Search

Alveolar bone is the thickened ridge of jaw bone that supports teeth. It is subject to constant occlusal force and pathogens invasion, and is therefore under active bone remodeling and immunomodulation. Alveolar bone holds a distinct niche from long bone considering their different developmental origin and postnatal remodeling pattern. However, a systematic explanation of alveolar bone at single-cell level is still lacking. Here, we construct a single-cell atlas of mouse mandibular alveolar bone through single-cell RNA sequencing (scRNA-seq). A more active immune microenvironment is identified in alveolar bone, with a higher proportion of mature immune cells than in long bone. Among all immune cell populations, the monocyte/macrophage subpopulation most actively interacts with mesenchymal stem cells (MSCs) subpopulation. Alveolar bone monocytes/macrophages express a higher level of Oncostatin M (Osm) compared to long bone, which promotes osteogenic differentiation and inhibits adipogenic differentiation of MSCs. In summary, our study reveals a unique immune microenvironment of alveolar bone, which may provide a more precise immune-modulatory target for therapeutic treatment of oral diseases. [ABSTRACT FROM AUTHOR]

Sex is a biological variable that affects immune responses to bacterial and other types of infectious agents. Males and females are known to have differential oral bacterial disease burden in periodontal and endodontic disease. Understanding that there is a contribution from both sex and gender to these oral diseases, we discuss in this review recent sex-based findings that provide a pathobiological basis for differences observed between males and females. Sexual dimorphism of immune responses with respect to neutrophil trafficking and osteoclast differentiation and formation is presented as a plausible mechanism to explain the sexual differences. We also emphasize that sex, as a biological variable, should be considered in these types of oral immunologic studies. [ABSTRACT FROM AUTHOR]

Objective: To determine the patterns of tobacco usage among subjects with potentially malignant oral lesions or conditions through a comparative study design.Methods: The study was carried out in a span of 2 months on a sample of 120 subjects; 60 in case group (30 subjects with leukoplakia and oral submucous fibrosis [OSMF], respectively) and 60 subjects in control group (30 current smokers and current chewers, respectively), attending the tobacco cessation clinic at a private dental college hospital in Chennai city. Demographic data, details of tobacco usage, and Fagerstrom nicotine dependence scores (FNTD) were recorded in a prevalidated tobacco cessation intake form.Results: Cases with leukoplakia had a higher mean FNTD score when compared to the control group (P = 0.0001). The most common form of smokeless tobacco used by case (OSMF) subjects was found to be mawa (53%) significantly higher than the control group (P = 0.05). Mean FNTD scores of mawa users were higher than other tobacco users in both case and control group.Conclusion: The current study has hence put forth the role of mawa form of tobacco in causation of OSMF at a time when implementation of tougher anti-tobacco laws is the talk of the town. [ABSTRACT FROM AUTHOR]

Objective To evaluate the effect of chronic continuous hypoxia (CCH) in alveolar bone and its correlation with the inflammatory markers which play a key role in the development of periodontitis. Material and methods Wistar rats were exposed to CCH (600 mbar, 3 months). Macroscopic and histological analyses of alveolar bone were performed, together with measurement of oxidative stress and inflammatory parameters in gums and submandibular glands (SMG). Results HCC induced cortical alveolar bone loss, decreased interradicular bone volume and increased the periodontal ligament height compared to control rats (p < 0.05). CCH enhanced iNOS activity in gums (from 2735,04 ± 662,96 nmol/min/mg proteins to 4289,58 ± 915,63 p < 0.05) and in SMG (from 56,71 ± 12,05 nmol/min/mg proteins to 90,15 ± 21,78 p < 0.05). PGE 2 did not change in gums or in SMG by means of CCH, while TNFα decreased in gums (p < 0.05). Regarding oxidative stress, thiobarbituric acid reactive species concentration in CCH animals was higher both in gums as in SMG, and catalase activity was decreased in SMG. Conclusion Higher iNOS activity both in gums and SMG under CCH could be associated with the alveolar bone loss observed. The increase in oxidative stress occurring in SMG and gums, together with a lower antioxidant capacity might indicate a deleterious effect of HX in oral health. [ABSTRACT FROM AUTHOR]