Variations in orthodontic treatment planning decisions of Class II patients between virtual 3-dimensional models and traditional plaster study models

Abstract

Study models provide invaluable information in treatment planning. Digital models have proved to be an effective measurement tool, but their use in treatment planning has not been studied. Ten sets of records of Class II malocclusion subjects (dental study models, lateral cephalograms/tracings, panoramic radiographs, intraoral and extraoral photographs) were used for treatment planning by 20 orthodontists on 2 separate occasions. Digital models were used to evaluate the patients at 1 session and plaster models were used at the other session. Treatment recommendations were scored and compared for agreement. Eleven orthodontists served as the control group, looking at the records on 2 occasions with plaster models for agreement. Good agreement was noted for surgery (P = 1.00, kappa = 0.549), extractions (P = .360, kappa = 0.570), and auxiliary appliances (P = 1.00, kappa = 0.539) for the digital/plaster group. Agreement in the plaster/plaster group for surgery (P = 1.00, kappa = 0.671), extractions (P = 1.00, kappa = 0.626), and auxiliary appliances (P = .791, kappa = 0.672) was also good. Overall proportions of agreement ranged between 0.777 and 0.870 for digital/plaster and 0.818 and 0.873 for plaster/plaster. There was no statistical difference in intrarater treatment-planning agreement for Class II malocclusions based on the use of digital models in place of traditional plaster models. Digital orthodontic study models (e-models) are a valid alternative to traditional plaster study models in treatment planning for Class II malocclusion patients.