Responses of four tooth and site groupings to periodontal therapy.

The responses of four tooth/site groupings to periodontal therapy were evaluated. Eighty-two patients with periodontitis were treated in a split mouth design with coronal scaling, root planing, modified Widman surgery, and flap with osseous resectional surgery. Patients were evaluated prior to therapy, 4 weeks post-Phase I therapy, 10 weeks post-Phase II therapy, and at yearly intervals during 2 years of maintenance therapy. The tooth/site groupings evaluated were: 1) interproximal sites of single rooted teeth (T1), 2) facial and lingual sites of single rooted teeth (T2), 3) nonfurcation sites of molar teeth (T3), and 4) furcation sites of molar teeth (T4). Following 2 years of maintenance, no clinically significant differences in probing depth reduction or probing attachment loss were present between the four tooth/site groupings in 1 mm to 4 mm sites. T2 had the greatest decrease of probing depth in 5 mm to 6 mm sites followed by T1, T3 and T4. T1 and T2 showed a greater gain of probing attachment followed by T3 and T4. T1 and T2 had the greatest decrease of probing followed by T3 which was greater than T4 in greater than or equal to 7 mm sites. T4 had significantly less probing attachment gain than the other groups. There was a trend for T1 and T2 to have less gingival bleeding post-therapy and for T2 to have less plaque accumulation than the other groups at both pre- and post-therapy examinations.