Evaluating the local and systemic effects of silicon dioxide on healing of mandibular bone in rabbits

The study aimed to evaluate and compare the local and systemic effects of silica(SIO2) on healing of bony defect of mandibular bone in rabbit. Thirty-six white Albino healthy male adult rabbits with the same weight, age, and circumstance of feeding and housing were used in this study. All animals were submitted to operation in the mandibular bone region. A hole of 2mm diameter and 4mm depth was drilled by heavy–duty dental engine. The rabbits were divided into three groups(12 rabbits/group)each group were subdivided into three experimental periods(7,14,28 days)three rabbits for each period as follows: Control group, n=12(hole was not filled by anything),locally treated group n=12(silica powder was condensed well in the hole) and systemically treated group n=12 (hole was not filled by anything but the rabbits received dietary supplement of 2mg/kg of silica daily). Biochemical, histological and histomorphometric analysis were measured after scarifying the animals at 7,14,28 days respectively. Histological study showed increases in bone healing criteria like granulation tissue and new bone formation in both treated groups in comparison with the control group. Histomorphometric analysis showed a significant increase in the number of osteoblasts and thickness of bone trabeculae in treated groups comparing with the control group, while a significant decrease in the number of osteoclast, and in all these results systemically treated group is superior over the locally treated group. Biochemical analysis showed a significant increase in BALP in the systemically treated group compared with the control. This study concluded that silicon was successfully accelerating bone healing when used topically and systemically and the optimal response was obtained when it is given as a daily dietary supplement.