Early responses of human pulp to direct capping with resin adhesive systems and calcium hydroxide.

OBJECTIVE: Early responses of human pulp to Prime&Bond/phosphoric acid, Clearfil SE Bond, Clearfil S3 Bond and Dycal were investigated ex vivo.

MATERIALS AND METHODS: The three adhesives, Dycal or buffer (DPBS) were applied directly onto the pulp of human teeth slices that were placed in culture for 4 days. Cell viability was monitored by the MTT assay during the culture period. After 4 days, tissue integrity was examined by hematoxylin-eosin staining. Vimentin levels were assessed by Western blotting. TUNEL assay was applied for apoptotic cell detection at specific pulp areas.

RESULTS: Profound reduction of cell viability and tissue integrity was observed in adhesive-treated groups, while the impact of Dycal was found to be less harmful. Extended apoptosis was caused mostly by the Clearfil SE and Prime&Bond. All adhesives reduced Vimentin levels.

SIGNIFICANCE: The study provides evidence that early pulp responses to direct capping with different adhesive systems or calcium hydroxide may vary significantly and underline the need for further studies in relevant ex vivo systems.