Saliva

Peri-implantitis, a common biological complication of dental implants, is characterized by soft-tissue inflammation and progressive bone loss. Oxidative stress is increasingly implicated in its pathogenesis, yet the diagnostic potential of salivary redox biomarkers remains unclear. This study's objective was to assess the association between salivary malondialdehyde (MDA) and total antioxidant capacity (TAC) and peri-implant disease via a pre-registered, quantitative meta-analysis of previously published studies using predefined statistical criteria. Following a priori PROSPERO registration, we systematically searched PubMed, Scopus, and Web of Science (2004-September 2025), extracted data in duplicate, and pooled effects using random-effects models; certainty of evidence was appraised with GRADE (Grading of Recommendations Assessment, Development and Evaluation) and risk of bias with ROBINS-I (Risk Of Bias In Non-randomized Studies of Interventions)/QUADAS-2 (Quality Assessment of Diagnostic Accuracy Studies-2). Twelve studies were included qualitatively: seven (n = 726) contributed to MDA and five (n = 485) to TAC meta-analyses. Peri-implant disease was associated with elevated MDA (SMD = 1.64, 95% CI 1.39-1.88) and reduced TAC (SMD = -1.88, 95% CI -2.17 to -1.58); statistical heterogeneity was not detected, and results were robust to sensitivity and exploratory assay-based subgroup analyses. Salivary MDA and TAC show consistent, large, standardized differences in peri-implant disease; however, observational designs, assay variability, and the absence of validated diagnostic thresholds warrant cautious interpretation and prospective validation before clinical adoption.

ObjectivesThe increasing prevalence of metabolic syndrome (MetS) and periodontitis, both marked by chronic inflammation that disrupts immune function, underscores the need for tailored healthcare approaches that account for their systemic inflammatory impact. The study aimed to estimate and compare the diagnostic accuracy of aMMP-8 expression in oral rinse, saliva, and GCF (gingival crevicular fluid) among patients with periodontitis and those with and without MetS.Materials and methodsA pilot sample of 77 participants was categorized into three groups based on the 2018 AAP/EFP periodontitis classification and the 2006 IDF metabolic syndrome criteria: MetS with periodontitis (MetS-PD; n = 34), systemically healthy with periodontitis (SH-PD; n = 21), and healthy controls (SH-PH; n = 22). Active metalloproteinase-8 (aMMP-8) levels in oral biofluids were quantified using an enzyme-linked immunosorbent assay. ANOVA and ROC curve analysis were done to assess diagnostic accuracy across groups.ResultsaMMP-8 levels varied by group but remained consistent across biofluids, with lower levels in SH-PH and higher levels in SH-PD and MetS-PD (p ConclusionOral rinse may be a preferable matrix for diagnosing periodontal disease, particularly in patients with systemic conditions, compared to saliva and GCF. Prospective longitudinal studies are required to evaluate its utility for monitoring over time.Clinical relevanceThis study highlights the potential of aMMP-8 as a reliable biomarker for assessing periodontal disease severity in patients with MetS, utilizing non-invasive oral fluids. With oral rinses demonstrating high diagnostic accuracy, they may be an effective and accessible tool for screening and case-finding in medical and dental settings in patients with MetS, facilitating early detection and tailored management strategies. aMMP-8 immunoassay chair-side kit offers a practical alternative to traditional methods for screening patients in non-dental settings.

BackgroundAlthough periodontitis and oral microbiota are linked to cardiometabolic diseases (CMD), it is unclear if they similarly predict CMD mortality. We compared the predictive ability of salivary microbiota and periodontal disease measures for CMD mortality in the National Health and Nutrition Examination Survey (NHANES).MethodsWe included 5,037 adults aged ≥30 years (mean age [± standard deviation (SD)]: 48[± 14]; 50% male) from the 2009-2010 and 2011-2012 NHANES cycles. We used 16S rRNA sequencing data from saliva to operationalize microbial composition and diversity. We calculated the relative abundance log-ratio of Treponema (linked with periodontal disease) to Corynebacterium (linked with periodontal health) to compute the Microbial Indicator of Periodontitis (MIP). Interproximal periodontal probing depth and clinical attachment loss were measured from periodontal examinations. Mortality was ascertained through 2019. Survey-weighted Cox models regressed mortality rates on MIP, microbial diversity, and periodontal measures to estimate hazard ratios and 95% confidence intervals (HR [95% CI]).ResultsOver 8.8 median follow-up years, there were 81 CMD and 267 all-cause deaths. After multivariable adjustment, MIP was associated with increased CMD mortality risk (HR per 1-SD: 2.10 [1.30-3.38]). Neither microbial diversity nor periodontitis measures were associated with CMD mortality. MIP was associated with periodontitis in multivariable modeling (risk ratio per 1-SD: 1.29 [1.22-1.39]).ConclusionsIn a nationally representative cohort, greater baseline salivary Treponema to Corynebacterium ratio predicted increased CMD mortality risk, while microbial diversity metrics and periodontal parameters were not significantly associated with CMD mortality. Longitudinal studies that further contextualize the oral microbiota are warranted.Plain language summaryBacteria in the mouth that cause gum disease are linked to cardiometabolic diseases (e.g., diabetes, cardiovascular disease, kidney disease). However, it is not well understood if bacteria of the mouth can predict the risk of death due to cardiometabolic diseases. We used data from a nationwide survey of US adults to explore whether bacteria from saliva, collected from a single time point, are associated with the future risk of cardiometabolic disease death. We found that people with higher levels of gum disease bacteria were more likely to die from cardiometabolic diseases. Future studies are needed to better understand the role of gum disease bacteria in the development of cardiometabolic diseases and the risk of death.