[Effect of supportive periodontal therapy in maintaining the long-term effect of the initial therapy].

Objective: To evaluate the influence of supportive periodontal therapy to the long-term effect after initial therapy.
Methods: The investigation was conducted as a retrospective longitudinal study over a period of at least 2 years, a total of 39 patients recruited in the study and divided into non-maintenance group (n=22) and maintenance group (n=17). Non-maintenance group were monitored for an average of 5.09 years, maintenance group were monitored for an average of 7.53 years. The changes of following variables were recorded and analyzed: the number of loss tooth, probing depth (PD), bleeding index, alveolar bone level in full mouth radiographs.
Results: It was observed that (1) patients without maintenance lost more teeth compared to the maintenance groups, showed no changes of PD percentage but significant decrease in bone level; (2) patients received maintenance showed significant decreases in PD, bone level keep stable during the observation compared to the non-maintenance group.
Conclusion: Supportive periodontal therapy not only decreased the probing depth, but also prevented alveolar bone loss. Supportive periodontal therapy after initial therapy plays a crucial role in keeping periodontal health for long-term.