This study evaluated the biocompatibility and ability to induce mineralization of tristrontium aluminate (S3A) cement, a proposed alternative to mineral trioxide aggregate (MTA) for endodontic applications. Mouse dental pulp stem cells were cultured with extracts of S3A cement or MTA cement. The S3A cement extract did not inhibit cell proliferation or attachment compared to the control. Both S3A and MTA cement extracts induced mineralized nodule formation and expression of odontoblastic/osteogenic marker genes, with MTA showing a higher level of cell proliferation than S3A at 3 days. The results suggest S3A cement has biocompatibility and pro-min