A comparative 4-month trial was performed after initial preparation. The procedures used were curettage, replaced flap and apically repositioned flap procedures with osseous recontouring respectively in a split-mouth technique in 17 male and 23 female patients, 22 to 65 years old. Changes were assessed with plaque and gingival indices, and measurements of pocket depths, attachment levels and tissue contours. All procedures reduced pocket depths. Apically repositioned flaps were the most successful, reducing overall mean pockets from 3.5 to 1.9 mm. Changes in attachment levels post-operatively showed only a small degree of variation among the three surgical procedures, and would not affect the choice of the apically repositioned flap as the most effective method for pocket reduction. A marked improvement in tissue contour was obtained in those areas treated by apically repositioned flap procedures and osseous recontouring. Despite failure to improve tissue contour, replaced flap procedures showed an equal degree of success in maintaining plaque control when compared to apically repositioned flaps, as evidenced by static plaque indices. Replaced flap procedures were also the only group to show improved gingival health over the 4-month post-operative period with lower gingival indexes. It would seem that good healing, followed by a high standard of oral hygiene, may overcome the presence of gingival and marginal osseous deformities.