Guided tissue regeneration in the treatment of infrabony defects on maxillary premolars. A pilot study.

The present study evaluated clinically and radiographically the short-term results of the healing of infrabony defects at maxillary premolars treated according to guided tissue regeneration (GTR). 9 patients with bilateral presence of infrabony defects with or without furcation involvements at maxillary premolars were selected. At baseline assessments of plaque and gingival indices, bleeding, probing pocket depth and attachment level, and furcation measurements were recorded. Conventional radiographs were obtained in a way that assured a reproducible projection geometry. One premolar was randomly treated with GTR and the contralateral with open debridement. Clinical and radiographic examinations were performed again 6 months postoperatively. The bone tissue changes were assessed by means of conventional radiographs and subtraction images. Sites treated by both procedures demonstrated an improvement of gingival conditions and a reduction of pocket depths. A statistically significant attachment gain was obtained for the test (mean 1.2 mm), but not for the control sites (mean 0.6 mm). The differences, though, were not significant between the test and control sites. Limited improvement in furcation closure was recorded. The radiographic examination demonstrated loss of bone tissue in four sites treated with GTR. The findings suggest that the regeneration of the periodontal soft and bone tissues was not significantly enhanced with the GTR therapy.