The aim of the current study was to evaluate the impact of a new silicate-based capping material on healing potential of traumatically exposed healthy dog's dental pulp.
Materials and Methods: Two pulp capping materials were evaluated in this study; Mineral trioxide aggregate (MTA), and Five mineral oxides (5MO). Glass ionomer as overlying restorative material. Six adult healthy dogs with intact permanent dentition were selected for the study. A total of sixteen anterior teeth were used in each dog. Both pulp capping materials were used in the same dog. Class V cavities were prepared on the teeth. After pulp exposure, the pulp capping materials were applied directly to the exposed pulp. All cavities were sealed with glass ionomer restorative material. The used six dogs were divided into two groups; three dogs each, according to the capping periods to 7 days and 90 days. At the end of each period the dogs were sacrificed by injecting an overdose of pentobarbital sodium. Teeth were separated from bone with immediate sectioning of their roots in the mid-way between cementoenamel junction and apex. The teeth were fixed in 10% neutral buffered formalin. Then the teeth were demineralized in Morse's solution (50% formic acid and 20% sodium citrate) for 3 months. In the last, the teeth were embedded in paraffin wax and serially sectioned buccolingually and stained with hematoxylin-eosin. The specimens were examined under optical light microscope to estimate the amount of pulp inflammation and dentin bridge formation at the interface of the capping materia