Abrasion of microfill restorative resins in Class 1 cavities

Abrasion of Class 1 microfill restorations has been studied over a period 2 years. The materials used were the commercial products Isomolar (Ivoclar, Liechtenstein) and Silar (3 M Co., U.S.A.). All fillings were placed in permanent mandibular first molars of Copenhagen schoolchildren. The abrasion for Isomolar (29 fillings) was found to be 9.8 +/- 10.3 (range -9 to 28) micrometers per year, and for Silar (27 fillings) 11.8 +/- 13.0 (range -5 to 41) micrometers per year. Statistically no difference could be demonstrated between the two products.