Implant Dentistry最新文献

Objective: To evaluate the long-term incidence of complications in abutment teeth and dental implants in periodontally treated and maintained patients, refusing bone grafting surgical therapies, rehabilitated with full-arch telescopic-retained retrievable prostheses (TRPs) and full-arch fixed prosthesis (FPs), both supported by teeth-implants combination.

Materials and methods: After active periodontal therapy, 18 patients were rehabilitated with full-arch TRPs, whereas 17 patients were rehabilitated with full-arch FPs. Patients were annually evaluated for technical and/or biological failures/complications.

Results: During the 15-year observation period, 6 of 164 (3.6%) implants failed and 19 of 233 teeth were extracted (9.2%) in the TRPs group, whereas 6 of 152 (3.9%) implants failed and 23 of 221 (10.4%) abutment teeth were extracted in the FPs group. Differences in implant failures and abutment teeth loss between the 2 groups were not statistically significant. In both the groups, Cox regressions identified significant difference (P < 0.05) for mean initial bone loss, aggressive periodontitis, and smoking, as factors contributing to tooth loss and implant failures in general.

Conclusion: In periodontally treated patients, refusing bone grafting surgical therapies, rehabilitated with full-arch TRPs and full-arch fixed prostheses, both supported by teeth-implants connection, high survival rates can be expected if regular supportive periodontal therapy had been performed.

Objective: To assess the potential of using autologous demineralized tooth matrix (aDTM) in combination with platelet-rich fibrin (PRF) membrane (aDTM/PRF) or PRF membrane alone (control) to preserve the ridge dimension and facilitate bone healing after tooth extraction.

Materials and methods: Forty premolar sockets were assigned to either the aDTM/PRF or control group. Horizontal and vertical ridge changes were evaluated at the baseline 2, 4, 6, and 8 weeks using cast-based and periapical radiographs.

Results: aDTM was well tolerated in all sites without incidences of postoperative complication. The change in horizontal ridge width was significantly greater in the control compared with the aDTM/PRF group. The overall vertical marginal bone resorption on the mesial, distal, and central site in the aDTM/PRF group was not statistically different from the control group. During the first 6 weeks, the bone healing density in the aDTM/PRF group was significantly higher than that of the control group, then it converged at week 8.

Conclusion: Application of aDTM with PRF membrane is useful for ridge preservation by reducing the horizontal ridge collapse and promoting bone healing as shown clinically and radiographically.

Objectives: Tooth-to-implant-connected prostheses have been described as a possible treatment option for patients with long-span edentulous situations that were not conducive for placement of an adequate number of supporting implants. In this comprehensive overview of systematic reviews, the incidence of complications and the long-term survival rates of tooth-to-implant-supported fixed partial dentures (FPDs) were evaluated to determine whether it is a viable treatment.

Materials and methods: A systematic search of 5 electronic databases was conducted for systematic reviews and meta-analyses of tooth-to-implant-supported FPDs up to January 2017. The articles were AMSTAR rated for methodological quality, and low-quality articles were eliminated.

Results: The initial search yielded 369 reviews in PubMed, 248 in Web of Science, 49 in EMBASE, 63 in Cochrane Library, and 27 in Google Scholar. After removal of duplicates and after full-text analysis, 5 were selected for the overview.

Conclusions: Within the limitations of this overview, it was concluded that (1) the 10-year survival rates for tooth-to-implant FPDs were lower than the 5-year survival rates, (2) the tooth-to-implant FPDs' survival was lower than the individual abutment tooth or implant supporting it, (3) the biological and technical complications were more at 10 years compared with 5 years, and (4) the intrusion of the abutment teeth was more in the nonrigid connection FPDs than the rigid connection FPDs. Therefore, tooth-to-implant FPDs are a viable option but should be considered secondary to other available options with higher long-term survival rates and lower complications.

Purpose: The purpose of this study was to evaluate the influence of the implant-abutment connection type on the bone level around dental implants in long-term observation and the survival rate for the different types of implant-abutment connections.

Materials and methods: Two groups of implants made of titanium grade 23 alloy and with sandblasted and acid-etched (SLA) surface were included in the study: (a) the internal hex implant-abutment connection group (480 SPI dental implants; Alpha-Bio Tec, Petach Tikwa, Israel, 184 patients) and (b) the internal cone implant-abutment connection group (60 C1 dental implants; MIS Implant Technologies, Shlomi, Israel, 34 patients). Certain inclusion and exclusion criteria were applied. Marginal bone loss (MBL) around the dental implants was measured in intraoral radiographs taken with parallel technique with a film holder and by bite recording index. X-rays were performed at the moment of functional loading, and at 12, 24, 36, and 60 months after loading. The digital analysis was conducted using Dental Studio 2.0 computer software.

Results: Average MBL was significantly lower in the conical connection compared with internal hex group-0.68 ± 0.59 versus 0.99 ± 0.89 mm (12 months), 0.78 ± 0.80 versus 1.12 ± 1.00 mm (24 months), 0.83 ± 0.87 versus 1.22 ± 1.03 mm (36 months), and 0.96 ± 1.02 versus 1.30 ± 1.15 mm (60 months after loading). Both groups of implants achieved a 100% survival rate.

Conclusion: The internal cone connection reduced bone resorption compared with the internal hex. Both groups of implants had a 100% survival rate.

Objectives: The aim was to investigate the in vivo efficacy of a cancellous particulate allograft bone in the regeneration of postextractive atrophic sites.

Material and methods: Ten patients were selected, and after a minimally invasive extraction of the teeth (T0), a cone beam computed tomography was performed (T1). Seven days after extraction, Puros cancellous particulate homologous graft was inserted into the elected sites together with a membrane (T2). After 4 months, a cone beam computed tomography of the sites was performed (T3). After 5 months, samples of the regenerated sites were taken contextually to implant insertion (T4). The samples were histologically and histomorphometrically analyzed. Intraoral periapical radiographs were accomplished at T4 and at the 6-year follow-up appointment (T5).

Results: The mean vertical bone augmentation was of 4.1 mm in the lower jaw and of 3.35 mm in the maxilla at T3 appointment. The mean horizontal bone augmentation in the lower jaw was 2.02 and 2.15 mm in the maxilla. At T4, the mean total bone was 60.01% and the mature bone was 98.41. At the 6-year follow-up visit, the mean periimplant bone resorption was 0.14 mm (range 0-0.5 mm).

Conclusions: Cancellous particulate allograft bone demonstrated excellent bone regeneration behavior both in terms of quantity and quality, and stable results over a 6-year period.

Clinical relevance: Cancellous allograft bone can be successfully used to regenerate atrophic sites.

Purpose: The purpose of this case series was to investigate treatment outcomes of maxillary sinusitis associated with peri-implantitis at sinus floor augmented sites for a 3-year follow-up.

Materials and methods: Eighteen implants in 8 patients diagnosed with maxillary sinusitis associated with peri-implantitis were reviewed. Four patients were treated with implant removal and antibiotics, and 4 patients were treated with implant removal, the modified Caldwell-Luc operation (CLOP), and antibiotics. Seven patients, who had 7 survived implants, were followed up to 3 years after treatment. The characteristics between failed and survived implants were compared. Radiographic parameters of survived implants were analyzed using the Friedman test.

Results: Eleven failed implants from 8 patients exhibited approximately 10-mm pocket depths and mobility at diagnosis. Seven survived implants from 7 patients exhibited no significant changes in crestal bone loss at the facial side for 3 years after the treatments. Sinus mucosal thickening was significantly reduced during the 3-year follow-up after the treatments.

Conclusion: The progression of peri-implantitis in sinus floor augmented sites may lead to maxillary sinusitis. To confirm the efficacy of the intraoral approaches, such as the modified CLOP, systematic clinical studies with a large sample size and a long-term follow-up should be conducted.

Introduction: The aim of this study is to investigate the effects of Concentrate Growth Factors Extract (CGF-e) on the proliferation and osteogenic differentiation of MC3T3-E1 cells under high glucose condition.

Materials and methods: MC3T3-E1 cells were divided into 4 groups including normal glucose (5.5-mM) group (control), high glucose (25.5-mM) group, normal glucose + CGF-e group, and high glucose + CGF-e group. The proliferation, osteogenic differentiation and mineralization of osteoblasts were evaluated, respectively, by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, cytoskeleton analysis, alkaline phosphatase activity assay, alizarin red staining, and real-time polymerase chain reaction. Western blots analysis was used to explore the role of PI3K/Akt pathway.

Results: The viability, osteogenic differentiation, and mineralization of MC3T3-E1 cells were significantly decreased by high glucose. All observed osteogenic dysfunction were inhibited by CGF-e. Moreover, the PI3K/Akt pathway was activated by CGF-e.

Conclusions: It was concluded that the soluble factors released by CGF could significantly attenuate high glucose-mediated MC3T3-E1 cells osteogenic dysfunction through the PI3K/Akt pathway.