Laboratory examination of cement thickness for zirconia and composite inlays cemented with two types of fixing agents

Abstract

INTRODUCTION: During last decades glass ionomer (GICs) have shown an improvement in handling, less polymerization time, increasing the durability and better wear resistance. Resin composites cements are low viscosity composite materials. They are recommended for cementing ceramic and indirect composite restorations. The zirconia ceramics are not capable of etching for the purposes of cementation with composite fixing agents. AIM: The aim of this article is to make a comparison assessment of the two types fixing agents used for the cementation of indirect aesthetic restorations using zirconium dioxide made via CAD/CAM technology and indirect composite. MATERIALS AND METHODS: An experimental study of inlays-60 made of indirect composite by a technician using the direct-indirect method and 60 made of zirconia ceramics by CAD/CAM technology, was conducted. The inlays were cemented with two types of cementing agents-GIC (Tokuyama Ionotite F) and dual-polymerizing cement (Tokuyama Estecem kit). The unit of observation was the thickness of the cementing agent. RESULT: There was statistical significant difference (p<0.05) comparing groups, where the thickness of the fixing agent in the zirconia inlays is significantly smaller to the one in composite inlays. This applies to the dual-polymerizing cement (Tokuyama Estecem kit) as well as to GIC (Tokuyama Ionotite F). We could not find any statistically significant difference regarding fixing agent thickness neither in the group of indirect composite inlays nor in the zirconia ones (p>0.05). CONCLUSION: Both types of cements show satisfying results regarding the thickness of the fixing agent in the four examined groups.

Oral hygiene levels in primary molars restored with preformed metal crowns

“…The gingivitis may occur if the crown margins are inadequately trimmed (8,9,11,19) or when there are cement residues in contact with the gingival sulcus (17,19). The properties of the fixing agent -thickness and microleakage also affect the adaptation, the resistance, and the longevity of the restoration in the oral cavity (20). The "good" and "fair" adaptation seemed to cause minimal gingival irritation or plaque accumulation (9,10,11,13,16) The patients who are with high caries risk with severely destroyed teeth or show high rate of plaque accumulation and food residues in the gingival area are indicated for restoration with PMCs.…”