Comparative Analysis of Oral Bacterial Profiles in Parkinson’s Disease According to Periodontal Status: A Clinical Case Series

<b>Introduction</b>: Parkinson's disease can influence oral health by impairing motor function and altering salivary composition, potentially affecting the oral microbiome. <b>Materials and Methods</b>: The objectives of this study are fourfold: (a) to compare the prevalence of bacterial species associated with periodontal disease in patients with and without Parkinson's disease (PD), (b) to assess whether the coexistence of periodontal disease in PD patients contributes to an imbalance in the oral microbiome, (c) to evaluate the correlation between periodontal clinical indices (plaque index, tartar index, bleeding index, and probing depth) and the concentrations of specific periodontopathogenic bacterial species, and (d) to explore the potential implications of these evidences for clinical management and preventive strategies in Parkinson's patients. The main objective of this study is to compare periodontal clinical indices (plaque index, tartar index, bleeding index, and probing depth) and the bacterial profile of patients with periodontal and Parknson's disease. Two groups were included: 15 patients with periodontal disease (control group) and 16 patients with both periodontal and Parkinson's disease (study group). Microbial samples were collected from the periodontal pockets at baseline and analyzed using the Polymerase Chain Reaction (PCR) Perio-Ident 12 kit to detect major periodontal pathogens. <b>Results</b>: Periodontal indices showed no statistically significant differences between groups, although the study group presented lower mean tartar index (49.31% vs. 67.4%, <i>p</i> = 0.069), bleeding on probing (44.31% vs. 56.67%, <i>p</i> = 0.137), and plaque index (66% vs. 68.93%, <i>p</i> = 0.754). Median bacterial loads were generally higher in control group, with <i>Tannerella forsythia</i>, but without statistically significant difference (<i>p</i> = 0.072). Significant correlations between plaque index and multiple pathogens occurred only in control gorup, suggesting disrupted plaque-pathogen dynamics (<i>p</i> < 0.05). <b>Conclusions</b>: The results highlight the potential value of integrating clinical and microbiological assessment when managing periodontal disease in patients with Parkinson's disease.