Diagnostic Esthetic Functional Splint (DEFS) as a removable CAD/CAM prototype to assess the final prosthetic rehabilitation: a review

The main purpose of the current review was to provide an overview of DEFS (Diagnostic Esthetic Functional Splint), consisting of tooth-colored, “snap-retained” devices. DEFS are CAD/CAM produced, available by materials exhibiting a certain degree of elasticity (like polycarbonates or acetal resins), and are valuable to restore function, esthetics, and occlusion in several clinical situations. The search strategy included all papers available in electronic databases (PubMed/Medline, Evidence-Based Dentistry, BMJ Evidence-Based Medicine, Dynamed, Embase, BMJ Clinical Evidence, Web of Science, Scientific reports) and those dealing with CAD/CAM manufactured, tooth-colored, snap-retained prosthetic devices; eligible papers were researched on the website www.opengrey.eu and a manual search was also performed. From the electronic databases 13,199 records were retrieved, many of which were duplicates. The grey literature and the manual research did not produce any eligible articles. After removing duplicate articles, 7,690 records were obtained. Titles, abstracts, and keywords were analyzed. The studies concerning the topic of interest were examined by the reviewers and discussed. Although no long-term clinical study was found in the literature, the DEFS devices exhibit many advantageous clinical characteristics and may represent the most proper solution in several difficult cases, especially when fixed prosthodontic solutions are questionable or cannot be achieved. Therefore, the DEFS procedure and materials should be further investigated in the future through long-term follow-up studies, in order to get a significant evaluation of the effectiveness and performance of this typology of dental devices.