DEPROTEINIZED BOVINE BONE GRAFT REMODELING PATTERN IN ALVEOLAR SOCKET. HISTOLOGIC AND IMMUNOHISTOLOGICAL EXPRESSION EVALUATION.

Deproteinized bovine bone (DBB) is a bone graft highly used in dentistry in bone regeneration and alveolar socket preservation techniques. Although there is a scientific consensus on the clinical benefit of this biomaterial, and several in vitro studies described its biologic effect on osteoblasts, in vivo analyses investigating its effect on bone dynamics on human are lacking. For this purpose 20 patients needing tooth extraction and implant placement were selected and randomized in test (alveolar socket preservation with DBB) and control (spontaneous healing). Bone specimens were collected during tooth extraction (T0) and, at 5 months, during implant placement (T1). The collected samples were processed for histologic and immunohistological analyses to reveal the presence of positive (BMP-2, BMP-7, ALP) and negative (Il-6, TNF-\u3b1) markers of bone remodeling. The sections were then micro-photographed, quantification was done and statistical analyses were performed to compare T0 and T1 in both groups and T1 test group versus T1 control group. The obtained results showed higher expression of BMP-2, BMP-7 and IL-6 at T1 in both groups (p<0.05), lower expression of ALP in both (p<0.05) at T1 and higher expression of TNF-\u3b1 only in test group (p<0.05) while in control group it remained stable during time. When comparing T1 markers expression in control and test groups, a higher expression of BMP-2 (p<0.05) and lower expression of TNF-\u3b1 (p