Comparison of Guided Tissue Regeneration Procedure to Conventional Flap Surgery in Treating Intrabony and Class II Furcation Defects, and Analysis of Factors Affecting the Prognosis Following GTR.

Abstract

The purposes of this study were (1) by means of such a randomized controlled study to compare the effects of the guided tissue regeneration (GTR) procedure with conventional flap surgery (CFS) as a control treatment on the healing of deep intrabony and class II furcation defects, and (2) to determine factors affecting the clinical outcome of the GTR procedure using a multivariate approach.Sixty deep intrabony defects and 20 class II furcation defects were treated in 80 adult periodontitis patients aged from 35 to 60 years. After completion of initial therapy, those defects were assigned to either by a GTR or CFS procedure with matching age, gender, teeth and defect morphology. A postsurgery protocol emphasizing wound stability and infection control was used. Treatment effects were evaluated at 6 months and 1 year postsurgery.Both GTR and CFS for intrabony and furcation defects resulted in a clinically and statistically significant improvement in probing pocket depth (PPD), vertical and horizontal clinical attachm ent level (CAL-V, CAL-H), marginal tissue recession MTR) and radiographic bone loss (BL), at 6 months and 1 year postsurgery compared to baseline measurements. Moreover, there was a more favorable improvement in CAL-V, MTR and BL of the GTR group than in the CFS group at 6 months and 1 year postsurgery for intrabony defects. In addition, the GTR group showed greater improvement in CAL-H than CFS group at both 6 months and 1 year postsurgery for furcation defects. When multivariate analysis assessing the significance of the tested factors in determining the healing outcomes following GTR procedure was performed for intrabony defects, PPD at baseline was of predictive value for vertical clinical attachment gain (CAL-V gain) at 6 months postsurgery, and CAL-V gain and MTR at 6 months postsurgery were of predictive values for CAL-V gain at 1 year postsurgery. BL at baseline and at 6 months postsurgery was also of predictive value for bone fill at 6 months and 1 year postsurgery, respectively. In furcation defects, CAL-H and MTR at baseline were predictive values for horizontal clinical attachment gain (CAL-H gain) at 6 months postsurgery, and CAL-H gain at 6 months postsurgery was of predictive value for CAL-H gain at 1 year postsurgery.These findings suggest that initial PPD and BL in intrabony defects, and initial CAL-H in class II furcation defects might be useful in assessing the regenerative potential of a given site and the degree could be predictive values for a follow-up in tissue of improvement as early as 6 months postsurgery regeneration.