齒科用 石膏가 家兎의 顎骨損傷部 治癒에 미치는 影響

THE EFFECT OF PLASTER OF PARIS ON THE HEALING PROCESS OF BONY DEFECT IN RABBITS

The purpose of this experimental study was to observe the rate of resorption, tissue tolerance and influence of Plaster of Paris in the healing process of bony defect after implantation of Plaster of Paris in the mandible of rabbits. Twenty four hybrid white rabbits were divided into two groups; Experimental group was implanted with Plaster of Paris (measured diameter 4㎜, height 5㎜), and control group was filled with blood in the bony cavity. Each of the experimental and control animals were sacrificed on the 1st, 2nd, 3rd, 4th, 5th, 6th weeks postoperation and mandible was removed. After radiograph taking with dental periapical film, specimens of experimental group were fixed in 10% neutral formalin solution for 24 hours and decalcified with nitric acid mixed with formalin (1:9). And then embedded in paraffin, sectioned into 6μ thickness and stained H-E stain. The results of study were as follows: In the radiographic examination, Implanted Plaster of Paris resorbed partially on 1st week but complete resorption was occurred on 2nd weeks. Experimental group revealed more radiopacity in the bony defect than control group through 6 weeks. In the histopathologic examination. Localized inflammatory foreign body giant cell appeared on 2nd week. Calcium substance in the Plaster of Paris deposited on the new bone and pre-existing undamaged bony spicules from 4th week. Bony defect was almost filled with new bone on 6th week.