Impact of 3D printing orientation on accuracy, properties, cost, and time efficiency of additively manufactured dental models: a systematic review.

Background: The evidence on the effect of printing orientation on dimensional accuracy and properties of resinous dental models is unclear. This systematic review aimed to assess the impact of printing orientation on the accuracy and properties of additively manufactured resinous dental models, besides the cost, material consumption, and time efficiency at different orientations.

Methods: A comprehensive web search (PubMed, Scopus, Cochrane) was performed in July 2024 without language restrictions. The included studies were assessed using the modified consort statement for laboratory studies on dental materials. The outcomes were accuracy and surface quality, besides the cost and time efficiency of additively manufactured dental models printed in different directions.

Results: Following PRISMA guidelines, 14 records were included. Most records favored horizontally printed models with minor controversies regarding accuracy, material consumption, time, and cost efficiency. While orientation can influence surface quality, it is often more significantly affected by factors such as the printing technology used, the material properties, and the layer thickness.

Conclusions: Horizontal orientation has proven to be the most efficient for producing dental models, particularly for single-model manufacturing, due to its superior time and cost savings. However, large-scale and overnight massive production favors the vertical orientation since the platform accommodates twice to triple the models' numbers as horizontal orientation. The majority of studies favor horizontal orientation for its accuracy. Choosing the optimal orientation in additive manufacturing not only ensures precision of dental models, improving the fit of restorations and prostheses, but also leads to significant reductions in production time, material usage, and energy consumption, ultimately minimizing environmental impact.

Trial registration: Not applicable.