The advent of additive manufacturing has transformed restorative dentistry, offering clinicians alternative methods for the fabrication of crowns and bridges that are faster, less wasteful, and potentially more precise than conventional techniques. Stereolithography (SLA), digital light processing (DLP), and masked LCD printing are examples of 3D printing technologies that have shown great promise in creating both temporary and permanent restorations with acceptable mechanical characteristics and fit precision. This study comprehensively evaluates the longevity, marginal and internal fit accuracy, and workflow efficiency of 3D-printed crowns and bridges compared with traditional milled ceramics and indirect fabrication methods. Laboratory simulations of masticatory loading, thermocycling, and fracture resistance testing were conducted on 120 restorative units, including single crowns, three-unit bridges, and long-span restorations, produced using both additive and subtractive manufacturing approaches. Results indicated that 3D-printed restorations achieved clinically acceptable marginal adaptation and internal fit within standard thresholds, with DLP printers outperforming SLA and LCD systems in precision. Longevity analysis revealed that while printed resins exhibited lower long-term mechanical endurance compared with milled zirconia and lithium disilicate, they remained suitable for short- to medium-term definitive applications, particularly in low- to moderate-occlusal load scenarios. In conclusion, 3D printing represents a viable and efficient alternative for the fabrication of single-unit crowns and short-span bridges, offering advantages in chairside efficiency, cost reduction, and predictable fit.
