Digital scanning for complete-arch implant-supported restorations: A systematic review

Scanning of completely edentulous arches remains a challenge because of the large surface to scan and the lack of anatomic indexes. Whether the presence of impression transfer copings with digital scanning provides enough markers for acceptable precision and clinical use has not been determined.The purpose of this systematic review was to assess the accuracy of digital scanning for complete-arch implant-supported restorations.A systematic review of peer-reviewed literature was conducted to analyze articles published between 2008 and 2019. Among the 208 retrieved articles, 20 were selected for review.Five articles reported the use of digital scanning in clinical situations and satisfying short-term results. Fifteen in vitro studies were also included for complementary information, including measurement accuracy. Most of the intraoral scanners used in vitro provided acceptable accuracy below a threshold of 150 μm. When directly compared, the digital technique was at least equivalent to conventional impression techniques.In vitro, intraoral scanners have shown acceptable accuracy. The main parameters identified for their influence on precision were interimplant distance, body scan design, scanning pattern, and operator experience. Clinical evidence is limited by the lack of a definitive method of assessing the fit of the framework.