치과임프란트 고정체의 형태 및 직경의 차이에 따른 응력 분산의 삼차원 유한요소 분석적 연구

Long-term successful function of a dental implant depends upon biocompatibility of the implant system. Heavy stress may induce the resorption of alveolar bone. Stress analysis using three-dimensional finite element method was applied to compare and analyze the stress produced in adjacent bony tissue and various dental implants. Seven models (Screw type * length 13mm, diameter 3.75mm, 4.0mm, Cylinder type : length 13mm, diameter 3.3mm, 4.0mm, Hollow-basket type • length 13mm, diameter 3.5mm, 4.5mm, 5.5mm) were designed. 10kg of static load was applied to each experimental model. The results were as follows. 1. All the tested implant models showed maximum stress at the cervical portion of the implant with relatively wide and large stress distribution at the apical portion. 2. Heavy shear strength was demonstrated at the cervical portion in screw type 4.0mm and at the apical portion of cylinder type and hollow-basket type implants, indicating an intimate relationship with the shape and diameter of implant system. 3. Different shapes of implants with the same diameter were to have the different area of stress concentration according with the structural characteristics of implants and screw type implants showed relatively stable pattern of stress distribution when compared to other systems. 4. Implants of identical shape with differnet diameters showed similar stress distribution with slight superiority in those of larger diameters. 5. Under the condition of identical bony tissue, increased diameter beyond a certain point resulted in severe stress concentration. 6. Screw-type implant showed the best stress distribution and selectiong the adequate diameter of implant for the remaining alveolar bone is thought to be critical.