THE INFLUENCE OF THE DESIGN OF 2 DIFFERENT BIORESORBABLE BARRIERS ON THE RESULTS OF GUIDED TISSUE REGENERATION THERAPY - AN INTRAINDIVIDUALCOMPARATIVE-STUDY IN THE MONKEY

THE AIM OF THE PRESENT STUDY was to compare two bioresorbable barriers to evaluate whether differences in design influence the result of gui ded tissue regeneration (GTR) therapy, Twenty-four (24) plaque exposed , recession type defects in 4 monkeys were treated. Contralateral defe cts were randomized for test or control treatment. During a healing pe riod of 6 weeks, gingival recession resulting in device exposure occur red at 3 test and 10 control sites. One control barrier was exfoliated . Histologically, 9 of the 12 test barriers were completely integrated with the surrounding tissues. At 3 test sites, epithelium had migrate d apically outside the barrier to a level not exceeding one-third of t he height of the device. Seven of the 11 control barriers were enclose d by dentogingival epithelium. The adjacent connective tissue exhibite d local inflammatory cell infiltrates (ICT). At the remaining 4 contro l sites, the epithelial downgrowth as well as the adjacent ICT areas w ere limited to the coronal 1/3 of the device. New attachment; i.e., ne w cementum with inserting collagen fibers, averaged 2.2 mm and 0.8 mm at the test and control sites respectively (P < 0.01). Based on the re sults of the present study, it was concluded that a bioresorbable GTR device, designed to prevent epithelial downgrowth along the barrier su rface, has a higher potential to promote new attachment formation than a device which does not have this property.