A simplified method to assess precision of fit between framework and supporting implants. A preliminary study

Purpose: To present a simplified method for assessment of precision of fit between screw-retained frameworks and supporting implants in clinical situations. Materials and Methods: Torque-angle signature analysis is a method for analysis of tension within a joint. The OsseoCare device developed by Nobel Biocare was utilized for the tests. Three titanium frameworks were fabricated on the same master cast according to 3 different methods: (1) 1-piece casting, (2) the CNC (computer numeric controlled) method, and (3) the CTiP (Cresco Ti Precision) method. These frameworks were used to test the device and indirectly the application of the torque-angle signature analysis technology. Results: The frameworks fabricated according to the CNC and CTiP methods demonstrated OsseoCare tracings similar to the reference models of passively fitting joints, while the 1-piece cast framework did not. Conclusion: According to this pilot study, the OsseoCare device and torque-angle signature analysis proved to be feasible for clinical assessment of fit between frameworks and supporting implants

Maxillary sinus elevation with an alloplastic material and implants: 11 years of clinical and radiologic follow-up

Purpose: The aim of this retrospective study was to determine the clinical and radiologic results, over an 11-year period, of resorbable hydroxyapatite used as a bone substitute in maxillary sinus elevation. Materials and Methods: Between 1996 and 2007, we treated 26 patients with maxillary sinus elevation (27 sinuses) using resorbable hydroxyapatite and simultaneous insertion of 47 titanium implants. Patients were recruited, screened, and accepted or rejected sequentially based on specific inclusion/exclusion criteria. Ten months later, 2-stage surgery and prosthetic rehabilitation were performed. Results: During the 11-year follow-up period (mean, 6 years), all the implants appeared clinically and radiologically integrated. The cumulative survival rate was 100%. During the observation period, the resorption of the graft apically to the implant was 1.8 mm on average. Conclusion: The posterior area of the maxilla often represents a challenging clinical situation because of either the lack of alveolar bone or the structural characteristics of the trabeculae in that specific area. The high survival rate of the implants and the stability of the mineralization of the graft confirmed that resorbable hydroxyapatite was a suitable material for sinus grafting

Soft tissue stability with immediate implants and concave abutments

Implant therapy success in the anterior maxilla is judged not only by osseointegration, but also by having sound and stable peri-implant tissues that appear identical to the gingiva surrounding the healthy adjacent teeth. The creation of predictable peri-implant esthetics requires proper preservation of the osseous and soft tissues surrounding the failing teeth, proper three-dimensional implant placement, and proper understanding of prosthetic management. It is now possible to place immediate implants and immediate prostheses to improve esthetics and to simplify treatment, but this technique does not seem to have a stable long-term buccal mucosa. To avoid or reduce this negative effect it appears to be important to increase the thickness of the buccal tissues, and to use appropriate implant components. The aim of the present retrospective study was to observe the dimensional alterations of the peri-implant tissues after immediate implants and single-tooth restorations with concave abutments performed on 28 patients, with a mean followup time of 20.4 months

Maxillary sinus floor augmentation with vegetal hydroxyapatite “versus” demineralized bovine bone : a randomized clinical study with a split-mouth design

Purpose: The objective of this paper was to compare histologically and histomorphometrically a hydroxyapatite originated by algae (Algipore) versus demineralized bovine bone (Bio-Oss Geistlich Pharma, Wolhusen, Switzerland) utilised as bone substitutes in maxillary sinus floor elevation with a split-mouth design. Materials and Methods: Five healthy patients underwent a bilateral maxillary sinus floor elevation procedure under local anesthesia. In each case, residual posterior maxillary bone height was between 2 mm and 5 mm. The original bone was augmented with a split-mouth design with 100% Algipore on the test side and 100% Bio-Oss on the contralateral control side. After a healing period of 6-8 months during the re-opening surgery biopsies were retrieved and Xive Implants (Dentsply Implants, Mannheim, Germany) were placed. Results: At microscopic level both Bio-Oss and Algipore blocks resulted well osseointegrated, without inflammatory infiltrate, with an high level of mineralization, without gap between the bone and biomaterial interfaces that resulted indistinguishable. A close contact between the two faces was observed without the presence of slits. Histomorphometrical analysis showed that, on average, the percentage of medullary space was higher for the Bio-Oss compared with Algipore (38.61% \ub18.90% vs. 29.23% \ub17.89%). In contrast, the mean value of residual particles of biomaterials was higher in Algipore than in Bio-Oss specimens (42.86% \ub118.61% vs. 22.30% \ub16.40% respectively). Conclusions: The data confirmed that sinus lift carried out with Algipore performed in a similar way of that carried out with Bio-Oss and that this material is safe, predictable and without invasiveness

Granular deproteinized bovine bone for horizontal ridge augmentation: a non-conventional clinical technique (Impiego di osso bovino deproteinizzato granulare negli incrementi orizzontali: presentazione di una tecnica non convenzionale)

none4noneRedemagni M; Garlini G; Orsini G; Rossini FRedemagni, M; Garlini, G; Orsini, Giovanna; Rossini, F

Bone resorption around dental implants placed in grafted sinuses: clinical and radiologic follow-up after up to 4 years

Purpose: The long-term results of endosseous implants depend on the maintenance of bone support. The aim of this study was to evaluate radiologically bone resorption around dental implants placed in grafted sinuses after up to 4 years of function. Materials and Methods: Between 1997 and 2001, augmentation of the maxillary sinus floor with alloplastic (Biostite) or xenogenic (Bio-Oss) materials was performed in 34 patients. Results: Eighteen patients participated in the study. Twenty-six sinus augmentations were performed on these 18 patients, and they received 37 implants. The change in marginal bone level around the implants at the mesial side was 1 mm during the first year after the abutment connection, followed by an annual loss of 0.1 mm. The change in marginal bone level around the implants at the distal side was 1.1 mm during the first year after the abutment connection followed by an annual loss of 0.2 mm. Discussion: The implant survival rate observed in this study is in line with data previously reported for patients treated with implants in the posterior maxilla without bone atrophy. The results for implants placed into sinuses grafted with Bio-Oss were similar to the results for implants placed in sinuses grafted with Biostite. Conclusion: Although this study involved a limited number of procedures, it confirmed that alloplastic and xenogenic materials can be reliable for bone regeneration in subantral cavities. The angular defects present both at the distal and mesial sides of the implants were comparable to those observed at implants placed in native bone