Abstract
OBJECTIVE: To investigate the influence of osteoarthritis (OA), bronchial asthma (BA), and the concomitant presence of both conditions on the progression of periodontitis over a five-year follow-up in patients under periodontal maintenance care. METHODS: This case–control longitudinal cohort study analyzed 276 patients divided into four age- and gender-matched groups. Healthy (no OA, no BA), OA, BA, and BAOA (both conditions), with 69 patients in each group. Baseline periodontal parameters, tooth loss due to periodontitis, number of deep pockets (≥ 5 mm), and additional treatment needs were assessed and compared across groups over a mean follow-up duration of 6.5 ± 2.2 years. RESULTS: At baseline, the Healthy group exhibited significantly more periodontal pockets ≥ 5 mm (11.4 ± 13.1) compared to the OA (4.6 ± 11.0), BA (2.8 ± 5.1), and BAOA (3.9 ± 7.6) groups (p < 0.001). However, this difference was not significant after adjusting for confounders (p = 0.715). Tooth loss due to periodontitis during follow-up was also not significantly different among groups (p = 0.169). The need for invasive treatments was lower in OA and BAOA patients compared to Healthy patients, but this trend did not reach statistical significance (OR = 0.39, p = 0.063 for OA; OR = 0.44, p = 0.092 for BAOA). CONCLUSION: The presence of OA and/or BA does not appear to significantly influence the progression of periodontitis when controlling for confounding variables in a maintained patient population. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12903-025-07086-9.