교정적 치아 이동 후 재발에 대한 백서 모델 확립을 위한 예비 연구: Elastomeric Power Chain vs. Ni-Ti Coil Spring

Abstract

This study aims to establish experimental animal models for orthodontic tooth movement and orthodontic relapse using an elastomeric power chain and nickel-titanium (Ni-Ti) coil spring, which are most commonly used in clinical practice. The amount of orthodontic tooth movement and relapse in rats according to the two materials was measured, and the histological differences and the expression of molecules involved in bone turnover were compared. Two female Sprague-Dawley rats were induced orthodontic tooth movement for 14 days by applying orthodontic materials to right and left maxillary first molars. 7 days after the device removes, the relapse rate and the effect on periodontal tissue were evaluated through tooth movement, micro-CT taking, hematoxylin and eosin (H&E) and tartrate-resistant acid phosphatase (TRAP) staining, and immunohistochemistry (IHC) analysis. The result of measuring the relapse rate on the 7th day after applying orthodontic force for 14 days was measured as 60.7% and 77.8% in the E.B and C.S groups, respectively. As a result of analyzing the root furcation area of the maxillary first molar, the E.B group tend to show a smaller BV/TV value than the C.S group, but the values of other parameters were similar. The number of TRAP-positive osteoclasts was higher on the compression side than on the tension side, and there was no significant difference between the two groups. The OPG, RANKL, and sclerostinpositive cells measured on the compression side also showed no significant difference. In the experimental model using the elastomeric power chain, no evidence was found that it was inaccurate or more inflammatory than the Ni-Ti coil spring model, and when considering the hygiene and convenience of the subject, it was suitable for use in the model.