Lixiang; WU Yuejin; TANG Canming

    2008-01-01

    Effect of parameters of ion implantation machine,including ion energy,total dose,dose rate,impulse energy and implantation interval on the pollen grains of upland cotton implanted with nitrogen ion beam were studied.The best parameters were screened out.The results also showed that the vacuum condition before the nitrogen ion implantation does not affect the pollen viability.

  17. Effects of surface coating on reducing friction and wear of orthopaedic implants

    OpenAIRE

    Hee Ay Ching; Dipankar Choudhury; Md Julker Nine; Noor Azuan Abu Osman

    2014-01-01

    Coatings such as diamond-like carbon (DLC) and titanium nitride (TiN) are employed in joint implants due to their excellent tribological properties. Recently, graphite-like carbon (GLC) and tantalum (Ta) have been proven to have good potential as coating as they possess mechanical properties similar to bones—high hardness and high flexibility. The purpose of this systematic literature review is to summarize the coating techniques of these four materials in order to compare their mechanical pr...

  18. Selection of an animal model for implant fixation studies: anatomical aspects.

    OpenAIRE

    Goel, V. K.; Drinker, H.; Panjabi, M. M.; Strongwater, A.

    1982-01-01

    A number of different animal models have been employed by investigators to study the biology of the bone-cement interface as it relates to the problem of hip implant loosening in humans. This study compares to the human three species (baboon, dog, and sheep) currently under use as experimental animal models from an anatomical point of view. A number of parameters, important for the dimensional design of a femoral prosthesis, loads at the hip joint and its subsequent performance, were used for...

  19. 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

  20. Early Loaded Single Implant Reinforced Mandibular Overdenture

    OpenAIRE

    Nischal, K; Chowdhary, R.

    2016-01-01

    Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. ...

  1. Augmentation Mammaplasty Using Implants: A Review

    Directory of Open Access Journals (Sweden)

    Susumu Takayanagi

    2012-09-01

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

  2. Implant fractures: Rare but not exceptional

    OpenAIRE

    Sahitya Sanivarapu; Srinivas Moogla; Rupa Sruthi Kuntcham; Lakshmi Kanth Kolaparthy

    2016-01-01

    Fabrication of dentures aided with implants has become a preferred treatment option for rehabilitation of completely and partially edentulous patients when durability is concerned. Simulation to natural teeth in terms of esthetics and to a greater extent in function can be considered as key elements in the raise of implant dentistry worldwide. Despite its high success rate, therapy with osseointegrated dental implants is not free of complications. Implant failure can occur for other reasons, ...

  3. Factors affecting peri-implant tissue reactions

    OpenAIRE

    Hultin, Margareta

    2001-01-01

    Screw- shaped titanium implants are today routinely used m the substitution of lost teeth. In this thesis some of the biological factors related to the long-term survival and maintenance of dental implants were studied. The first arm of these studies was to evaluate the neutrophil activation around teeth and dental implants (Papers I & II). Secondly we wanted to evaluate the clinical radiographic and microbiological status of implants after long-term. function m partly e...

  4. Environmental standards for intraocular lens implantation.

    Science.gov (United States)

    Crawford, B A; Kaufman, D V

    1984-02-01

    Successful implantation of prosthetic devices depends upon their freedom from postoperative inflammation and infection. Techniques and lessons learned in orthopaedic and other implant surgery should be applied to intraocular lens implantation. The avoidance of contamination by particles and micro-organisms is one essential principle of the surgical procedure. Practical steps are described to reduce both types of contamination. These measures taken together are recommended for adoption as a standard of environmental safety for lens implantation.

  5. CT-based Individualized Medical Implant Design

    Institute of Scientific and Technical Information of China (English)

    叶铭; 朱晓峰; 主成焘; 孙坚

    2003-01-01

    Most implantation cases are implemented using implants selected from the available standard set, but in some cases, only those implants conforming to individual patient's skeletal morphology can serve the purpose. This paper proposes a new approach to design and fabricate custom-made exact-fit medical implants. With a real surgical case as the example,technical design details are presented; and three algorithms are given respectively for segmentation based on object features, triangular mesh defragmentation and mesh cutting.

  6. Assessing legal responsibility for implant failure.

    Science.gov (United States)

    Palat, M

    1991-04-01

    The number of malpractice suits related to implants has recently increased significantly, with awards that are among the largest in dentistry. This article discusses the principles involved in assessing liability for implant failure and the various clinical situations that can affect liability in implant practice. The author also provides a list of the interrogatories required of defendants in malpractice suits related to implants. PMID:1893392

  7. Detailed spectral analysis of decellularized skin implants

    Science.gov (United States)

    Timchenko, E. V.; Timchenko, P. E.; Volova, L. T.; Dolgushkin, D. A.; Shalkovsky, P. Y.; Pershutkina, S. V.

    2016-08-01

    The resutls of detailed analysis of donor skin implants using Raman spectroscopy method are presented. Fourier-deconvolution method was used to separate overlapping spectrum lines and to improve its informativeness. Based on the processed spectra were introduced coefficients that represent changes in relative concentration of implant components, which determines the quality of implants. It was established that Raman spectroscopy method can be used in assessment of skin implants.

  8. Implant surface preparation in the surgical treatment of experimental peri-implantitis with autogenous bone graft and ePTFE membrane in cynomolgus monkeys

    DEFF Research Database (Denmark)

    Schou, Søren; Holmstrup, Palle; Jørgensen, Torben;

    2003-01-01

    peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology......peri-implantitis; treatment; implant surface preparation; nonhuman primates; histology; stereology...

  9. The endometrial factor in human embryo implantation

    NARCIS (Netherlands)

    Boomsma, C.M.

    2009-01-01

    The studies presented in this thesis aimed to explore the role of the endometrium in the implantation process. At present, embryo implantation is the major rate-limiting step for success in fertility treatment. Clinicians have sought to develop clinical interventions aimed at enhancing implantation

  10. An Uncommon Presentation of Breast Implant Rupture.

    Science.gov (United States)

    Koh, Eugene; Watson, David I; Dean, Nicola R

    2016-05-01

    Late periprosthetic seroma has lately been concerning for breast implant-associated anaplastic large cell lymphoma. The authors present an uncommon presentation of breast implant rupture with a seroma and skin rash forming 2 years after insertion of the implant. PMID:27579243

  11. Implant supported overdentures--the Copenhagen experience

    DEFF Research Database (Denmark)

    Gotfredsen, K

    1997-01-01

    OBJECTIVES: To evaluate the functional and biological effect of implant-supported overdenture treatment in the lower jaw. METHODS AND MATERIALS: Thirty-two patients were consecutively treated with Astra Tech implants in the lower jaw for retaining overdentures. All implants had a diameter of 3.5 ...

  12. The Case for a Generic Implant Processor

    NARCIS (Netherlands)

    Strydis, C.; Gaydadjiev, G.N.

    2008-01-01

    A more structured and streamlined design of implants is nowadays possible. In this paper we focus on implant processors located in the heart of implantable systems. We present a real and representative biomedical-application scenario where such a new processor can be employed. Based on a suitably se

  13. 21 CFR 888.3410 - Hip joint metal/polymer or ceramic/polymer semiconstrained resurfacing cemented prosthesis.

    Science.gov (United States)

    2010-04-01

    ... semiconstrained resurfacing cemented prosthesis. 888.3410 Section 888.3410 Food and Drugs FOOD AND DRUG... prosthesis. (a) Identification. A hip joint metal/polymer or ceramic/polymer semi-constrained resurfacing cemented prosthesis is a two-part device intended to be implanted to replace the articulating surfaces...

  14. Laser Welded versus Resistance Spot Welded Bone Implants: Analysis of the Thermal Increase and Strength

    Directory of Open Access Journals (Sweden)

    Carlo Fornaini

    2014-01-01

    Full Text Available Introduction. The first aim of this “ex vivo split mouth” study was to compare the thermal elevation during the welding process of titanium bars to titanium implants inserted in pig jaws by a thermal camera and two thermocouples. The second aim was to compare the strength of the joints by a traction test with a dynamometer. Materials and Methods. Six pigs’ jaws were used and three implants were placed on each side of them for a total of 36 fixtures. Twelve bars were connected to the abutments (each bar on three implants by using, on one side, laser welding and, on the other, resistance spot welding. Temperature variations were recorded by thermocouples and by thermal camera while the strength of the welded joint was analyzed by a traction test. Results. For increasing temperature, means were 36.83 and 37.06, standard deviations 1.234 and 1.187, and P value 0.5763 (not significant. For traction test, means were 195.5 and 159.4, standard deviations 2.00 and 2.254, and P value 0.0001 (very significant. Conclusion. Laser welding was demonstrated to be able to connect titanium implant abutments without the risk of thermal increase into the bone and with good results in terms of mechanical strength.

  15. Jointly Sponsored Research Program

    Energy Technology Data Exchange (ETDEWEB)

    Everett A. Sondreal; John G. Hendrikson; Thomas A. Erickson

    2009-03-31

    U.S. Department of Energy (DOE) Cooperative Agreement DE-FC26-98FT40321 funded through the Office of Fossil Energy and administered at the National Energy Technology Laboratory (NETL) supported the performance of a Jointly Sponsored Research Program (JSRP) at the Energy & Environmental Research Center (EERC) with a minimum 50% nonfederal cost share to assist industry in commercializing and effectively applying highly efficient, nonpolluting energy systems that meet the nation's requirements for clean fuels, chemicals, and electricity in the 21st century. The EERC in partnership with its nonfederal partners jointly performed 131 JSRP projects for which the total DOE cost share was $22,716,634 (38%) and the nonfederal share was $36,776,573 (62%). Summaries of these projects are presented in this report for six program areas: (1) resource characterization and waste management, (2) air quality assessment and control, (3) advanced power systems, (4) advanced fuel forms, (5) value-added coproducts, and (6) advanced materials. The work performed under this agreement addressed DOE goals for reductions in CO{sub 2} emissions through efficiency, capture, and sequestration; near-zero emissions from highly efficient coal-fired power plants; environmental control capabilities for SO{sub 2}, NO{sub x}, fine respirable particulate (PM{sub 2.5}), and mercury; alternative transportation fuels including liquid synfuels and hydrogen; and synergistic integration of fossil and renewable resources.

  16. Joint collaborative technology experiment

    Science.gov (United States)

    Wills, Michael; Ciccimaro, Donny; Yee, See; Denewiler, Thomas; Stroumtsos, Nicholas; Messamore, John; Brown, Rodney; Skibba, Brian; Clapp, Daniel; Wit, Jeff; Shirts, Randy J.; Dion, Gary N.; Anselmo, Gary S.

    2009-05-01

    Use of unmanned systems is rapidly growing within the military and civilian sectors in a variety of roles including reconnaissance, surveillance, explosive ordinance disposal (EOD), and force-protection and perimeter security. As utilization of these systems grows at an ever increasing rate, the need for unmanned systems teaming and inter-system collaboration becomes apparent. Collaboration provides a means of enhancing individual system capabilities through relevant data exchange that contributes to cooperative behaviors between systems and enables new capabilities not possible if the systems operate independently. A collaborative networked approach to development holds the promise of adding mission capability while simultaneously reducing the workload of system operators. The Joint Collaborative Technology Experiment (JCTE) joins individual technology development efforts within the Air Force, Navy, and Army to demonstrate the potential benefits of interoperable multiple system collaboration in a force-protection application. JCTE participants are the Air Force Research Laboratory, Materials and Manufacturing Directorate, Airbase Technologies Division, Force Protection Branch (AFRL/RXQF); the Army Aviation and Missile Research, Development, and Engineering Center Software Engineering Directorate (AMRDEC SED); and the Space and Naval Warfare Systems Center - Pacific (SSC Pacific) Unmanned Systems Branch operating with funding provided by the Joint Ground Robotics Enterprise (JGRE). This paper will describe the efforts to date in system development by the three partner organizations, development of collaborative behaviors and experimentation in the force-protection application, results and lessons learned at a technical demonstration, simulation results, and a path forward for future work.

  17. Chemical, Corrosion and Topographical Analysis of Stainless Steel Implants after Different Implantation Periods

    OpenAIRE

    Chrzanowski, Wojciech; Armitage, David Andrew; Knowles, Jonathan Campbell; Szade, Jacek; Korlacki, Wojciech; Marciniak, Jan

    2008-01-01

    Abstract The aim of this work is to examine the corrosion properties, chemical composition, and material?implant interaction after different periods of implantation of plates used to correct funnel chest. The implants are made of 316L stainless steel. Examinations are carried out on three implants: new (nonimplanted) and two implanted for 29 and 35 months. The corrosion study reveals that in the potential range that could occur in the physiological condition the new bar has the low...

  18. Investigation of the Effects of Abutment and Implant Length on Stability of Short Dental Implants

    OpenAIRE

    Eda OZYILMAZ; Aykul, Halil; OZYILMAZ, Emre; Dalkiz, Mehmet; M. Burak BİLGİN

    2015-01-01

    The use of dental implants to solve different problems in dentistry has been growing rapidly. The success rates of dental implants are also very important for patients. Depending on the bone level of patients, short dental implants are very popular and widely used by many dentists. Although many dentists are using short dental implants frequently, It can be guessed that there can be stability problems because of crown to implant ratios. In this study, it is aimed to find out...

  19. Cortical plasticity after cochlear implantation

    DEFF Research Database (Denmark)

    Petersen, B; Gjedde, A; Wallentin, M;

    2013-01-01

    The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen...

  20. Cortical Plasticity after Cochlear Implantation

    Science.gov (United States)

    Petersen, B.; Gjedde, A.; Wallentin, M.; Vuust, P.

    2013-01-01

    The most dramatic progress in the restoration of hearing takes place in the first months after cochlear implantation. To map the brain activity underlying this process, we used positron emission tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca's area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca's area in restoration of speech perception, but only in individuals in whom Broca's area has been active prior to the loss of hearing. PMID:24377050

  1. Reading skills after cochlear implantation

    NARCIS (Netherlands)

    Vermeulen, Agnes Maria

    2007-01-01

    It has frequently been found that profoundly deaf children with conventional hearing aids have difficulties with the comprehension of written text. Cochlear Implants (CIs) were expected to enhance the reading comprehension of these profoundly deaf children because they provide auditory access to spo

  2. Digital planning of cranial implants

    NARCIS (Netherlands)

    van der Meer, Wicher J.; Bos, Ruud R. M.; Vissink, Arjan; Visser, Anita

    2013-01-01

    Computer-aided techniques can be used in the reconstruction of defects in the skull, although there are limitations for large defects. We describe a technique for the digital design of an implant for cranioplasty using one, easy-to-use, piece of generic industrial software that shows a curvature-bas

  3. Carbon coatings for medical implants

    Directory of Open Access Journals (Sweden)

    K. Bakowicz-Mitura

    2007-01-01

    Full Text Available Purpose: In this paper we report in vitro and in vivo results of Nanocrystalline Diamond Coatings whichare used in medicine onto medical implants The very important property of carbon coatings is the protectionliving organism against the metalosis. Different medical implants with complicated shapes are covering byNanocrystalline Diamond Coatings by RF dense plasma CVD.Design/methodology/approach: 1 Material characterizations of deposited coatings have been evaluated by using:Transmission Electron Microscopy (TEM, Scanning Electron Microscopy (SEM, Atomic Force Microscopy(AFM, Auger electron spectroscopy (AES, microX-Ray Spectroscopy and bend test 2 Biological investigationbased on: (a in vivo and (b in vitro examinations as well (c clinical investigations – contact allergy.Findings: It was revealed that Nanocrystalline Diamond Coatings form the barrier diffusion between implantand human environment as a consequence prevent leaching of metallic ions into the body. Additionally, theresearch on carbon coatings proved that diamond layers are biocompatible with living organism. Contact allergyon nickel is inhibited by diamond powders.Practical implications: Practical application metal implants with NCD in orthopedy, cardiosurgery, oralsurgery, maxillo-facial surgery and dermatology.Originality/value: We have observed anti-inflammatory, antiallergic and anticancerogenic responses from thecarbon coatings layers onto medical implants like wires and screws.

  4. Immediate loading of dental implants.

    Science.gov (United States)

    Henry, P J; Liddelow, G J

    2008-06-01

    The purpose of this review is to explore the concept of immediate loading as it pertains to dental implants and the indications for clinical practice. The definition of immediate loading will be considered together with a review of the relevant literature in an attempt to provide evidence-based guidelines for successful implementation into practice. A search of electronic databases including Medline, PubMed and the Cochrane Database of Systematic Reviews was undertaken using the terms "immediate loading'', "dental implants'', "immediate function'', "early loading'', "oral implants'', "immediate restoration'' and "systematic review''. This was supplemented by handsearching in peer-reviewed journals and cross-referenced with the articles accessed. Emphasis was given to systematic reviews and controlled clinical trials. A definition of immediate loading was suggested pertinent to the realities of logistics in clinical practice with respect to application and time frame. The literature was evaluated and shown to be limited with significant shortcomings. Guidelines and recommendations for clinical protocols were suggested and illustrated by examples of case types with a minimum of 1-3 years follow-up. A list of additional references for further reading was provided. Within the limitations of this review, there is evidence to suggest that immediate loading protocols have demonstrated high implant survival rates and may be cautiously recommended for certain clinical situations. However, more high level evidence studies, preferably randomized controlled trials (RCTs), over a long time frame are required to show a clear benefit over more conventional loading protocols.

  5. Annealing of ion implanted silicon

    International Nuclear Information System (INIS)

    The newer uses of ion implantation require a higher dose rate. This has led to the introduction of high beam current implanters; the wafers move in front of a stationary beam to give a scanning effect. This can lead to non-uniform heating of the wafer. Variations in the sheet resistance of the layers can be very non-uniform following thermal annealing. Non-uniformity in the effective doping both over a single wafer and from one wafer to another, can affect the usefulness of ion implantation in high dose rate applications. Experiments to determine the extent of non-uniformity in sheet resistance, and to see if it is correlated to the annealing scheme have been carried out. Details of the implantation parameters are given. It was found that best results were obtained when layers were annealed at the maximum possible temperature. For arsenic, phosphorus and antimony layers, improvements were observed up to 12000C and boron up to 9500C. Usually, it is best to heat the layer directly to the maximum temperature to produce the most uniform layer; with phosphorus layers however it is better to pre-heat to 10500C. (U.K.)

  6. OIG targets contractual joint ventures.

    Science.gov (United States)

    O'Hare, Patrick K

    2003-09-01

    A recent OIG Special Advisory Bulletin raises questions for providers involved in joint ventures. The Bulletin describes several characteristics that the OIG views as potentially suspect, including a referral stream controlled by the provider initiating the joint venture and the use of a wholly owned subsidiary of the provider to bill and collect for services. According to the OIG, profits paid by the subsidiary to the provider owner in such "suspect contractual joint ventures" could constitute illegal remuneration for referrals.

  7. Arthrography of the knee joint

    Energy Technology Data Exchange (ETDEWEB)

    Keyl, W.; Jaeger, M.

    1981-10-01

    The standardized examination technique and the clinical problems of the arthrographic mehtod applied on the knee joint is explained by the results obtained in 3000 examinations. Whereas the accuracy of the knee-joint arthrography provides a high degree in cases of meniscus lesions, computer tomography presents in chondral and capsular ligament lesions, and sonography in popliteal cysts better diagnostic information; but in any case arthroscopy gains more and more importance in knee-joint diagnostics.

  8. Goniometry in limited joint mobility

    OpenAIRE

    Gopinath, S.; Manoj, K.; Rubiya

    2012-01-01

    Aim: To study about the utility of goniometry in screening for limited joint mobility (LJM) in patients attending a secondary level Diabetic Clinic. Materials and Methods: Randomly selected data of 100 patients attending a secondary level diabetic clinic without any complications were used. Baseline neuropathy assessments, namely monofilament and biothesiometry were done. Range of movement around the ankle joint and 1 st metatarsal joint was done using goniometry. Both the results were compar...

  9. Variable Joint Elasticities in Running

    Science.gov (United States)

    Peter, Stephan; Grimmer, Sten; Lipfert, Susanne W.; Seyfarth, Andre

    In this paper we investigate how spring-like leg behavior in human running is represented at joint level. We assume linear torsion springs in the joints and between the knee and the ankle joint. Using experimental data of the leg dynamics we compute how the spring parameters (stiffness and rest angles) change during gait cycle. We found that during contact the joints reveal elasticity with strongly changing parameters and compare the changes of different parameters for different spring arrangements. The results may help to design and improve biologically inspired spring mechanisms with adjustable parameters.

  10. Effectiveness of Implant Therapy Analyzed in a Swedish Population: Prevalence of Peri-implantitis.

    Science.gov (United States)

    Derks, J; Schaller, D; Håkansson, J; Wennström, J L; Tomasi, C; Berglundh, T

    2016-01-01

    Peri-implantitis is an inflammatory disease affecting soft and hard tissues surrounding dental implants. As the global number of individuals that undergo restorative therapy through dental implants increases, peri-implantitis is considered as a major and growing problem in dentistry. A randomly selected sample of 588 patients who all had received implant-supported therapy 9 y earlier was clinically and radiographically examined. Prevalence of peri-implantitis was assessed and risk indicators were identified by multilevel regression analysis. Forty-five percent of all patients presented with peri-implantitis (bleeding on probing/suppuration and bone loss >0.5 mm). Moderate/severe peri-implantitis (bleeding on probing/suppuration and bone loss >2 mm) was diagnosed in 14.5%. Patients with periodontitis and with ≥4 implants, as well as implants of certain brands and prosthetic therapy delivered by general practitioners, exhibited higher odds ratios for moderate/severe peri-implantitis. Similarly, higher odds ratios were identified for implants installed in the mandible and with crown restoration margins positioned ≤1.5 mm from the crestal bone at baseline. It is suggested that peri-implantitis is a common condition and that several patient- and implant-related factors influence the risk for moderate/severe peri-implantitis (ClinicalTrials.gov NCT01825772). PMID:26701919

  11. Silver Nanocoating Technology in the Prevention of Prosthetic Joint Infection

    Directory of Open Access Journals (Sweden)

    Jiri Gallo

    2016-05-01

    Full Text Available Prosthetic joint infection (PJI is a feared complication of total joint arthroplasty associated with increased morbidity and mortality. There is a growing body of evidence that bacterial colonization and biofilm formation are critical pathogenic events in PJI. Thus, the choice of biomaterials for implanted prostheses and their surface modifications may significantly influence the development of PJI. Currently, silver nanoparticle (AgNP technology is receiving much interest in the field of orthopaedics for its antimicrobial properties and a strong anti-biofilm potential. The great advantage of AgNP surface modification is a minimal release of active substances into the surrounding tissue and a long period of effectiveness. As a result, a controlled release of AgNPs could ensure antibacterial protection throughout the life of the implant. Moreover, the antibacterial effect of AgNPs may be strengthened in combination with conventional antibiotics and other antimicrobial agents. Here, our main attention is devoted to general guidelines for the design of antibacterial biomaterials protected by AgNPs, its benefits, side effects and future perspectives in PJI prevention.

  12. Finite element analysis of the relationship between the fracture possibility and different implant angle of hip resurfacing arthroplasty

    International Nuclear Information System (INIS)

    Objective: To explore the biomechanics influences of the angle of femoral prosthesis implantation by constructing and analyzing different 3-D finite element (FE) Resurfacing Arthroplasty of Hip (RSAH) models. Methods: Six different implant angles of RSAH 3-D FE models were constructed based on the human data that had been collected with 16-slice spiral CT. The angle was 120°, 125°, 130°, 135°, 140°, and 145°, respectively. Joint loading and related muscle strength were applied. The regular pattern of the tensile/compressive stress distribution was analyzed and the ratios of nodes that tensile or compressive stress value exceeding the yield stress value on different models were calculated. Results: The neutrosphere location was changed when changing the femoral prosthesis implantation angle. The tensile area was decreased when increasing the femoral prosthesis implantation angle. When the angle was in the range of 135° to 145°, no node showing tensile/compressive stress value exceeding the yield stress value was found in the cancellous bone of femoral head and the cortical bone of femoral neck, and few such nodes in the cancellous bone of femoral neck (ratios were less than 0.3%). When the implant angle was lower than 135°, the ratios were increased significantly. Conclusion: The implant angle range from 135° to 145° can reduce the fracture possibility after RSAH with normal bone. The best angle of the femoral prosthesis implantation is 140°. (authors)

  13. Breast fibromatosis associated with breast implants.

    Science.gov (United States)

    Seo, Yoon Nae; Park, Young Mi; Yoon, Hye Kyoung; Lee, Sun Joo; Choo, Hye Jung; Ryu, Ji Hwa

    2015-09-01

    Fibromatosis refers to an extra-abdominal desmoid tumor or aggressive fibromatosis. Breast fibromatosis can develop in association with the capsule around a breast implant, although reports of cases of fibromatosis associated with breast implants are rare. As the demand for breast augmentation has increased, it is important to understand the diseases associated with breast implants. In the present report, we describe a case of breast fibromatosis that developed adjacent to a breast implant and demonstrated a relatively well-defined border even though it invaded the surrounding structures. We also explore the specific imaging features for diagnosing breast fibromatosis in association with implants by reviewing previous literature.

  14. Current Concepts in Restorative Implant Dentistry

    Institute of Scientific and Technical Information of China (English)

    Prof.Marchack

    2009-01-01

    Patients today are incteasingly aware of dental implants.and their expectations are for esthetically and functionally pleasingimplant restorations that mimic natural teeth.This presentation will give both the experienced and novice practitioner a better understand-ing of how restorative implant dentistry has evolved.Treatment planning and restorative options for single implants.multiple implants andfully edentulons arches will be discussed,and the use of modern materials and CADCAM technology in fabricating the most contemporaryfixed implant supported prostheses will be demonstrated.

  15. Choice of a dental implant system.

    Science.gov (United States)

    Hunt, Peter R; Gartner, Judith L; Norkin, Frederic J

    2005-04-01

    Many dentists are bewildered by the intricacies and complexities of dental implants. They are constantly besieged by product advertisements and can find it difficult to choose which systems to work with. Some dentists are so intimidated by the subject that they choose to avoid getting involved with implants and instead stick to traditional tooth replacement systems. By breaking implants down into 4 main components, the body, collar, connection, and restorative post, it is easier to understand the structure and function of dental implants. Each portion should be designed to achieve certain objectives. Once these structural components are understood, it is easier to compare and contrast differing implant systems.

  16. Stoichiometric disturbances in ion implanted silicon carbide

    Energy Technology Data Exchange (ETDEWEB)

    Morvan, E.; Monserrat, J.; Rebollo, J.; Flores, D.; Jorda, X. [Centro Nacional de Microelectronica, Barcelona (Spain); Locatelli, M.L.; Ottaviani, L. [CEGELY ECPA, INSA de Lyon, Villeurbanne (France)

    1998-08-01

    Monte Carlo simulations of stoichiometric disturbances induced by ion implantation into 6H-SiC single crystal are presented. By following the recoils trajectories during the implantation simulation it is possible to construct C and Si related point defects distributions, which in turns give the post implantation stoichiometry of the SiC crystal. The results show net concentrations of ``stable`` point defects and stoichiometric disturbances of the order of the chemical concentration of the implanted impurity. This phenomenon could play an important role during subsequent annealing steps. Some practical examples of ion implantation are simulated and discussed. (orig.) 4 refs.

  17. TEMPOROMANDIBULAR-JOINT OSTEOARTHROSIS AND GENERALIZED JOINT HYPERMOBILITY

    NARCIS (Netherlands)

    DIJKSTRA, PU; DEBONT, LGM; STEGENGA, B; BOERING, G

    1992-01-01

    Peripheral joint mobility of temporomandibular joint (TMJ) osteoarthrosis and internal derangement patients (n = 25) and of a control group (n = 29) was measured according to a rigidly standardized protocol, in order to study the relationships between TMJ osteoarthrosis and internal derangement and

  18. Index of Joint Condition for PVC push-fit joints

    NARCIS (Netherlands)

    Arsenio, A.M.; Vreeburg, J.H.G.; Rietveld, L.

    2014-01-01

    The Index of Joint Condition (IJC) for polyvinyl chloride (PVC) push-fit joints, discussed in this article, was derived from installation guidelines and from destructive laboratory tests. The IJC is presented in a graphical framework and is a powerful tool to employ in order to visualize and compare

  19. Long-term bone tissue reaction to polyethylene oxide/polybutylene terephthalate copolymer (Polyactive) in metacarpophalangeal joint reconstruction.

    Science.gov (United States)

    Waris, Eero; Ashammakhi, Nureddin; Lehtimäki, Mauri; Tulamo, Riitta-Mari; Törmälä, Pertti; Kellomäki, Minna; Konttinen, Yrjö T

    2008-06-01

    The poly-L/D-lactide 96/4 joint scaffolds are used to engineer fibrous tissue joints in situ for the reconstruction of metacarpophalangeal joints. In this experimental study, a supplementary elastomeric stem made of Polyactive 1000PEO70PBT30 (a segmented block copolymer of polyethylene oxide and polybutylene terephtalate with 70/30 PEO/PBT ratio) was used to anchor the joint scaffold in the arthroplasty space. Eleven resected fifth metacarpophalangeal joints of minipig were reconstructed and evaluated radiologically and histologically for 3 years. Plain joint scaffold and Swanson silicone implant arthroplasties (11 of each) in metacarpophalangeal joints of minipig served as controls. Altogether fore limbs of eighteen minipigs were operated for the study. Deleterious tissue reaction with dramatic signs of osteolysis and inflammatory foreign-body reaction was observed around the Polyactive stems. The mean maximum diameter of the osteolytic stem cavity was statistically wider when compared to the mean maximum diameter of Swanson implant group during the first postoperative year. Numerous osteoclasts were found at the margins of the osteolytic areas. No direct bone contact could be seen. At 1 year osteoblastic regeneration and formation of new trabecular bone followed. Finally the foreign-body reaction settled, but the adjoining bones were at this stage highly sclerotic and composed of coarse trabeculae. In contrary to previous in vivo studies suggesting biocompatibility, osteoconductivity and capability to bond to bone, Polyactive 1000PEO70PBT30 stem in this setting caused massive osteolytic lesions and foreign-body reactions. PMID:18336902

  20. Temporomandibular joint arthrography

    International Nuclear Information System (INIS)

    The stress and occlusion disturbance are very important etiologic factors in the temporomandibular joint (TMJ) pain dysfunction syndromes. Authors performed TMJ arthrograms in the patients with TMJ problem such as pain, click sound, limited motion and locking, etc. The following results noted: 1. The arthrographic findings of 22 TMJ were analyzed. a) Normal: 6 cases b) Anterior disc displacement with rediction: 6 cases · Early reduction: 2 cases · Intermediate reduction: 3 cases · Late reduction: 1 case c) Anterior disc displacement without reduction: 6 cases · Two cases had adhesion between the posterior portion of disc and the posterior surfaces of the articular eminence. 2. Among 22 cases, the clinical findings of 16 cases (73%) were compatible with arthrographic findings. 6 cases showed disparity between them.

  1. Magnetic resonance imaging of breast implants.

    Science.gov (United States)

    Shah, Mala; Tanna, Neil; Margolies, Laurie

    2014-12-01

    Silicone breast implants have significantly evolved since their introduction half a century ago, yet implant rupture remains a common and expected complication, especially in patients with earlier-generation implants. Magnetic resonance imaging is the primary modality for assessing the integrity of silicone implants and has excellent sensitivity and specificity, and the Food and Drug Administration currently recommends periodic magnetic resonance imaging screening for silent silicone breast implant rupture. Familiarity with the types of silicone implants and potential complications is essential for the radiologist. Signs of intracapsular rupture include the noose, droplet, subcapsular line, and linguine signs. Signs of extracapsular rupture include herniation of silicone with a capsular defect and extruded silicone material. Specific sequences including water and silicone suppression are essential for distinguishing rupture from other pathologies and artifacts. Magnetic resonance imaging provides valuable information about the integrity of silicone implants and associated complications.

  2. [Metal implant sensitivity: clinical and histological presentation].

    Science.gov (United States)

    Hartmann, D; Letulé, V; Schneider, J J; Flaig, M J

    2016-05-01

    Metal implant sensitivity (intolerance) can cause pain, reduced mobility, loosening of the implant and skin rashes. Knowledge of differential diagnoses, histology and appropriate diagnostics are essential for proper diagnosis. To outline typical clinical signs and histology in metal-implant-associated skin lesions we present three exemplary patients from our implant allergy outpatient department and give an overview of the current literature regarding metal implant sensitivity. In patients with a negative patch test the lymphocyte transformation test may reveal metal sensitization. Even "pure" titanium alloys may contain traces of nickel. The histology of implant-associated skin reactions goes from teleangiectatic postimplantation erythema to eczema and vasculitis. Based on the synopsis of history, clinical picture, allergological testing and histology, metal implant sensitivity can be diagnosed more precisely. PMID:27090521

  3. Implant failure: regional versus cumulative evaluation.

    Science.gov (United States)

    Lauc, T; Krnić, D; Katanec, D

    2000-07-01

    In this paper the success rate of implant therapy in various bone regions is discussed. The objective is to determine whether differences existed in success rates of cylinder implants placed in different areas in the both maxilla and mandible. Forty four patients have been treated and reviewed five years after the placement of the fixed prosthetic restoration. The patients were provided with a total of 92 implants. Results from this study show very low survival rate for implants placed in anterior region of maxilla (55.6%) after five years. It is concluded that simple cumulative follow up studies do not entirely correspond to actual situations, positioning the implants has an important role in the planning of the implant therapy and that important factor for force compensation is not only the surrounding bone density, but also the region of the jaw where the implants are placed. PMID:10946471

  4. Implant fractures: Rare but not exceptional

    Directory of Open Access Journals (Sweden)

    Sahitya Sanivarapu

    2016-01-01

    Full Text Available Fabrication of dentures aided with implants has become a preferred treatment option for rehabilitation of completely and partially edentulous patients when durability is concerned. Simulation to natural teeth in terms of esthetics and to a greater extent in function can be considered as key elements in the raise of implant dentistry worldwide. Despite its high success rate, therapy with osseointegrated dental implants is not free of complications. Implant failure can occur for other reasons, with implant fracture being one of the major reasons for late failure. Although the incidence of implant fractures may be low, it invariably effects the patient and also clinician. Thus, sound evidence based knowledge of cause of fracture is mandatory for that careful treatment that can reduce the incidence of fracture helping in a better treatment plan. The aim of this review is to enlighten the various causes of implant fracture.

  5. Implant fractures: Rare but not exceptional.

    Science.gov (United States)

    Sanivarapu, Sahitya; Moogla, Srinivas; Kuntcham, Rupa Sruthi; Kolaparthy, Lakshmi Kanth

    2016-01-01

    Fabrication of dentures aided with implants has become a preferred treatment option for rehabilitation of completely and partially edentulous patients when durability is concerned. Simulation to natural teeth in terms of esthetics and to a greater extent in function can be considered as key elements in the raise of implant dentistry worldwide. Despite its high success rate, therapy with osseointegrated dental implants is not free of complications. Implant failure can occur for other reasons, with implant fracture being one of the major reasons for late failure. Although the incidence of implant fractures may be low, it invariably effects the patient and also clinician. Thus, sound evidence based knowledge of cause of fracture is mandatory for that careful treatment that can reduce the incidence of fracture helping in a better treatment plan. The aim of this review is to enlighten the various causes of implant fracture. PMID:27041830

  6. Surface characterization of titanium based dental implants

    International Nuclear Information System (INIS)

    Dental implantology uses metallic devices made of commercially pure titanium in order to replace lost teeth. Titanium presents favorable characteristics as bio material and modern implants are capable of integrate, witch is the union between bone and implant without fibrous tissue development. Three of the major Brazilian implant manufacturers were chosen to join the study. A foreign manufacturer participated as standard. The manufacturers had three specimens of each implant with two different surface finishing, as machined and porous, submitted to analysis. Surface chemical composition and implant morphology were analyzed by X-ray photoelectron spectroscopy (XP S), scanning electron microscopy (SEM) and microprobe. Implant surface is mainly composed of titanium, oxygen and carbon. Few contaminants commonly present on implant surface were found on samples. Superficial oxide layer is basically composed of titanium dioxide (TiO2), another oxides as Ti O and Ti2O3 were also found in small amount. Carbon on implant surface was attributed to manufacturing process. Nitrogen, Phosphorous and Silicon appeared in smaller concentration on surface. There was no surface discrepancy among foreign and Brazilian made implants. SEM images were made on different magnification, 35 X to 3500 X, and showed similarity among as machined implants. Porous surface finishing implants presented distinct morphology. This result was attributed to differences on manufacturing process. Implant bioactivity was accessed through immersion on simulated body solution (SBF) in order to verify formation of an hydroxyapatite (HA) layer on surface. Samples were divided on three groups according to immersion time: G1 (7 days), G2 (14 days), G3 (21 days), and deep in SBF solution at 37 deg C. After being removed from solution, XPS analyses were made and then implants have been submitted to microprobe analysis. XPS showed some components of SBF solution on sample surface but microprobe examinations did not

  7. [Evaluation of asymetric implants in breast cancer].

    Science.gov (United States)

    Fitoussi, A; Couturaud, B; Laki, F; Alran, S; Salmon, R J

    2005-10-01

    Since more than twenty years, methods of breast reconstruction using implants have continued to evolve in order to improve their aesthetic results. Shapes and materials of these implants have also evolved to obtain contours similar to that of the natural opposite breast. Therefore it can be considered that the use of asymmetric implants is the last step in implant technology before using made to measure implants. Asymmetric implants allow obtaining different contours in harmony to the different breast shapes according to the side, left or right, of the reconstructed breast which maximise the naturalness of the result. Such implants have an axis directed towards the exterior and lower part of the chest wall, are wider than high with a thinner part on their inner edge and a concave rear side moulding the curves of the chest wall. In our own experience, we placed more than 500 asymmetric implants. When analysing retrospectively the medical records of 156 patients, no distinctive features were observed when compared to symmetric classic implants in easiness in the surgical procedure or in complications except a slightly higher rate of seroma formation. When compared to usual implants the main benefits of asymmetric implants are: to offer a wider breadth, to slope down gently on their upper and inner sides according to their concave rear side, and therefore to better match subtle curves of a normal breast. Moreover such contours allow a distribution of the volume which fit better to the usual natural breast configuration of patients who underwent surgery for breast carcinoma. At last, such implants are easy to place and a very low rate of secondary rotation has been observed. In summary, for all these reasons, asymmetric implants, can be considered to be the class one in the choice of implants for breast reconstruction after breast surgery. PMID:16198040

  8. Effects of Delayed Second Cochlear Implant

    Institute of Scientific and Technical Information of China (English)

    XIA Rui-ming; WU Xi-hong; JANG Zi-gang; JING Yuan-yuan; LIN Yun-juan; YU Li-sheng

    2006-01-01

    Objective Since Helms' successful bilateral cochlear implantation with good results in 1996, there have been increasing number of reports on bilateral cochlear implantation. Most second device have been implantated within one year after the first. Considering effects of long time auditory deprivation, it is not clear whether a delayed second cochlear implant serves to add additional benefits and how it may interact with central nervous system plasticity. Methods Three cases who received delayed second cochlear implants at People's Hospital of Peking University from 2002 to 2005 were reviewed. The interval between the first and second implants was longer than 2 years in all three patients. Sound perception, and unilateral/bilateral speech discrimination in quiet and noise were evaluated. In addition, GAP detection test was conducted in one patient. Results In one case,having both implants on provided improved performance compared to using only one implant both in quiet and noise. Presumably due to visual interference from lip-reading or short interval between second implant and testing,one patient showed no improvement from using the second implant either in quiet or noise, while the last case demonstrated additional benefits from the second implant only in quiet. In all three patients, performance in recognizing the four tones in Mandarin was superior over word recognition. Conclusions Considerable plasticity in the cerebral auditory center is preserved, despite long acoustic deprivation in some children who have received unilateral cochlear implant. Delayed second implants can result in significant improvements in some of these children. Visual interference from lip-reading may be an obstacle during retraining. The better recognition of tones in the Mandarin language may represent a different sound discrimination mechanism in the auditory system,although it may also be related to the signal processing mechanisms of the implant used (MED-EL COMBI 40+).

  9. Mini vs. Standard Implants for Mandibular Overdentures: A Randomized Trial.

    Science.gov (United States)

    de Souza, R F; Ribeiro, A B; Della Vecchia, M P; Costa, L; Cunha, T R; Reis, A C; Albuquerque, R F

    2015-10-01

    A mandibular implant-retained overdenture is considered a first-choice treatment for edentulism. However, some aspects limit the use of standard implants-for example, the width of edentulous ridges, chronic diseases, fear, or costs. This randomized trial compared mandibular overdentures retained by 2 or 4 mini-implants with standard implants, considering oral health-related quality of life (OHRQoL), patient satisfaction, and complications such as lost implant. In sum, 120 edentulous men and women (mean age, 59.5 ± 8.5 y) randomly received 4 mini-implants, 2 mini-implants, or 2 standard implants. Participants provided data regarding OHRQoL and satisfaction until 12 mo. Clinical parameters, including implant survival rate, were also recorded. Both 2 and 4 mini-implants led to better OHRQoL, compared with 2 standard implants. Treatment with 4 mini-implants was more satisfying than 2 standard implants, with 2 mini-implants presenting intermediate results. Implant survival rate was 89%, 82%, and 99% for 4 mini-implants, 2 mini-implants, or 2 standard implants, respectively. Overdentures retained by 4 or 2 mini-implants can achieve OHRQoL and satisfaction at least comparable with that of 2 standard implants. However, the survival rate of mini implants is not as high as that of standard implants (ClinicalTrials.gov NCT01411683). PMID:26294416

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

    Directory of Open Access Journals (Sweden)

    Matteo Danza

    2014-01-01

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

  11. Factors influencing success of cement versus screw-retained implant restorations: a clinical review

    Directory of Open Access Journals (Sweden)

    Ahmad Manawar

    2012-10-01

    Full Text Available Aim: As more and more dental practitioners are focusing on implant-supported fixed restorations, some clinicians favor the use of cement retained restorations while others consider screw retained prosthesis to be the best choice. Discussion: In screw-retained restorations, the fastening screw provides a solid joint between the restoration and the implant abutment, while in cement-retained prostheses the restorative screw is eliminated to enhance esthetics, occlusal stability, and passive fit of the restorations. The factors that influence the type of fixation of the prostheses to the implants like passivity of the framework, ease of fabrication, occlusion, esthetics, accessibility, retention and retrievability are discussed in this article with scientific studies demonstrating superior outcomes of one technique over another. Screwretained implant restorations have an advantage of predictable retention, retrievability and lack of potentially retained subgingival cement. However, a few disadvantages exist such as precise placement of the implant for optimal and esthetic location of the screw access hole and obtaining passive fit. On the other hand, cement retained restorations eliminate unesthetic screw access holes, have passive fit of castings, reduced complexity of clinical and lab procedures, enhanced esthetics, reduced cost factors and non disrupted morphology of the occlusal table. Conclusion: This article compares the advantages, potential disadvantages and limitations of screw and cement retained restorations and their specific implications in the most common clinical situation.

  12. Saving Joint with Aerosol physics

    International Nuclear Information System (INIS)

    Full text: Using electro spray method to analyze wear debris from artificial joints. Well known aerosol techniques have been applied to determine the size distribution and concentration of wear particles found in joint fluids. The organic fraction (cells and large molecules) are removed by digestion. Knowing these data the risk of clogging of blood vessels can be medicinally reduced. (author)

  13. Structuring managed care joint ventures.

    Science.gov (United States)

    Williams, L

    1995-08-01

    Providers that undertake joint ventures to secure managed care contracts must understand the important governance, operational, legal, and political issues involved. Careful planning in all these areas can help ensure that the joint venture will meet its goals and avoid problems such as inappropriately negotiated contracts and legal violations.

  14. 37 CFR 1.45 - Joint inventors.

    Science.gov (United States)

    2010-07-01

    ... 37 Patents, Trademarks, and Copyrights 1 2010-07-01 2010-07-01 false Joint inventors. 1.45 Section... Patent § 1.45 Joint inventors. (a) Joint inventors must apply for a patent jointly and each must make the... patent for an invention invented by them jointly, except as provided in § 1.47. (b) Inventors may...

  15. Detection and identification of microbes in prosthetic joint infections by culture and molecular methods

    DEFF Research Database (Denmark)

    Xu, Yijuan; Schønheyder, Henrik Carl; Ehrlich, Garth;

    used for analysis, particularly prosthetic implants yielded more positive results. Furthermore, the presence of bacteria as both single cells and microcolonies were visualized by fluorescence in situ hybridization using peptide nucleic acid and DNA probes and confocal scanning laser microscopy......, indicating biofilm formation. In conclusion, this study indicated that to improve the microbiological diagnosis of prosthetic joint infections molecular methods may be useful supplements to routine cultures, and the current intraoperative sampling strategy needs to be optimized....

  16. Ambulatory estimation of knee-joint kinematics in anatomical coordinate system using accelerometers and magnetometers.

    Science.gov (United States)

    Kun, Liu; Inoue, Yoshio; Shibata, Kyoko; Enguo, Cao

    2011-02-01

    Knee-joint kinematics analysis using an optimal sensor set and a reliable algorithm would be useful in the gait analysis. An original approach for ambulatory estimation of knee-joint angles in anatomical coordinate system is presented, which is composed of a physical-sensor-difference-based algorithm and virtual-sensor-difference-based algorithm. To test the approach, a wearable monitoring system composed of accelerometers and magnetometers was developed and evaluated on lower limb. The flexion/extension (f/e), abduction/adduction (a/a), and inversion/extension (i/e) rotation angles of the knee joint in the anatomical joint coordinate system were estimated. In this method, since there is no integration of angular acceleration or angular velocity, the result is not distorted by offset and drift. The three knee-joint angles within the anatomical coordinate system are independent of the orders, which must be considered when Euler angles are used. Besides, since there are no physical sensors implanted in the knee joint based on the virtual-sensor-difference-based algorithm, it is feasible to analyze knee-joint kinematics with less numbers and types of sensors than those mentioned in some others methods. Compared with results from the reference system, the developed wearable sensor system is available to do gait analysis with fewer sensors and high degree of accuracy.

  17. [Implantation of the artificial retina].

    Science.gov (United States)

    Yagi, T; Hayashida, Y

    1999-05-01

    In some degenerative retinal diseases, e.g., retinitis pigmentosa and age-related macular degeneration, the photoreceptors are destroyed to cause serious visual defects. Recent studies on blind human subjects revealed that a large number of ganglion cells remains intact and is capable of transmitting signals to the brain to evoke partial visual perception. This provided hope to compensate for the visual defects with retinal prostheses. The recent progress of microfabrication technique made it possible to implement the Vary Large Scale Integrated circuit, the artificial retina, which emulates a part of retinal function. The idea of implanting the artificial retina to the patients was proposed recently and experiments using animals have been put into practice. This article surveys the front line of the artificial retina implantation.

  18. Surrogate Modeling of Deformable Joint Contact using Artificial Neural Networks

    Science.gov (United States)

    Eskinazi, Ilan; Fregly, Benjamin J.

    2016-01-01

    Deformable joint contact models can be used to estimate loading conditions for cartilage-cartilage, implant-implant, human-orthotic, and foot-ground interactions. However, contact evaluations are often so expensive computationally that they can be prohibitive for simulations or optimizations requiring thousands or even millions of contact evaluations. To overcome this limitation, we developed a novel surrogate contact modeling method based on artificial neural networks (ANNs). The method uses special sampling techniques to gather input-output data points from an original (slow) contact model in multiple domains of input space, where each domain represents a different physical situation likely to be encountered. For each contact force and torque output by the original contact model, a multi-layer feed-forward ANN is defined, trained, and incorporated into a surrogate contact model. As an evaluation problem, we created an ANN-based surrogate contact model of an artificial tibiofemoral joint using over 75,000 evaluations of a fine-grid elastic foundation (EF) contact model. The surrogate contact model computed contact forces and torques about 1000 times faster than a less accurate coarse grid EF contact model. Furthermore, the surrogate contact model was seven times more accurate than the coarse grid EF contact model within the input domain of a walking motion. For larger input domains, the surrogate contact model showed the expected trend of increasing error with increasing domain size. In addition, the surrogate contact model was able to identify out-of-contact situations with high accuracy. Computational contact models created using our proposed ANN approach may remove an important computational bottleneck from musculoskeletal simulations or optimizations incorporating deformable joint contact models. PMID:26220591

  19. Design of an implantable micropump

    OpenAIRE

    Smal, Olivier; Merken, Patrick; Croquet, Vincent; Raucent, Benoît; Debongnie, Jean-François; Delchambre, Alain

    2004-01-01

    The implantable programmable micropump is an interesting solution to treat chronic diseases such as diabetes with regular micro-injections of medicine. However, current applications of micropumps are limited by their rather expensive cost. The challenge is therefore to develop a low cost alternative by reducing the number of parts and by simplifying the assembly. As the pump and its tank will be placed under the skin in order to increase comfort, such a system should be small and reliable. In...

  20. Developmental Neuroplasticity After Cochlear Implantation

    OpenAIRE

    Kral, Andrej; Sharma, Anu

    2011-01-01

    Cortical development is dependent on stimulus-driven learning. The absence of sensory input from birth, as occurs in congenital deafness, affects normal growth and connectivity needed to form a functional sensory system—resulting in deficits in oral language learning. Cochlear implants bypass cochlear damage by directly stimulating the auditory nerve and brain, making it possible to avoid many of the deleterious effects of sensory deprivation. Congenitally deaf animals and children who receiv...

  1. Magnesium as Biodegradable Implant Material

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Drawbacks associated with permanent metallic implants lead to the search for degradable metallic biomaterials. Magnesium alloys have been highly considered as Mg has a high biocorrosion potential and is essential to bodies. In this study, corrosion behaviour of pure magnesium and magnesium alloy AZ31 in both static and dynamic physiological conditions (Hank's solution) has been investigated. It is found that the materials degrade fast at beginning, then stabilize after 5 days of immersion. High purity in th...

  2. Implantable telemetry for small animals

    Science.gov (United States)

    1982-03-01

    A series of totally implantable telemetry devices for use in measuring deep body parameters in small animals were developed. Under a collaborative agreement with NASA, several of these systems; the continuous wave Doppler ultrasonic flowmeter, the multichannel telemetry system, and the inductively-powered dual channel cardiac pacer were evaluated in a series of ten mongrel dogs (15 to 20 kg.). These systems were used to measure ascending aortic and coronary blood flow, aortic pressure, and subcutaneous EKG.

  3. Treatment of protruding osseo integrated dental implant

    Directory of Open Access Journals (Sweden)

    Buddula Aravind

    2010-01-01

    Full Text Available Titanium dental implants have been used in the treatment of partial or complete edentulism. The height and width of the residual alveolus and surrounding anatomical structures can determine the proper position and path of insertion of dental implants. The following case report describes the treatment of a malpositioned osseo integrated dental implant with an apex perforating the buccal cortex of alveolar bone. A 61-year-old male was referred by his local dentist for the chief complaint of a swelling at site of tooth 14 where an implant was present. Intraoral clinical examination revealed an implant supported porcelain fused to metal crown replacing the maxillary right first premolar. A peri-apical radiograph of the implant revealed no signs of peri-implant bone loss or radiolucency. Surgical exploration and modification of the protruding implant. The area healed uneventfully without the need of explantation of the implant in site of tooth 14. We felt that the conservative treatment provided was prudent and treatment of choice and anticipate that the implant will most likely continue to function for a lifetime.

  4. Simvastatin Reduces Capsular Fibrosis around Silicone Implants.

    Science.gov (United States)

    Chung, Kyu Jin; Park, Ki Rin; Lee, Jun Ho; Kim, Tae Gon; Kim, Yong-Ha

    2016-08-01

    Capsular fibrosis and contracture occurs in most breast reconstruction patients who undergo radiotherapy, and there is no definitive solution for its prevention. Simvastatin was effective at reducing fibrosis in various models. Peri-implant capsular formation is the result of tissue fibrosis development in irradiated breasts. The purpose of this study was to examine the effect of simvastatin on peri-implant fibrosis in rats. Eighteen male Sprague-Dawley rats were allocated to an experimental group (9 rats, 18 implants) or a control group (9 rats, 18 implants). Two hemispherical silicone implants, 10 mm in diameter, were inserted in subpanniculus pockets in each rat. The next day, 10-Gy of radiation from a clinical accelerator was targeted at the implants. Simvastatin (15 mg/kg/day) was administered by oral gavage in the experimental group, while animals in the control group received water. At 12 weeks post-implantation, peri-implant capsules were harvested and examined histologically and by real-time polymerase chain reaction. The average capsular thickness was 371.2 μm in the simvastatin group and 491.2 μm in the control group. The fibrosis ratio was significantly different, with 32.33% in the simvastatin group and 58.44% in the control group (P silicone implants in rats. This finding offers an alternative therapeutic strategy for reducing capsular fibrosis and contracture after implant-based breast reconstruction. PMID:27478339

  5. Computerized implant-dentistry: Advances toward automation

    Directory of Open Access Journals (Sweden)

    Minkle Gulati

    2015-01-01

    Full Text Available Advancements in the field of implantology such as three-dimensional imaging, implant-planning software, computer-aided-design/computer-aided-manufacturing (CAD/CAM technology, computer-guided, and navigated implant surgery have led to the computerization of implant-dentistry. This three-dimensional computer-generated implant-planning and surgery has not only enabled accurate preoperative evaluation of the anatomic limitations but has also facilitated preoperative planning of implant positions along with virtual implant placement and subsequently transferring the virtual treatment plans onto the surgical phase via static (guided or dynamic (navigated systems aided by CAD/CAM technology. Computerized-implant-dentistry being highly predictable and minimally invasive in nature has also allowed implant placement in patients with medical comorbidities (e.g. radiation therapy, blood dyscrasias, in patients with complex problems following a significant alteration of the bony anatomy as a result of benign or malignant pathology of the jaws or trauma and in patients with other physical and emotional problems. With significant achievements accomplished in the field of computerized implant-dentistry, attempts are now been made toward complete automation of implant-dentistry.

  6. Exposed Dental Implant? Local Autograft A Saviour!

    Science.gov (United States)

    Rai, Raj; Punde, Prashant A; Suryavanshi, Harshal; Shree, Swetha

    2015-01-01

    Implant exposure due to faulty placement, posses as the most common reason for implant failure. The implant placed too close to buccal or lingual cortex have lead to such failure on numerous occasions. Also, anatomic variations like the thin buccolingual width of alveolar ridge predispose exposure of the implant. 25-year-old female patient had undergone surgical placement of implants in mandibular anterior region 2 months back in the private dental clinic. The clinician noted Grade I mobility in one of the implants placed. The case was referred to the author. Thin overlying gingiva depicted an entire buccal aspect of the implant, which suggested more than 90 % loss of buccal cortex. According to literature and review of similar case reports, the only way suggested was to surgically remove the implant and wait for 12-24 months for the bone to heal for subsequent placement. Rather than the removal of implants as suggested, the author followed a naval approach of reinforcing buccal cortex using an autogenous cortical block from mandibular symphysis. The reinforcement surgery had certainly saved patients time, money and most importantly limits a crucial period of edentulism, which may be enforced on a patient in case the implant was removed. PMID:26668490

  7. General joint hypermobility and temporomandibular joint derangement in adolescents.

    OpenAIRE

    Westling, L; Mattiasson, A.

    1992-01-01

    Joint mobility was assessed in each member of an epidemiological sample of 96 girls and 97 boys, 17 years old, and graded by means of the hypermobility score of Beighton et al. Twenty two per cent of the girls and 3% of the boys could perform five or more of the nine manoeuvres. The prevalence of symptoms and signs of internal derangement in the temporomandibular joint was higher in adolescents with hypermobility of joints (score greater than or equal to 5/9). In subjects with a high mobility...

  8. Cortical Plasticity after Cochlear Implantation

    Directory of Open Access Journals (Sweden)

    B. Petersen

    2013-01-01

    tomography at three time points: within 14 days, three months, and six months after switch-on. Fifteen recently implanted adult implant recipients listened to running speech or speech-like noise in four sequential PET sessions at each milestone. CI listeners with postlingual hearing loss showed differential activation of left superior temporal gyrus during speech and speech-like stimuli, unlike CI listeners with prelingual hearing loss. Furthermore, Broca’s area was activated as an effect of time, but only in CI listeners with postlingual hearing loss. The study demonstrates that adaptation to the cochlear implant is highly related to the history of hearing loss. Speech processing in patients whose hearing loss occurred after the acquisition of language involves brain areas associated with speech comprehension, which is not the case for patients whose hearing loss occurred before the acquisition of language. Finally, the findings confirm the key role of Broca’s area in restoration of speech perception, but only in individuals in whom Broca’s area has been active prior to the loss of hearing.

  9. Miniaturized neural interfaces and implants

    Science.gov (United States)

    Stieglitz, Thomas; Boretius, Tim; Ordonez, Juan; Hassler, Christina; Henle, Christian; Meier, Wolfgang; Plachta, Dennis T. T.; Schuettler, Martin

    2012-03-01

    Neural prostheses are technical systems that interface nerves to treat the symptoms of neurological diseases and to restore sensory of motor functions of the body. Success stories have been written with the cochlear implant to restore hearing, with spinal cord stimulators to treat chronic pain as well as urge incontinence, and with deep brain stimulators in patients suffering from Parkinson's disease. Highly complex neural implants for novel medical applications can be miniaturized either by means of precision mechanics technologies using known and established materials for electrodes, cables, and hermetic packages or by applying microsystems technologies. Examples for both approaches will be introduced and discussed. Electrode arrays for recording of electrocorticograms during presurgical epilepsy diagnosis have been manufactured using approved materials and a marking laser to achieve an integration density that is adequate in the context of brain machine interfaces, e.g. on the motor cortex. Microtechnologies have to be used for further miniaturization to develop polymer-based flexible and light weighted electrode arrays to interface the peripheral and central nervous system. Polyimide as substrate and insulation material will be discussed as well as several application examples for nerve interfaces like cuffs, filament like electrodes and large arrays for subdural implantation.

  10. Ion implanted pyrolitic carbon for the hip prosthesis

    International Nuclear Information System (INIS)

    Full text: Hip joint arthroplasty is a successful surgical procedure, but loosening induced by polyethylene wear debris continues to be a problem. Fine grained isotropic graphite (POCO ZXF-5Q) coated with Pyrolite (trademark of Carbomedics Inc.) combines biocompatibility, strength and tribological properties which could be utilised in a hip prosthesis. Some preliminary work has been conducted on this material, and the effect nitrogen ion implantation has on its wear resistance. Finite element analysis was conducted on a femoral head of a canine hip prosthesis with diameter 19mm made from POCO ZXF-5Q . An optimum design was obtained after design variables such as taper angle and width, internal recess radius, crown thickness were varied so that internal stresses were minimised. This was then translated into an human sized femoral head with diameter 28mm, which was subjected to mechanical testing. Loading was at 20 deg C to the taper, with loading rate 10kN/s used in static loading, whilst fatigue testing was carried out between 300 - 3000N at 30Hz for 107 cycles. Pin-on-disc wear testing was carried out using a CSEM Tribometer. A 1N load was applied to 6mm diameter pins. Wear track radii were 11 and 13mm, with linear velocity 5cm/s and sliding distance 2.5km. Test temperature was 37±1degC with Ringer solution and bovine serum being used as lubricant. Nitrogen implanted samples were irradiated to a dose of 5x1016 ions.cm-2 at 50keV. Static testing was carried out to loads of 8000N and all five POCO ZXF-5Q femoral heads tested survived. Then three of these pre-tested femoral heads were subjected to fatigue testing and no failures occured before 107 cycles. Wear was reduced by nitrogen ion implantation only when an irradiated pin was tested against as polished Pyrolite. Nitrogen ion implanted Pyrolite on a POCO ZXF-5Q substrate may have clinical potential. The substrate has appropriate mechanical properties, and nitrogen ion implantation can improve the already

  11. In Vivo Assessment of Phage and Linezolid Based Implant Coatings for Treatment of Methicillin Resistant S. aureus (MRSA) Mediated Orthopaedic Device Related Infections

    Science.gov (United States)

    Kaur, Sandeep; Harjai, Kusum; Chhibber, Sanjay

    2016-01-01

    Staphylococcus comprises up to two-thirds of all pathogens in orthopaedic implant infections with two species respectively Staphylococcus aureus and Staphylococcus epidermidis, being the predominate etiological agents isolated. Further, with the emergence of methicillin-resistant S. aureus (MRSA), treatment of S. aureus implant infections has become more difficult, thus representing a devastating complication. Use of local delivery system consisting of S.aureus specific phage along with linezolid (incorporated in biopolymer) allowing gradual release of the two agents at the implant site represents a new, still unexplored treatment option (against orthopaedic implant infections) that has been studied in an animal model of prosthetic joint infection. Naked wire, hydroxypropyl methylcellulose (HPMC) coated wire and phage and /or linezolid coated K-wire were surgically implanted into the intra-medullary canal of mouse femur bone of respective groups followed by inoculation of S.aureus ATCC 43300(MRSA). Mice implanted with K-wire coated with both the agents i.e phage as well as linezolid (dual coated wires) showed maximum reduction in bacterial adherence, associated inflammation of the joint as well as faster resumption of locomotion and motor function of the limb. Also, all the coating treatments showed no emergence of resistant mutants. Use of dual coated implants incorporating lytic phage (capable of self-multiplication) as well as linezolid presents an attractive and aggressive early approach in preventing as well as treating implant associated infections caused by methicillin resistant S. aureus strains as assessed in a murine model of experimental joint infection. PMID:27333300

  12. 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.

  13. He reemission implanted in metals

    Energy Technology Data Exchange (ETDEWEB)

    Tanabe, T., E-mail: tanabe@nucl.kyushu-u.ac.jp

    2014-10-15

    Highlights: • Observation of He reemission of various metals under He{sup +} implantation at wide temperature range. • Materials examined are aluminum (Al), Nickel (Ni) and molybdenum (Mo). • He reemission is quite temperature dependent and different with materials. • Three metals show similar dependence on temperature normalized with respective melting point. • He reemission is successfully correlated with He behavior in metals. - Abstract: Helium (He) reemission of Al, Ni and Mo under energetic He implantation (10–30 keV) in wide temperature range is studied to understand behavior of implanted He in correlation with structure changes. The reemission behavior is categorized into 4 different temperature ranges with the normalized temperature (T{sub m}) to the melting point of each metal. At elevated temperatures (well above ∼0.6 T{sub m}), interstitial He atoms and/or He-vacancy (ies) clusters can migrate remaining no structure change and showing smooth reemission without any burst. Between ∼0.25 and 0.6 T{sub m}, He reemission always accompanies significant structure modification. For ∼04–0.6 T{sub m}, implanted He coalesce to make bubbles and the bubbles can move to the surface. Bubble migration accompanies materials flow to the surface resulting in fuzz surface or columnar structure, depending on implantation flux. Slower bubble motion at ∼0.25–0.4 prohibits the material migration. Instead the bubbles coalesce to grow large and multi-layered blistering appears as periodic reemission behavior. Below ∼0.25 T{sub m}, He migration is too slow for bubbles to grow large, but bubble density increases up to a certain fluence, where neighboring bubbles start to coalesce. Accordingly, He release is mostly caused by mechanical failure or blister rapture. With increasing fluence, all defects (bubbles and dislocation loops) tangle or inter connected with neighboring defects and accordingly He migration to the surface along the tangled or connected

  14. TEMPOROMANDIBULAR-JOINT OSTEOARTHROSIS AND TEMPOROMANDIBULAR-JOINT HYPERMOBILITY

    NARCIS (Netherlands)

    DIJKSTRA, PU; DEBONT, LGM; DELEEUW, R; STEGENGA, B; BOERING, G

    1993-01-01

    For studying the relationship between condylar hypermobility of the temporomandibular joint (TMJ) and osteoarthrosis (OA), 13 patients with bilateral condylar hypermobility were evaluated clinically and radiographically, 30 years after non-surgical treatment. The evaluation included range of motion,

  15. Cochlear implantation and change in quality of life

    DEFF Research Database (Denmark)

    Faber, Christian; Grøntved, Ågot Møller

    2000-01-01

    The aim of this study was to assess the benefits of cochlear implantation (CI) in adults and to evaluate the average implant usage per day. Ten profoundly deaf adults were implanted during the period April 1994 to September 1997. The patients answered questionnaires 1 year or more after receiving...... their cochlear implants. All of the patients used their implant daily. The average implant usage per day was 16 h. The patients stated that, given the choice, they would again opt for a cochlear implant and would recommend a cochlear implant for a deaf friend. A paired comparison showed that the implants led...

  16. Joint ventures in health care.

    Science.gov (United States)

    Pelfrey, S; Theisen, B A

    1989-04-01

    To remain competitive, many not-for-profit hospitals have turned to joint ventures with for-profit and other not-for-profit entities. The authors examine the organizational structures that are used most often to form joint ventures (contractual agreements, subsidiary corporations, partnerships, and not-for-profit title-holding corporations), as well as the advantages and disadvantages associated with each form. Nurse executives must be aware of the opportunities that joint ventures provide their institutions. These arrangements can help improve and expand services and profitability.

  17. Early Loaded Single Implant Reinforced Mandibular Overdenture.

    Science.gov (United States)

    Nischal, K; Chowdhary, R

    2016-01-01

    Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. Midline fracture of the prosthesis is the most common complication related to single implant and two-implant retained mandibular overdentures. To manage such complication, a thin metal mesh is used to reinforce the overdenture and also to make the prostheses lighter and cost effective as compared to conventional cast metal framework. PMID:27403350

  18. Early Loaded Single Implant Reinforced Mandibular Overdenture

    Directory of Open Access Journals (Sweden)

    K. Nischal

    2016-01-01

    Full Text Available Rehabilitating atrophied mandible with two-implant supported denture is a common treatment modality for implant retained removable overdenture in mandible. This paper aims to design a treatment modality where single implant reinforced overdenture is fabricated for a severely atrophied mandibular ridge with early loading protocol. Results of studies have shown that a single implant mandibular overdenture significantly increases the satisfaction and quality of life of patients with edentulism. Midline fracture of the prosthesis is the most common complication related to single implant and two-implant retained mandibular overdentures. To manage such complication, a thin metal mesh is used to reinforce the overdenture and also to make the prostheses lighter and cost effective as compared to conventional cast metal framework.

  19. Common Prosthetic Implant Complications in Fixed Restorations.

    Science.gov (United States)

    Link-Bindo, Elyce E; Soltys, James; Donatelli, David; Cavanaugh, Richard

    2016-07-01

    Many clinicians consider implants to be one of the most important innovations in dental care. Even so, over the past 40 years of implant dentistry, complications have been a constant struggle for restorative dentists, surgeons, and patients alike. Implant-related problems can be particularly challenging and frustrating, especially given that an implant is thought to be a "lifetime" solution expected to yield minimal difficulties. This, however, is not necessarily the case with prosthetic restorations. With innovations in implant technology continuing to rapidly advance, maintaining knowledge of all the latest developments can be challenging for clinicians. The purpose of this article is to provide a basic understanding of the treatment, management, and prevention of common prosthetic and technical implant complications seen in the office of a restorative dentist. PMID:27548395

  20. Safety and 6-month effectiveness of minimally invasive sacroiliac joint fusion: a prospective study

    Directory of Open Access Journals (Sweden)

    Duhon BS

    2013-12-01

    Full Text Available Bradley S Duhon,1 Daniel J Cher,2 Kathryn D Wine,2 Harry Lockstadt,3 Don Kovalsky,4 Cheng-Lun Soo5On behalf of the SIFI Study Group1Neurosurgical and Spine Specialists, Parker, CO, 2SI-BONE, Inc, San Jose, CA, 3Bluegrass Orthopaedics and Hand Care, Lexington, KY, 4Orthopaedic Center of Southern Illinois, Mount Vernon, IL, 5Health Research Institute, Oklahoma City, OK, USABackground: Sacroiliac (SI joint pain is an often overlooked cause of low back pain. SI joint arthrodesis has been reported to relieve pain and improve quality of life in patients suffering from degeneration or disruption of the SI joint who have failed non-surgical care. We report herein early results of a multicenter prospective single-arm cohort of patients with SI joint degeneration or disruption who underwent minimally invasive fusion using the iFuse Implant System®.Methods: The safety cohort includes 94 subjects at 23 sites with chronic SI joint pain who met study eligibility criteria and underwent minimally invasive SI joint fusion with the iFuse Implant System® between August 2012 and September 2013. Subjects underwent structured assessments preoperatively, immediately postoperatively, and at 1, 3, and 6 months postoperatively, including SI joint and back pain visual analog scale (VAS, Oswestry Disability Index (ODI, Short Form-36 (SF-36, and EuroQoL-5D (EQ-5D. Patient satisfaction with surgery was assessed at 6 months. The effectiveness cohort includes the 32 subjects who have had 6-month follow-up to date.Results: Mean subject age was 51 years (n=94, safety cohort and 66% of patients were women. Subjects were highly debilitated at baseline (mean VAS pain score 78, mean ODI score 54. Three implants were used in 80% of patients; two patients underwent staged bilateral implants. Twenty-three adverse events occurred within 1 month of surgery and 29 additional events occurred between 30 days and latest follow-up. Six adverse events were severe but none were device

  1. Clinical management of implant prostheses in patients with bruxism

    NARCIS (Netherlands)

    O. Komiyama; F. Lobbezoo; A. de Laat; T. Iida; T. Kitagawa; H. Murakami; T. Kato; M. Kawara

    2012-01-01

    There is general agreement that excessive stress to the bone-implant interface may result in implant overload and failure. Early failure of the implant due to excessive loading occurs shortly after uncovering the implant. Excess load on a final restoration after successful implant integration can re

  2. Ion sources for energy extremes of ion implantation.

    Science.gov (United States)

    Hershcovitch, A; Johnson, B M; Batalin, V A; Kropachev, G N; Kuibeda, R P; Kulevoy, T V; Kolomiets, A A; Pershin, V I; Petrenko, S V; Rudskoy, I; Seleznev, D N; Bugaev, A S; Gushenets, V I; Litovko, I V; Oks, E M; Yushkov, G Yu; Masunov, E S; Polozov, S M; Poole, H J; Storozhenko, P A; Svarovski, A Ya

    2008-02-01

    For the past four years a joint research and development effort designed to develop steady state, intense ion sources has been in progress with the ultimate goal to develop ion sources and techniques that meet the two energy extreme range needs of meV and hundreads of eV ion implanters. This endeavor has already resulted in record steady state output currents of high charge state of antimony and phosphorus ions: P(2+) [8.6 pmA (particle milliampere)], P(3+) (1.9 pmA), and P(4+) (0.12 pmA) and 16.2, 7.6, 3.3, and 2.2 pmA of Sb(3+)Sb(4+), Sb(5+), and Sb(6+) respectively. For low energy ion implantation, our efforts involve molecular ions and a novel plasmaless/gasless deceleration method. To date, 1 emA (electrical milliampere) of positive decaborane ions was extracted at 10 keV and smaller currents of negative decaborane ions were also extracted. Additionally, boron current fraction of over 70% was extracted from a Bernas-Calutron ion source, which represents a factor of 3.5 improvement over currently employed ion sources.

  3. Wear Behavior of an Unstable Knee: Stabilization via Implant Design?

    Directory of Open Access Journals (Sweden)

    Jörn Reinders

    2014-01-01

    Full Text Available Background. Wear-related failures and instabilities are frequent failure mechanisms of total knee replacements. High-conforming designs may provide additional stability for the joint. This study analyzes the effects of a ligamentous insufficiency on the stability and the wear behavior of a high-conforming knee design. Methods. Two simulator wear tests were performed on a high-conforming total knee replacement design. In the first, a ligamentous-stable knee replacement with a sacrificed anterior cruciate ligament was simulated. In the second, a ligamentous-unstable knee with additionally insufficient posterior cruciate ligament and medial collateral ligament was simulated. Wear was determined gravimetrically and wear particles were analyzed. Implant kinematics was recorded during simulation. Results. Significantly higher wear rates (P≤0.001 were observed for the unstable knee (14.58±0.56 mg/106 cycles compared to the stable knee (7.97 ± 0.87 mg/106 cycles. A higher number of wear particles with only small differences in wear particle characteristics were observed. Under unstable knee conditions, kinematics increased significantly for translations and rotations (P≤0.01. This increase was mainly attributed to higher tibial posterior translation and internal rotations. Conclusion. Higher kinematics under unstable test conditions is a result of insufficient stabilization via implant design. Due to the higher kinematics, increased wear was observed in this study.

  4. Improving electric contacts by ion implantation

    Energy Technology Data Exchange (ETDEWEB)

    Xu Shiru; Zhang Ying; Zheng Tiampi

    1989-01-01

    This article studies the improvement of electric contacts by ion implantation. 1 x 10/sup 17/ cm/sup -2/ of N/sup +/ and N/sub 2//sup +/ was implanted into two kinds of electric contacts, then a make-and-break test was made with the low voltage electrical apparatus. The weight loss of the contacts, temperature rise, contact resistance and transfer of material between the two contacts were measured. The contacts implanted by ions have improved electrical erosion properties.

  5. Treatment of protruding osseo integrated dental implant

    OpenAIRE

    Buddula Aravind; Sheridan Phillip; Balshe Ayman

    2010-01-01

    Titanium dental implants have been used in the treatment of partial or complete edentulism. The height and width of the residual alveolus and surrounding anatomical structures can determine the proper position and path of insertion of dental implants. The following case report describes the treatment of a malpositioned osseo integrated dental implant with an apex perforating the buccal cortex of alveolar bone. A 61-year-old male was referred by his local dentist for the chief complaint of a s...

  6. Antimicrobial technology in orthopedic and spinal implants

    Science.gov (United States)

    Eltorai, Adam EM; Haglin, Jack; Perera, Sudheesha; Brea, Bielinsky A; Ruttiman, Roy; Garcia, Dioscaris R; Born, Christopher T; Daniels, Alan H

    2016-01-01

    Infections can hinder orthopedic implant function and retention. Current implant-based antimicrobial strategies largely utilize coating-based approaches in order to reduce biofilm formation and bacterial adhesion. Several emerging antimicrobial technologies that integrate a multidisciplinary combination of drug delivery systems, material science, immunology, and polymer chemistry are in development and early clinical use. This review outlines orthopedic implant antimicrobial technology, its current applications and supporting evidence, and clinically promising future directions. PMID:27335811

  7. ndophthalmitis Following Glaucoma Drainage Implant Surgery

    OpenAIRE

    Tolga Kocatürk; Erol Erkan; Harun Çakmak

    2014-01-01

    Glaucoma surgery is performed widely in our country and all around the world to lower the intraocular pressure in refractory glaucoma. Glaucoma drainage implant surgery has a special and important place among glaucoma surgeries. Among various complications, endophthalmitis is a rare but the most devastating complication after glaucoma drainage implantation. In this review, the clinical characteristics and treatment options of endophthalmitis after glaucoma drainage implant surgery ar...

  8. ndophthalmitis Following Glaucoma Drainage Implant Surgery

    Directory of Open Access Journals (Sweden)

    Tolga Kocatürk

    2014-03-01

    Full Text Available Glaucoma surgery is performed widely in our country and all around the world to lower the intraocular pressure in refractory glaucoma. Glaucoma drainage implant surgery has a special and important place among glaucoma surgeries. Among various complications, endophthalmitis is a rare but the most devastating complication after glaucoma drainage implantation. In this review, the clinical characteristics and treatment options of endophthalmitis after glaucoma drainage implant surgery are discussed according to recent literature. (Turk J Ophthalmol 2014; 44: 138-43

  9. Immunopathologic effects of silicone breast implants.

    OpenAIRE

    S.S. Teuber; Yoshida, S H; Gershwin, M E

    1995-01-01

    Silicone-gel breast implants have been associated with a myriad of autoimmune and connective tissue disorders by anecdotal reports and small observational series. To date, no prospective epidemiologic studies have been done to substantiate these observations, but an increasing body of literature is being developed and older studies are being recognized that point to immunotoxic or inflammatory effects of these breast implant components. The development of disease due to implants would depend ...

  10. Early History and Challenges of Implantable Electronics

    OpenAIRE

    Ko, Wen H.

    2012-01-01

    Implantable systems for biomedical research and clinical care are now a flourishing field of activities in academia as well as industrial institutions. The broad field includes experimental explorations in electronics, mechanical, chemical, and biological components and systems, and the combination of all these. Today virtually all implants involve both electronic circuits and micro-electro-mechanical-systems (MEMS). This article offers a very brief glance back at the early history of implant...

  11. Extraocular Surgical Approach for Placement of Subretinal Implants in Blind Patients: Lessons from Cochlear-Implants

    OpenAIRE

    Assen Koitschev; Katarina Stingl; Karl Ulrich Bartz-Schmidt; Angelika Braun; Florian Gekeler; Udo Greppmaier; Helmut Sachs; Tobias Peters; Barbara Wilhelm; Eberhart Zrenner; Dorothea Besch

    2015-01-01

    In hereditary retinal diseases photoreceptors progressively degenerate, often causing blindness without therapy being available. Newly developed subretinal implants can substitute functions of photoreceptors. Retina implant extraocular surgical technique relies strongly on cochlear-implant know-how. However, a completely new surgical approach providing safe handling of the photosensor array had to be developed. The Retina Implant Alpha IMS consisting of a subretinal microphotodiode array and ...

  12. Effectiveness of Implant Therapy Analyzed in a Swedish Population: Early and Late Implant Loss

    OpenAIRE

    Derks, J.; Håkansson, J.; Wennström, J.L.; Tomasi, C.; Larsson, M.; Berglundh, T

    2015-01-01

    Treatment outcomes in implant dentistry have been mainly assessed as implant survival rates in small, selected patient groups of specialist or university clinical settings. This study reports on loss of dental implants assessed in a large and randomly selected patient sample. The results were aimed at representing evaluation of effectiveness of implant dentistry. Using the national data register of the Swedish Social Insurance Agency, 4,716 patients were randomly selected. All had been provid...

  13. Injury to the coronary arteries and related structures by implantation of cardiac implantable electronic devices.

    Science.gov (United States)

    Pang, Benjamin J; Barold, S Serge; Mond, Harry G

    2015-04-01

    Damage to the coronary arteries and related structures from pacemaker and implantable cardioverter-defibrillator lead implantation is a rarely reported complication that can lead to myocardial infarction and pericardial tamponade that may occur acutely or even years later. We summarize the reported cases of injury to coronary arteries and related structures and review the causes of troponin elevation in the setting of cardiac implantable electronic device implantation. PMID:25564549

  14. Intra-Articular Knee Contact Force Estimation During Walking Using Force-Reaction Elements and Subject-Specific Joint Model.

    Science.gov (United States)

    Jung, Yihwan; Phan, Cong-Bo; Koo, Seungbum

    2016-02-01

    Joint contact forces measured with instrumented knee implants have not only revealed general patterns of joint loading but also showed individual variations that could be due to differences in anatomy and joint kinematics. Musculoskeletal human models for dynamic simulation have been utilized to understand body kinetics including joint moments, muscle tension, and knee contact forces. The objectives of this study were to develop a knee contact model which can predict knee contact forces using an inverse dynamics-based optimization solver and to investigate the effect of joint constraints on knee contact force prediction. A knee contact model was developed to include 32 reaction force elements on the surface of a tibial insert of a total knee replacement (TKR), which was embedded in a full-body musculoskeletal model. Various external measurements including motion data and external force data during walking trials of a subject with an instrumented knee implant were provided from the Sixth Grand Challenge Competition to Predict in vivo Knee Loads. Knee contact forces in the medial and lateral portions of the instrumented knee implant were also provided for the same walking trials. A knee contact model with a hinge joint and normal alignment could predict knee contact forces with root mean square errors (RMSEs) of 165 N and 288 N for the medial and lateral portions of the knee, respectively, and coefficients of determination (R2) of 0.70 and -0.63. When the degrees-of-freedom (DOF) of the knee and locations of leg markers were adjusted to account for the valgus lower-limb alignment of the subject, RMSE values improved to 144 N and 179 N, and R2 values improved to 0.77 and 0.37, respectively. The proposed knee contact model with subject-specific joint model could predict in vivo knee contact forces with reasonable accuracy. This model may contribute to the development and improvement of knee arthroplasty.

  15. Peri-implantitis: from diagnosis to therapeutics.

    Science.gov (United States)

    Nguyen-Hieu, Tung; Borghetti, Alain; Aboudharam, Gérard

    2012-05-01

    Peri-implantitis is an infection of the tissue around an implant, resulting in the loss of supporting bone. Risk factors for peri-implantitis consist of a history of periodontitis, dental plaque, poor oral hygiene, smoking, alcohol consumption and diabetes. A clinical diagnosis indicates inflammatory signs including bleeding on probing with or without suppuration and a peri-implant pocket depth ≥5 mm. A radiograph shows images of marginal bone loss ≥2 mm. A differential diagnosis of peri-implant mucositis, occlusal overload, retrograde peri-implantitis and inflammatory implant periapical lesions suggests the appropriate treatment in each case. The non-surgical treatment of peri-implantitis, including a mechanical treatment alone or combined with antiseptics or antibiotics can improve clinical parameters in the short term but residual defects may still persist. Surgical treatment such as guided bone regeneration results in a gain of clinical attachment level and bone reconstruction in the long term. The limited effect of laser-assisted therapy needs to be further evaluated. The concept of prevention based on early detection and regular maintenance plays a principal role in reducing the occurrence of peri-implantitis. PMID:22383175

  16. Periodontio-integrated implants: A revolutionary concept

    Directory of Open Access Journals (Sweden)

    Minkle Gulati

    2014-01-01

    Full Text Available Though the fields of regenerative dentistry and tissue engineering have undergone significant advancements, yet its application to the field of implant-dentistry is lacking; in the sense that presently the implants are being placed with the aim of attaining osseointegration without giving consideration to the regeneration of periodontium around the implant. The following article reveals the clinical benefits of such periodontio-integrated implants and reviews the relevant scientific proofs. A comprehensive research to provide scientific evidence supporting the feasibility of periodontio-integrated implants was carried out using various online resources such as PubMed, Wiley-Blackwell, Elsevier etc., to retrieve studies published between 1980 and 2012 using the following key words: "implant," "tissue engineering," "periodontium," "osseo-integration," "osseoperception," "regeneration" (and their synonyms and it was found that in the past three decades, several successful experiments have been conducted to devise "implant supported by the periodontium"that can maintain form, function and potential proprioceptive responses similar to a natural tooth. Based on these staunch evidences, the possibility of the future clinical use of such implant can be strongly stated which would revolutionize the implant dentistry and will be favored by the patients as well. However, further studies are required to validate the same.

  17. Basic concepts and techniques of dental implants.

    Science.gov (United States)

    Tagliareni, Jonathan M; Clarkson, Earl

    2015-04-01

    Dental implants provide completely edentulous and partial edentulous patients the function and esthetics they had with natural dentition. It is critical to understand and apply predictable surgical principles when treatment planning and surgically restoring edentulous spaces with implants. This article defines basic implant concepts that should be meticulously followed for predictable results when treating patients and restoring dental implants. Topics include biological and functional considerations, biomechanical considerations, preoperative assessments, medical history and risk assessments, oral examinations, radiographic examinations, contraindications, and general treatment planning options. PMID:25835792

  18. High energy ion implantation for IC processing

    International Nuclear Information System (INIS)

    In this thesis the results of fundamental research on high energy ion implantation in silicon are presented and discussed. The implantations have been carried out with the 500 kV HVEE ion implantation machine, that was acquired in 1981 by the IC technology and Electronics group at Twente University of Technology. The damage and anneal behaviour of 1 MeV boron implantations to a dose of 1013/cm2 have been investigated as a function of anneal temperature by sheet resistance, Hall and noise measurements. (Auth.)

  19. The case for a generic implant processor.

    Science.gov (United States)

    Strydis, Christos; Gaydadjiev, Georgi N

    2008-01-01

    A more structured and streamlined design of implants is nowadays possible. In this paper we focus on implant processors located in the heart of implantable systems. We present a real and representative biomedical-application scenario where such a new processor can be employed. Based on a suitably selected processor simulator, various operational aspects of the application are being monitored. Findings on performance, cache behavior, branch prediction, power consumption, energy expenditure and instruction mixes are presented and analyzed. The suitability of such an implant processor and directions for future work are given.

  20. US Joint Ventures 2014 revision

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A joint venture is a self-directed partnership of agencies, organizations, corporations, tribes, or individuals that has formally accepted the responsibility of...

  1. Joint Performance and Planning System

    Data.gov (United States)

    US Agency for International Development — A joint State/USAID system hosted by State that integrates resource and performance information at the program level and enables more flexible and frequent entry of...

  2. Campus/Industry Joint Ventures.

    Science.gov (United States)

    McDonald, Eugene J.

    1985-01-01

    Opportunities for joint economic ventures of colleges and industry are discussed, and a variety of ventures undertaken by Duke University are outlined, including a health club, hotel, and office building. Tax and financing considerations are noted. (MSE)

  3. Joint audits - benefit or burden?

    DEFF Research Database (Denmark)

    Holm, Claus; Thinggaard, Frank

    In this paper we examine whether there are perceived and observed benefits or burdens from using two audit firms instead of one. In 2005 the mandatory joint audit requirement was abolished in Denmark. This provides a unique setting for studying the consequences and implications of going from...... a joint audit regime to a single auditor/voluntary joint audit regime. The dataset used in this paper has been collected for the full population of non-financial Danish companies listed on the Copenhagen Stock Exchange (CSE) in the years 2004 and 2005. We find that a majority of firms perceive joint...... driving-force behind this seems to be initial price cuts due to competition. However, the results indicate that efficiency gains may also be part of the explanation. We do not find either a general or marginal Big Four effect in the Danish audit market....

  4. Torsion testing of bed joints

    DEFF Research Database (Denmark)

    Hansen, Klavs Feilberg; Pedersen, Carsten Mørk

    2008-01-01

    This paper describes a simple test method for determining the torsion strength of a single bed joint between two bricks and presents results from testing using this test method. The setup for the torsion test is well defined, require minimal preparation of the test specimen and the test can...... be carried out directly in a normal testing machine. The torsion strength is believed to be the most important parameter in out-of-plane resistance of masonry walls subjected to bending about an axis perpendicular to the bed joints. The paper also contains a few test results from bending of small walls about...... an axis perpendicular to the bed joints, which indicate the close connection between these results and results from torsion tests. These characteristics make the torsion strength well suited to act as substitute parameter for the bending strength of masonry about an axis perpendicular to the bed joints....

  5. Finishing touch to joint venture

    CERN Multimedia

    2003-01-01

    "A new process for polishing titanium and its alloys has been announced following an agreement between Bripol (an Anopol/Delmet joint venture) of Birmingham and the European Organisation for Nuclear Reseach (CERN) in Geneva" (1 paragraph).

  6. The implant surface characteristics and peri-implantitis. An evidence-based update.

    Science.gov (United States)

    Peixoto, C Davila; Almas, K

    2016-03-01

    Peri-implantitis is an inflammatory disease of the peri-implant mucosa with the loss of supporting bone. Because of the absence of an un-inflamed connective tissue zone between the healthy and diseased sites, peri-implant lesions are thought to progress more rapidly than periodontal lesions, suggesting the importance of early diagnosis and intervention if possible. A number of risk factors have been identified that may lead to the initiation and progression of peri-implant mucositis and peri-implantitis, eg., previous periodontal disease, poor plaque control, inability to clean, residual cement, smoking, genetic factors, diabetes, occlusal overload, rheumatoid arthritis, increased time of loading and alcohol consumption. At present there is not much literature available, highlighting the relationship between implant surface characteristics and peri-implant diseases. Implant surface characteristics vary with respect to topography, roughness and clinical composition, including turned, blasted, acid etched, porous sintered, oxidized, plasma sprayed and hydroxyapatite coated surfaces and their combinations. So the aim of this review is to explore the relationship between the characteristics of implant surface, the prevalence and incidence of peri-implantitis. This would help to identify plausible influence of surface characteristics, oral hygiene instructions and maintenance of implants for the long-term uneventful success of implant therapy. PMID:27434917

  7. Investigation of the Effects of Abutment and Implant Length on Stability of Short Dental Implants

    Directory of Open Access Journals (Sweden)

    Eda OZYILMAZ

    2015-01-01

    Full Text Available The use of dental implants to solve different problems in dentistry has been growing rapidly. The success rates of dental implants are also very important for patients. Depending on the bone level of patients, short dental implants are very popular and widely used by many dentists. Although many dentists are using short dental implants frequently, It can be guessed that there can be stability problems because of crown to implant ratios. In this study, it is aimed to find out the effects of dental implant and abutment lengths on stability of short dental implants. 3 different short dental implant design made with the use of Solidworks 2013. Abutment lengths were 3,5 mm, 4 mm, 4,5 mm, 5 mm and implant lengths were 5 mm, 6 mm, 7 mm for each model. Human mandible model is transferred from Computed Tomography. Then, each implant model is mounted to modeled mandible and Finite Element Analysis is performed for each model. In order to see the effects of implant number on stability, we performed same analysis by placing 4 implants to the mandible

  8. Influence of shoes and heel strike on the loading of the hip joint.

    Science.gov (United States)

    Bergmann, G; Kniggendorf, H; Graichen, F; Rohlmann, A

    1995-07-01

    The forces and moments acting at the hip joint influence the long-term stability of the fixation of endoprostheses and the course of coxarthrosis. These loads may depend on the kind of footwear and the walking or running style. These factors were investigated in a patient with instrumented hip implants. He wore different sports shoes, normal leather shoes, hiking boots and clogs and walked barefoot with soft, normal and hard heel strikes. The loads were lowest while walking and jogging without shoes. All shoes increased the joint force and the bending moment at the implant slightly but the torsional moment rose by up to 50%. No relation was found between the different type of shoes and the load increase, only shoes with very hard soles were clearly disadvantageous. Soft heels, soles or insoles did not offer advantages. Gait stability seems to play the most important role in increasing the joint loading and should be the criterion for the choice of footwear. Smooth gait patterns with soft heel strikes are the only means to reduce joint loading during slow jogging. PMID:7657680

  9. IRS memorandum limits joint ventures.

    Science.gov (United States)

    Herman, A W

    1992-08-01

    Based on a new memorandum, the Internal Revenue Service (IRS) will be looking at joint hospital/physician activities with greater attention to the nuances of public versus private benefit. As a result, hospitals face greater risk of losing their tax-exempt status in the maze of joint ventures, physician recruitment, and practice acquisition. To be successful, ventures will have to be backed by sound reasoning and thorough documentation.

  10. "Fraud alert": joint venture arrangements.

    Science.gov (United States)

    Vipperman, R M

    1989-01-01

    The Office of Inspector General of the Department of Health and Human Services recently issued a special "Fraud Alert" identifying those characteristics of joint venture arrangements that it views as indicators of potentially unlawful activity. As discussed in this article, participants in joint ventures should examine their arrangements to see if one or more of the questionable features are present, and, if so, should take steps to eliminate them, to the extent possible.

  11. Joint probabilities and quantum cognition

    CERN Document Server

    de Barros, J Acacio

    2012-01-01

    In this paper we discuss the existence of joint probability distributions for quantum-like response computations in the brain. We do so by focusing on a contextual neural-oscillator model shown to reproduce the main features of behavioral stimulus-response theory. We then exhibit a simple example of contextual random variables not having a joint probability distribution, and describe how such variables can be obtained from neural oscillators, but not from a quantum observable algebra.

  12. Fracture dynamics in implanted silicon

    Science.gov (United States)

    Massy, D.; Mazen, F.; Tardif, S.; Penot, J. D.; Ragani, J.; Madeira, F.; Landru, D.; Kononchuk, O.; Rieutord, F.

    2015-08-01

    Crack propagation in implanted silicon for thin layer transfer is experimentally studied. The crack propagation velocity as a function of split temperature is measured using a designed optical setup. Interferometric measurement of the gap opening is performed dynamically and shows an oscillatory crack "wake" with a typical wavelength in the centimetre range. The dynamics of this motion is modelled using beam elasticity and thermodynamics. The modelling demonstrates the key role of external atmospheric pressure during crack propagation. A quantification of the amount of gas trapped inside pre-existing microcracks and released during the fracture is made possible, with results consistent with previous studies.

  13. Implantation und Komplikation der Vagusnervstimulation

    Directory of Open Access Journals (Sweden)

    Spuck S

    2007-01-01

    Full Text Available Weltweit wurden bis zum Beginn des Jahres 2007 45.000 Vagusnervstimulatoren (VNS implantiert. Trotz der häufigen Operationen sind nur wenige Berichte über Komplikationen veröffentlicht. Die primäre operative Implantation ist ein sicheres Verfahren. Komplikationen und Nebenwirkungen können nach operations-, material- und stimulationsassoziiertem Ursprung unterteilt werden. Erforderliche Revisionseingriffe sind insbesondere bei Kindern anspruchsvoll. Im folgenden Artikel werden mögliche Probleme der VNS-Therapie und deren Behandlung dargestellt.

  14. Towards Long-Life Replacement Joint Prostheses - A Surface Engineering Approach

    Institute of Scientific and Technical Information of China (English)

    Hanshan Dong

    2004-01-01

    How to improve the wear resistance of bearing surfaces, hereby achieving long life of orthopaedic joint prostheses has long been a technical challenge with much fundamental interest and social and economic impacts. Surface engineering has been emerging as one of the most promising technologies to improve the tribological properties of biomedical materials.A current area of research within the Birmingham Surface Engineering Group has been directed at developing novel surface engineering technologies for biomedical materials towards long-life joint prostheses. Following a brief introduction, the author reports their recent progress in the surface engineering of biomedical materials particular for joint prosthesis. The potential of these innovative surface engineering technologies in enhancing the performance of oral and maxillofacial implants and surgical devices is also discussed.

  15. Towards Long-Life Replacement Joint Prostheses-A Surface Engineering Approach

    Institute of Scientific and Technical Information of China (English)

    HanshanDong

    2004-01-01

    How to improve the wear resistance of bearing surfaces, hereby achieving long life of orthopaedic joint prostheses has long been a technical challenge with much fundamental interest and social and economic impacts. Surface engineering has been emerging as one of the most promising technologies to improve the tribological properties of biomedical materials. A current area of research within the Birmingham Surface Engineering Group has been directed at developing novel surface engineering technologies for biomedical materials towards long-life joint prostheses. Following a brief introduction, the author reports their recent progress in the surface engineering of biomedical materials particular for joint prosthesis. The potential of these innovative surface engineering technologies in enhancing the performance of oral and maxillofacial implants and surgical devices is also discussed.

  16. A Review of Dental Implant Treatment Planning and Implant Design Based on Bone Density

    Directory of Open Access Journals (Sweden)

    Torkzaban

    2013-06-01

    Full Text Available Context A key determinant for clinical success is the diagnosis of the bone density in a potential implant site. The percentage of bone-implant contact is related to bone density, and the axial stress contours around an implant are affected by the density of bone. Evidence Acquisition A number of reports have emphasized the importance of the quality of bone on the survival of dental implants. The volume and density of the recipient bone have also been shown to be determining criteria to establish proper treatment plans with adequate number of implants and sufficient surface area. Previous clinical reports that did not alter the protocol of treatment related to bone density had variable survival rates. To the contrary, altering the treatment plan to compensate for soft bone types has provided similar survival rates in all bone densities. Results When bone density decreases and bone become softer, the implant surface in contact with the bone decreases, therefore treatment plan should be modified by changing the drilling protocol, using gradual loading and reducing the force on the prosthesis or increasing the loading area with increasing implant number, implant position, implant size, implant design (deeper and more threads with more pitch, squared shape and implant body surface condition. Conclusions Once the prosthetic option, key implant position, and patient force factors have been determined, the bone density in the implant sites should be evaluated to modify the treatment plan. Inappropriate implant number or design in poor quality bone results in higher failure rates. Changing the treatment plan and implant design is suggested, based on bone density to achieve higher survival rates.

  17. Long-Term Symptoms Onset and Heterotopic Bone Formation around a Total Temporomandibular Joint Prosthesis: a Case Report

    Directory of Open Access Journals (Sweden)

    Luca Guarda-Nardini

    2014-04-01

    Full Text Available Background: The literature on total alloplastic temporomandibular joint (TMJ reconstructions is encouraging, and studies on total alloplastic TMJ replacements outcomes showed acceptable improvements in terms of both pain levels and jaw function. Nevertheless, some adverse events, such as heterotopic bone formation around the implanted prosthesis, may occur. In consideration of that, the present manuscript describes a case of heterotopic bone formation around a total temporomandibular joint prosthesis, which occurred several years after the implant. Methods: The present manuscript describes a case of heterotopic bone formation around a total TMJ prosthesis, which occurred several years after the implant in patients, who previously underwent multiple failed TMJ surgeries. Results: Ten years after the surgical TMJ replacement to solve an ankylotic bone block, the patient came to our attention again referring a progressive limitation in mouth opening. A computerized tomography showed evidence of marked heterotopic bone formation in the medial aspects of the joint, where a new-born ankylotic block occupied most part of the gap created by resecting the coronoid process at the time of the TMJ prosthesis insertion. Conclusions: Despite this adverse event has been sometimes described in the literature, this is the first case in which its occurrence happened several years after the temporomandibular joint replacement. It can be suggested that an accurate assessment of pre-operative risk factors for re-ankylosis (e.g., patients with multiple failed temporomandibular joint surgeries and within-intervention prevention (e.g., strategies to keep the bone interfaces around the implant separated should be better standardized and define in future studies.

  18. Implantation of scaffold-free engineered cartilage constructs in a rabbit model for chondral resurfacing.

    Science.gov (United States)

    Brenner, Jillian M; Ventura, Nicole M; Tse, M Yat; Winterborn, Andrew; Bardana, Davide D; Pang, Stephen C; Hurtig, Mark B; Waldman, Stephen D

    2014-02-01

    Joint resurfacing techniques offer an attractive treatment for damaged or diseased cartilage, as this tissue characteristically displays a limited capacity for self-repair. While tissue-engineered cartilage constructs have shown efficacy in repairing focal cartilage defects in animal models, a substantial number of cells are required to generate sufficient quantities of tissue for the repair of larger defects. In a previous study, we developed a novel approach to generate large, scaffold-free cartilaginous constructs from a small number of donor cells (20 000 cells to generate a 3-cm(2) tissue construct). As comparable thicknesses to native cartilage could be achieved, the purpose of the present study was to assess the ability of these constructs to survive implantation as well as their potential for the repair of critical-sized chondral defects in a rabbit model. Evaluated up to 6 months post-implantation, allogenic constructs survived weight bearing without a loss of implant fixation. Implanted constructs appeared to integrate near-seamlessly with the surrounding native cartilage and also to extensively remodel with increasing time in vivo. By 6 months post-implantation, constructs appeared to adopt both a stratified (zonal) appearance and a biochemical composition similar to native articular cartilage. In addition, constructs that expressed superficial zone markers displayed higher histological scores, suggesting that transcriptional prescreening of constructs prior to implantation may serve as an approach to achieve superior and/or more consistent reparative outcomes. As the results of this initial animal study were encouraging, future studies will be directed toward the repair of chondral defects in more mechanically demanding anatomical locations. PMID:24571514

  19. 12 CFR 347.107 - Joint ventures.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 4 2010-01-01 2010-01-01 false Joint ventures. 347.107 Section 347.107 Banks... INTERNATIONAL BANKING § 347.107 Joint ventures. (a) Joint ventures. If a bank, directly or indirectly, acquires or holds an equity interest in a foreign organization that is a joint venture, and the bank or...

  20. Condylar hyperplasia following unilateral temporomandibular joint replacement.

    Science.gov (United States)

    Machon, V; Levorova, J; Hirjak, D; Foltan, R

    2015-06-01

    Total joint replacement of the temporomandibular joint (TJR) can be associated with intraoperative and postoperative complications. We report herein the occurrence of a postoperative open bite malocclusion, the result of condylar hyperplasia affecting the non-operated joint at 1 year after unilateral total joint replacement. PMID:25662429