Isfahan University of Medical SciencesDental Research Journal1735-33271220080113The Role of Pretreatment of Primary Teeth Dentin with Phosphoric and Polyacrylic Acid on Shear Bond Strength of a R-MGI and a Compomer1212AbbasMakarem. drj@dnt.mui.ac.irBehjat AI-MolookAjamiMasumehEbrahimi20101106Introduction The purpose of this study is to compare and determine the role of H3P04 and polyacrylic acid in shear bond strength of Fuji II LC and Compoglass on dentin of primary teeth. Method & Materials 90 sound primary molars were selected. Enamel reduction was done until smooth dentinal occlusal surface was achieved. The teeth then were randomly divided into six groups. A plastic mold was prepared and selected material was applied in half of the mold and light cured. The samples were stored in an incubator. Then the samples were thermo cycled. The shear bond strength was determined with an Instron Machine. Results The results showed a significant difference in mean shear bond strength for Compoglass between etched and unetched dentin (P Value=O.00