Performance of posterior 3D printed resin-matrix ceramic crowns fabricated in a fully digital workflow: a two-year prospective clinical study

To evaluate the survival and success rates, as well as mechanical and biological outcomes of posterior 3D-printed resin-matrix ceramic crowns in a fully digital workflow over a 2-year follow-up. A prospective clinical trial was conducting involving 30 posterior crowns fabricated from a resin-matrix ceramic using DLP 3D-printing technology. Dental preparations were performed and scanned with an intraoral scanner by a single operator. All crowns were cemented using the same dual-curing resin cement. Clinical performance was assessed using California Dental Association (CDA) criteria. Periodontal parameters (plaque index, gingival index and probing depth) were evaluated with a periodontal probe at cementation and at 6-month, 1-year, and 2-year recall appointments on abutment teeth and contralateral or antagonistic uncrowned natural teeth used as controls. Data were analyzed using Wilcoxon signed rank test and Kaplan–Meier survival analysis. The 2-year survival rate was 93%, and the success rate was 87%. Two crowns debonded, and no biological complications were observed. All crowns remained within the satisfactory range after 2 years. A slight yellow shift was detected in 4 crowns, resulting in a significant color change at 2 years (p = 0.046), while all other CDA parameters remained unchanged. The margin remained stable throughout the observation period. Plaque index increased after one year in the abutment and control teeth. Within the limitations of this study, including the absence of a control group, 3D-printed resin-matrix ceramic crowns may represent a viable alternative for posterior teeth. Long-term studies are required to confirm these results. Posterior 3D-printed resin–matrix ceramic crowns within a fully digital workflow demonstrated satisfactory performance after two years, supporting their potential as a viable option for posterior restorations.