Comparative Analysis of 3D-Printed and Milled Zirconia in Dental Clinical Applications

Abstract

This review aimed to compare the efficacy of 3D-printed (AM) versus milled (SM) zirconia restorations concerning clinical outcomes, internal gaps, trueness, precision, and biocompatibility. The study conducted a thorough search of online databases up to April 2024, identifying studies comparing AM and SM zirconia restorations across various parameters. Out of 165 records, 55 met the eligibility criteria, with 42 included for review. Quality assessment utilized the revised Cochrane risk-of-bias tool (ROB2) and the Modified Consort Statement, revealing moderate to low risk in clinical studies and identifying bias concerns in laboratory studies. Short-term observations indicated a 100% survival rate with no periodontal complications. 3D-printed zirconia crowns exhibited lower ΔE values and better conformity to adjacent teeth compared to milled crowns. In terms of aesthetics, 3D-printed crowns offered superior color and contour matching with adjacent natural teeth. Both techniques yielded restorations with acceptable internal and marginal fit, although milled crowns tended to have smaller marginal gaps, still within clinical acceptability. 3D printing showed promise for laminate veneers and demonstrated better axial surface trueness than conventionally milled surfaces.Long-term randomized controlled trials are needed to confirm the clinical suitability of 3D-printed restorations. In summary, adequate internal fit and gap, precision, and trueness are vital for successful dental restorations. Both 3D printing and milling techniques produce restorations with clinically acceptable marginal and internal fit. Notably, 3D printing shows advantages for axial surfaces and narrow areas compared to conventional milling methods.