The objective of this study was to assess the accuracy and feasibility of three-dimensional(3D)printing dental models based on Digital Light Processing (DLP)used for the fabrication of clear aligners in mild malocclusions.

Twenty patients with different types of simple irregularities were selected and intra-oral scanned for the digital dental models with 3shape Trios. The 3shape Ortho Analyzer software was used to setup the digital models and the tooth movement staging. The step model data were derived for 3D printing and aligner fabrication. Eighty-five upper and lower jaw dentition digital models and 3D-printed models were compared digitally or manually with the selected corresponding crown height, crown width, arch width and length measurements to test the consistency and accuracy of the 3D-printed model. The intraclass correlation coefficients(ICC)was used to evaluate the reliability of the two measurement methods.Paired t tests were used to detect significant differences in the measurements between the 3D-printed models and the original digital models.

The intraclass correlation coefficients for all the comparisons made between the 3D replicas and the original digital models were greater than 0.95. This indicated an excellent agreement. No statistically significant differences could be detected between the 3D-printed models and their corresponding digital models except for crown height measurements. The overall difference was ranging from (-0.01±0.12) mm to (0.11±0.31) mm.

The accuracy of the 3D models produced by the DLP techniques at 10μm layer heights for the fabrication of clear aligners in mild malocclusions was clinically acceptable.

Three-dimensional printing; Dental model; Digital model; Clear aligners