Fabrication systems for restorations and fixed dental prostheses made of titanium and titanium alloys

Purpose: In recent years, the application of restorations and fixed dental prostheses to molars by computer-aided design-computer-aided manufacturing (CAD/CAM) with composite resin has been increasing. Titanium and titanium alloy having a high tissue affinity and good biocompatibility are suitable for cases where CAD/CAM fabrications are inadequate, such as allergic reaction to metal. Many studies have reported methods of production with titanium and titanium alloys. The purpose of this review is to survey the clinical application of titanium and titanium alloy restorations and fixed dental prostheses with various fabrication systems. Study selection: A literature search in PubMed was performed for various fabrication systems of titanium and titanium alloy from 2010 through 2019. The search keywords were "titanium", "titanium alloy", "CAD/CAM", "cast", "fabrication system", "marginal gap", "internal gap", and "clinical performance". Only relevant studies are summarized and discussed in this review. Results: With any fabrication system, titanium and titanium alloy restorations and fixed dental prostheses fabricated with various systems were within the clinically acceptable ranges of marginal gap and internal fit. Additionally, these restorations were considered to have less effect on the periodontal issues. Although metal-ceramic restoration has clinical performance problems, such as ceramic fracture, fabrications with only titanium and titanium alloy were reported to have good clinical performance. Conclusions: Regardless of the fabrication system, titanium and titanium alloy restorations and fixed dental prostheses can be applied clinically. Titanium and titanium alloys are thought to be a promising alternative to the dental metals currently used. (C) 2019 Published by Elsevier Ltd on behalf of Japan Prosthodontic Society.