Comparison of fit accuracy of pressed lithium disilicate inlays fabricated from wax or resin patterns with conventional and CAD-CAM technologies

• Published in: The Journal of prosthetic dentistry 2018-10, Vol.120 (4), p.530-536
• Main Authors: Homsy, Foudda R., Özcan, Mutlu, Khoury, Marwan, Majzoub, Zeina A.K.
• Format: Article
• Language: English
• Subjects: Ceramics - therapeutic use; Computer-Aided Design; Dental Impression Materials - therapeutic use; Dental Impression Technique; Dental Marginal Adaptation; Dental Materials - therapeutic use; Dental Porcelain - therapeutic use; Dental Prosthesis Design - methods; Dentistry; Humans; In Vitro Techniques; Inlays; Resins, Synthetic - therapeutic use; Waxes - therapeutic use
• ISSN: 0022-3913; 1097-6841
• DOI: 10.1016/j.prosdent.2018.04.006

The use of resin patterns to produce partial coverage restorations is poorly documented. The purpose of this in vitro study was to compare the marginal and internal fit accuracy of lithium disilicate glass-ceramic inlays obtained from wax or resin patterns and fabricated with digital and conventional techniques. A dentoform mandibular first molar was prepared for a mesio-occlusal ceramic inlay. Six groups of 15 inlays were obtained by conventional impression and manual wax (group CICW) or resin patterns (group CICR); conventional impression, laboratory scanning of the stone die, CAD-CAM milled wax (group CIDW), or polymethylmethacrylate (PMMA) blocks (group CIDR); and scanning of the master preparation with an intraoral scanner, CAD-CAM milled wax (group DSDW), or PMMA blocks (DSDR). The same design was applied to produce the wax and PMMA patterns in the last 4 groups. The replica technique was used to measure marginal and internal fit under stereomicroscopy. Mixed-model ANOVA was applied to assess differences according to the techniques, materials, and discrepancy location (α=.05). The results demonstrated significant effects of the technique (P