Healing patterns in recession defects treated with ePTFE membranes and with free connective tissue grafts. A histologic and histometric study in the beagle dog

This study focussed on the biologic success of 2 different procedures for root coverage. In the maxillary canines of 7 beagle dogs, buccal recessions were created and treated on one side with an ePTFE membrane (GTR-group) and on the contralateral side with a free connective tissue graft from the palate (CT-group). 2 areas served as negative controls. After 4 months of healing, histologic sections were processed and histologically analyzed. The evaluated parameters were coverage height, bone, cementum and connective tissue attachment regeneration, length of the epithelium, resorption, and ankylosis. Histologically, both GTR-group and CT-group produced more new bone, new cementum and new connective tissue attachment than the two control teeth. When histologically evaluated, the amount of new bone was more pronounced in the GTR-group than in the CT-group, however, no statistical differences in any of the evaluated parameters could be detected between the 2 procedures tested. Frequency and distribution of resorption and ankylosis were similar in the GTR-group and in the CT-group. Within the limits of this study, no differences in terms of the biologic rehabilitation between those recessions treated with ePTFE membranes and those treated with a free connective tissue graft could be found.