Prevalence and causes of indirect veneer failure: a retrospective analysis from a university dental hospital

Indirect veneers are widely used as an esthetic restorative option in dentistry however, complications may occur leading to failure and the need for replacement. Understanding the prevalence and contributing factors to veneer failure is essential for proper diagnosis and for improving clinical outcomes. This study aimed to assess the prevalence, patterns, and causes of indirect veneer failures among patients receiving replacement restorations at the Dental University Hospital, King Saud University, Riyadh, Saudi Arabia. A retrospective analysis was conducted on 194 replaced veneer restorations. Data extracted from patient records included patient demographics, tooth location, type of failure, survival duration, veneer material, cement type, and preparation design. Descriptive statistics and cross-tabulations were used to evaluate failure distribution across clinical and material-related variables. Associations between all variables were assessed using the Chi-square test. A p-value < 0.05 was considered statistically significant. Veneer failure was more common in females (79.9%) than males (20.1%). Failures occurred more frequently in posterior teeth (65.5%) and in the maxilla (57.7%). Age-related peaks were observed at 44 years (20.6%), 38 years (10.3%), and 47 years (10.3%). Most failures occurred after 6-7 years of service. The most frequent cause was dimensional error in veneer size or shape (58.2%), followed by discoloration (21.1%). Lithium disilicate veneers accounted for the highest proportion of replacements in the study sample (64.4%), porcelain was more fracture-susceptible (10.3%), and zirconia showed higher debonding and shade mismatch (8.3% each). Failures were most common in veneers with incisal edge coverage (36.6%), followed by prep-less (32.5%) and minimal preparation designs (30.9%). Indirect veneer failures were predominantly associated with dimensional complications and discoloration, especially in lithium disilicate restorations and designs involving incisal edge coverage. These findings highlight the importance of careful case selection to enhance long-term veneer success.