Exploring the Relationship between Psychoneuroimmunology and Oral Diseases: A Comprehensive Review and Analysis

Evidence for the association between psychological stress and peri-implant health among middle-aged and elderly adults: A systemic review

BACKGROUND

Chronic psychological stress (CPS) is increasingly recognized for its detrimental effects on systemic and oral health, yet its impact on peri-implantitis remains underexplored.

AIM

To evaluate the evidence linking CPS to peri-implantitis.

METHODS

This systematic review was conducted according to the PRISMA guidelines. Publications searching PubMed, EMBASE, MEDLINE, Cochrane Library, and ClinicalTrials.gov for human studies published in English from 1983 to December 2024. Additionally, quality assessment of selected full-text articles were performed using the modified Newcastle–Ottawa Scale.

RESULTS

From an initial total of 3964 studies, 4 cross-sectional studies comprising 432 participants met the inclusion criteria and consistently demonstrated a positive association between CPS and peri-implantitis. However, the findings are compromised by small sample sizes, study design limitations, methodological heterogeneity, and inadequate adjustment for critical confounders such as smoking and prior periodontitis.

CONCLUSION

Cortisol levels in peri-implant sulcus fluid were linearly correlated with probing depth, with evidence suggesting this relationship may be independent of hyperglycemia. Depression emerged as the most significant CPS subtype associated with peri-implantitis. Additionally, CPS may amplify peri-implantitis inflammation by modulating cytokine expression effects. Long-term studies with larger, more diverse patient populations and careful control of confounding variables are needed to establish causality and understand the underlying mechanisms. Including psychological evaluations and stress management techniques in peri-implant care protocols could improve treatment outcomes and patient health.

Recurrent aphthous stomatitis (RAS) and its related factors among the Azar cohort population

INTRODUCTION

Recurrent aphthous stomatitis (RAS) is one of the most prevalent oral inflammatory ulcerative lesions, characterized by painful ulcers that develop on non-keratinized oral mucosa, significantly affecting the quality of life. This study aimed to evaluate the prevalence of RAS and its associated risk factors within the Azar cohort population.

METHODS

This cross-sectional study utilized data from the Azar cohort, which has been ongoing since 2014 in Shabestar City, East Azarbaijan, Iran, involving 15,006 adults aged 35 to 70 years. To assess the prevalence of RAS, participants were provided with a description of these lesions and asked whether they had ever experienced RAS in the oral cavity. Data collection was based on self-reports and examinations conducted by the physicians involved in the Azar cohort. Participants with RAS were classified into the RAS group, while the remaining participants were categorized into the non-RAS group. We assessed the association between RAS and various factors using binary logistic regression.

RESULTS

In the study population, there were 3,503 individuals in the RAS group and 11,503 individuals in the non-RAS group. The prevalence of RAS in the Azar cohort was 23.34%. Individuals over 50 years of age (p < 0.001), those with a poor (p < 0.001) or very poor (p = 0.02) socio-economic status, a low educational level (p = 0.01), smokers (p < 0.001) and individuals with a history of smoking who have since quit (p = 0.01) were significantly less affected by RAS. Conversely, individuals with genital aphthous lesions (p < 0.001), depression (p < 0.001), rheumatoid disease (p = 0.01), and food allergies (p < 0.001) were significantly more affected by RAS.

CONCLUSIONS

Factors such as being under 50 years of age, possessing a high socioeconomic status, having a higher level of education, experiencing genital aphthous disease, suffering from depression, having rheumatoid disease, and having food allergies may be associated with a higher prevalence of RAS.

The Bidirectional Relationship Between the Gut Microbiome and Mental Health: A Comprehensive Review

The gut microbiome plays a fundamental role in mental health, influencing mood, cognition, and emotional regulation through the gut-brain axis. This bidirectional communication system connects the gastrointestinal and CNS, facilitated by microbial metabolites, neurotransmitters, and immune interactions. Recent research highlights the association between gut dysbiosis and psychiatric disorders, including anxiety, depression, and stress-related conditions. Key findings indicate that altered microbial diversity, decreased short-chain fatty acid (SCFA) production, and increased neuroinflammation contribute to mental health disturbances. This paper explores the mechanism linking the gut microbiome to brain function, including microbial neurotransmitter synthesis, vagus nerve signaling, and hypothalamic-pituitary-adrenal (HPA) axis modulation. Additionally, it evaluates the potential of microbiome-targeted interventions, such as probiotics, prebiotics, dietary modifications, and fecal microbiota transplantation (FMT), in alleviating psychiatric symptoms. Microbiome sequencing and bioinformatics advances further support the development of personalized microbiome-based mental health interventions. Despite promising evidence, challenges such as inter-individual variability, methodological inconsistencies, and the need for longitudinal studies remain. Future research should focus on standardizing microbiome assessment techniques and optimizing therapeutic applications. Integrating precision psychiatry with microbiome-based diagnostics holds immense potential in transforming mental health treatment.