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 3Shape R700 scanner (3Shape, 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 3Shape R700 scanner are reliable and can be considered an alternative to cast models for performing measurements and analyses in orthodontic practice. Dentomaxillofacial Radiology (2015) 44, 20140337. doi: 10.1259/dmfr.20140337 Cite this article as: Lemos LS, Rebello IMCR, Vogel CJ, Barbosa MC. Reliability of measurements made on scanned cast models using the 3Shape R700 scanner. Dentomaxillofac Radiol 2015; 44: 20140337.

Skeletal malocclusions may be due to disturbances in the growth of the mandible or maxilla. In most cases, discomfort is the result of tooth-to-tooth malocclusion or tooth-to-soft-tissue contact. Currently, in veterinary medicine, these problems are treated palliatively. In humans, orthognathic surgery is indicated to correct severe skeletal malocclusions, offering aesthetic and functional benefits to the patients. This research evaluated the effects of an intra-oral mandibular sagittal split osteotomy in 20 dog cadavers with skeletal malocclusion. After sagittal osteotomy and mandibular repositioning, the osteotomies were fixed with titanium mini-plates and 1.5 mm diameter screws or 1.5 mm bicortical screws. The statistical analysis revealed a significant occlusion difference in the treated cadavers (Wilcoxon test, p<0.05). In 19/20 cadavers there was correction of the angular osteotomy while the mandibular alveolar vessels and nerve were preserved during osteotomy and fixation in all cadavers. In conclusion, intra-oral mandible sagittal osteotomy allowed correction of malocclusion in cadavers. However, it would be important to prepare a preoperative orthodontic-surgical treatment plan to obtain a satisfactory occlusion during the surgery in clinical patients.