A 3-year controlled clinical trial comparing high-translucency zirconia (cubic zirconia) with lithium disilicate glass ceramic (e.max)

Abstract

Introduction: The rate of clinical success in veneers, under esthetics, has achieved a range of 18 months to 20 years. In a plethora of studies, it registers a success rate reaching 75% and even 100%. The most common type of glass ceramics used in ceramics is the vitreous lithium disilicate crystal-reinforced material, e.max®. Recent studies focus on "polycrystalline ceramic use" in manufacturing veneers, as it possesses a stronger structure and different enabling manufacturing schemes.

Objectives: This research aims at comparing e.max and the high-translucent Cubic Zirconia. Such comparison is administered to veneers manufacturing: esthetic (surface and edge, and staining and color matching), functional (crack and fracture, contact point, and patient satisfaction), and biological (posttreatment vitality and hypersensitivity, and periodontal response).

Materials and methods: The research sample consisted of 60 veneers, divided into two groups: cubic zirconia and e.max. The sample included 2 males (16.6%) and 10 females (83.3%), with age ranging from 25 to 37 years. Patients were thoroughly diagnosed and treated and included in this study based on certain inclusion-exclusion criteria. Hickel's 2010 criteria were utilized to examine and observe the clinical aspect of veneers during intervals of 1 week, 3 months, 1 year, and 3 years.

Results: No significant differences were traced across the groups for all the variables, with a p-value being greater than 0.05. The e.max group revealed better clinical results compared to the cubic zirconia one regarding esthetics and tooth translucency. Nonetheless, the results showed a merely slight increase in hypersensitivity in the e.max group.

Conclusion: Within the limitation of an extensive follow-up period, we can conclude that there is no difference between cubic zirconia and e.max (p > 0.05), where e.max and cubic zirconia veneers have the same characteristics in terms of the following. The characteristics of the aspects examined were esthetic, functional, and biological.

Keywords: e-max; gingivitis; translucent zirconia; veneers.