Abstract:

Objective To investigate the effect of different structural designs on dimensional stability of 3D printed maxillary resin models. Methods A model scanner was used to scan the standard gypsum dentition model of the upper jaw. Two sets of models with different structural types were designed in the denture design software, including horseshoe-shaped solid model and horseshoe-shaped hollow model. A 3D printer was used to print five resin models each group. On day 1, 2, 3, 5, 7, 14, 21, and 28 after printing, the models were scanned with a 3D model scanner. Saved as the “.stl” file format, the scanned files of the printed models were then performed deviation analysis with the corresponding model design files in Geomagic software. Results The deviation range of the horseshoe-shaped solid models within 28 days was(31.41±4.29)μm to (36.38±3.99)μm. The deviation range of the horseshoe-shaped hollow models within 28 days was(57.36±7.66)μm to(97.64±27.14)μm. The deviation of the 3D printed resin models made with two structural designs was less than 100 μm. There was no statistical difference between the accuracy of the horseshoe solid group within 28 days of printing and the first day(P>0.05). There was a statistical difference between the accuracy of the 7th day after the printing of the horseshoe hollow group and the first day(P<0.05). With the extension of storage time, the deformation of the horseshoe-shaped hollow models became more and more obvious. Conclusion 3D-printed resin dental models with the horseshoe solid structure design have excellent long-term dimensional stability. The resin models of the hollow design of the horseshoe structure have good dimensional stability within 7 days after printing.

Key words: structural design, 3D printing, resin dental model, deviation analysis, dimensional stability