The purpose of this study was to determine the effects of new adhesive bonding agents on the pulp and surface topography of etched enamel in rat teeth. In this study, 240 molar teeth of 20 Wistar Albino rats were used. Teeth were divided into five groups: Group I, ultra etch was applied for 15 seconds. Group II, ultra etch was applied for 30 seconds, Group III, ultra etch and bonding primer were applied for 15 seconds, Group IV, ultra etch and bonding primer were applied for 30 seconds. Group V (control group), 40 molar teeth without any procedure were selected. Each group, had 50 rat molar teeth, were divided into two subgroups. Twenty-five teeth were evaluated 24 hours later, the other twenty-five teeth were evaluated 7 days later. In addition, each subgroup was divided into two groups: 12 teeth prepared for investigation with scanning electron microscope (SEM) and 13 teeth prepared for investigation with light microscope. In conclusion, in order to prevent the destruction of etching on enamel, we recommend etching the enamel for 15 seconds.