[Effects of mineral trioxide aggregate on the proliferation and differentiation of human pulp cells from primary and permanent teeth].

ABSTRACT

OBJECTIVE: This study aims to investigate the effects of mineral trioxide aggregate (MTA) and calcium hydroxide on proliferation and differentiation of human pulp cells from primary and permanent teeth. METHODS: Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) assay. The mRNA expression levels of dentinogenesis-related factors, including alkaline phosphatase (ALP) and dentin sialophosphoprotein (DSPP), and odontoclastogenesis-related factors, such as osteo- protegerin (OPG) and receptor activator of NF-κB ligand (RANKL), were determined by real time polymerase chain reac- tion (PCR). RESULTS: Primary and permanent pulp cells treated with calcium hydroxide exhibited significantly lower proli- feration rates than the control cells (P<0.01). By contrast, the MTA-treated group showed significantly higher proliferation rates than the control group (P<0.01). Real time PCR results showed that calcium hydroxide-treated primary pulp cells exhi- bited significantly decreased ALP, DSPP, and OPG expression compared with the control group (P<0.01). Conversely, the MTA-treated group displayed significantly increased ALP, DSPP, and OPG expression (P<0.01). Calcium hydroxide-treated primary pulp cells also exhibited significantly upregulated RANKL expression (P < 0.01); by contrast, MTA-treated cells did not show any change in RANKL expression (P>0.05). Likewise, MTA-treated permanent pulp cells showed significantly upregulated ALP and DSPP expression (P < 0.01). However, the calcium hydroxide-treated group remained almost the same as the control group (P > 0.05). Neither MTA nor calcium hydroxide affected OPG and RANKL expression in per- manent pulp cells (P > 0.05). CONCLUSION: MTA is more suitable as a pulp-capping agent, particularly in primary teeth, than calcium hydroxide.