Meta-analysis of oral microbiome reveals sex-based diversity in biofilms during periodontitis.

Sex is an often overlooked, yet compulsory, biological variable when performing biomedical research. Periodontitis is a common yet progressively debilitating chronic inflammatory disorder affecting the tissues supporting teeth that ultimately leads to tooth loss if left untreated. The incidence of periodontitis is sex biased, with increased prevalence in males compared with females but with unknown etiology. We performed a sex-specific meta-analysis using publicly available oral microbiome data from different sampling sites of patients with periodontitis and periodontally healthy controls; sex balance was established for each periodontal health condition. Our results show sex-based diversity in oral biofilms of individuals with periodontitis but not in their saliva, with increased abundance of several periodontal pathogens in subgingival plaques from females compared with males. We devised a quantitative measure, uniquely defined as the Microsexome Index (MSI), which indicates that sexual dimorphism in subgingival bacterial composition is a distinct feature of reduced microbial diversity during periodontitis but not under healthy conditions. In addition, we found that smoking exacerbates microsexome diversity in supragingival biofilms, particularly during periodontitis. Taken together, we provide insights regarding sex-based diversity in periodontitis, a disease with multiorgan associations, and provide the rationale for further mechanistic, diagnostic, and therapeutic studies.

Association between metabolic syndrome components and gingival bleeding is women-specific: a nested cross-sectional study.

BACKGROUND: Metabolic syndrome (MetS) is a cluster of atherosclerotic risk factors that increases cardiovascular risk. MetS has been associated with periodontitis, but the contribution of single MetS components and any possible sexual dimorphism in this relation remain undetermined. METHODS: Using the third National Health and Nutrition Examination Survey (NHANES III), we performed a nested cross-sectional study to test whether individuals aged > 30 years undergoing periodontal evaluation (population) exposed to ≥ 1 MetS component (exposure) were at increased risk of bleeding/non-bleeding periodontal diseases (outcome) compared to nonexposed individuals, propensity score matched for sex, age, race/ethnicity, and income (controls). The association between MetS components combinations and periodontal diseases was explored overall and across subgroups by sex and smoking. Periodontal health status prediction based on MetS components was assessed. RESULTS: In total, 2258 individuals (n. 1129/group) with nested clinical-demographic features were analyzed. Exposure was associated with gingival bleeding (+ 18% risk for every unitary increase in MetS components, and triple risk when all five were combined), but not with stable periodontitis; the association was specific for women, but not for men, irrespective of smoking. The only MetS feature with significant association in men was high BP with periodontitis. CRP levels significantly increased from health to disease only among exposed women. MetS components did not substantially improve the prediction of bleeding/non-bleeding periodontal disease. CONCLUSION: The observed women-specific association of gingival bleeding with single and combined MetS components advances gender and precision periodontology. Further research is needed to validate and expand these findings.

Histological and Histomorphometric Evaluation of New Bone Formation after Maxillary Sinus Augmentation with Two Different Osteoconductive Materials: A Randomized, Parallel, Double-Blind Clinical Trial.

This study aimed to investigate the histological features of deproteinized equine bone mineral (DEBM) and anorganic bovine bone (ABB) after human sinus augmentation with the lateral approach. Twenty-three sinus augmentations were performed in 16 patients (male: 10/female: 6) using DEBM or ABB in a randomized fashion. Healing took place over the next 6 months. Bone core biopsies (N = 23) were obtained for each subject prior to placing the dental implants. The biopsies were processed for both histological descriptions and histomorphometric analysis. Statistical analyses were applied as appropriate, defining statistical significance as p < 0.05. Core bone biopsies revealed no differences in terms of newly formed bone between groups, or differences in terms of tissue inflammation. Both DEBM and ABB appear to be suitable biomaterials for bone augmentation in sinus lift surgery in the short term. However, dedicated studies are required to confirm these results and their stability in the long term.

Periodontitis and Hypertension: Is the Association Causal?

High blood pressure (BP) and periodontitis are two highly prevalent conditions worldwide with a significant impact on cardiovascular disease (CVD) complications. Poor periodontal health is associated with increased prevalence of hypertension and may have an influence on BP control. Risk factors such as older age, male gender, non-Caucasian ethnicity, smoking, overweight/obesity, diabetes, low socioeconomic status, and poor education have been considered the common denominators underpinning this relationship. However, recent evidence indicates that the association between periodontitis and hypertension is independent of common risk factors and may in fact be causal in nature. Low-grade systemic inflammation and redox imbalance, in particular, represent the major underlying mechanisms in this relationship. Neutrophil dysfunction, imbalance in T cell subtypes, oral-gut dysbiosis, hyperexpression of proinflammatory genes, and increased sympathetic outflow are some of the pathogenetic events involved. In addition, novel findings indicate that common genetic bases might shape the immune profile towards this clinical phenotype, offering a rationale for potential therapeutic and prevention strategies of public health interest. This review summarizes recent advances, knowledge gaps and possible future directions in the field.

Neutral zone recording in computer-guided implant prosthesis: A new digital neuromuscular approach.

Background: Neutral zone (NZ) is a specific area in the oral cavity where muscular opposite forces are null. NZ represents the ideal zone for prosthesis placement. In this study, we compared digital implant planning using conventional technique and using NZ registration through piezography. Methods: Sixty-tree implants were digitally planned. Angular deviation differences between traditional planned and NZ-planned implants were calculated. In addition, interferences with soft tissues (i.e., tongue and cheeks) were evaluated. Results: We observed a significant difference between traditional technique and piezographic approach in terms of implants angulation (p = .003), independent of site. A 4.7% of the planned abutments with traditional technique were placed outside the NZ, causing conflict with soft tissues in the digital model. Conclusions: Compared with traditional technique, piezography allows a significantly different exploitation of the nonconflict area, which potentially translates into better management of soft tissues and improved functionality of the implants.

Occurrence of spontaneous periodontal disease in the SAMP1/YitFc murine model of Crohn disease.

BACKGROUND: Oral involvement is often associated with inflammatory bowel disease (IBD). Recent evidence suggests a high incidence of periodontal disease in patients with Crohn disease (CD). To the best of the authors' knowledge, no animal model of IBD that displays associated periodontal disease was reported previously. The aim of this study is to investigate the occurrence and progression of periodontal disease in SAMP1/YitFc (SAMP) mice that spontaneously develop a CD-like ileitis. In addition, the temporal correlation between the onset and progression of periodontal disease and the onset of ileitis in SAMP mice was studied. METHODS: At different time points, SAMP and parental AKR/J (AKR) control mice were sacrificed, and mandibles were prepared for stereomicroscopy and histology. Terminal ilea were collected for histologic assessment of inflammation score. Periodontal status, i.e., alveolar bone loss (ABL) and alveolar bone crest, was examined by stereomicroscopy and histomorphometry, respectively. RESULTS: ABL increased in both strains with age. SAMP mice showed greater ABL compared with AKR mice by 12 weeks of age, with maximal differences observed at 27 weeks of age. AKR control mice did not show the same severity of periodontal disease. Interestingly, a strong positive correlation was found between ileitis severity and ABL in SAMP mice, independent of age. CONCLUSIONS: The present results demonstrate the occurrence of periodontal disease in a mouse model of progressive CD-like ileitis. In addition, the severity of periodontitis strongly correlated with the severity of ileitis, independent of age, suggesting that common pathogenic mechanisms, such as abnormal immune response and dysbiosis, may be shared between these two phenotypes.