Dimensional stability of maxillary casts made from plant-based resins and additively manufactured with different...

Plant-based resins have emerged as environmentally sustainable alternatives in dental additive manufacturing. However, information on their clinical applicability is limited, particularly when different additive manufacturing technologies are used.

The purpose of this in vitro study was to compare the dimensional stability of additively manufactured maxillary casts using plant-based and conventional dental cast resins and different 3-dimensional (3D) printers over 4 weeks.

The scan file of a dentate maxillary typodont model was used to fabricate diagnostic casts from soy-based (SB), corn-based (CB), and conventional (KM) resins using either a digital light processing (DLP) or liquid crystal display (LCD) 3D printer (n=10). Each cast was scanned with a laboratory scanner the day after fabrication and weekly for 4 weeks. The scan files were superimposed over the reference file using a 3D analysis software program to calculate root mean square (RMS) values (anterior, posterior, entire arch, soft tissue, and entire cast). Statistical analysis was performed using a generalized linear model (α=.05).

Dimensional stability was affected by resin, printer, and their interaction (P≤.004). Storage duration and its interactions did not affect the dimensional stability (P≥.471). In the anterior region, SB casts printed with the DLP printer had the lowest RMS, while those printed with the LCD printer had the highest (P<.001). For other regions, CB casts printed with the DLP printer mostly had the lowest RMS, whereas SB casts printed with the LCD printer mostly had the highest (P≤.023).

The CB casts printed with the DLP printer exhibited dimensional stability comparable with or higher than that of the KM casts printed with the same printer. One month of storage time did not substantially affect the dimensional stability of the tested casts.