Various additives have been suggested to be used with MTA to improve its handling characteristics. The objective of this study was to evaluate the effects of various additives on cytotoxicity of MTA. Division of Endodontology, School of Dental Medicine, The University of Connecticut Health Center, Farmington, CT 06030-1715, USA. RESULTS: Source Abstract Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2009 May;107(5):739-44. Jafarnia B, Jiang J, He J, Wang YH, Safavi KE, Zhu Q.