I-bar 클래스프의 위치가 지대치의 치주인대에 미치는 유한요소법적 응력 분석

Abstract

The purpose of this study was to analyze stress using the 3-dimensional finite element method for the effect of the position of I-bar clasp on the lateral and dislodging force occurring at the functional movement of the distal extension removable partial denture. The experiment model was composed of the compact bone, the cancellous bone, the tooth structure, the pulp and the periodontal ligament. The first and second premolars on the mandible were selected and used in 3-dimensional finite element analysis model. The structure of the splinted abutment was simplified for comparison with independent natural teeth, and the enamel of the teeth was restored with gold alloy of type Ⅲ according to the American Dentist Standards. The load of 5N was applied at 45° toward the occlusal surface to each of the mesial part, the highest contour of the buccal surface (center) and the distal part corresponding to 1/3 of the cervix of the crown of the abutment. Load of the same condition was also applied to the gold crown of the splinted abutment. The results were as follows: 1. Stress on the periodontal ligament of the independent second premolar was low in the order of the distal part(0.2515 Mpa), the highest contour of the buccal surface(0.2583 Mpa) and the mesial part(0.2763 Mpa) according to the position of the I-bar clasp tip. 2. In the splinted teeth, stress on the periodontal ligament of the second premolar was low in the order of the highest contour of the buccal surface, the mesial part and the distal part. 3. Stress was much lower and the distribution of stress was also more better in the splinted abutment than in the independent one. In conclusion, considering force applied in the direction of the tissue, the position the I-bar clasp tip resisting force applied in the direction opposed to the tissue should be the highest contour of the buccal surface of independent or splinted abutment for the protection of the abutment and the splinting of abutment is considered significantly advantageous for the distribution of load.