Comparison of different bone substitutes in the repair of rat calvaria critical size defects: questioning the need for alveolar ridge presentation.

This study aimed to evaluate the effectiveness of biomaterials in bone healing of critical bone defects created by piezoelectric surgery in rats calvaria. Histomorphological analysis was performed to assess bone regeneration and tissue response. Fifty animals were randomized into 5 groups with one of the following treatments: Control group (CO, n=10), spontaneous blood clot formation with no bone fill; BO group (Bio-Oss®, n=10), defects were filled with bovine medullary bone substitute; BF group (Bonefill®, n=10), defects were filled with bovine cortical bone substitute; hydroxyapatite group (HA, n=10), defects were filled with HA; calcium sulfate group (CS , n=10), defects were filled with CS. Five animals from each group were euthanized at 30 and 45 days. The histomorphometry calculated the percentage of the new bone formation in the bone defect. All data obtained were evaluated statistically considering P<0.05 as statistically significant. The results demonstrate the potential of all biomaterials for enhancing bone regeneration. The findings showed no statistical differences between all the biomaterials at 30 and 45 days including the control group without bone grafting. In conclusion, the tested biomaterials presented an estimated capacity of osteoconduction, statistically non-significant between them. In addition, the selection of biomaterial should consider the specific clinical aspect, resorption rates, size of the particle and desired bone healing responses. It is important to emphasize that in some cases, using no bone filler might provide comparable results with reduced cost and possible complications questioning the very frequent use of ridge presentation procedures.