Immunohistochemical and histopathological changes in the teeth of rats after lead acetate application.

Objective: To study the toxic processes of lead in teeth by investigating the histopathologic and immunohistochemical effects of lead on incisor teeth of rats.

Study design: Thirty Wistar Albino rats weighing 180-200 g were divided into 2 groups: a control group and a lead acetate group (i.e., the experimental group). The experimental group received lead acetate at 500 ppm in their drinking water for 60 days, and the control group received distilled water. The sections of the control group and the experiment group were histopathologically compared.

Results: The longitudinal cross-sections of the mandibular incisor teeth were analyzed. Degeneration in the periodontal membrane and vascular dilation in pulp and inflammatory cell infiltration were observed, and vimentin expression was seen in the dental pulp and the periodontal membrane.

Conclusion: The presence of vimentin in the dentinal tubules indicated that the odontoblast processes in these tubules were positive. In the experimental group the profile of dentinal tubules was found to be impaired and disorganized. These results indicate a loss of collagen fibers in the periodontal membrane of incisor teeth in the experimental group. In the same group the gripping function of the incisor teeth was affected due to the spacing of the intermediate filaments that are located between the alveolar bone and the periodontal ligament. The expression of vimentin on the tooth was reduced by the lead acetate treatment. Lead acetate may affect the adhesion of the tooth to the alveolar bone.