Shortened Treatment Time for Maxillary Sinus Grafting with Simultaneous Implant Placement: Retrospective Analysis with 10-Year Follow-Up.

PURPOSE: The aim of the present retrospective clinical study was to evaluate the outcome of a maxillary sinus lateral window augmentation protocol, which sought to shorten the treatment time. MATERIALS AND METHODS: This protocol entailed sinus augmentation with deproteinized bovine bone minerals (DBBM) and simultaneous implant placement in patients with minimal residual bone height. A total of 89 sinus augmentation procedures were performed in 74 patients, in whom 160 implants were placed between 2005 and 2013. The mean residual bone height was 2.6 ± 0.6 mm. The healing time before loading was 4.18 ± 0.63 months. RESULTS: In a first evaluation in 2014 the early implant survival rate (EIsR) was 96.8% after a mean period of 5.4 ± 2.2 years. A second evaluation in 2019 after a mean period of 10.4 ± 2.2 years showed a late implant survival rate (LIsR) of 83.1%. The failures after 2014 were all caused by peri-implantitis, which affected 14.6% and 16.8% of patients and implants, respectively. This prevalence of peri-implantitis does not appear to be higher than that usually observed in nonaugmented sites. CONCLUSION: This reduction in the duration of treatment compared to the usual duration of 9 to 12 months does not seem to affect the predictability of the technique.

Peri-implantitis-associated methanogens: a preliminary report.

Methanogens have already been described in periodontitis but not in peri-implantitis. Thirty peri-implantitis samples and 28 control samples were collected in 28 consenting peri-implantitis patients. PCR-sequencing of the 16S rRNA gene was used as a broad-spectrum screening method and results were further confirmed by real-time quantitative PCR targeting the mcrA genes. Results showed a methanogen community dominated by Methanobrevibacter oralis in 31/58 (51%) samples including 16/28 (57%) control samples and 15/30 (50%) peri-implantitis samples. Methanobrevibacter massiliense was detected in 5/58 (8.6%) samples including 3/28 (1%) control samples and 2/30 (6.7%) peri-implantitis samples. The prevalence of M. oralis or M. massiliense did not significantly differ in peri-implantitis and control samples (exact Fisher test, P = 0.61 and P = 0.67, respectively). Further ponderation of the methanogen load by the real-time quantitative PCR for actin human gene again indicated non-significant difference (Wilcoxon-Mann-Whitney test, P = 0.48 and P = 0.40, respectively). These data show that the prevalence of methanogens does not differ in peri-implantitis lesions and healthy sites, when individuals are their own control. These data do not allow assigning a specific pathogenic role to methanogens in peri-implantitis; methanogens rather are part of the commensal and normal flora of the oral cavity.