Apical Leakage of Root-End Placed SuperEBA, MTA, and Geristore Restorations in Human Teeth Previously Stored in 10% Formalin

The purpose of this study was to determine if storage of extracted teeth in 10% formalin affects microleakage of MTA, Geristore, or SuperEBA root-end fillings. There were 130 freshly extracted single-rooted teeth collected, immediately placed in phosphate buffered saline (PBS) and stored for less than 24 hours. Teeth were divided and either placed in 10% formalin for a 4-weeks immersion or immediately prepared. Preparation for all teeth consisted of canal instrumentation, obturation, apical resection, retrograde preparation, and placement of a root-end filling material. After 72 hours, the apical portions were immersed in India ink under vacuum pressure for 30 minutes, and then stored in ink for 1 week. Negative controls and positive controls performed as expected. In general, there was significantly less dye leakage of root-end restorations in teeth stored in 10% formalin when compared to the freshly extracted teeth (p < 0.0001). No difference in dye leakage was observed between Geristore restorations placed in teeth stored in formalin as compared to fresh teeth (p = 0.892). Less dye leakage was noted in teeth restored with Geristore as compared to MTA and SuperEBA, regardless of storage medium (p < 0.0001). No difference was observed between MTA and SuperEBA root-end restorations (p = 0.157). The results of this study provide evidence that storage of teeth in 10% formalin over a 4-week period may significantly influence dye leakage as compared to leakage in freshly extracted teeth.