In modern restorative dentistry, the emphasis has shifted toward minimally invasive approaches to manage tooth wear, particularly on occlusal surfaces, while conserving healthy tooth structure. Biocorrosion, caused by chemical, biological, and electrochemical interactions (e.g., dietary acids, GERD), is now a major contributor to tooth wear alongside abrasion and attrition. These conditions can impair aesthetics, reduce vertical dimension, and compromise oral function and quality of life.

Historically, full-coverage crowns following elective root canals were the standard treatment, but they involve significant tooth reduction and associated complications. In contrast, partial coverage restorations like inlays, onlays, overlays, and occlusal veneers have emerged as conservative, biomechanically favorable alternatives.

Occlusal veneers—also known as tabletop restorations—are especially useful for severe occlusal wear. They preserve enamel and require proper bonding protocols and material selection to ensure long-term success. Among restorative materials:

• Lithium disilicate ceramics (e.g., IPS e.max Press) offer a balance of strength, esthetics, and reliable bonding.

• Zirconia-reinforced lithium silicate ceramics (e.g., Celtra Press) provide enhanced strength and crack resistance with good bonding and optical properties.

  While promising, most data on material performance come from in vitro studies, and there’s a lack of robust  clinical comparisons. Therefore, this study aims to evaluate the clinical performance, survival and complications of lithium disilicate vs. zirconia-reinforced lithium silicate occlusal veneers in vivo.