EVALUATION OF BULK, PRE-POLYMERIZED RESIN BALL OR b -QUARTZ INSERT RESTORATIVE TECHNIQUES ON MICROLEAKAGE
Polymerization shrinkage of composite resin at the margin of a restoration can have deleterious effects on its longevity. The purpose of this study was to examine the effect of three direct composite resin restorative techniques, two of which involve the concept of inserts, on microleakage. Thirty extracted human third molars had class V cavity preparations placed with the occlusal margins in enamel and the gingival margins in dentin. Enamel margins were etched and Syntac® dentin bonding system was applied to the preparations. Teeth were randomly restored with Heliomolar® composite resin using three techniques(n=20): composite alone using a bulk technique; composite with a Beta-quartz insert, and; composite with a prepolymerized composite ball insert. Samples were thermocycled 1,000 times between 5o and 55o C, stained with 0.5% basic fuchsin dye, sectioned and scored for dye penetration. Data was analyzed using a Kruskal Wallis and Mann-Whitney U tests at a significance level of p < 0.05. The prepolymerized composite ball group had significantly more microleakage than the Beta-quartz insert or bulk technique groups. From the results of this study, the extra time required to use the megafilled insert techniques provide no advantage with regards to microleakage using Heliomolar® composite and Syntac® dentin bonding system.