Sealing quality of polycarboxylate cements when compared to amalgam as retrofilling material.

Four hundred roots were uniformly prepared for retrofilling. One hundred of these were retrofilled with amalgam and served as controls for the study. The polycarboxylate cements--Durelon, PCA, and Poly C--were each used as retro-filling material for 100 roots. After immersion in 2 per cent aqueous methylene blue for 7 days, the roots were sectioned in 1 to 2 mm. increments to determine the depth of dye penetration. The depth of dye penetration was used as a measure of their sealing effectiveness. The groups were compared statistically by means of a t test. All cements were significantly different from amalgam. All cements performed inferiorly to amalgam, an already accepted retrofilling material.