Radiographic evaluation of bone regeneration following periodontal surgery with or without expanded polytetrafluoroethylene barriers
The clinical purpose of this study was to compare the results of treatment using GTR with conventional periodontal surgery in the therapy of interproximal intrabony defects. This study also evaluated the validity of standardized vertical bitewing radiographs in assessing the results of therapy. The radiographic distances measured using a loupe were compared to a computer-assisted method.
Sixteen patients having 23 interproximal intrabony defects requiring periodontal surgery were selected for the study. Ten defects made up the control and were treated by conventional periodontal surgery in which a mucoperiosteal flap was elevated to the alveolar crest. Thirteen defects were treated with GTR and constituted the experimental group. Membranes were retrieved four to six weeks after implantation. Both groups were similar in gingival index, clinical attachment levels, and plaque index. Initial differences in probing depth were statistically significant. Presurgically and at three and six months postsurgically, standardized bitewing radiographs were taken. The distances from the CEJ to alveolar crest and CEJ to the most apical extension of the bony defect were measured using both loupe and a computer-assisted system.
The results using the loupe showed that bone fill was measured at 0.97 mm in the control group at the three- and six-month points. The test group showed 0.93 mm and 1.68 mm bone fill during the same period. The computer-assisted system showed greater bone fill (1.82 mm for control and 1.79 mm for test) after the six-month period when compared to the loupe measurement. The average gain in clinical attachment was assessed at 2.33 mm in the control group and 3.17 mm in the test group. Compared to the gold standard of surgical measurements, the computer- assisted analysis of radiographs underestimated bone loss significantly less than evaluation with a loupe.
Overall, the GTR technique resulted in higher attachment gain and bone fill, but a statistically significant difference was not calculated. [D.S.S.]
Eickholz, P., D. Benn, and H. Staehle, J Periodont, 67:379, 1996