Morphometric and histopathological evaluation of the effect of grape seed proanthocyanidin on alveolar bone loss in experimental diabetes and periodontitis.

OBJECTIVE: Grape seed proanthocyanidine extract (GSPE) is a strong antioxidant derived from the grape seeds (Vitis vinifera, Terral J.F.) and has a polyphenolic structure with a wide range of biological activity. The aim of the present study was to evaluate the effects of GSPE on alveolar bone loss and histopathological changes in rats with diabetes mellitus and ligature-induced periodontitis. MATERIAL AND METHODS: Forty rats were divided into 6 study groups. Control (C, 6 rats) group, periodontitis (P, 6 rats) group, diabetes (D, 6 rats) group, diabetes and periodontitis (D+P, 6 rats) group, diabetes, periodontitis and 100 mg/kg/day GSPE (GSPE-100, 8 rats), and diabetes, periodontitis and 200 mg/kg/day GSPE (GSPE-200, 8 rats) group. Diabetes mellitus was induced by intraperitoneal injection of a single dose of streptozotocin (60 mg/kg). Periodontitis was induced via ligation method. Silk ligatures were placed at the mandibular right first molars. GSPE was administered by oral gavage. After 30 days, all rats were killed. Alveolar bone loss was measured morphometrically via a stereomicroscope. For histopathological analyses, Alizarin red staining, and matrix metalloproteinase (MMP)-8, vascular endothelial growth factor and hypoxia inducible factor (HIF)-1α immunohistochemistry were performed. Tartrate-resistant acid phosphatase-positive osteoclast cells and relative total inflammatory cells were also determined. RESULTS: The highest alveolar bone loss was observed in the D+P group (P < .05). GSP-200 group decreased alveolar bone loss (P < .05). The D+P group had the highest osteoclast counts, but the difference was not significant compared to the P, GSPE-100 and GSPE-200 groups (P > .05). The inflammation in the D+P group was also higher than the other groups (P < .05). The osteoblast numbers increased in the GSPE-100 and GSPE-200 groups compared to the P and D+P groups (P < .05). MMP-8 and HIF-1α levels were highest in the D+P group and GSPE significantly decreased these levels (P < .05). CONCLUSION: Within the limits of this animal study, it can be suggested that GSPE administration may decrease periodontal inflammation and alveolar bone loss via decreasing MMP-8 and HIF-1α levels and increase osteoblastic activity in diabetic rats with experimental periodontitis.

Effect of ozone therapy on autogenous bone graft healing in calvarial defects: a histologic and histometric study in rats.

AIM: The purpose of this study was to analyze histologically the effect of ozone therapy in combination with autogenous bone graft on bone healing in rat calvaria. METHODS: Critical size defects were created in calvaria of 27 male Wistar rats. The animals were divided into three groups of nine animals each: autogenous bone graft group (n = 9); autogenous bone graft with ozone therapy group (80%, 30 s 3 d for 2 wk, n = 9); non-treatment (control) group (n = 9). Animals were killed after 8 wk. Histomorphometric assessments, using image analysis software, and histological analyses were performed. Primary outcome was total bone area. Secondary outcomes (osteoblast number, new bone formation) were also measured. RESULTS: Histomorphometrically, the total bone area in the autogenous bone graft with ozone therapy group (9.3 ± 2.2) were significantly higher than that of the autogenous bone graft group (5.1 ± 1.8) (p < 0.05). Also, the ozone therapy group significantly increased the percentage of total bone area compared to the autogenous bone graft group (p < 0.05). The osteoblast number significantly increased in the autogenous bone graft with the ozone therapy group (58 ± 12.3) compared to the autogenous bone graft group (9.3 ± 3.5) (p < 0.05). Also, it was observed that autogenous bone graft with ozone therapy group showed significant new bone formation when compared to the autogenous bone graft group (p < 0.05). CONCLUSION: Ozone therapy enhances new bone formation by autogenous bone graft in the rat calvarial defect model.