Precision and trueness of dental models manufactured with different 3-dimensional printing techniques

In this study, we assessed the precision and trueness of dental models printed with 3-dimensional (3D) printers via different printing techniques.

Digital reference models were printed 5 times using stereolithography apparatus (SLA), digital light processing (DLP), fused filament fabrication (FFF), and the PolyJet technique. The 3D printed models were scanned and evaluated for tooth, arch, and occlusion measurements. Precision and trueness were analyzed with root mean squares (RMS) for the differences in each measurement. Differences in measurement variables among the 3D printing techniques were analyzed by 1-way analysis of variance (α = 0.05).

Except in trueness of occlusion measurements, there were significant differences in all measurements among the 4 techniques (P <0.001). For overall tooth measurements, the DLP (76 ± 14 μm) and PolyJet (68 ± 9 μm) techniques exhibited significantly different mean RMS values of precision than the SLA (88 ± 14 μm) and FFF (99 ± 14 μm) techniques (P <0.05). For overall arch measurements, the SLA (176 ± 73 μm) had significantly different RMS values than the DLP (74 ± 34 μm), FFF (89 ± 34 μm), and PolyJet (69 ± 18 μm) techniques (P <0.05). For overall occlusion measurements, the FFF (170 ± 55 μm) exhibited significantly different RMS values than the SLA (94 ± 33 μm), DLP (120 ± 28 μm), and PolyJet (96 ± 33 μm) techniques (P <0.05). There were significant differences in mean RMS values of trueness of overall tooth measurements among all 4 techniques: SLA (107 ± 11 μm), DLP (143 ± 8 μm), FFF (188 ± 14 μm), and PolyJet (78 ± 9 μm) (P <0.05). For overall arch measurements, the SLA (141 ± 35 μm) and PolyJet (86 ± 17 μm) techniques exhibited significantly different mean RMS values of trueness than DLP (469 ± 49 μm) and FFF (409 ± 36 μm) (P <0.05).

The 3D printing techniques showed significant differences in precision of all measurements and in trueness of tooth and arch measurements. The PolyJet and DLP techniques were more precise than the FFF and SLA techniques, with the PolyJet technique having the highest accuracy.