A Multicenter Cohort Study on 301 Tissue-Level Implants: Cumulative Implant Survival Rate and Marginal Bone Level Change up to 4.5 Years.

PURPOSE: To retrospectively determine the cumulative survival rate (CSR) and marginal bone level change (ΔMBL) around novel hybrid design tissue-level (TL) dental implants that support multiple-screw-retained restorations. MATERIALS AND METHODS: Implant CSRs were analyzed at the implant and patient level using Kaplan-Meier estimates. ΔMBL was measured by comparing the periapical loading and follow-up visit radiographs using an improved standardized digital methodology based on image gray levels. ΔMBL outcomes were subject to linear mixed regression to identify potential risk factors. RESULTS: A total of 301 TL implants in 69 patients with an average age of 62.6 ± 11.7 years (range: 36 to 87 years) at the time of implant placement were considered for the analysis. All 301 implants were successfully restored and loaded. The 54-month CSRs at the implant and patient levels were 98.9% (95% CI: 96.7 to 99.6) and 95.3% (95% CI: 86.1 to 98.5), respectively. ΔMBL after a mean follow-up of 22 ± 10.7 months after loading was 0.00 ± 0.57 mm. None of the implant sites showed marginal bone loss exceeding 1.5 mm. Multivariate regression analysis revealed a significant association between ΔMBL and the loading protocol (P = .027) but not between ΔMBL and age or transgingival height. CONCLUSIONS: The high CSRs and stable peri-implant marginal bone levels support the use of recent TL implants, which have a hybrid design inherited from the bone-level implant-abutment connection, as a suitable treatment option for restoring partially or fully edentulous patients with a good mid-term prognosis. These results should be complemented by further prospective studies in a real-world multicenter private practice setup that represents the daily realities of implant treatment.

Periodontal Diseases and COVID-19: A Scoping Review.

The aim of this scoping review was to present the existing literature regarding the relationship between periodontal diseases and coronavirus disease 2019 (COVID-19). The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) extension for scoping review guidelines was followed. Articles were retrieved from PubMed/MEDLINE and Scopus databases and screened to include studies relating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) or COVID-19 to periodontal cells and/or tissues and/or diseases. Twenty-five papers were included; consisting of six reviews, seven original articles, six short reports, four letters to the editor, one commentary, and one case report. The articles were allocated to three different topics: (i) hypotheses on the relationship between periodontal diseases and COVID-19; (ii) risk factors and comorbidities common to periodontitis and COVID-19; (iii) periodontal manifestations of COVID-19. Certain molecules (angiotensin-converting enzyme-2, furin, cathepsin, TMPRSS2...) that are found at a high level in periodontal tissues, particularly in patients with periodontitis, are involved in the mechanism of entry of SARS-CoV-2 into cells. Periodontopathic bacteria could also play a direct role in the mechanism of entry of SARS-CoV-2 by cleaving the S-protein, and the cytokines produced during periodontitis could add to the cytokine storm found in the severe forms of COVID-19. It thus appears that the treatment of periodontitis, which allows a reduction in periodontopathic bacteria and of the local and systemic inflammation state, could be part of a strategy to prevent the development of severe forms of COVID-19.

Histologic and histomorphometric evaluation of new zirconia-based ceramic dental implants: A preclinical study in dogs.

OBJECTIVE: Healing of soft tissues and improvement of aesthetics have become major research objectives in implantology and renewed the interest for ceramics implants. The aim of this study was to evaluate the pre-clinical performance of screw-shaped sandblasted-etched implants processed from an innovative zirconia-based ceramic composite, in comparison to titanium. METHODS: Twenty-four ceramic and twenty-four titanium screw-shaped sandblasted-etched dental implants were tested in a split-mouth design in six Beagle dogs. Surface topographies were investigated by confocal microscopy. Local tissue effects were evaluated at 4 and 13 weeks after implantation through histology. An ANOVA statistical analysis (5% risk; p < 0.05) was performed to compare peri-implant quantitative histomorphometric parameters on buccal and lingual sides, including Bone to Implant Contact (BIC) among test groups and time-periods. RESULTS: Titanium and ceramic implants presented respectively moderate and minimal roughness. After 4 and 13 weeks, ceramic implants showed an inflammatory tissue response close to titanium implants. At both period of time there was no significant difference between the titanium and ceramic groups in terms of BIC values (mean ± SD) at the lingual or buccal sides or when combining buccal + lingual BIC values (respectively for titanium and ceramic, 68.4 ± 14.7 % and 75.0 ± 13.5 % at 4 weeks, and 92.0 ± 8.6 % and 86.1 ± 13.8 % at 13 weeks). SIGNIFICANCE: Within the limits of the present study, it can be concluded that newly developed zirconia-based ceramic composite dental implants have similar biocompatibility and osseointegration to those observed in titanium implants. These pre-clinical results corroborate the potential for the use of these new zirconia-based ceramics in oral implantology.

Methodological Proposal to Assess Gingival Thickness in Children.

PURPOSE: Inadequate gingival thickness (GT) may lead to gingival recession. Thus, early identification of patients/teeth at risk would be advantageous. In adults, the probe's visibility through the marginal gingiva (reference test) has been considered a reliable criterion to describe a thin gingiva. This study aimed to evaluate in children two more convenient methods: the whitening of the attached gingiva with coronal labial traction (GW test) and the visibility of the gingival blood supply (BS test). MATERIALS AND METHODS: In 69 children, the GT of primary and/or permanent central and lateral incisors, first primary molars and/or first premolars was assessed with the three tests. The sensitivity and specificity of the GW and BS tests and their odds ratio with probing were calculated. RESULTS: According to probing, 39% of children in the studied population had thin gingiva. The GW and BS tests reported different percentages of GT compared to probing, except for primary teeth, maxillary permanent incisors and mandibular first premolars, where the GW test exhibited a comparable percentage. The sensitivity of GW and BS tests was 37% and 19%, respectively, when compared to probing, while the specificity was 84% and 96%, respectively. CONCLUSION: The GW and BS tests could be used for first-line diagnosis of thin gingiva; if the results are negative, probing should be implemented.