Comparative Evaluation of Occlusal Wear of Two Types of Zirconia Crowns and Opposing Natural Teeth: A Split-Mouth Clinical Study

Background: Tooth wear is a multifaceted issue influenced by various factors contributing to enamel loss, altered vertical dimension, masticatory difficulties and aesthetic concerns, highlighting the importance of material selection in restorative dentistry. Aim: The aim of this study was to evaluate and compare the wear of high translucent and super high translucent zirconia crowns and the antagonist natural teeth at time intervals of 1 week,3 months and 6 months. Study Setting and Design: In vivo study. Materials and method: Twenty patients were selected and divided into two groups of 10 each.  Group A: High Translucent (Zolid HT+) and Group B: Super High Translucent (Zolid FX Multilayer).  After tooth preparation, casts at 1 week, 3 months and 6 months were prepared and scanned with 3D white light scanner (Smart SCAN 3D HE Scanner, Spectrum). Wear pattern of the high translucent, super high translucent and antagonist natural teeth were evaluated with High Resolution Optical profilometer at 1 week, 3 months and 6 months follow up visits.  Statistical analysis used: The statistical software SPSS 16.0 was used for analysis of data.  The test of significance difference of mean wear between two materials (Inter-group comparison) was tested by one way ANOVA and for various pairs repeated measures of ANOVA (RMA) followed by Bonferroni test. Level of statistical significance was kept at p<0.05. Results: The results indicated a significant difference in wear of Super High Translucent Zirconia crowns and High Translucent zirconia crowns across all time intervals (p<0.05).  There was a statistically significant increase in wear of enamel opposing Super High Translucent Zirconia as compared to High Translucent zirconia (p<0.05).  Conclusion: It was concluded that wear of Super High Translucent Zirconia crowns is more than that of High Translucent zirconia crowns.  The wear of antagonist natural teeth is more with Super High Translucent Zirconia crowns than with High Translucent crowns. Hence, use of Super High Translucent Zirconia Crowns, if needed, should be restricted to regions with high aesthetic demand and less occlusal forces.