Clinical evaluation of posterior ceramic crowns made using CAD/CAM technology

INTERVENTION: This is a randomized, controlled, double‐blind, longitudinal clinical study in which 60 posterior single‐unit crowns will be fabricated for volunteer participants requiring restorative treatment with single‐unit fixed dental prostheses in posterior teeth. Participants will be randomly allocated into two groups by a randomization process, with distribution between the control group and the experimental group. Control group: 30 posterior single‐unit crowns fabricated from lithium disilicate using computer‐aided design and computer‐aided manufacturing. Experimental group: 30 posterior single‐unit crowns fabricated from ultratranslucent zirconia using computer‐aided design and computer‐aided manufacturing. Masking will be double‐blind, involving participants and clinical evaluators, who will not be aware of the ceramic material used in each crown. The procedures will include clinical screening, participant selection, initial assessment, tooth preparation, fabrication and placement of provisional restorations, fabrication of monolithic ceramic crowns using computer‐aided design and computer‐aided manufacturing, assessment of marginal and internal misfit by the replica technique, cementation of definitive crowns, and clinical, esthetic, periodontal, and quality‐of‐life follow‐up. Evaluations will be performed at the initial period, after placement of provisional restorations, one week after placement of the definitive crown, one month, si Xmonths, and one year after cementation, including analysis of restoration clinical longevity, restoration color, occlusal surface, marginal discoloration, marginal integrity, ceramic fracture, debonding, periodontal parameters, esthetic satisfaction, and impact on quality of life CONDITION: Crowns; Dental Porcelain ; Dental Prosthesis E06.780.346 PRIMARY OUTCOME: Expected outcome 1: It is expected to evaluate the clinical longevity of posterior single‐unit monolithic crowns fabricated from lithium disilicate and ultratranslucent zirconia using computer‐aided design and computer‐aided manufacturing, assessed by the modified United States Public Health Service criteria at 1, 6, 12, and 24 months after cementation Found outcome 1: A cumulative survival rate of 100% was observed for lithium disilicate crowns and 100% for ultratranslucent zirconia crowns after 24 months of follow‐up, assessed by Kaplan‐Meier survival analysis and compared by the log‐rank test, with no statistically significant difference between groups INCLUSION CRITERIA: Volunteer participants; both sexes; age 18 years or older; need for restorative treatment with single‐unit fixed dental prosthesis in posterior teeth; presence of a posterior tooth indicated for a single‐unit full crown; good general health conditions; availability to attend clinical appointments and follow‐up visits; agreement to participate in the study by signing the Free and Informed Consent Form SECONDARY OUTCOME: Expected outcome 2: It is expected to evaluate the clinical performance of posterior single‐unit monolithic crowns fabricated from lithium disilicate and ultratranslucent zirconia, considering restoration color, occlusal surface, marginal discoloration, marginal integrity, ceramic fracture, debonding, and secondary caries, using the modified United States Public Health Service criteria at 1, 6, 12, and 24 months after cementation Expected outcome 3: It is expected to evaluate the esthetic satisfaction of participants rehabilitated with posterior single‐unit monolithic crowns fabricated from lithium disilicate and ultratranslucent zirconia, using a visual analog scale applied before treatment and at 1, 6, 12, and 24 months after cementation Found outcome 2: No ceramic fractures, occlusal surface changes, marginal integrity failures, secondary caries, or crown debonding were observed during the 24‐month follow‐up. Slight marginal discoloration was observed in one ultratranslucent zirconia crown, without the need for restoration replacement and without being considered a clinical failure Found outcome 3: A significant improvement in esthetic satisfaction was observed over time in both groups, with a p value lower than 0.05. No statistically significant difference was observed between groups for any esthetic criterion at any follow‐up period, with a p value greater than 0.05