Zirconia restoration types, properties, tooth preparation design, and bonding. A narrative review

Abstract

Objective: The purpose of this review was to provide dental professionals with information regarding the various types of zirconia restorations, their mechanical and optical properties, tooth preparation design, and bonding protocol in an effort to enhance the longevity and durability of zirconia restorations.

Overview: The yttria content of zirconia ceramics determines their classification. The mechanical and optical properties of each type are discussed, with an emphasis on the effect of yttria concentration on the properties of zirconia. The processing and sintering methods are also discussed as they have a direct impact on the properties of zirconia. The design of tooth preparation, specifically occlusal reduction, varies depending on the type of zirconia used in each case. Finally, a protocol for zirconia restoration bonding is described to ensure optimal bonding to the tooth structure.

Conclusion: Not all zirconia restorations are the same. The selection of zirconia type based on yttria concentration, processing and sintering methods, tooth preparation design, and adherence to the bonding protocol are all critical to the success and longevity of zirconia restorations.

Clinical significance: Zirconia restorations are the most commonly used indirect restorative material. The selection of the most appropriate zirconia type based on its yttria content, which determines its strength and translucency, is critical to the success and the longevity of the restoration. Tooth preparation design also influences the strength and translucency of the zirconia. Air-borne particle abrasion, followed by a ceramic primer and resin cement, can ensure a durable bond to the tooth structure.

Keywords: ceramics; operative dentistry; properties; prosthodontics; restorative dentistry; zirconia.

FIGURE 1

(A) Cast post and core (teeth #s 5–7, and 10–12) that was restored for demonstration purposes with a 5Y zirconia fixed dental prosthesis (10–12) (B) to show lack of ability to mask dark underlying structure. (C) 3Y zirconia fixed dental prosthesis (10–12) was used as final restoration, which shows its capability of masking dark underlying structures.