Abstract
BACKGROUND: Zirconia ceramic materials have become a preferred choice for anterior teeth, but their marginal performance under thermocycling has not been sufficiently investigated. Thus, this in vitro study aims to compare the impact of thermocycling on the marginal discrepancy of zirconia computer-aided design/computer-aided manufacturing (CAD/CAM) generation on maxillary central incisors. MATERIALS AND METHODS: A total of 36 zirconia central incisor crowns were fabricated using three different CAD/CAM systems (ZirCAD Prime, Cercon ht ML, Zolid Bion; 12 per group) and cemented onto models made from resin. After aging for 48 hours in artificial saline, the crowns underwent thermocycling for 10,000 cycles. Marginal discrepancies were measured at two points on four sides per specimen under a digital microscope at 40× magnification. Data were analyzed using analysis of variance (ANOVA) and t-tests, and a p-value of ≤ 0.05 was considered statistically significant for all tests. RESULTS: Before thermocycling, the ZirCAD Prime group demonstrated the lowest overall mean and standard deviation (SD) marginal discrepancy values (55.76 ± 16.41 µm), followed by Zolid Bion (60.95 ± 16.64 µm) and Cercon ht ML (62.93 ± 20.79 µm). After thermocycling, the ZirCAD Prime group demonstrated the lowest discrepancy in overall mean and standard deviation (57.18 ± 16.43 µm), followed by Zolid Bion (62.92 ± 16.31 µm) and Cercon ht ML (63.83 ± 20.92 µm). ANOVA revealed no significant difference in the zirconia groups before (p ≥ 0.688) and after (p ≥ 0.681) thermocycling. However, paired t-tests indicated significant differences in discrepancies before and after thermocycling for all materials (p < 0.001). CONCLUSION: After thermocycling, all types of CAD/CAM zirconia crowns showed an increase in marginal discrepancies, but these differences remained within clinically acceptable limits. HOW TO CITE THIS ARTICLE: Alshehri AH. The Impact of Thermocycling on the Marginal Discrepancy of Zirconia CAD/CAM Generation on Central Incisors: An In Vitro Study. Int J Clin Pediatr Dent 2025;18(9):1146-1152.