Histological of dental pulp of dogs whith the use of tetrafluoroethane

Abstract

The purpose of the present study was to evaluate the response of dog pulp tissue to exposure to the cooling agent tetrafluoroethane for ten seconds. Two 6-month-old Beagle dogs were used in the experiment. Incisors, canines and premolars of the two half arches were exposed to the cooling agent, and the contra lateral half arches were used as controls. The dogs were euthanized immediately after exposure. Their maxillas and mandibles were sectioned, and all apical thirds were removed for better fixation of the pulp tissue. The specimens were decalcified and the teeth were divided in 4 groups. Serial buccolingual sections were performed on incisors and canines at the region where the tetrafluoroethane had been applied. Premolars were sectioned mesiodistally. Light microscopy was used to evaluate the 6-mm sections, and the results were analyzed statistically (McNemar's chi-square). No statistically significant difference was found between the groups in the evaluation for the presence and conditions of the odontoblastic layer, presence of acellular and cellular zone, and presence of pulp hyperemia and inflammation. Under the conditions of the present experiment, the cooling agent tetrafluoroethane did not cause histologically detectable injury to dog pulp tissue.