Association of periodontal therapy, with inflammatory biomarkers and complications in COVID-19 patients: a case control study.

BACKGROUND: In previous studies, COVID-19 complications were reported to be associated with periodontitis. Accordingly, this study was designed to test the hypothesis that a history of periodontal therapy could be associated with lower risk of COVID-19 complications. METHODS: A case-control study was performed using the medical health records of COVID-19 patients in the State of Qatar between March 2020 and February 2021 and dental records between January 2017 and December 2021. Cases were defined as COVID-19 patients who suffered complications (death, ICU admissions and/or mechanical ventilation); controls were COVID-19 patients who recovered without major complications. Associations between a history of periodontal therapy and COVID-19 complications were analysed using logistic regression models adjusted for demographic and medical factors. Blood parameters were compared using Kruskal-Wallis test. RESULTS: In total, 1,325 patients were included. Adjusted odds ratio (AOR) analysis revealed that non-treated periodontitis was associated with significant risk of need for mechanical ventilation (AOR = 3.91, 95% CI 1.21-12.57, p = 0.022) compared to periodontally healthy patients, while treated periodontitis was not (AOR = 1.28, 95% CI 0.25-6.58, p = 0.768). Blood analyses revealed that periodontitis patients with a history of periodontal therapy had significantly lower levels of D-dimer and Ferritin than non-treated periodontitis patients. CONCLUSION: Among COVID-19 patients with periodontal bone loss, only those that have not received periodontal therapy had higher risk of need for assisted ventilation. COVID-19 patients with a history of periodontal therapy were associated with significantly lower D-dimer levels than those without recent records of periodontal therapy. CLINICAL RELEVANCE: The fact that patients with treated periodontitis were less likely to suffer COVID-19 complications than non-treated ones further strengthen the hypothesis linking periodontitis to COVID-19 complications and suggests that managing periodontitis could help reduce the risk for COVID-19 complications, although future research is needed to verify this.

Impact of Implant and Site Characteristics on the Pattern of Bone Loss in Peri-implantitis.

PURPOSE: To assess the pattern of bone loss in peri-implantitis in partially edentulous patients and relate patient and implant/site characteristics that may influence such patterns. MATERIALS AND METHODS: In this retrospective study, the records of partially edentulous patients with dental implants were stratified according to sex, age, smoking, and diabetes. Implants were stratified according to site, number of years in function, presence of adjacent implants, diameter, bone-grafted site, and implant platform. All these variables were obtained from previous periodontal charts and radiographs. The implants were then classified into two main groups: (1) bone loss as defined by the presence of progressive marginal bone change found on radiographs at least 12 months following prosthesis placement compared to a baseline with a threshold ≥ 2 threads of bone loss; and (2) no bone loss as defined by no detected bone change or bone level change with a threshold < 2 threads. The bone loss group was further divided into three subgroups according to pattern: vertical, horizontal, and combined. Descriptive analyses were applied to assess the frequency of the pattern of bone loss (horizontal, vertical, and combined). A statistical regression model was used to find if there was a significant correlation between patient/implant characteristics and the pattern of bone loss. RESULTS: A total of 304 charts with 540 implants met the inclusion criteria. One randomly selected implant per patient through Microsoft Excel software was included in this study. Of these, 157 (51.6%) of examined charts were men and 147 (48.4%) were women. The patients' mean age was 63.9 ± 11.4 years (range: 27 to 85 years) at implant placement, and implants had been in function for 12 to 120 months (median: 37 months). The percentage of implants that had bone loss was 24.7% (75 out of 304). The pattern of bone loss was 65%, 22%, and 13% for vertical, horizontal, and combined, respectively. Implants that had been placed in surgically bone-grafted sites had increased odds of vertical bone loss with either narrow or wide implants (OR = 2.5 [P = .04] and 3.1 [P = .01], respectively). The presence of adjacent implants had significantly (P = .003) increased odds of horizontal bone loss (OR = 5.1). CONCLUSION: Approximately one-quarter of dental implants (24.7%) developed bone loss beyond normal physiologic remodeling. Vertical bone loss around single implants was the most common pattern (65%), particularly around implants placed in bone-grafted sites with odds ratio of 2.5 for narrow implants vs 3.1 for wide implants. In the presence of adjacent implants, the odds of horizontal bone loss was 5.1 (P = .003).