HISTOLOGICAL AND ULTRASTRUCTURAL EFFECT OF ZINC SULPHATE SUPPLEMENTATION ON THE ALVEOLAR BONE OF CALCIUM DEFICIENT RATS

Objective: The aim of the present study was to investigate the efficiency of zinc sulphate supplementation in treatment of the alveolar bone osteoporosis in rats induced by calcium
deficient diet.
Design: Thirty adult male Wistar rats with an average weight of 200-250 grams were randomized into 3 groups. Group Ι (control group): received standard rat chow, Group ΙΙ (osteoporotic group): received calcium deficient diet and Group ΙΙΙ (zinc treated group): received calcium deficient diet plus oral supplementation of zinc sulphate. After 3 months, the rats were sacrificed. The mandibles were examined histologically, histomorphometrically, ultrastructurally and by energy dispersive
X ray microanalysis (EDX).
Results: Histologically the impaired bone quality induced by calcium deficiency were significantly improved by zinc supplementation. The alveolar bone restored its structural organization in form of thick bone trabeculae, decrease number of osteoclasts and regularly distributed osteocytes. Histomorphometric analysis showed significant reduction in area percentage of alveolar bone trabeculae in osteoporotic group (p<0.001), while zinc treated group showed significant increase in the area percentage of bone compared to the osteoporotic group (p<0.001). Ultrastructurally, surface roughness and irregularity of the buccal cortical plate were observed in osteoporotic group. However, zinc treated group showed smooth and regular bone surface with minor irregularities. EDX microanalysis indicated a significant decrease in calcium content in osteoporotic group (p<0.001), while zinc treated group showed significant increase in the calcium percentage of bone compared to the osteoporotic group (p<0.001).
Conclusions: In a rat model zinc supplementation prevents the bone loss induced by calcium deficient diet.