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.
目的: 对比三氧化矿物凝聚体（MTA）和氢氧化钙对人乳、恒牙牙髓细胞增殖和分化的影响。
方法: 采用甲基噻唑基四唑（MTT）法检测牙髓细胞生长增殖变化；实时荧光定量聚合酶链反应（PCR）检测碱性磷酸酶（ALP）、牙本质涎磷蛋白（DSPP）、骨保护因子（OPG）、核因子κB受体活化因子配体（RANKL）基因的表达。
结果: 氢氧化钙组乳、恒牙牙髓细胞增殖均显著低于对照组（P<0.01），MTA组乳、恒牙牙髓细胞增殖均高于对照组（P<0.01）。实时荧光定量PCR检测结果显示，乳牙氢氧化钙组ALP、DSPP和OPG的表达显著低于对照组（P<0.01），MTA组上述因子的表达显著高于对照组（P<0.01）；氢氧化钙组RANKL的表达显著高于对照组（P<0.01），MTA组RANKL的表达与对照组差异无统计学意义（P>0.05）。恒牙牙髓细胞氢氧化钙组ALP和DSPP的表达与对照组相比无显著差异（P>0.05），MTA组ALP和DSPP的表达显著增加（P<0.01）；氢氧化钙组和MTA组OPG、RANKL的表达与对照组无显著差异（P>0.05）。
结论: MTA比氢氧化钙更适合做乳牙和恒牙的盖髓剂，其优势在乳牙可能更为明显。