Polymerization and cementation methods of two self-adhesive luting cements

Introduction: The aim of this study was to evaluate two different luting cements and how their clinical procedures influence post cementation quality.

Methods: Thirty-six freshly extracted mono-radicular teeth were endodontically treated and randomly divided into two groups (n=18). Posts were cemented respectively with two different self-adhesive luting cements: Group A - Relyx Unicem (3M Espe, USA) and Group B - Multilink Sprint (Ivoclar-Vivadent, Lichtestein) following manufacturer's instructionsfor positioning and handling. Teeth were then thermocycled according to protocol ISO/TR 11405 and were immersed for 24 hours in a 2% methylene-blue solution. Each tooth was sectioned by a diamond-coated saw (Isomet-Buhler, Buffalo, NY,USA) from CEJ to apex. Each slice was examined for the presence or absence of gutta-percha remnants, voids, bubbles, dye infiltration degree and polymerization grade of the luting agent. Findings were evidenced by stereoscopic microscopy (60x) and Micro-Raman spectroscopy for conversion degree of the luting agent. Mann-Whitney and ANOVA statistical analysis were performed for all results.

Results: No statistical significances were evidenced for gutta-percha presence, dye infiltration and polymerization degree. Voids were present mostly in Group B and bubbles in Group A. Both differences were statistically significant and were due two positioning and handling of the material.

Conclusions: Protocols for fibre-glass posts cementation are fundamental for the clinical success. Self adhesive luting cements, if used correctly, could be an acceptable and fast luting agent for post cementation.