Long-Term Observation of Post Copings Retaining Overdenture Prostheses.

PURPOSE: To investigate the long-term (up to 20 years) outcomes of customized post copings (PC) and to evaluate potential factors influencing the risk for complications. MATERIALS AND METHODS: Patients treated with PC-retained overdenture prostheses (OD) in a university setting were selected. Data collected included dental and periodontal parameters, periapical radiographs, and assessment of the OD design. Patient-reported satisfaction levels were evaluated using visual analog scales (VAS), and 20-year cumulative survival and success rates were calculated. RESULTS: A total of 73 patients with 81 ODs and 152 PCs were included. PC survival rate was 80.9%, and the success rate amounted to 64.5% after a mean observation period of 105.4 (± 67.9; range: 6 to 240) months. The 5-year cumulative PC rates were 91.5% for survival and 79.3% for success. Activation of matrices was more frequent with ball attachments than with cylindrical retention (odds ratio [OR] 0.43; 95% confidence interval [CI] 0.2 to 0.94; P = .034). Cylindrical retention was rated significantly better at 96% (interquartile range [IQR] 89.5% to 100%) compared to ball attachment at 88% (IQR 79% to 98.2%; P = .012). The risk for PC complications was higher for OD designs with coverage of the periodontal tissues compared to open designs (OR 0.34; 95% CI 0.15 to 0.78; P = .010). CONCLUSION: Customized PCs on natural abutment teeth for the retention of ODs are a valid treatment in partially dentate patients. Correct prosthesis design and integration into a regular dental hygiene program are mandatory factors for long-term success.

Membrane perforation rate in lateral maxillary sinus floor augmentation using conventional rotating instruments and piezoelectric device-a meta-analysis.

OBJECTIVES: Maxillary sinus augmentation (MSA) is a successful and predictable intervention with low complication rates. Perforations of the Schneiderian membrane may occur impairing the general success. The aim of this study was to compare the incidence of membrane perforations between conventional rotating instruments and piezoelectric devices in a meta-analysis. MATERIAL AND METHODS: An electronic research on MEDLINE and PubMed database was performed evaluating the literature from 1980 till 2016. Meta-analysis was performed with the studies matching the inclusion criteria. The incidence of perforations between conventional and piezo during the lateral maxillary sinus floor elevation was determined, and forest plots and a t test for significance analysis were performed. RESULTS: The search provided 377 articles of which 69 could be included. Selected non-randomised and non-controlled prospective and retrospective studies were incorporated. Conventional rotary instruments were associated with a perforation rate of 24%, the piezoelectric devices with 8% with statistically significant difference between both modalities (p < 0.05). CONCLUSION: Membrane perforations in MSA may be significantly reduced applying piezoelectrical devices for MSA.