Effects of mineral trioxide aggregate, BiodentineTM and calcium hydroxide on viability, proliferation, migration and differentiation of stem cells from human exfoliated deciduous teeth

Abstract Objective: The aim of the study was to evaluate the effects of the capping materials mineral trioxide aggregate (MTA), calcium hydroxide (CH) and BiodentineTM (BD) on stem cells from human exfoliated deciduous teeth (SHED) in vitro. Material and Methods: SHED were cultured for 1 – 7 days in medium conditioned by incubation with MTA, BD or CH (1 mg/mL), and tested for viability (MTT assay) and proliferation (SRB assay). Also, the migration of serum-starved SHED towards conditioned media was assayed in companion plates, with 8 μm-pore-sized membranes, for 24 h. Gene expression of dentin matrix protein-1 (DMP-1) was evaluated by reverse-transcription polymerase chain reaction. Regular culture medium with 10% FBS (without conditioning) and culture medium supplemented with 20% FBS were used as controls. Results: MTA, CH and BD conditioned media maintained cell viability and allowed continuous SHED proliferation, with CH conditioned medium causing the highest positive effect on proliferation at the end of the treatment period (compared with BD and MTA) (p<0.05). In contrast, we observed increased SHED migration towards BD and MTA conditioned media (compared with CH) (p<0.05). A greater amount of DMP-1 gene was expressed in MTA group compared with the other groups from day 7 up to day 21. Conclusion: Our results show that the three capping materials are biocompatible, maintain viability and stimulate proliferation, migration and differentiation in a key dental stem cell population.

摘要
研究目的：本研究旨在体外评估三种盖髓材料——三氧化矿物凝聚体（mineral trioxide aggregate, MTA）、氢氧化钙（calcium hydroxide, CH）以及Biodentine™（BD）——对人脱落乳牙干细胞（stem cells from human exfoliated deciduous teeth, SHED）的作用。
材料与方法：将人脱落乳牙干细胞置于经MTA、BD或CH（浓度为1 mg/mL）孵育制备的条件培养基中培养1至7天，采用MTT法检测细胞活力、磺酰罗丹明B（SRB）染色法检测细胞增殖。此外，采用带有8 μm孔径膜的配套培养板，检测经血清饥饿处理的人脱落乳牙干细胞向条件培养基的迁移情况，培养时长为24小时。采用逆转录聚合酶链反应检测牙本质基质蛋白1（dentin matrix protein-1, DMP-1）的基因表达水平。设置两组对照组：含10%胎牛血清（fetal bovine serum, FBS）的常规未条件化培养基，以及添加20%胎牛血清的培养基。
结果：MTA、CH及BD的条件培养基可维持细胞活力，并支持人脱落乳牙干细胞持续增殖；其中CH条件培养基在培养周期结束时对增殖的促进效果最为显著（相较于BD与MTA组，p<0.05）。与之相反，相较于CH组，BD与MTA的条件培养基可促进人脱落乳牙干细胞的迁移（p<0.05）。自第7天至第21天，MTA组的DMP-1基因表达量均高于其余各组。
结论：本研究结果表明，三种盖髓材料均具有生物相容性，可维持人脱落乳牙干细胞的活力，并可促进该关键牙髓干细胞群体的增殖、迁移与分化。