Periodontitis stage and grade modifies the benefit of regular supportive periodontal care in terms of need for retreatment and mean cumulative cost.

AIM: This study aimed to characterize the periodontal breakdown during supportive periodontal care (SPC) and to quantify the corresponding cost-effectiveness of periodontal therapy. MATERIALS AND METHODS: Data were obtained from charts of patients who received active periodontal therapy (APT) with a minimum follow-up of >/=10 years. Analysis was done to identify factors associated with the incidence of additional sub-gingival instrumentation (SGI) and/or surgery (SUR) during SPC and mean cumulative cost of recurrence was calculated. All relevant data were collected. RESULTS: In all, 442 patients were included. Over the follow-up period, 62% of Stage I and II patients and 72% of Stage III and IV patients required further treatment following the APT; 56.5% of SGI patients and 78.6% of SUR patients received a second intervention. SUR patients received more SUR during the follow-up period (p = .035). Stage III and IV patients received more SUR during SPC than Stage I and II patients (p = .001). Grade C patients received more SUR during the follow-up period (p < .05). During the 5-year period preceding retreatment, the mean SPC visits were lower for patients who did not require retreatment (p < .001). Risk factors such as regularity of maintenance, smoking and diabetes were related to a higher chance of receiving SUR during the follow-up period (p < .05). The mean cumulative costs indicated less recurrence cost for compliers in Stage III and IV or Grade B and C but not for those in Stage I and II or Grade A. CONCLUSIONS: The risk of relapse in the maintenance population may be correlated with higher stage and grade, patient compliance, modifiable risk factors and the nature of the treatment provided during APT. The total cost of treatment of recurrences was lower for compliers in Stage III/IV and Grade B/C compared with erratic compliers with the same severity and risk.