Enamel wear against monolithic zirconia restorations: A meta‐analysis and systematic review of in vitro studies

Abstract

Objective An assessment was performed to identify and evaluate dental enamel wear caused by monolithic zirconia restoration. Literature searches were conducted in PubMed, Science Direct, Cochrane Evidence, and the Cochrane Library up to May 2020. Material and methods Studies were selected for systematic review according to the inclusion (articles conducted on the wear of enamel samples opposing monolithic zirconia) and exclusion (case reports, non‐English articles, and monolithic zirconia samples facing other materials rather than human enamel) criteria. Of those, articles on polished and glazed monolithic zirconia subjected to a 50 N vertical load with a range of 240,000–250,000 cycles, equivalent to 1 year of in vivo mastication, were included in the meta‐analysis. Results In total, 3968 articles were pooled. Twenty‐five articles met the inclusion criteria for the systematic review. Three studies were included in the meta‐analysis. The results showed that the enamel wear against monolithic zirconia was within the statistically accepted level. Moreover, the polished monolithic zirconia surface caused less enamel wear than the glazed surface. Conclusion This review indicates that monolithic zirconia restorations cause acceptable antagonist enamel wear. Moreover, the meta‐analysis results agreed that the final restoration's surface texture plays an essential role in the wear process. Clinical significance Monolithic zirconia restorations have been widely used in dental practice because they eliminate the chipping problems resulting from using veneered restorations. With recent technology development, monolithic zirconia has obtained more esthetic features and a more natural look. However, due to the high strength and surface roughness of monolithic zirconia, wear on the antagonist's teeth was detected. The results showed that this wear amount was statistically acceptable and lower than other ceramics such as feldspathic porcelain and enamel. Furthermore, surface treatment methods must be applied to minimize tooth wear, as polished or glazed surfaces interfere with enamel loss.

Wear Behaviour of Polymer-Infiltrated Network Ceramics, Lithium Disilicate and Cubic Zirconia against Enamel in a Bruxism-Simulated Scenario

“…However, the zirconia tested by Habib et al was multi-layered, with a high amount of cubic phase, which is more prone to mechanical degradation and might lead to less uniform prism exposure and a consequent superficial roughness increase, which, therefore, explains the higher wear induced by this material compared with that obtained in the present study [24]. This was also confirmed by Sripetchdanond et al [13], who concluded that the materials inducing the least wear to enamel were RBC and zirconia, as well as different reviews that showed how zirconia has friendly wearbehaviour against enamel [14][15][16]. The present results were also confirmed by Ludovichetti et al [11], who reported a high abrasiveness of lithium disilicate, while nanofilled RBC and PINC were more antagonist-friendly.…”

“…Consistencies were reported by Habit et al [ 12 ], who found higher wear of the enamel when matched with zirconia. In contrast, different Authors [ 13 , 14 , 15 , 16 ] found different results, showing how zirconia produced less antagonist wear in comparison with PINC materials. These inconsistencies within apparently similar in vitro studies may be related to the different testing procedures adopted, as well as to the different polishing treatments of each material.…”

Wear Behavior between Aesthetic Restorative Materials and Bovine Tooth Enamel

“…In laboratory studies, enamel wear by polished zirconia-based materials was less than or comparable to tooth–tooth contact; however, the wear behavior was dependent on the surface topography of the restorations [ 16 , 17 ]. In a previous systematic review [ 18 ], it was reported that there was no significant difference in the opposite enamel wear between zirconia-based materials and enamel in vitro. Moreover, in clinical studies, enamel wear by zirconia-based materials is larger than or comparable to tooth–tooth contact [ 9 , 19 , 20 ].…”

Wear of Polymer-Infiltrated Ceramic Network Materials against Enamel

“…Therefore, the wear property of crown-restorative materials is an important mechanical property for the long-term clinical success of tooth restoration. For dental CAD/CAM ceramics, numerous in vitro studies have been conducted to examine the wear behaviors of dental-restorative materials under simulated oral environments by comparing each material combination [ 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 ]: Ceramic vs. enamel antagonist, ceramic vs. ceramic antagonist, and enamel vs. enamel antagonist. Many studies have been conducted on the wear behavior of ZIR and LDS.…”