Tribological aspects of enamel wear caused by zirconia and lithium disilicate: A meta-narrative review.

The contact between enamel and an antagonist surface is the primary factor in tooth wear. Loss of tooth structure can cause changes in occlusion, chewing functionality, dental sensitivity, and appearance. However, enamel wear caused by opposing restorations is multifactorial and there is a lack of consensus regarding its behavior. This meta-narrative review assesses the multiple factors that affect enamel wear when using two common indirect restorative materials, lithium disilicate and zirconia. PubMed, Google Scholar, MEDLINE, and CINAHL databases were searched using keywords "zirconia," "lithium disilicate," "antagonistic tooth wear," and "enamel wear" to identify studies related to enamel wear caused by zirconia and lithium disilicate restorations. The Realist and Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES) publication standard was used to report this meta-narrative literature review. Four broad categories of influencing factors were identified and reviewed: (1) mechanical and physical properties, (2) wear behavior and microstructural characteristics, (3) surface state, and (4) environmental factors. We conclude that well-polished zirconia is a more favorable indirect restorative material than lithium disilicate in terms of tribology because of its microstructure and surface integrity during wear. This review will enable clinicians to better comprehend the intricate nature of tooth wear caused by dental restorations.