The Effects of Fluoride and Calcium on the Periodontal Tissue of Rats treated with Dihydrotachysterol

Abstract

The effects of fluoride and calcium (combind therapy) on periodontal tissue treated with Dihydrotachysterol (DHT) were studied in rats.
Sprague-Dawley strain female rats, weighing about 140 grams were divided into 5 groups:
(1) Normal group (un-treated), (2) Experimental group 1: DHT-treated group, (3) Experimental group 2: DHT-treated plus fluoride, (4) Experimental group 3: DHT-treated plus calcium, and (5) Experimental group 4: DHT-treated plus fluoride and calcium.
DHT was administered daily for 20 days at a dose of 50μg per 100g body weight, and fluoride (0.11mg of NaF) or calcium (1mg of calcium lactate) was injected subcutaneously from the 21th to 25th day.
The results were as follows:
The body weight of the DHT-treated group dropped until the 5th day but afterwards leveled off and then markedly increased from the 21th day to the end of the experiment.
Serum calcium levels were increased and mandibular bone calcium levels were markedly decreased in the experimental groups compared with the untreated group, but the mandibular bone calcium level of experimental group 4 was less reduced than the experimental group 1 when compared with the untreated group.
On the other hand, serum phosphorus was slightly increased in experimental groups 2 and 4, while mandibular bone phosohorus was unchanged.
Concerning histological changes, a layer of eosinophlic substance (osteoid and cementoid-like substance) was observed in the root central area and in the root apex area on the alveolar bone and cementum surface in the DHT-treated groups.
Therefore the periodontal ligament space was narrowed, and the arrangement of periodontal fibers was irregular.
In experimental groups 2 and 4, the eosinophilic substance on the surface of the alveolar bone and cementum was reduced, thus enlarging the periodontal ligament space.
Especially, a marked reduction of eosinophilic substance was seen in experimental group 4.
No changes were observed in the eosinophlic substance and the periodontal ligament space in experimental group 3.