LCD-based DLP printers: a simplified construction compared with conventional 3D printers with projection technology

Background: Three-dimensional (3D) printing has found several applications in dental technology. Printers based on digital light processing (DLP) offer great accuracy, excellent surface properties and a wide range of printing materials. To simplify the construction, the liquid crystal display (LCD)- based printer, a developed version of DLP printers, uses an LCD panel as exposure mask by means of an ultraviolet (UV) light source. Materials and methods: This study compared 20 standardised test specimens and one working model printed with a conventional DLP printer (projection technology) with models printed using LCD-based technology. The objects were examined microscopically regarding surface properties and peculiarities of the layering and were measured with a digital calliper. Results: Microscopically, both systems showed excellent surface quality. Small fluctuations in the z-axis were found in the objects printed using the LCD technology. The measurements showed deviations of 0.06 to 0.13 mm from the computeraided design (CAD) construction for both systems. Conclusions: Printing results of LCD printers were similar to those of DLP printers. Due to its early development stage, further improvements in the mechanical stability and slicer software are required. Parole chiave: 3D-printer, accuracy, digital light processing (DLP), LCD