This study evaluated the effect of periodontal therapy on clinical and microbiological parameters in 23 subjects with severe generalized early onset periodontitis. Therapy consisted of oral hygiene instruction and root planing and scaling, followed 3 months later by open flap debridement. Subjects were monitored for both clinical measures and levels of Actinobacillus actinomycetemcomitans and Porphyromas gingivalis as identified by indirect immunofluoresence. Clinical and microbiological evaluations were done at the start of the study, 3 months after the completion of root planing and scaling and 3 months after open flap debridement. Mean probing depth was reduced by both root planing and scaling and open flap debridement and the level of reduction demonstrated by both phases of therapy was similar to reductions found in studies that utilized subjects with chronic adult periodontitis. In contrast, reductions in attachment level due to the two phases of therapy, demonstrated in previous studies of subjects with adult periodontitis were not found in the young adult subjects with severe periodontal disease utilized in this study. Levels of A. actinomycetemcomitans were not significantly affected by root planing and scaling, but were reduced by open flap debridement. P. gingivalis was virtually eliminated by root planing and scaling, demonstrating that the two bacterial types respond differently to periodontal therapy. These changes in microbiological parameters were similar to those found in studies of localized juvenile periodontitis subjects, where surgery or antibiotics have been shown to be necessary to reduce levels of A. actinomycetemcomitans.

The purpose of this study was to evaluate one year of maintenance therapy in young adults with severe periodontitis (SP) who had previously received periodontal therapy consisting of root planing and scaling followed by open flap debridement. Subjects were evaluated with clinical and microbiological measurements at 3, 6, 9, and 12 months following the completion of active therapy. Subjects were included in the study if they completed a minimum of two evaluation appointments. Monitoring of these subjects during the maintenance phase was analyzed by three methods. First, changes in mean attachment level and mean probing depth were calculated at 3-month intervals to determine if the subjects continued to lose or gain attachment and/or had periodontal pockets of increasing or decreasing depth. Second, the frequency of periodontal breakdown was determined and compared to breakdown rates of subjects in other patient populations. Third, future changes in attachment level were related to the presence or absence of two putative periodontal pathogens, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis in subgingival plaque. Mean attachment level remained constant in 13 subjects who completed one year of maintenance therapy. However, mean probing depth increased at a yearly rate of 0.19 mm and in periodontally-involved sites pocket depth increased at a yearly rate of 0.65 mm both of which were statistically significantly different from 0 (P < .05). The frequency of periodontal breakdown in this study was higher than reported in other similar studies of different periodontitis patient populations. The remainder of the data in the study was from 21 subjects who had completed at least two recall appointments.(ABSTRACT TRUNCATED AT 250 WORDS)