Effect of Strontium Substituted Tetracalcium Phosphate Cement on Proliferation and Mineralization Potential in Human Dental Pulp Stem Cells

OBJECTIVE: The aim of this study was to comparatively evaluate the proliferation, differentiation and mineralization inducing potential of strontium incorporated tetracalcium phosphate cement (STTCP) and mineral trioxide aggregate (MTA) on human dental pulp stem cells (hDPSCs). METHODS: hDPSCs were cultured from freshly extracted human premolar teeth. Cement discs (5mm×3mm) were prepared using MTA and STTCP. hDPSCs were exposed to the test materials and grouped as follows: 1. MTA; 2. STTCP; 3. NC: Media alone (negative control; 4.PC: hDPSCs with osteogenic medium (positive control); Cell viability and proliferation was evaluated using MTT and trypan blue assays for 0, 7 and 14 day intervals. Odontoblastic differentiation potential were evaluated using ALP assay followed by degree of mineralization using Alizarin Red test and Osteopontin expression on day 7,14 and 21. Quantitative analysis were done by evaluating the absorbance and expressed as optical density. Statistical analysis was performed using Kruskal Wallis test followed by Friedman test (P<0.05). RESULTS: MTA showed higher percentage of cell proliferation than STTCP at day 7 and 14. ALP assay revealed higher significant value for STTCP on day 7 and 14. STTCP exhibited intense staining and similar mineralization potential with MTA at all time periods. Osteopontin expression was exhibited by both MTA and STTCP on all days (P<0.05). CONCLUSION: STTCP promoted cell viability and enhanced mineralization and odontogenic differentiation potential on hDPSCs similar to MTA. STTCP has a potential to be an alternative therapeutic agent for pulp capping procedures.