SUMMARY: Recent advances in therapeutic probiotics have shown promising results across various health conditions, reflecting a growing understanding of the human microbiome’s role in health and disease. However, comprehensive reviews integrating the diverse therapeutic effects of probiotics in human subjects have been limited. By analyzing randomized controlled trials (RCTs) and meta-analyses, this review provides a comprehensive overview of key developments in probiotic interventions targeting gut, liver, skin, vaginal, mental, and oral health. Emerging evidence supports the efficacy of specific probiotic strains and combinations in treating a wide range of disorders, from gastrointestinal (GI) and liver diseases to dermatological conditions, bacterial vaginosis, mental disorders, and oral diseases. We discuss the expanding understanding of microbiome-organ connections underlying probiotic mechanisms of action. While many clinical trials demonstrate significant benefits, we acknowledge areas requiring further large-scale studies to establish definitive efficacy and optimal treatment protocols. The review addresses challenges in standardizing probiotic research methodologies and emphasizes the importance of considering individual variations in microbiome composition and host genetics. Additionally, we explore emerging concepts such as the oral-gut-brain axis and future directions, including high-resolution microbiome profiling, host-microbe interaction studies, organoid models, and artificial intelligence applications in probiotic research. Overall, this review offers a comprehensive update on the current state of therapeutic probiotics across multiple domains of human health, providing insights into future directions and the potential for probiotics to revolutionize preventive and therapeutic medicine.

Hwang J, et al. J Periodontal Implant Sci. 2024 Jul;54:e17. https://doi.org/10.5051/jpis.2304520226

Cho YD, et al. J Periodontal Implant Sci. 2023 Feb;53:e5. https://doi.org/10.5051/jpis.2203680184

Dental clinicians and researchers have recently recommended oral microbial examinations to more accurately diagnose and treat oral diseases, including periodontitis and dental caries. Theoretical and experimental evidence suggests that oral microbiota may also be associated with non-oral diseases, such as gastrointestinal and extra-gastrointestinal diseases. This review highlights studies demonstrating microbial alterations in the oral cavity associated with malignant tumors including gastric, colorectal, esophageal, and lung cancers, implying that these alterations may serve as early indicators for non-invasive diagnosis and risk assessment of cancer development. Furthermore, we addressed the implications of oral microbial co-occurrence with malignant tumors, such as Streptococcus anginosus, Fusobacterium nucleatum, and Veillonella parvula, which are recognized as tumor-enriched oral pathogens involved in the development and progression of cancers in the stomach, colon, and lungs, respectively. Notably, we explored the immune and inflammatory mechanisms underlying reciprocal interactions between oral microbiota and tumors, underscoring that targeting these mechanistic pathways can contribute to preventing cancer development.

Objectives: This case study aimed to evaluate changes in periodontal pathogens and systemic disease indicators following the adjunctive use of probiotics for periodontal treatment. Methods: Two adults, a 64-year-old male and 71-year-old female, were selected with ethical approval and underwent comprehensive oral and systemic health assessments before and after probiotic intake with periodontal debridement. Results: There was a significant reduction in the periodontal pathogens, particularly Porphyromonas gingivalis and Treponema forsythia, and no adverse systemic indicators were observed. Moreover, a trend toward improved lipid profiles was noted, suggesting a potential positive impact on systemic health. Conclusions: This study shows the potential role of probiotics in enhancing oral health and preventing systemic diseases, thus highlighting the need for further research and clinical trials.

Shin HR, et al. J Periodontal Implant Sci. 2025 Feb;55:e2. https://doi.org/10.5051/jpis.2401920096