PURPOSE: . The aim of this study was to introduce rating criteria to evaluate student performance in a newly developed, digital wax-up preclinical program for computer-aided design (CAD) of full-coverage crowns and preliminarily investigate the reliability and internal consistency of the rating system. MATERIALS AND METHODS: . This study, conducted in 2017, enrolled 47 fifth-year dental students of Okayama University Dental School. Digital wax-up training included a fundamental practice using computer graphics (CG), multipurpose CAD software programs, and an advanced practice to execute a digital waxup of the right mandibular second molar (#47). Each student’s digital wax-up work (stereolithography data) was evaluated by two instructors using seven qualitative criteria. The total qualitative score (0-90) of the criteria was calculated.The total volumetric discrepancy between each student’s digital wax-up work and a reference prepared by an instructor was automatically measured by the CAD software. The inter-rater reliability of each criterion was analyzed using a weighted kappa index. The relationship between the total volume discrepancy and the total qualitative score was analyzed using Spearman’s correlation. RESULTS: . The weighted kappa values for the seven qualitative criteria ranged from 0.62 - 0.93. The total qualitative score and the total volumetric discrepancy were negatively correlated (ρ = -0.27, P = .09, respectively); however, this was not statistically significant. CONCLUSION . The established qualitative criteria to evaluate students’ work showed sufficiently high inter-rater reliability; however, the digitally measured volumetric discrepancy could not sufficiently predict the total qualitative score.

Objective：This study was aimed at investigating the acquirement of socks-handling ability with hip flex, abduction, and external rotation position (hip open position) in 5 months after the posterior approach to total hip arthroplasty (THA), with consideration of the functional goals by conducting a multicenter cooperative study.Methods：The study included 101 patients (104 hip joints) with hip osteoarthritis. We evaluated patient attribution；ranges of motion of the hip, knee and ankle；hip pain in socks-handling；and upper extremity length, which were evaluated before the operation, upon hospital discharge and at 5 months after the posterior approach to THA. The patients were classified into those who attained and did not attain socks-handling ability in open hip position until 5 months after THA. We investigated the factors for acquiring socks-handling ability by using a multiple logistic regression analysis.Results：We identified three factors that significantly correlated to socks-handling ability as follows：(1) socks-handling ability before the operation, (2) range of hip external rotation before operation, and (3) range of hip abduction before discharge. The goal to acquire socks-handling ability is 27.5°hip external rotation and 17.5°hip abduction.Conclusion：We suggest that socks-handling ability must be acquired before THA and that the target range of hip abduction and external rotation must be attained during the early post-THA stage.

Objective：This study was aimed at investigating the acquirement of socks-handling ability with hip flex, abduction, and external rotation position (hip open position）in 5 months after the posterior approach to total hip arthroplasty (THA), with consideration of the functional goals by conducting a multicenter cooperative study.Methods：The study included 101 patients (104 hip joints) with hip osteoarthritis. We evaluated patient attribution；ranges of motion of the hip, knee and ankle；hip pain in socks-handling；and upper extremity length, which were evaluated before the operation, upon hospital discharge and at 5 months after the posterior approach to THA. The patients were classified into those who attained and did not attain socks-handling ability in open hip position until 5 months after THA. We investigated the factors for acquiring socks-handling ability by using a multiple logistic regression analysis.Results：We identified three factors that significantly correlated to socks-handling ability as follows：(1) socks-handling ability before the operation, (2) range of hip external rotation before operation, and (3) range of hip abduction before discharge. The goal to acquire socks-handling ability is 27.5° hip external rotation and 17.5° hip abduction.Conclusion：We suggest that socks-handling ability must be acquired before THA and that the target range of hip abduction and external rotation must be attained during the early post-THA stage.