John Rong Hao Tay, Ethan Ng, Dawn Shu Fen Siow, Stella Jinran Zhan, Seyed Ehsan Saffari, R Pamela López, Philip M. Preshaw
AIM: To investigate whether the number of residual probing pocket depths (PPDs) ≥ 5 mm predicts periodontitis progression in non-smoking patients undergoing supportive periodontal care (SPC). MATERIALS AND METHODS: This retrospective study included 121 patients (3028 teeth), with Stage III/IV, Grade B/C periodontitis, who completed active periodontal therapy and were enrolled in SPC. Multivariable logistic regression with inverse probability censoring weighting assessed the association between the number of residual sites with PPD ≥ 5 mm at the start of SPC and disease progression at 1-year and 5-year intervals. Receiver operating characteristic (ROC) curve analysis was used to identify optimal thresholds for predicting progression. RESULTS: Each additional site with PPD ≥ 5 mm at the start of SPC was associated with higher odds of disease progression (≥ 2 mm PPD increase at any site) after 1 year (adjusted OR: 1.15; 95% CI: 1.05-1.29). For periodontal tooth loss, each additional PPD ≥ 5 mm site increased the odds by 11% over 5 years. ROC analysis suggested that ≥ 6 residual sites provided the best discrimination for predicting 1-year PD progression (AUC: 0.73). CONCLUSION: Six or more residual PPDs ≥ 5 mm at SPC were associated with short-term disease progression, although the performance was modest.