Histological Evaluation of Alveolar Ridge Preservation Using Different Bone Grafts: Clinical Study Analysis Part II.

OBJECTIVE: To compare histologically the percentage of bone formation 12-20 weeks post-ridge augmentation using two different techniques.

BACKGROUND: Tooth loss is associated with three-dimensional bone remodeling and ridge atrophy. Ridge preservation procedures can prevent alveolar bone volume loss. Different techniques and materials are used to preserve the alveolar ridge.

MATERIALS & METHODS: Computer-generated randomization software was used to assign two ridge preservation techniques for 11 extraction sites. In group I (type I bovine Achilles tendon collagen plugs with bioactive resorbable calcium apatite crystals (CPCAC) and ingroup II, cortico-cancellous bone chips (CCBC) mix, and an expanded polytetrafluoroethylene (ePTFE) barrier membrane were placed. The histomorphometric studies were performed using a computer-based image analysis system (IMAGE-J 1.4, National Institute of Health, Bethesda, MD, USA) to calculate the pixel area of bone tissue and the remaining bone graft material. The histomorphometric data were analyzed using a Student's t-test to compare the measurements between the two experimental groups. This parametric statistical test was employed to determine if there were any statistically significant differences in the quantitative histological parameters between the groups. Results: The sockets that received CPCAC showed a lower (31.89%) percentage of native bone surface area compared to the CCBC group (43.87%). However, the difference was not statistically significant (P< 0.05). In addition, group CPCAC showed evidence of foreign body reaction.

CONCLUSION: The CCBC graft covered with an ePTFE barrier may induce more bone formation with minimal inflammation in an extraction socket compared to a collagen plug with calcium apatite crystals. In addition, histological analysis of the CPCAC graft showed evidence of foreign body reaction, which indicates a negative clinical impact.