Abstract: Objective: To study the morphological stability of photosensitive resin dental models made from different three-dimensional printing materials. Methods: Resin dental models made from two types of 3D-printed materials were printed, namely FHD1400 group (10 sets) and E-Model-Light group (10 sets). All models were scanned by an optical model scanner instantly after printed and after 1, 3, 7, 14, 28, and 60 days of storage. The heat map was generated by superimposing models at different time points. The average deviation and deformation percentage were calculated, meanwhile, changes of four linear indexes (the anterior, middle, and posterior width and length of the dental arch) of the model were measured. The data were statistically analyzed and the differences were compared among the models. Results: The resin dental model shrunk more with the extension of storage time. The average deviation, deformation percentage, and contraction of arch length and width increased rapidly within 14 days. The width contraction between molars of all models exceeded 0.2 mm after 14 days of storage. Conclusion: The resin dental models printed from two commonly used clinical materials have poor morphological stability and should not be used longer than 14 days after printing. The morphological stability of E-Model-Light group was better than that of FHD1400 group.

Key words: three-dimensional printing, photosensitive resin, dental models, morphological stability