Immunohistochemical localization of metallothionein in dental pulp after cavity preparation of rat molars

ObjectiveMetallothionein (MT) is an intracellular cysteine-rich protein associated with cell proliferation and differentiation. Our objective was to examine immunohistochemically the localization of MT in the rat dental pulp after cavity preparation.Study designCavities were prepared on the upper first molars of 9 rats. Specimens were collected at 1, 3, and 5 days after cavity preparation, and paraffin sections were made. For double-immunohistochemical staining, anti-MT monoclonal antibody (E9) and anti–proliferating cell nuclear antigen (PCNA) monoclonal antibody (PC10) were applied.ResultsAt 3 days after cavity preparation, some odontoblasts corresponding to the cavity, many pulp cells, and some endothelial cells in the pulp under the cavity showed both MT- and PCNA-positive immunostainings.ConclusionMetallothionein was detected in the dental pulp after pulp injury, and it is likely that MT is closely related to the proliferation of newly differentiating odontoblasts and angiogenesis during the healing process.