The increasing importance of the oral microbiome in periodontal health and disease

Microbial functional pathways based on metatranscriptomic profiling enable effective saliva-based health assessments for precision wellness

It is increasingly recognized that an important step towards improving overall health is to accurately measure biomarkers of health from the molecular activities prevalent in the oral cavity. We present a general methodology for computationally quantifying the activity of microbial functional pathways using metatranscriptomic data. We describe their implementation as a collection of eight oral pathway scores using a large salivary sample dataset (n = 9350), and we evaluate score associations with oropharyngeal disease phenotypes within an unseen independent cohort (n = 14,129). Through this validation, we show that the relevant oral pathway scores are significantly worse in individuals with periodontal disease, acid reflux, and nicotine addiction, compared with controls. Given these associations, we make the case to use these oral pathway scores to provide molecular health insights from simple, non-invasive saliva samples, and as molecular endpoints for actionable interventions to address the associated conditions.

Association of endogenous sex hormone levels with tooth loss due to periodontitis in men and post-menopausal women: The multi-ethnic study of atherosclerosis

AIM

To investigate the association between endogenous sex hormone levels and history of tooth loss related to periodontitis in healthy middle-aged to older men and post-menopausal women.

METHODS

This cross-sectional study included 5649 participants aged 45-84 (mean age, 63 ± 10 years) from the Multi-Ethnic Study of Atherosclerosis cohort who had sex hormone levels measured and answered a questionnaire regarding perceived periodontal status at exam 1. Multivariable logistic regression was used to examine the association of sex hormones (exposure) with history of tooth loss (outcome), stratified by sex.

RESULTS

Among post-menopausal women, higher free testosterone (per 1SD) was associated with a greater prevalence of tooth loss [OR 1.49 (95% CI, 1.08-2.05)], whereas higher sex hormone binding globulin (SHBG) was associated with a lower prevalence of tooth loss [OR 0.74 (0.58-0.94)], after adjustment for cardiometabolic risk factors and reproductive factors. In men, higher free testosterone and lower SHBG were associated with a lower prevalent probability of tooth loss in unadjusted analysis, but these associations lost significance after covariate adjustment.

CONCLUSION

A higher androgenic sex hormone profile in post-menopausal women (i.e., increased free testosterone, lower SHBG) was associated with an increased prevalence of tooth loss, after adjusting cardiometabolic risk factors. No such association was found in men. These findings suggest that sex hormones may influence or serve as a marker for periodontal health.

The Bloody Crossroads: Interactions between Periodontitis and Hematologic Diseases

Periodontitis is a common oral condition that can have a significant impact on the overall health of the body. In recent years, attention has been paid to potential relationships between periodontitis and various hematological disorders. This publication aims to present information available in the literature on this relationship, focusing on examples of red blood cell disorders (such as aplastic anemia and sickle cell anemia) and white blood cell disorders (such as cyclic neutropenia, maladaptive trained immunity, clonal hematopoiesis, leukemia, and multiple myeloma). Understanding these associations can help physicians and dentists better diagnose, monitor, and treat patients associated with both groups of conditions, highlighting the need for interdisciplinary care for patients with oral disorders and hematologic diseases.

Microbiota Transplantation as an Adjunct to Standard Periodontal Treatment in Periodontal Disease: A Systematic Review

Periodontitis is a disease linked to severe dysbiosis of the subgingival microbiome. The treatment of periodontitis aims to change the dysbiosis environment to a symbiosis environment. We hypothesized that oral microbiota transplantation can lead to a significant improvement in periodontitis. Therefore, the aim of this study was to determine the effectiveness of microbiota transplantation after standard periodontal treatment in periodontitis patients. The search strategy was carried out by using the Boolean term "AND" to combine the keywords, which were "periodontitis AND microbiota transplantation". Due to the limited resources of the study, we included both in vitro and in vivo investigations in this systematic review. The QUIN risk of bias tool was employed to assess the risk of bias in in vitro studies, while SYRCLE's risk of bias assessment was used for in vivo studies. Oral microbiota transplants (OMTs) have shown potential in treating periodontitis. OMTs significantly reduced periodontitis-associated pathogenic microbial species (P. endodontalis, Prevotella intermedia, T. vincentii, Porphyromonas sp.) and increased beneficial bacteria (P. melaninogenica, Fusobacterium nucleatum, P. catoniae, Capnocytophaga ochracea, C. sputigena, C. gingivalis, Haemophilus parainfluenzae, and Neisseria elongata) upon in vitro testing. Furthermore, in the in vivo tests, single adjunctive OMT also had an effect on the oral microbiota composition compared to the full-mouth mechanical and antimicrobial debridement. OMTs may be cheaper and more effective at addressing high-risk individuals. At present, it is not possible to provide OMT clinical advice due to the lack of available information. This treatment needs to be subjected to more safety and efficacy testing before being included human clinical trials.

The Complicated Relationship of Short-Chain Fatty Acids and Oral Microbiome: A Narrative Review

The human oral microbiome has emerged as a focal point of research due to its profound implications for human health. The involvement of short-chain fatty acids in oral microbiome composition, oral health, and chronic inflammation is gaining increasing attention. In this narrative review, the results of early in vitro, in vivo, and pilot clinical studies and research projects are presented in order to define the boundaries of this new complicated issue. According to the results, the current research data are disputable and ambiguous. When investigating the role of SCFAs in human health and disease, it is crucial to distinguish between their local GI effects and the systemic influences. Locally, SCFAs are a part of normal oral microbiota metabolism, but the increased formation of SCFAs usually attribute to dysbiosis; excess SCFAs participate in the development of local oral diseases and in oral biota gut colonization and dysbiosis. On the other hand, a number of studies have established the positive impact of SCFAs on human health as a whole, including the reduction of chronic systemic inflammation, improvement of metabolic processes, and decrease of some types of cancer incidence. Thus, a complex and sophisticated approach with consideration of origin and localization for SCFA function assessment is demanded. Therefore, more research, especially clinical research, is needed to investigate the complicated relationship of SCFAs with health and disease and their potential role in prevention and treatment.