Purpose: To compare the implant replica position accuracy on a duplicated complete edentulous maxillary implant definitive cast made either using conventional procedures or material jetting additive manufacturing (AM) technology using a coordinate measuring machine (CMM). Material and methods: A complete edentulous maxillary cast with 6 implant replicas was prepared. The definitive cast was duplicated using two manufacturing procedures namely conventional (CNV group) and additive manufacturing procedures (AM group). On the CNV, an AM Co-Cr framework and a custom AM custom tray with a polyether impression material were used to obtain an impression of the definitive cast at room temperature (23°C). On the AM group, the definitive cast was digitized using a laboratory scanner. The standard tessellation language (STL) file was exported and used to manufacture the polymeric AM specimens using a multijet printer following manufacturer´s recommendations. A new digital implant replica was located on each corresponding housing of each AM specimen. A total of 10 specimens per group was obtained. A CMM was selected to measure the position of each implant replica on the definitive cast, CNV, and AM specimens. Linear and angular discrepancies were computed for each specimen. Thus, the Mann Whitney U test was used to analyze the data (p = 0.05). Results: There was no significant difference in x-, y-, and z-linear and XZ angular discrepancy between both groups. However, the AM group revealed a significantly higher median YZ angular discrepancy than the CNV group (p = 0.007). Conclusions: Material jetting AM technology demonstrated no significant difference in trueness and precision values of the linear and angular implant replica positions when compared to the conventional technique.

149Resumo O fluxo de trabalho digital em odontologia permite o processamento digital completo da restauração começando com a impressão digital usando um scanner intraoral até a fabricação da peça final. Os avanços recentes nas tecnologias de impressão 3D abriram novas possibilidades também para os técnicos em prótese dentária através dos quais os procedimentos de cera e fundição nos laboratórios poderiam ser eliminados. Neste relato de caso clínico, descreve-se uma técnica onde o padrão foi fabricado usando a fabricação de aditivos para restaurações do tipo onlay em dissilicato de lítio injetadas. ABsTRACTThe digital workflow in dentistry allows for complete digital processing of the restoration starting with the digital impression using an intraoral scanner to until the fabrication of final reconstruction. Recent advances in 3D printing technologies opened new possibilities also for dental technicians through which wax-up and casting procedures in the laboratories could be eliminated. In this clinical report, a technique is described where the pattern was fabricated using additive manufacturing for pressed lithium disilicate onlay restorations.