Analysis of microleakage for two adhesive systems with different adhesive strategies

Abstract

Aim. The purpose of this in vitro study was to evaluate microleakage of two different adhesive systems: self-etch and etch-and-rinse, using the optic microscopy. Materials and methods. Six sound upper premolar teeth had MOD cavities prepared. The teeth were divided into two groups of three teeth each and two restorative systems were used: 1) Filtek™ Silorane/Silorane System Adhesive (3M ESPE); 2) Premise™ Packable /OptiBond FL (KERR). All restorative materials were placed following manufacturers’ recommendations. After restoring them, the teeth were stored for 5 years in an oven in distilled water at 37°C. Before the tests, the apex was sealed with wax and the teeth were covered with nail polish except 1 mm around the edge restorations. Then, they were immersed in 0.5% alkaline solution of fuchsin for 24 hours. After sectioning, the microleakage evaluation at enamel margin was made using an optical microscope Olympus KCX41 (Olympus America Inc.) at a magnification of 4x and 10x, the method of granting a semiquantitative score of dye penetration on a scale from 0-3. Data were statistically analyzed using Kruskal-Wallis test. Results, conclusions. Microleakage was present in both groups, scores 2 (infiltration dye the entire length threshold cervical enamel) and 3 (infiltration threshold cervical enamel and expanding axial wall towards the pulp chamber), registering only in the Filtek Silorane (FS) group who applied to Silorane system, adhesive Self-etch adhesive system. The most effective adhesive system to reduce the microleakage at marginal threshold cervical MOD restorations on enamel, was etch-and-rinse system, OptiBond FL.