Fernanda Vieira Ribeiro

Aim This study evaluated the impact of the partial exposition of the nonabsorbable membrane (dPTFE) on microbial colonization during bone healing. Materials and Methods Patients indicated for tooth extraction were randomized to dPTFE group (n = 22) - tooth extraction and alveolar ridge preservation (ARP) using an intentionally exposed dPTFE membrane and USH group (n = 22) - tooth extraction and unassisted socket healing. Biofilm samples were collected at the barrier in the dPTFE and on the natural healing site in the USH after 3 and 28 days. Samples from the inner surface of the dPTFE barrier were also collected (n = 13). The microbiome was evaluated using the Illumina MiSeq system. Results Beta diversity was different from 3 to 28 days in both groups, and at 28 days, different microbial communities were identified between therapies. The dPTFE was characterized by a higher prevalence and abundance of gram-negative and anaerobic species than USH. Furthermore, the inner surface of the dPTFE membrane was colonized by a different community than the one observed on the outer surface. Conclusion Intentionally exposed dPTFE membrane modulates microbial colonization in the ARP site, creating a more homogeneous and anaerobic community on the inner and outer surfaces of the membrane. Clinical relevance DPTFE promoted faster biofilm colonization and enrichment of gram-negative and anaerobes close to the regenerated site in the membrane’s inner and outer surfaces. dPTFE membrane can be used exposed to the oral site, but approaches for biofilm control should still be considered. The study was retrospectively registered at Clinicaltrials.gov (NCT04329351).

Diabetes Mellitus (DM) is identified as an important condition that leads to implant complications, and the apico-coronal position and the prosthetic abutment seem to interfere with peri-implant tissue behavior This study aimed at assessing the effect on peri-implant parameters after implant loading of two different methodologies in type two diabetics patients (T2DM) who received implant muco-retained overdentures. Twenty-two mandibular edentulous T2DM received two implants: Test group: prosthetic abutment of a diameter smaller than the platform of the implant and a morse taper subcrestal implant level; Control group: prosthetic abutment of diameter identical to the platform and hexagonal external implant placed at crestal bone level. Clinical, inflammatory, and tomographic evaluations were performed at baseline (after prosthesis installation), and twelve and twenty-four months after implant loading. Test implants presented inferior probing depth and clinical attachment level compared to control at baseline and 12 months (p < 0.05). Test implants presented reduced levels of pro-inflammatory cytokines at 24 months compared to the control implants (p < 0.05). The control group had more changes in bone parameters from baseline to the first and second years (p < 0.05). The test group resulted in reduced bone remodeling and better clinical conditions and positively modulated peri-implant immunoinflammatory molecules. Trial identification UTN code: U1111-1239-3638.