Dealing with the Internal and External Surfaces of Zirconia Restorations; between Past and Present Trends. A Review of Literature

Abstract

Objectives:The optimum zirconia bonding protocol have been always a mystery to be solved throughout the past years. The purpose of this review is to go through the innumerable surface treatment methods and protocols concerned with the both internal and external zirconia surface treatment.Study selection, Data and Sources: An electronic Pubmed, Medline and Google scholar search was done to attain In-vitro studies on zirconia surface treatments published in english, with time frame between 2013 and 2020.Results: Hundred thirty-two in vitro studies and systematic reviews were surveyed in this appraisal. Numerous techniques were used for zirconia surface modifications, these methodologies were categorized and grouped in this review according to the surface modified. Laboratory test studies discuss internal surface treatments including micro-mechanical bonding, chemical bonding and external surface treatment including different core surface treatment, glazing and polishing. Conclusions:With respect to the heterogeneity of the included studies; the internal surface treatment, most of the included studies verified the air particle abrasion as the generally approved micro-mechanical topographic modification protocol. Other internal surface treatment protocols as chemical etching showed promising results in laboratory studies with inadequacy of clinical application.The external surface studies verified different methods over others. However, self-glazed zirconia studies are scarce.

Intraoral Repair of Dental Ceramics Using Er,Cr:YSGG Laser: Review

“…To form a chemical bond with silane, Z-prime is used to create a chemical link with zirconia because it includes 10-MDP phosphate ester monomer, which chemically binds with the oxide layer of zirconia and increases bond strength. (El-Ashkar and Nabil 2022) Other published research, however, has shown that the use of a laser does not improve the adhesion of composite resins and zirconia.…”

Investigation of the effect of different experimental acid solutions applied on the zirconia surface on the bond strength between zirconia and resin cement: A pilot study

“…This increase may also be attributed to the hydroxylation on the surface, and the acid solutions might have contributed to the micromechanical retention by increasing the micro-roughness of the zirconia (30). The objective of the hydroxylation was to enhance the bond strength between zirconia and the resin cements by increasing the concentration of OHgroups on the zirconia surface (18,19). Nevertheless, these applications may not be suitable for clinical use mainly because they contain hazardous acids that might be toxic (18).…”

“…The objective of the hydroxylation was to enhance the bond strength between zirconia and the resin cements by increasing the concentration of OHgroups on the zirconia surface (18,19). Nevertheless, these applications may not be suitable for clinical use mainly because they contain hazardous acids that might be toxic (18). They may be suitable only for laboratory usage with proper safety protocols, including adequate ventilation and personal protective equipment (18).…”

“…Nevertheless, these applications may not be suitable for clinical use mainly because they contain hazardous acids that might be toxic (18). They may be suitable only for laboratory usage with proper safety protocols, including adequate ventilation and personal protective equipment (18).…”

“…Due to these drawbacks, attempts to strengthen the bonding of the resin cement continue to be enhanced. There have been reports stating that combining sulfuric acid with hydrogen peroxide (H2O2), known as the "Piranha solution" (3H2SO4:1H2O2), can enhance the bonding strength of resin cement to zirconia (18,19). Some studies utilizing hot chemical etching (20), which uses HF acid solutions in different ratios and requires a heat treatment with an acidic solution, have shown promising results (21).…”