MTT versus other cell viability assays to evaluate the biocompatibility of root canal filling materials: a systematic review.

MTT and XTT do not cause over- or underestimation of cell viability during cytotoxicity screening of root canal filling materials, implying that these assays can be considered reliable for this purpose. Nonetheless, the development of protocols for the cytotoxic screening of these materials on 3D tissue-like cultures aiming to improve their predictability in the clinical scenario is suggested.