THE EFFECTIVENESS OF PERIODONTAL TREATMENT IN REDUCING TOOTH LOSS: A COHORT STUDY

ABSTRACT OBJECTIVES To evaluate the effectiveness of comprehensive periodontal treatment in reducing tooth loss and to identify predictors of tooth survival among patients with chronic periodontitis. METHODOLOGY A prospective cohort study was conducted from January 2024 to April 2025 at a tertiary care dental hospital. A total of 240 adults with moderate to severe chronic periodontitis were enrolled using systematic sampling; 222 completed the 12-month follow-up. All participants received standardized non-surgical periodontal therapy, with surgical intervention where indicated, followed by supportive periodontal care. Clinical periodontal parameters were recorded at baseline and follow-up using structured examination forms. Tooth loss events were documented prospectively. Statistical analysis included paired t-tests, Kaplan-Meier survival analysis with log-rank testing, and multivariate Cox proportional hazards regression. RESULTS Significant improvements were observed in probing depth (mean reduction: 2.1 mm), clinical attachment level (1.1 mm), and bleeding on probing (33.7%) at 12 months (p < 0.001). The mean annual tooth loss was 0.38 ± 0.61 teeth per patient, representing a 73% reduction compared with the pre-treatment period. Kaplan-Meier analysis demonstrated significantly higher tooth survival among compliant patients who received supportive periodontal therapy (96.2%) than among irregular attenders (87.4%; log-rank p < 0.001). Multivariate Cox regression identified regular maintenance as a strong protective factor against tooth loss (HR = 0.41; 95% CI: 0.27-0.62), while smoking (HR = 1.92), diabetes mellitus (HR = 1.61), and baseline clinical attachment loss ≥6 mm (HR = 2.08) significantly increased tooth loss risk. CONCLUSION Comprehensive periodontal treatment substantially reduces tooth loss, particularly when reinforced through regular supportive periodontal therapy. Maintenance compliance, smoking status, systemic health, and baseline disease severity are key determinants of long-term tooth survival. These findings support integrating structured maintenance programs into periodontal care to preserve natural dentition