Showing papers on "Prosthesis published in 2007"

Sonication of Removed Hip and Knee Prostheses for Diagnosis of Infection

Abstract: Background Culturing of samples of periprosthetic tissue is the standard method used for the microbiologic diagnosis of prosthetic-joint infection, but this method is neither sensitive nor specific. In prosthetic-joint infection, microorganisms are typically present in a biofilm on the surface of the prosthesis. We hypothesized that culturing of samples obtained from the prosthesis would improve the microbiologic diagnosis of prosthetic-joint infection. Methods We performed a prospective trial comparing culture of samples obtained by sonication of explanted hip and knee prostheses to dislodge adherent bacteria from the prosthesis with conventional culture of periprosthetic tissue for the microbiologic diagnosis of prosthetic-joint infection among patients undergoing hip or knee revision or resection arthroplasty. Results We studied 331 patients with total knee prostheses (207 patients) or hip prostheses (124 patients); 252 patients had aseptic failure, and 79 had prosthetic-joint infection. With the use o...

The Use of the Reverse Shoulder Prosthesis for the Treatment of Failed Hemiarthroplasty for Proximal Humeral Fracture

Abstract: Background: Humeral hemiarthroplasty is an established treatment for patients with selected fractures of the proximal part of the humerus. However, a subset of patients have development of glenoid arthritis and rotator cuff deficiency due to tuberosity failure. To date, there has been no reliable salvage procedure for this problem. Methods: Over a period of five years, twenty-nine patients (twenty-five women and four men) with a mean age of sixty-nine years (range, forty-two to eighty years) were managed with removal of a hemiarthroplasty prosthesis and revision with a Reverse Shoulder Prosthesis alone or in combination with a proximal humeral allograft. Patients were followed clinically and radiographically for an average of thirty-five months. All patients were evaluated with use of the American Shoulder and Elbow Surgeons score; the Simple Shoulder Test; range-of-motion measurements, including abduction, forward flexion, and external rotation; and a rating scale for overall satisfaction with the outcome of the surgery. Patients were assessed preoperatively and at all follow-up points beginning at three months postoperatively. Results: The average total American Shoulder and Elbow Surgeons score improved from 22.3 preoperatively to 52.1 at the time of the last follow-up (p < 0.001). The average American Shoulder and Elbow Surgeons pain score improved from 12.2 to 34.4 (p < 0.001), and the average American Shoulder and Elbow Surgeons function score improved from 10.1 to 17.7 (p = 0.058). The average Simple Shoulder Test score improved from 0.9 to 2.6 (p = 0.004). Forward flexion improved from 38.1° to 72.7° (p < 0.001), and abduction improved from 34.1° to 70.4° (p < 0.001). The overall complication rate was 28% (eight of twenty-nine). At the time of the latest follow-up, sixteen patients rated the outcome as good or excellent, seven rated it as satisfactory, and six were dissatisfied. Four of the six patients who were dissatisfied had been managed with a Reverse Shoulder Prosthesis alone. Conclusions: The Reverse Shoulder Prosthesis offers a salvage-type solution to the problem of failed hemiarthroplasty due to glenoid arthritis and rotator cuff deficiency following tuberosity failure. The early results reported here are promising. In cases of severe proximal humeral bone deficiency, augmentation of the Reverse Shoulder Prosthesis with a proximal humeral allograft may improve patient satisfaction. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Immediate rehabilitation of the completely edentulous jaw with fixed prostheses supported by either upright or tilted implants: a multicenter clinical study

Abstract: Purpose: The aims of this study were to assess the treatment outcome of immediately loaded full-arch screw-retained prostheses with distal extensions supported by both upright and tilted implants for the rehabilitation of edentulous jaws and to compare the outcomes of upright versus tilted implants. Materials and Methods: At 4 study centers, 342 Osseotite NT implants were consecutively placed in 65 patients (96 implants were placed in 24 mandibles and 246 implants in 41 maxillae). The 2 distal implants were tilted by 25 to 35 degrees. Provisional full-arch restorations made of a titanium framework and acrylic resin teeth were delivered within 48 hours of surgery and immediately loaded. The final prosthesis was delivered after 3 months of healing. Results: Three implants failed during the first year and another 2 within 18 months of loading in the maxilla. The cumulative implant survival rate for the maxilla was 97.59% for up to 40 months of follow-up. No implant failure was recorded for the mandible. The prosthetic success rate was 100%. Marginal bone loss around upright and tilted implants was similar. Patients were satisfied of their esthetics, phonetics, and function. Conclusion: The preliminary results of this study suggest that immediate rehabilitation of the edentulous maxilla and mandible by a hybrid prosthesis supported by 6 or 4 implants, respectively, may represent a viable treatment alternative with respect to more demanding surgical procedures. The clinical results indicate that immediately loaded tilted implants may achieve the same outcome as upright implants in both jaws. (Clinical Trial) INT J ORAL MAXILLOFAC IMPLANTS 2007;22:639–644

Radial Head Arthroplasty with a Modular Metal Spacer to Treat Acute Traumatic Elbow Instability

Abstract: BACKGROUND: The use of a metal radial head prosthesis to help stabilize an elbow with traumatic instability is appealing because internal fixation of multifragment, displaced fractures of the radial head is susceptible to either early or late failure. The newer modular prostheses are easier to size and implant, but their effectiveness has not been investigated, to our knowledge. METHODS: Twenty-seven patients in whom a radial head replacement with a modular metal spacer prosthesis had been performed to treat traumatic elbow instability were evaluated with use of the Mayo Elbow Performance Index (MEPI), the American Shoulder and Elbow Surgeons Elbow Evaluation Instrument (ASES), and the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH). Radiographs were evaluated for arthrosis, periprosthetic radiolucency, and heterotopic ossification. RESULTS: Seven patients underwent one or more subsequent operations to treat residual instability, heterotopic ossification and elbow contracture, ulnar neuropathy, or a misplaced screw. In two of these patients, the prosthesis was removed as part of an elbow contracture release or to treat infection. At an average of forty months postoperatively, elbow motion in the entire group of twenty-seven patients averaged 131° of flexion with a 20° flexion contracture, 73° of pronation, and 57° of supination. Stability was restored to all twenty-seven elbows, and twenty-two patients had a good or excellent result according to the MEPI. Seventeen patients had radiographic evidence of lucency around the neck of the prosthesis that was not associated with increased pain, thirteen patients had clinically inconsequential heterotopic ossification anterior to the radial neck, and nine patients had radiographic changes in the capitellum. CONCLUSIONS: An intentionally loosely placed modular metal radial head prosthesis can help to restore stability in conjunction with repair of other fractures and reattachment of the lateral collateral ligament to the epicondyle in the setting of traumatic elbow instability with a comminuted fracture of the radial head. While a prosthesis that is too large can cause problems, lucencies around the stem of the intentionally loose prosthesis and most changes in the capitellum do not appear to cause problems, at least in the short term. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence. ORIGINAL ABSTRACT CITATION: “Radial Head Arthroplasty with a Modular Metal Spacer to Treat Acute Traumatic Elbow Instability” (2007;89:1075-80).

Midterm results with a bipolar radial head prosthesis: radiographic evidence of loosening at the bone-cement interface.

Abstract: Background: Metal prostheses are useful for restoring elbow and forearm stability when the radial head cannot be fixed after a fracture. Because the anatomy of the radial head is difficult to reproduce with a prosthesis, two different options have been proposed: a bipolar prosthesis with a fixed stem and a mobile head, and a monoblock prosthesis with a smooth stem that is intentionally fixed loosely in the neck of the radius. One concern with a fixed-stem implant with a mobile head has been the risk of osteolysis. The purpose of this study was to evaluate radiographic changes reflecting or suggesting progressive osteolysis in patients with a bipolar radial head prosthesis. Methods: The functional and radiographic outcomes following treatment of fifty-one comminuted fractures of the radial head with a bipolar radial head prosthesis in fifty-one consecutive patients were evaluated at a mean of 8.4 years postoperatively. There were eleven isolated comminuted fractures involving the entire radial head. Thirty-four fractures were associated with a posterior elbow dislocation, and six patients had a posterior Monteggia lesion. Results: According to the Mayo Elbow Performance Index, fourteen elbows were graded as excellent; twenty-five, as good; nine, as fair; and three, as poor. Radiographic changes reflecting or suggesting progressive osteolysis were present in thirty-seven patients. Complications occurred in ten patients, but only one underwent surgical treatment, for an ulnar neuropathy. Conclusions: Although satisfactory midterm functional results were achieved in thirty-nine of the fifty-one patients, the high prevalence of adverse radiographic changes suggesting periprosthetic osteolysis should alert clinicians to this possible drawback of the use of bipolar radial head prostheses, especially in young and/or active patients. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Which mechanical and physical testing methods are relevant for predicting the clinical performance of ceramic-based dental prostheses?

Abstract: Purpose: The survival and performance of clinical prostheses with a ceramic component are probabilistic in nature. Only under very rare circumstances will all of the prostheses in a group exhibit either 100% successes or 100% failures over a period of 5 years or more. Prosthesis failure may be defined as any condition that leads to replacement. These conditions include secondary caries, irreversible pulpitis, excessive wear of opposing tooth surfaces, excessive erosion and roughening of the ceramic surface, ditching of the cement margin, unacceptable esthetics, cracking, chipping and fracture. A systematic review of the dental literature was performed to determine the extent to which the mechanical and physical properties of dental alloys and ceramics can predict the 5-year clinical performance of metal-ceramic and all-ceramic fixed dental prostheses (FDP) and to determine the associated quality of reported outcomes associated with these clinical studies. Materials and methods: The review was based on clinical research studies of 5 years or greater duration that were published in English dental journals between 1980 and 2006 using the following key words and MeSH terms. Our search strategy was as follows: Search 1: Partial fixed denture OR denture, partial, fixed OR denture, partial fixed OR dental porcelain OR metal ceramic alloys OR dental ceramic Search 2: Prosthesis failure OR dental restoration failure OR time factors OR survival analysis Search 3: Meta-analysis OR evaluation studies OR review OR clinical trial OR comparative study OR follow-up studies OR prospective studies OR clinical follow-up study OR clinical trial OR longitudinal studies Inclusion of searches 1, 2 and 3 and limits placed on the publication date starting on January 1, 1980, English language, and clinical studies involving humans resulted in a total of 684 articles. By restricting the clinical studies to 5 years or more in duration, the number was reduced to 193. By eliminating resin-bonded FDPs, cantilever designs, implant-supported prostheses, crowns, inlay- or onlay-supported prostheses, a total of 37 articles remained for detailed review. After excluding review articles and articles involving resin-bonded bridges, single-author clinical research articles, cantilever designs and implant-supported FDPs, 11 clinical research articles remained. For these articles, it was not possible to determine conclusively the probability of failure for three-unit FDPs compared with four-unit and larger prostheses or the location of the crowns and pontics. Results: This systematic review of studies on ceramic-based FDPs confirms the results of previous studies that, in most cases, <15% of these prostheses were removed or were in need of replacement at 10 years. However, there was considerable variability in the number of parameters that were reported as well as the range of details on failures that occurred. In some studies, a standardized evaluation system was used in which USPHS or Ryge criteria were applied. However, there was also great uncertainty in the definition of failure with respect to repairable fractures and whether the identified causative factors were directly or indirectly associated with the replacement of the prostheses. Conclusions: This review indicates that there is no single in vitro test variable that can predict clinical performance in these prostheses. Based on these reviews, there is an urgent need to develop a comprehensive classification system for identifying clinical prosthesis failures, technical complications and biologic complications. Guidelines on the retrieval of fractured prostheses and/or impressions that capture the fracture surface details should also be developed. The predictive power of in vitro data can be increased by finite element stress analysis and computer programs such as the CARES/Life software (NASA Lewis Research Center, Cleveland, OH) that estimates the time-dependent nature of ceramic structure survival.

Rotating hinged total knee replacement : Use with caution

Abstract: Background: A rotating hinged total knee prosthesis may be utilized for the treatment of global instability or severe bone loss around the knee. Older generations of rotating hinged designs were associated with suboptimal outcomes. We evaluated the outcome of salvage knee reconstructions that had been performed with use of modern-generation modular segmental kinematic rotating hinged total knee prostheses. Methods: The cohort included forty-three patients (twenty-nine women and fourteen men) who underwent forty-four knee arthroplasties for the treatment of a non-neoplastic condition with use of a modern-generation kinematic rotating hinged prosthesis. Revision of a previous total knee arthroplasty in the presence of massive bone loss was the most common indication for surgery. Complete clinical and radiographic data were collected for all patients after a mean duration of follow-up of 4.2 years. Results: Reconstruction with a rotating hinged total knee prosthesis provided substantial improvement in function and reduction in pain. However, a relatively large number of complications and failures (including revision because of periprosthetic infection [three knees], aseptic loosening [four], and periprosthetic fracture [one]) were encountered, with a mean time to failure of 1.7 years. The rate of prosthetic survival was 79.6% at one year and 68.2% at five years with revision or reoperation as the end point. Conclusions: The present study highlights the commonly held opinion that a modular kinematic rotating hinged total knee prosthesis has a role for salvage reconstruction of the knee. In light of the relatively high rate of complications, we believe that this salvage procedure should be reserved primarily for elderly and sedentary patients. Level of Evidence: Therapeutic Level IV. See Instructions to Authors for a complete description of levels of evidence.

Factors affecting late implant bone loss: a retrospective analysis.

Abstract: PURPOSE Prevention of late implant bone loss is a critical component in long-term success of implants. The aim of the present study was to evaluate factors affecting late implant bone loss. MATERIALS AND METHODS Three hundred thirty-nine endosseous root-form dental implants placed between April 1981 and April 2002 in 69 patients were analyzed. The implants were categorized based on the following factors: (1) surface characteristics (smooth versus rough), (2) length (short [ or = 10 mm]), width (narrow [ 4.0 mm]), (3) the amount of keratinized mucosa ( or = 2 mm), (4) location (anterior versus posterior; maxilla versus mandible), (5) type of prosthesis (fixed versus removable), and (6) type of opposing dentition. The effects of these factors on clinical parameters, especially average annual bone loss (ABL), were evaluated clinically and radiographically by a blinded examiner. The parameters evaluated were modified Plaque Index, Gingival Index, modified Bleeding Index, probing depth, and ABL. RESULTS Shorter implants, wider implants, implants supporting fixed prostheses, and implants in smokers were found to be associated with greater ABL (P < .05). The random intercept mixed effects model showed that implant length was the most critical factor for maintenance of ABL. CONCLUSIONS Shorter implants, wider implants, implants supporting fixed prostheses, and implants in smokers were associated with greater ABL. Implant length was the most significant factor in the maintenance of dental implants. Randomized controlled clinical trials are needed to confirm the results obtained from this retrospective clinical study.

Computer-aided custom-made hemipelvic prosthesis used in extensive pelvic lesions.

Abstract: We review here our experience in the computer-aided design and manufacture and implantation of custom-made hemipelvic prostheses in 10 patients who underwent internal hemipelvectomy for extensive pelvic lesions. Computed tomography data and the rapid prototyping technique were used to make a precise model of each patient's pelvis for the simulated hemipelvectomy; the model was used to design and manufacture prostheses that were easy to implant because the location and orientation of the acetabulum was readily adjustable. Four patients died 6 to 10 months after surgery; the remaining 6 patients, monitored for 21 to 48 months, all had good hip function. There were early hip dislocations in 2 patients and wound-healing problems in 3, but all were treated successfully.

Excentered scapulohumeral osteoarthritis

Abstract: Cuff tear arthropathy is defined as the combination of a gleno-humeral arthritis and a massive rotators cuff tear. It is generally admitted that the cuff tear, or its deficiency jeopardises the results of anatomic prosthesis. Grammont imagined and grew the concept of the reverse prosthesis whose aim was to remedy the insufficiency of the rotator cuff and whose use has dramatically modified the therapeutic approach in these complicated situations. The aim of this symposium is to analyse the results of shoulder arthroplasty (anatomic prosthesis, bipolar or reverse) in cuff tear arthropathy, in massive and isolated cuff tears which justify the use of prosthetic surgery, and in centered osteoarthritis with deficient cuff also justifying this use. Massive cuff tears and cuff tear arthropathy have been considered as the stages of a same pathology by Hamada whose classification has been used for the purposes of this study. Out of the 738 initial prosthesis, 111 have been eliminated because of death, incomplete files or lost of sight, without any known complication. Out of the remaining 627 who were used as a basis for this symposium (representing 85% of initial cases), 570 who still had their prosthesis were reviewed and their functional results analysed after 2 years or more. The population was mainly female (72%) who were injured on the dominant side (75%) with a mean age of 72 years. The preoperative Constant score was in average 24 and 24% of the patients had already been operated on their shoulder. For those who had an acetabulization of the acromion, the strength in external rotation was significantly less satisfying and the lesion of the infraspinatus and the teres minor were more frequent. 48 hemiarthroplasties, 52 bipolar and 527 reverse prosthesis were studied. At revision, with an average follow up of 52 months, the revision rate was 23% for hemiarthroplasties, 14% for reversed prosthesis and only 8% for bipolar prosthesis. The prosthesis was removed in 21% of hemiarthroplasties, 5% of reverse and 2% of bipolar. No infection to report in the hemi group or the bipolar group, whereas there was an infection rate of 5% in the reverse group. Nevertheless, the Constant score was significantly better with reverse (62) than with bipolar (45) or hemi (44). The active elevation was also better with the reverse whereas the external rotation was not as good as with anatomic prosthesis. The analytic study of the results of the reverse prosthesis shows a negative influence of the lesion of the sub-scapularis and the teres minor. The results are disappointing with young patients and those who had surgical precedents. On X-ray, we can notice 0.5% of humeral loosening withouth any correlation to the fact that the implant is cemented or not, 3.6% of glenoid loosening and 68% of scapular notches without any significant change on the Constant score. Their occurrence is correlated to a preoperative rising of the humeral head and a superior glenoid lesion. It is observed more frequently with the supero-lateral approach compared to the delto-pectoral one. The frequency of these notches grows with the follow up and their occurrence is often associated to humeral radiolucent lines. On the long term, the survival rate of these prosthesis is 89% at 10 years. The Constant score deteriorates gradually after 7 years; this seems to be linked to the occurrence of x-ray modifications in the years that followed. The main complications observed with reverse prosthesis were the infections (5.1%), the glenoid problems (5.1%), the instabilities (3.6%), the acromion fractures (3.0%). Infections can be treated by a wash out and antibiotics in the first 3 months, then the removal of the prosthesis becomes necessary. The instabilities occur more often for males, with delto-pectoral approach and with 36mm diameter glenoids. The glenoid problems are frequent in the first years and often due to technical errors or material defects (unscrewing of the glenosphere). Acromion fractures have an important clinical impact when they concern the spine and there healing is difficult to obtain, whichever method is used. In conclusion, the use of a prosthesis for cuff tear arthropathies must be thought about, especially in massive cuff tear without osteoarthritis, in patients with previous surgery, and in patients younger than 70. If the active elevation is conserved and the patient is young, the use of an hemi or a bipolar prosthesis can be debated. In other cases, the indication of a reverse prosthesis is preferable given that the clinical results are better. In these cases, the surgical technique must be accurate, bearing in mind the advantages and disadvantages of the two possible approaches, the type of implant (36 vs 42), the position and orientation of the glenoid baseplate according to the pre-operative bone wear, the orientation of the humeral implant, the need for reinsertion of the subscapularis and, maybe, the possibility of an associated transfer of the latissimus dorsi.

Custom made cranioplasty prostheses in porous hydroxy-apatite using 3D design techniques: 7 years experience in 25 patients.

Abstract: Background. None of the materials currently used to reconstruct skull defects is fully satisfactory. Their biological and physical properties are very different to those of natural bone. Solid state, high porosity hydroxy-apatite (HA) seems to be a good support for bone regeneration within the prostheses, enabling integration of the heterologous material with low post-implant infective risk. Materials and methods. A model of the cranium of each patient was made in epoxy resin by stereolithography. The prosthesis was built on this model using a ceramic sintering process. In each case, an exact copy of the missing bone flap was obtained (curvature, dimensions, margins, irregularities and thickness). The porosity obtained is the same as that of the spongy bone of the skull with interconnected macropores (>150 µm) to promote osteoblast migration into the prosthetic core. In The Neurosurgery Division of Cesena, 26 cranioplasty prostheses have been implanted with this technique in 7 years (from 1998 to 2004). No particular criteria were pre-established, but the main indications for use of ceramic prostheses were complex and/or extended (surface >25 cm2) post-surgery craniolacuna and/or previous unsuccessful procedures due to rejection, infection or bone flap reabsorption. Results. Twenty-five patients were included in this study. A clinical check-up and 3D CT (mean follow-up 30 months, range 12–79) always showed an excellent aesthetic result. No cases of infection, rejection or spontaneous prosthesis fragmentation were found. The surgical procedure was simpler and shorter than for other described procedures. Conclusions. Bioceramic porous hydroxy-apatite prosthesis have been demonstrated as a valid alternative to traditional cranioplasty techniques both aesthetically and in terms of absence of infections/rejections. Principal limitations for the use of HA prostheses are the need for stereolithography process, the poor malleability of the material and the high cost.

Management of Periprosthetic Femur Fractures With a First Generation Locking Plate

Abstract: Summary Periprosthetic femoral fractures associated with well-fixed total hip or total knee prostheses present a challenging management problem as these injuries typically occur in osteoporotic bone. Conventional management entails extensive periosteal stripping to allow for plate fixation. We reviewed a consecutive series of patients who sustained fractures associated with a well fixed total knee prosthesis, a total hip prosthesis, or both. Twenty four patients with a mean age of 69.4 years were included. All patients underwent fixation via percutaneous insertion techniques with a first generation locking plate and screws (LISS—Less Invasive Skeletal Stabilization, Synthes, Paoli, PA). Three patients sustained fractures distal to a well-fixed total hip prosthesis, eighteen fractures occurred above a well-fixed total knee femoral component, and three were interprosthetic. The mean length of time from the index procedure to fracture was 76 months, range (2–172 months). Blood loss was minimal in each case, with a mean operative time of 90 min (range 60–120 min). Twenty one of twenty four went on to unite at a mean 6.2 months (range 3–19 months). Three patients underwent further surgery. One failure of fixation was encountered. Percutaneous fixation is technically demanding as it requires stable fixation without direct visualisation of the fracture site or the entire fixation device. Our results suggest percutaneous fixation with the LISS plate is an effective although technically demanding method of treatment. Complication rates were comparable to existing reports of this treatment method, and appear to be improved over traditional methods of fixation.

Immediate function in the atrophic maxilla using zygoma implants: a preliminary study.

Abstract: Statement of problem Oral rehabilitation of the edentulous atrophic maxilla to allow placement of a fixed dental prosthesis remains a challenge, especially if immediate function is provided. Purpose The aim of this retrospective, preliminary study was to evaluate, after a period of a 6 to 29 months' follow-up of prosthetic loading, the survival rate of 36 immediately loaded zygomatic implants placed in 18 atrophied maxillae. Material and methods Eighteen consecutive patients (6 men and 12 women), with an average age of 58 years (range of 44–74 years), were followed up to 29 months (average of 14 months). The clinical criteria included stability of the implants and the prosthesis, resonance frequency analysis (RFA), and evaluation of swelling, pain, or discomfort. Radiographic analysis was completed for conventional implants, but not for zygoma implants. All patients had a fixed prosthesis screwed onto implants within 48 hours after implant placement. Descriptive statistics were used to analyze the data. Results No zygomatic implants were lost over the observation period. Survival rate was 100% over an average 14-month observation period. Three conventional implants were lost, resulting in a survival rate of 95.6%. All the provisional prostheses were stable, and no relevant complications were noted. Conclusions The use of zygoma implants, together with conventional implants, in severely resorbed maxilla, appears to be a reliable technique for providing immediate function to patients.

Total disc arthroplasty: consequences for sagittal balance and lumbar spine movement

Abstract: This in vivo biomechanical study was undertaken to analyze the consequences for sagittal balance and lumbar spine movement in three different lumbar disc prostheses. A total of 105 patients underwent total disc replacement in three different centers. The Maverick® prosthesis was used in 46 patients, the SB Charite® device was used in 49 patients and the Prodisc® device was utilized in 10 patients. The analysis was computer assisted, using Spineview® and Matlab® softwares. The intra and inter-observer reliability and measurement uncertainty was performed. The analysis of lateral X-ray films in flexion–extension allowed to measure the prosthesis positioning, the range of motion (ROM), the localization of the mean center of rotation (MCR), the vertebral translation and the disc height, for each prosthesis device. The sagittal balance was analyzed on a full spine film. The parameters studied were described by Duval-Beaupere. The results were compared to the data found in literature, and compared to 18 asymptomatic volunteers, and 61 asymptomatic subjects, concerning the sagittal balance. The prostheses allowed an improvement of the ROM of less than 2°. The ROM of L5–S1 prostheses ranged from 11.6 to 15.6% of the total lumbar motion during flexion–extension. At L4–L5 level, the ROM decreased when there was an arthrodesis associated at the L5–S1 level. There was no difference of ROM between the three prostheses devices. The MCR was linked to the ROM, but did not depend on the prosthesis offcentering. The disc height improved for any prosthesis, and decreased in flexion or in extension, when the prosthesis was offcentered. An increase of translation indicated a minor increase of the ROM at L4–L5 level after Maverick® or SB Charite® implantation. The L5–S1 arthrodesis was linked with an increase of the pelvic tilt. The lumbar lordosis curvature increased between L4 and S1, even more when a prosthesis was placed at the L3–L4 level. Total disc arthroplasty is useful in the surgical management of discogenic spinal pathology. The three prostheses studied allowed to retorate the disc height, the ROM, without disrupting the sagittal balance, but induced modification of the lumbar curvature.

Immediate functional loading of implants placed with flapless surgery in the edentulous maxilla: 1-year follow-up of a single cohort study.

Abstract: Purpose: To evaluate success rates and complications of implants placed with a flapless technique and immediately loaded in fully edentulous maxillae. Materials and Methods: Implants were placed in fully edentulous maxillae with a minimum insertion torque of 45 Ncm in underprepared sites to allow maximum stability at insertion using a flapless technique. Implants were immediately loaded. Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, and edema evaluation. Stability of individual implants was assessed both manually and with Osstell at baseline and after 12 months of loading. A single sample t test was used with a significance level of .05. Results: Thirty-three consecutively treated edentulous patients received 202 implants in the maxilla. In 10 patients, 53 implants were immediately inserted in fresh extraction sockets. At implant insertion, a flap had to be elevated to control the direction of the drill in 5 patients. Three implants in 2 patients did not reach sufficient stability and were left to heal for 45 to 90 days. All restorations (21 fixed prostheses and 12 overdentures) were delivered the same day of the surgery. Twenty-six patients experienced no or slight postoperative pain; 7 experienced moderate to severe pain. No or slight edema was recorded for 19 patients and moderate to severe edema for 14 patients. Two implants failed in 2 patients but were successfully replaced the same day they were removed. No major complications occurred. Five patients experienced biologic complications, eg, peri-implantitis; 10 experienced prosthetic complications. No prosthesis failed; however, 1 patient was unsatisfied with his overdenture and requested a fixed alternative. There was a highly significant difference (P < .001) between the stability at implant insertion and after 12 months. Conclusion: Implants placed in the edentulous maxilla with a flapless procedure can be successfully loaded the same day of surgery. INT J ORAL MAXILLOFAC IMPLANTS 2007;22:87–95

Does the type of implant prosthesis affect outcomes for the completely edentulous arch

Abstract: PURPOSE A systematic review, including meta-analysis, was conducted to answer the question "Does the type of implant prosthesis affect outcomes for the completely edentulous arch?" The current paper was to assess the impact of fixed or removable prosthesis type on implant survival and success outcomes. MATERIALS AND METHODS Pertinent literature was identified through December 31, 2005 using a PubMed search strategy and hand-searching of relevant journals, a personal library, and reference lists from included studies. Inclusion and exclusion criteria were applied to the titles and abstracts and subsequently to the full text of included references. The 72 included studies reported oral implant survival or success, crestal bone levels or loss, and/or prosthesis success or maintenance differentiated by arch and by prosthesis type (fixed or removable, splinted or nonsplinted) established either in 1-year randomized clinical trials or 5-year observational studies. RESULTS Statistical analysis revealed only a site-specific rather than a design-specific finding that implant survival for mandibular fixed prosthesis groups had a 6.6% greater implant survival than maxillary fixed prostheses groups (P < .001). The observation of greater implant failure for removable over fixed protheses groups in the maxilla appeared likely due to deficient preoperative bone volume in the removable prosthesis groups. DISCUSSION There is little evidence that implant survival or success is affected directly by prosthesis type based on current designs studied for at least 5 years. Prosthesis maintenance does appear to vary with different prosthesis designs. CONCLUSION While this study suggests implant survival and success may not be affected by variation across the established types of implant prostheses, maintenance demands can vary with implant prosthesis type, especially with overdenture attachments. Clinicians should remain diligent in basing implant prosthodontic technique on established protocols.

Survival analysis and clinical evaluation of implant-retained prostheses in oral cancer resection patients over a mean follow-up period of 10 years

Abstract: Statement of problem Dental implants have been increasingly used for prosthodontic rehabilitation of patients following oral tumor resection and postsurgical radiotherapy. However, only a few long-term studies have examined the implant survival rate and other factors related to prosthodontic treatment in oral tumor resection patients. Purpose The purpose of this study was to evaluate the long-term survival of dental implants and implant-retained prostheses in oral cancer resection patients. Material and methods Ninety-three patients (63 men, 30 women) with a mean age of 59 years (range of 26-89 years) received 435 implants after the resection of a head and neck tumor. Twenty-nine patients received postsurgical radiotherapy prior to implant placement. The factors related to implant survival or failure were monitored over a mean observation period of 10.3 years (range of 5 to 161 months). Prosthodontic rehabilitation was evaluated with respect to the rates of technical failures and complications. Data were analyzed using a Kaplan-Meier curve and comparisons were made with the log-rank test or the Wilcoxon test (a=.05). Results Of the 435 implants, 43 implants were lost; the cumulative survival rate was 92%, 84%, and 69% after 3.5, 8.5, and 13 years, respectively. Twenty-eight implants in 6 patients were counted as lost since the patients had died. Twenty-nine irradiated patients received 124 implants, of which 6 implants were lost prior to prosthodontic rehabilitation. In 68 patients with 78 rigid bar-retained dentures, only minor technical complications were identified. However, all 25 fixed implant-supported restorations had no technical component failures and did not require technical maintenance. Conclusions This study demonstrates that implant-retained and -supported prostheses in oral cancer resection patients, irrespective of the cancer treatment procedure, show lower long-term survival rates than those in patients without prior cancer surgery. Rigid fixation of the implant-supported prosthesis appears to minimize the complication rates. The poor implant survival rate was due to the higher mortality rate among these patients, and not to a lack of osseointegration. (J Prosthet Dent 2007;98:405-410)

Five-year results of implants with an oxidized surface placed predominantly in soft quality bone and subjected to immediate occlusal loading

Abstract: Statement of problem Numerous studies have demonstrated the feasibility and predictability of immediate implant loading or immediate implant restoration. However, most of these studies report primarily short-term outcomes. Purpose The purpose of this prospective clinical study was to document the 5-year outcome of immediate occlusally loaded implants with an oxidized, microtextured surface placed to support fixed prostheses in various regions of the jaws. Material and methods Thirty-eight patients received a total of 51 implant-supported fixed prostheses, 29 mandibular and 22 maxillary, the day of implant insertion. Thirty were fixed partial dentures (FPDs), 20 replaced single teeth, and 1 was a fixed mandibular complete denture. The restorations were supported by 102 slightly tapered, screw-type implants, the majority of which were placed in posterior regions (88%) and primarily in soft bone quality (76%). Patients with ongoing signs of parafunctional habits were not included. All implants were placed using conventional flap procedures. Treatment with local regenerative procedures in connection with implant placement was accepted within the study design. Resonance frequency implant stability measurements and marginal periimplant soft tissue evaluations were conducted. Radiographic examinations were performed at the time of prosthesis insertion, at 1-and 6-month follow-ups, and annually at the 1- through 5-year follow-up visits. This report presents the results after 5 years of loading, summarized with descriptive statistics. Results Three maxillary implants were removed, although stable, in 1 patient at the 8-week follow-up due to postoperative infection in the adjacent guided bone regeneration (GBR) area. No additional implants were lost. This resulted in a cumulative implant success rate of 97.1% after 5 years of prosthetic loading. The mean marginal bone remodeling (SD) after 5 years of function was 1.54 (0.99) mm. At the 5-year examination, absence of marginal plaque and absence of bleeding on probing was reported for 75% and 74% of the sites, respectively, and remained generally unchanged from the 1-month follow-up. Conclusions The 5-year follow-up data indicate that an immediate loading protocol using a slightly tapered implant design with an oxidized, microtextured surface is a successful treatment alternative in regions exhibiting soft bone quality.

Testicular prostheses: development and modern usage.

Abstract: INTRODUCTION Te sticular prostheses produced from various materials have been in use since 1941. The absence of a testicle has been shown to be a psychologically traumatic experience for males of all ages. The indications for insertion of a prosthesis include absence or following orchidectomy from a number of causes such as malignancy, torsion and orchitis. The most common substance used around the world in the manufacture of these implants is silicone; however, in the US, this material is currentl y banned because of theoretical health risks. This has led to the development of saline-filled prostheses as an alternative. PATIENTS AND METHODS A Medline search was carried out on all articles on testicular prosthesis between 1966 and 2006. CONCLUSIONS This review highlights the controversies regarding prosthetic materials, the complications of insertion and the potential benefits of this commonly performed procedure.

Short-term results using Kurz titanium ossicular implants

Abstract: The efficiency of titanium middle ear prosthesis for ossicular reconstruction in chronic ear disease is investigated in a Scandinavian two-center retrospective study from a Norwegian tertiary otology referral center and a Finnish otology referral center. Retrospective chart reviews were performed for procedures involving 73 titanium prostheses between 1999 and 2004. All patients that underwent surgery including the Kurz Vario titanium prosthesis were included in the study, 38 procedures including the partial ossicular replacement prosthesis (PORP) and 35 procedures including the total ossicular replacement prosthesis (TORP). Mean follow-up was 14 months. The ossiculoplasty was performed alone (29 patients) or in combination with other chronic ear surgery procedures (34 patients). Comparisons of preoperative and postoperative pure tone averages (0.5, 1, 2, and 3 kHz) according to AAO-HNS guidelines are presented, as well as data for different PTA definitions. Otosurgery procedures, complications, revisions, and extrusion rates are reported. A postoperative air-bone gap (ABG) of ≤20 dB was obtained in 77% of the patients, 89% for the Bell (Porp) prosthesis, and 63% for the Arial (Torp) prosthesis. Overall mean pure tone averages improved 20.6 dB with ABG improvement of 19.3 dB. The overall extrusion rate was 5% (4 patients). Titanium prostheses have been easy and fast to handle and effective implants for reconstruction of the ossicular chain. We found no difference between reconstruction with or without cholesteatoma surgery during the same procedure. The combination of CWD and Torp gave significant inferior hearing thresholds as compared to Torp/CWU and Porp/CWD combinations.

Bipolar proximal femoral replacement prostheses for musculoskeletal neoplasms

Abstract: While bipolar proximal femoral replacement prostheses (PFRP) have become a common treatment for tumors of the proximal femur, long-term results are not specified in the literature. The objective was to determine the complication and revision rates of bipolar PFRP and compare them to historical controls of bipolar hemiarthroplasties for nontumor indications. Information was retrospectively collected on 62 patients who received bipolar PFRP with cemented diaphyseal stems for primary or metastatic disease of the proximal femur from 1981 to 2003. Mean followup was 5 years. Twelve of 62 (19%) bipolar PFRPs underwent revision. Aseptic loosening was the most common complication with six (10%) undergoing revision. None were converted to THA due to acetabular erosion. Three patients (5%) had problems with dislocation and three (5%) had deep infections. Mean MSTS functional rating was 71% of normal function. The limb salvage rate was 98% and the 5-year event-free prosthetic survival was 79%. Bipolar PFRPs were found to have higher revision, dislocation, and deep infection rates compared to bipolar hemiarthroplasty for nontumor indications, but a lower rate of conversion to THA due to acetabular erosion. Bipolar PFRPs have good long-term durability with some complications, but are able to preserve the limb and provide good function for patients.

The Infected Breast Prosthesis after Mastectomy Reconstruction: Successful Salvage of Nine Implants in Eight Consecutive Patients

Abstract: Background: The use of tissue expanders and permanent implants has an established role in breast reconstruction after mastectomy. Periprosthetic infection, however, represents a known complication. The most conservative approach to severe or recalcitrant prosthetic infection remains removal of the device. However, removal makes subsequent reinsertion and reexpansion more difficult, with less predictable cosmetic results. The authors believe that timely surgical intervention directed toward salvage of infected breast prostheses can be successful, without demonstrating increased capsular contracture. Methods: The authors present nine consecutive cases of infected breast implants (nine implants in eight patients). All patients had previously undergone mastectomy for malignancy and immediate expander/implant reconstruction. Six patients had localized infections that failed to respond to oral antibiotics and two women initially presented with systemic infection. All patients were placed on intravenous antibiotics followed by drainage of fluid, manual debridement and curettage of the infected pocket, device exchange, and postoperative antibiotics. Results: All nine infected breast prostheses responded to this approach and currently remain intact and without recurrent infection. Mean time to follow-up for all patients was 14.6 months (range, 10 to 25 months). Conclusions: In patients with severely infected breast prostheses, timely operative intervention can salvage the previously “unsalvageable” implant; in addition, the surgically replaced implants did not develop severe capsular contractures. Surgical salvage of severely infected breast prostheses after mastectomy is a treatment option that should be considered when dealing with severe or recalcitrant infection in a suitable patient. (Plast. Reconstr. Surg. 120: 581, 2007.)

Cementless CUT femoral neck prosthesis: increased rate of aseptic loosening after 5 years.

Abstract: Background Bone-saving hip arthroplasty techniques, which facilitate revision, are gaining importance as the number of hip replacements in younger patients increases.Patients and methods 123 CUT femoral neck prostheses (ESKA Implants, Lubeck, Germany) were implanted in 113 patients (average age 53 years) between 1999 and 2002. After a mean follow-up of 5 (3–7) years, we determined the state of 120 prostheses; 3 patients could not be located. 97 patients with 107 prostheses, none of which had been revised, were evaluated clinically and radiographically.Results The median Harris hip score improved from 51 points to 92 points in the unrevised hips. 13 CUT prostheses (11%) had been revised, 7 because of aseptic loosening, 3 because of persisting thigh pain, 1 because of immediate vertical migration, and 2 because of septic loosening. The 5-year survival rate of the CUT prosthesis was 89%.Interpretation The medium-term survival with this type of femoral component is unsatisfactory, with a high rate of aseptic ...