Impact of digital dentistry in daily prosthodontics

The goal of this Ph D thesis was to evaluate the impact of new digital technologies in the field of prosthodontics and to assess the advantages and disadvantages of them through in vivo and in vitro studies to implement their use in everyday practice. Firstly, in vitro studies for fixed and removable prosthodontics were conducted to test the devices and materials in laboratory without variables and potential confounding factors present in whole organisms and to evaluate parameters before testing them in vivo. Different intraoral scanners have been tested to assess the accuracy in terms of trueness and precision in different possible clinical scenarios: vertical or horizontal finish line designs, supra or subgingival margins, implant scanbodies. Additionally in vitro studies assessed also the outcomes of a completely digital workflow: from digital intraoral impression of abutments with two different intraoral scanners to the final milled lithium disilicate complete crowns that have been evaluated in terms of accuracy of marginal and internal fit. From these studies emerged a high accuracy of intraoral scanners when used for detecting vertical iuxta or supragingival margins and good fit of the milled restorations. Since the positive outcomes of in vitro studies, in this thesis in vivo protocols have been performed thorough three different Randomized Controlled clinical trials. Clinical research lays the groundwork for progress in medicine and is an indispensable prerequisite for evidence-based medicine. Randomized controlled clinical trials (RCTs) are the gold standard for ascertaining the efficacy and safety of a treatment or device. As reported in the present thesis , it emerged that there aren9t any statistically significative differences between traditional, hybrid or digital workflows for the realization of partial restorations or veneers. Additionally traditional pressed lithium disilicate partial restoration have been compared with UHPHS evaluation criteria to milled ones and to 3D printed PMMA restorations and no statistically significative difference was found. This RCT studies have reported encouraging results regarding the new materials tested and digital workflow but longer periods of follow up and larger sample are needed to confirm the present data. Regarding removable prosthodontics, interesting flexural strength values of printable resins emerged when compared to milled and traditional ones. Additionally, two different case reports have been conducted to report the clinical performances of cad-cam milled complete dentures realized with a completely digital workflow that highlighted once again the advantages of using intraoral scanners and new prosthodontics material in a completely digital workflow.