Abstract
It has been known that zinc is a very important essential trace element. In the present study, forty 5-week-old male Wistar rats were divided randomly into four groups as the control (34.4 ppm) group, zinc deficient diet (0%: 3.7 ppm) group, low zinc diet (50%: 14.7 ppm) group and high zinc diet (150% 51.4 ppm) group. We aimed at observing the effect of zinc on the ultrastructure alteration of enchondral ossification in the mandibular condyle of growing rats. We obtained the following results.
1) There were more osteoblasts found in the high zinc diet group than that in the low zinc diet group. The number of active osteoblast decreased in the zinc deficient diet group, and it increased in the order of the low zinc diet group, high zinc diet group and control group. In the zinc deficient diet group, the numbers of osteoblast and osteoclast decreased clearly.
2) In contrast to the control group, osteocytes in the zinc deficient diet group were surrounded by many collagen fibrils and the inactive osteoblast were often noted which showed the bone formation was inactive. Compared to the zinc deficient diet group, the bone formation and the differentiation from osteoblast to osteocyte were more active in low zinc diet group. In the high zinc diet group, the active osteoblast showed active bone formation.
These findings suggested that zinc plays an important role in the morphologic feature in the enchondral ossifacation in the mandibular condyle of growing rats.
