Aim: The purpose of this retrospective analysis was to examine what effect, if any, the time elapsed between an individual's last episode of scaling and root planing and subsequent treatment with a sustained-release doxycycline hyclate gel (DH) alone or scaling and root planing alone (SRP) would have upon adult periodontitis.
Methods: A total of 207 subjects were included in the DH group and 210 patients in the SRP group. Periodontitis was defined as those sites which presented with pocket depths > or =5 mm and exhibited bleeding upon probing. In both DH and SRP groups, 3 sub-groups of subjects were identified according to their last episode of scaling and root planing prior to the study baseline: within 2 to 6 months, >6 but < or =12 months, and one or more times in their life but not within the last 12 months. Each study site was treated twice over a 9-month study period, once at baseline and again at 4 months. Data from the study sites at 4, 6, and 9 months were then evaluated for changes in probing depth, clinical attachment level, and bleeding upon probing.
Results: At the 9-month evaluation, all sub-groups in the DH and SRP treatment arms presented with improvement in the measured clinical parameters, as compared to baseline. No significant differences were observed in the measured periodontal indices among the study sites between the three sub-groups for either treatment.
Conclusions: It is concluded that the time interval since the last episode of scaling and root planing had no observable effect on the results achieved when treating periodontitis sites with locally delivered doxycycline hyclate alone or scaling and root planing alone. The treatment of periodontitis sites with locally delivered doxycycline hyclate resulted in clinical improvement comparable to scaling and root planing irrespective of the patient's prophylaxis frequency.