Marginal gap and fracture resistance of implant-supported 3D-printed definitive composite crowns: An in vitro study. (September 2022)

• Record Type: Journal Article
• Authors: Donmez, Mustafa Borga; Okutan, Yener
• Is Part Of: Journal of dentistry. Volume 124(2022)
• Publication Date: 2022-09
• Subjects: 3D-printing -- Fracture resistance -- Implant-supported crown -- Marginal gap; Dentistry -- Periodicals; Dentistry -- Periodicals; Dentisterie -- Périodiques; Electronic journals; 617.6005
• DOI: 10.1016/j.jdent.2022.104216
• Languages: English
• ISSNs: 0300-5712

Abstract

Highlights: 3D printed implant-supported composite crowns presented lower marginal gap values than clinically acceptable threshold. 3D printed implant-supported composite crowns could endure occlusal forces of the posterior region. Abstract: Objectives: To compare the marginal gap and fracture resistance of implant-supported 3-dimensional (3D) printed definitive composite crowns with those fabricated by using 3 different millable materials. Material and methods: A prefabricated abutment was digitized by using a laboratory scanner (E4 Lab Scanner) and a complete-coverage maxillary first premolar crown was designed (Dental Designer). Forty crowns were fabricated either by 3D printing (Saremco Print Crowntec, SP) or milling (Brilliant Crios, BC; Vita Enamic, VE; Cerasmart 270, CS) ( n = 10). Baseline marginal gap values were evaluated by measuring 60 predetermined points on an abutment (15 points for each side) with a stereomicroscope at ×40 magnification. Marginal gap values were reevaluated after adhesive cementation. Load-to-fracture test was performed by using a universal testing machine. Two-way analysis of variance (ANOVA) was used to evaluate the effect of material type and cementation on marginal gap values. While Tukey HSD tests were used to compare the materials' marginal gap values before and after cementation, the effect of cementation on marginal gap values within each material was analyzed by using paired samples t-tests. Fracture resistance data were analyzed by using 1-way ANOVA (α=0.05). Results: Material type and cementation significantly affected marginal gap values ( P < .001). Regardless of cementation, SP had the lowest marginal gap values ( P < .001), while the differences among milled crowns were nonsignificant ( P ≥ .14). Cementation significantly increased the marginal gap values ( P < .001). Material type did not affect fracture resistance values ( F = 1.589, P = .209). Conclusion: Implant-supported 3D-printed composite crowns showed higher marginal adaptation compared with the milled crowns before and after cementation. In addition, all crowns endured similar forces before fracture.