Clear guidance to select the most accurate technologies for 3D printing dental models – A network meta-analysis

•The variety of available printing technologies on the market is rapidly increasing.•One of the most determining factors from a dental aspect is printing accuracy.•3D printed models are widely used in prosthodontics, orthodontics, or implantology.•The accuracy of 3D printed dental models affects the treatment outcome.•SLA, DLP and Ployjet provide the highest accuracy compared to other techniques. Thus far, the findings of numerous studies conducted on the accuracy of three-dimensional (3D) printed dental models are conflicting. Therefore, the aim of the network meta-analysis (NMA) is to determine the accuracy of 3D printed dental models compared with digital reference models. Studies comparing the accuracy of 3D printed full-arch dental models manufactured using different printing techniques to initial STL files were included. This study was registered in PROSPERO (CRD42021285863). An electronic search was performed across four databases in November 2021, and search was restricted to the English language. A systematic search was conducted based on a prespecified search query. 16,303 articles were pooled after the removal of the duplicates. Following study selection and data extraction, 11 eligible studies were included in the NMA in 6 subgroups. The outcomes were specified as trueness and precision and expressed as root mean square (RMS) and absolute mean deviation values. Seven printing technologies were analyzed: stereolithography (SLA), digital light processing (DLP), fused deposition modeling/fused filament fabrication (FDM/FFF), MultiJet, PolyJet, continuous liquid interface production (CLIP), and LCD technology. The QUADAS-2 and GRADE were used to evaluate the risk of bias and certainty of evidence. SLA, DLP, and PolyJet technologies were the most accurate in producing full-arch dental models. The findings of the NMA suggest that SLA, DLP, and PolyJet technologies are sufficiently accurate for full-arch dental model production for prosthodontic purposes. In contrast, FDM/FFF, CLIP, and LCD technologies are less suitable for manufacturing dental models.