Microleakage of temporary endodontic restorations in teeth restored with amalgam

Microleakage of seven temporary restorative materials was evaluated in endodontic access preparations made in teeth restored with amalgam. Ten teeth were used for each of the seven materials: Cavit, Cavit-G, TERM, zinc phosphate cement, polycarboxylate cement, glass ionomer cement, and IRM. A class I amalgam was placed in the occlusal surface of each experimental tooth and an endodontic access preparation was made entirely within the amalgam. Then the access preparation was restored with one of the temporary restorative materials, and microleakage was evaluated using a fluid filtration technique. The amount of microleakage was quantitated by measuring the fluid flow at 15 min, 1 h, 24 h, 1 wk, and 2 wk after insertion of the temporary restoration. Cavit, Cavit-G, TERM, IRM, and glass ionomer cement all provided excellent seals while zinc phosphate cement and polycarboxylate cement provided less effective seals.