Peri-implantitis disease has increased significantly over the last years, resulting in increased failure of implants. Many factors may play a role in implant complications and failure, including ones related to the oral microbiota. This literature review aims to summarize the current knowledge of microbiome of implants in health and disease, focusing not only on the presence/absence of specific microbiota or on their relative abundance, but also on their phenotypic expression and their complex relationships with the host. The authors examined the MEDLINE database and identified key topics about peri-implant oral microbiome in health and disease. The peri-implant microbiome differs from that of the tooth, both in health and disease, as they are structurally and chemically different. The adhesion and formation of the peri-implant biofilm can be affected by the surface energy, topography, wettability, and electrochemical charges of the implant surface. In addition, the morphogenesis of the tissues surrounding the dental implant also differs from the tooth, making the dental implant more susceptible to bacterial infection. This interplay between the microbiome and the host immune system in peri-implant infections still needs to be elucidated.

Kajimoto ND, et al. J Periodontal Implant Sci. 2021 Dec;51(6):374-385. https://doi.org/10.5051/jpis.2100700035

Periodontitis is a chronic inflammatory disease driven by microbial dysbiosis and an exacerbated host immune response, leading to progressive periodontal tissue breakdown and contributing to systemic inflammation. Although scaling and root planing remains the standard treatment, its capacity to fully restore immune balance and host–microbiota homeostasis is limited. In this context, probiotics have emerged as promising adjunctive strategies capable of modulating immunological and metabolic pathways involved in disease progression. This narrative review aimed to evaluate current evidence regarding the use of probiotics in periodontal therapy. The review followed the Scale for the Assessment of Narrative Review Articles (SANRA) guidelines. A literature search was conducted in MEDLINE via PubMed for manuscripts indexed up to January 2026 using MeSH-based terms related to periodontitis and probiotics. Evidence from preclinical and clinical studies suggests that probiotics may reduce alveolar bone loss and periodontal inflammation by downregulating proinflammatory mediators, enhancing anti-inflammatory cytokine production, strengthening epithelial barrier function, and modulating innate and adaptive immune responses. Additionally, probiotics may exert systemic effects through interactions with the gut microbiota, potentially improving metabolic regulation and reducing systemic inflammation. Overall, current evidence supports probiotics as biologically plausible adjuncts to periodontal therapy.

Periodontitis is a chronic inflammatory disease driven by microbial dysbiosis and an exacerbated host immune response. This leads to progressive breakdown of periodontal tissues. Although scaling and root planing remains the standard treatment, its capacity to fully restore immune balance and host–microbiota homeostasis is limited. Probiotics have emerged as promising adjunctive strategies to modulate pathways involved in periodontal disease progression. This review aimed to evaluate current clinical evidence on the use of probiotics as adjuncts in periodontal therapy. The review followed the Scale for the Assessment of Narrative Review Articles criteria, applied exclusively as a reporting-quality framework. A literature search was conducted in MEDLINE via PubMed for manuscripts indexed through January/2026, using MeSH terms related to periodontitis and probiotics. Probiotics demonstrate potential as adjunctive agents in periodontal therapy, as evidenced by improvements in clinical parameters (probing depth, clinical attachment level, and/or bleeding on probing) reported in clinical studies. However, the findings remain heterogeneous across trials. Variability in probiotic strains, CFU concentrations, administration routes, and treatment durations highlights the need for standardized clinical protocols to improve comparability and reproducibility and better establish their clinical efficacy. Stronger, long-term evidence is required to standardize therapeutic protocols.