Same as medicine, orthodontic doctors needed to collect lots of patients’ data to conclude the problem list. Then, they could decide the diagnosis and the treatment plan. The data collected might be from the questionnaire and interview, clinic examinations, and diagnostic records. Along with the development of computer technique, digitization was a trend unable to stop. Now, most medical records were recorded, stored and managed in digital form. For orthodontic diagnosis and treatment plan, digital photography and digital radiography had been taken many years. The digital dental models developed recently might replace the cast models in dentistry. The purpose of this study was to assess the difference between the digital dental models and cast models, and the possibility that the digital replace the cast models.
28 sets of cast models were scanned using the VIVID 9i laser digitizer. The digital model were produced and measured by the Rapidform 2006 software. 14 parameters were measured and the study was divided into 2 groups (intra-examiner and inter-examiner). The results were analyzed by paired t test and the P value was 0.05.
The result of intra-examiner group indicated that there was no significant difference in most parameters between digital models and cast models. The result of inter-examiner group indicated that there was significant difference in almost 1/3 parameters between digital models and cast models.
Comparing to cast models, there were lots of advantage using digital models. But the equipments were too expensive. In inter-examiner group, although there was significant difference between digital models and cast models, the difference among examiners was lager. That indicated the difference was not clinically significant. Measuring tools and the quality of images were the main cause of the difference between digital models and cast models. According to the parameters we measured, digital models and cast models were not clinic different.
