Histologic and Histomorphometric Assessment of Xenograft Bone Substitute versus Synthetic Nonceramic Hydroxyapatite...

This study sought to histologically and histomorphometrically assess and compare application of xenograft bone substitute and synthetic nonceramic hydroxyapatite for tooth-socket preservation in dogs. This split-mouth clinical trial was conducted in five hybrid dogs, using four tooth sockets in each dog, with a total of 20 sockets for evaluation. Group 1 received xenografts, and group 2 received synthetic nonceramic hydroxyapatite in the sockets. In group 3 (positive controls), sockets remained empty. All sockets were covered with collagen resorbable membrane, and the flap was stitched using nonresorbable sutures. In group 4 (negative control), sockets were without membrane, left empty, and sutured. After 12 wk, 8-mm-high bone core biopsies were harvested from inside the sockets, using a trephine bur with an internal diameter of 2 mm. We assessed the tissue in terms of percentage of newly formed viable bone, percentage of remaining particles, degree of inflammation, and type of connective tissue. Data were statistically analyzed. The percentage of newly formed viable bone was 34.98% in group 1 and 41.30% in group 2, and this difference was not statistically significant (p = 0.710). The percentage of remaining particles was 15.95% in group 1 and 14.14% in group 2; this difference was also not statistically significant (p = 0.902). Both synthetic nonceramic hydroxyapatite and xenograft bone substitute showed similar efficacy, histologically and histomorphometrically, when used with resorbable collagen membrane for tooth-socket preservation in dogs.