Comparison of DLP and LCD 3D printing technologies: effects on denture base accuracy, weight, residual material,...

The aim of this study was to compare the geometric accuracy, weight, residual material, and fabrication time of complete denture bases produced at different build orientations using Digital Light Processing (DLP) and Liquid Crystal Display (LCD) technologies.

An edentulous maxillary model (Frasaco B-3 NH,Germany) was scanned by using an extraoral scanner (7Series Dentalwings,Straumann,Montreal,Canada) and a 2mm-thick reference denture base was designed (Exocad DentalCAD 3.1,Germany). The base was manufactured by using resin-based 3D printing technologies such as DLP (n= 35) (Sega Pro, DentaFAB, Istanbul, Türkiye) and LCD(n = 35) (Whale 3Ultra 14K,Nova 3D,Shenzhen,China) at building angles of 0°, 45°, and 90°, oriented labially, buccally, and palatally. For each 3D printing technology, seven different production types were considered based on build angles and orientations (for DLP and LCD technologies: 0° single; 45° and 90° in buccal, labial, and posterior positions). A minimum of five specimens per production type was included, resulting in a total of at least 70 denture base specimens in the study. All bases were scanned and compared with the reference model. Geometric deviations were evaluated using a metrology software (Geomagic Control X,3D Systems, South Carolina,USA). Material consumption and residual amounts were calculated by measuring the masses of the materials before and after manufacturing using a precision balance with 0.001 g sensitivity (Radwag, Radom, Poland). The fabrication duration for each specimen was recorded. Statistical analyses were performed using one-way ANOVA to compare build orientations within each technology, independent samples t-tests to compare DLP and LCD systems for each orientations, and two-way ANOVA to assess interaction effects between manufacturing method and build orientation (α = 0.05).

Denture bases fabricated using DLP technology exhibited higher geometric accuracy, lower weight, and less residual material compared to those produced with LCD technology (p < 0.001). The highest precision was observed at the Labial 45° and Labial 90° orientations, while the greatest deviation occurred at the Buccal 90° orientation (p < 0.001). Two-way ANOVA indicated that the interaction between manufacturing method and build orientation was significant for all measured parameters (p < 0.001). Additionally, DLP technology demonstrated shorter fabrication time (p < 0.001) and lower resin consumption (p = 0.007), indicating a more efficient production process.

DLP printing of denture bases provides a viable and clinically acceptable method, offering reduced material waste and shorter production times compared to LCD. Build orientation also significantly affects accuracy, emphasizing the importance of optimizing printing parameters. Overall, DLP printing appears to be an efficient and clinically promising approach for denture base fabrication.

This study demonstrates that optimizing the build orientation and printing angle in additive manufacturing significantly influences the production accuracy of complete denture bases. Among the tested techniques, DLP printing showed superior performance by providing higher geometric accuracy, reduced material waste, and shorter production times compared to LCD. These findings highlight the importance of selecting the appropriate build orientation and printing method, making this study a valuable guide for achieving the most accurate denture base fabrication in clinical practice.