Reliability of measurements made on scanned cast models using the 3 Shape R 700 scanner.

OBJECTIVES: In dentistry, the latest technological advancements have been incorporated primarily into diagnostic tools such as virtual dental models. The aim of this study was to evaluate the reliability of measurements made on digital cast models scanned in the 3 Shape R 700 scanner (3 Shape, Copenhagen, Denmark) that uses a non-destructive laser beam to reproduce model surfaces so that the plaster model is not destroyed. METHODS: The sample consisted of 26 cast models, and 6 linear measurements were made on the cast models and compared with the same measurements on digital models. The measurements assessed were: (1) distance between mandibular canines; (2) distance between mandibular molars; (3) distance between canine and maxillary molar; (4) buccal-lingual diameter of maxillary central incisor; (5) distance between two points of the incisive papillae of maxillary and mandibular central incisors; and (6) distance between the buccal surface of the maxillary central incisor and the buccal surface of the mandibular antagonist (overjet). The Student's t-test or Wilcoxon test was used at 5% and the Lin's concordance test at 95% confidence interval. RESULTS: The overjet measurement was the only one that showed a statistically significant difference (p < 0.05). A high level of concordance was found for all measurements. CONCLUSIONS: The digital models obtained from the 3 Shape R 700 scanner are reliable and can be considered an alternative to cast models for performing measurements and analyses in orthodontic practice.