Comparative evaluation of the marginal fitness of vonlay nanoceramic hybrid restorations using different computer-aided imaging techniques: an in-vitro study

Purpose The purpose of this in-vitro study was to evaluate the marginal fitness of vonlay nanoceramic hybrid restorations using different computer-aided imaging technique (an in-vitro study). Materials and methods Thirty 3D printed models of prepared premolar (no. 14) for vonlay restoration were fabricated using epoxy resin material and used for fabrication of thirty nanohybrid ceramic vonlays (Grandio Disc, VOCO). three groups (n = 10) of vonlays were fabricated using three different imaging technique: group 1: imaging of conventional impression of master die, group 2: imaging of stone master die and group 3: imaging of master die using chairside TRIOS Intraoral Scanners (3Shape). Vonlays were designed by using a CAD design software program (Exocad Dental CAD, Exocad. The vonlays were cemented over their corresponding dies with an automix dual cure adhesive cement system (Duo-Link universal resin cement, Bisco Inc.) under a static load by using custom made seating device. Digital microscope was used to measure the vertical marginal gap for each where a total of 120 measurements for the three groups (12 sites per vonlay and 10 vonlays per group) were evaluated. One-way analysis of variance test was used to analyze the results, Student sample t test was used to examine the marginal gap differences of each group and in the same group. Results A significant difference (P < 0.001) was found between the marginal gap values of the vonlay restoration fabricated by using different imaging technique. The smallest marginal gaps were obtained with vonlay fabricated using chairside intraoral scanners as compared with imaging of master die impression and stone master die. But there was no significant difference between the marginal gap measurements of different sides in the same group. Conclusion The smallest marginal gaps were obtained with vonlay fabricated using chairside intraoral scanners.