三氧化矿物凝聚体对人乳牙牙髓细胞增殖和分化影响的实验研究

目的 对比三氧化矿物凝聚体(mineral trioxide aggregate,MTA)和氢氧化钙对人乳牙牙髓细胞增殖和分化的影响,为MTA应用于乳牙活髓保存治疗提供实验依据.方法 培养原代人乳牙牙髓细胞,采用噻唑蓝比色法检测乳牙牙髓细胞生长增殖的变化;von Kossa染色观察牙髓细胞钙结节形成情况,并计数分析;使用实时荧光定量聚合酶链反应法检测碱性磷酸酶(alkaline phosphatase,ALP)、牙本质涎磷蛋白(dentin sialophosphoprotein,DSPP)基因的表达.结果 氢氧化钙组牙髓细胞增殖率显著低于对照组和MTA组(F=1792.301,P<0.01),最大增殖率为89.7%;MTA组牙髓细胞增殖率显著高于氢氧化钙组和对照组(F=1835.065,P<0.01),最大增殖率为118.4%.氢氧化钙组和MTA组牙髓细胞von Kossa染色均呈阳性,两组间钙结节计数分析差异无统计学意义(P>0.05).三组间ALP基因表达量差异有统计学意义(F=349.651,P<0.01),氢氧化钙组显著低于对照组和MTA组,MTA组显著高于氢氧化钙组和对照组;三组间DSPP基因表达量差异也有统计学意义(F=1653.001,P<0.01),氢氧化钙组显著低于对照组和MTA组,MTA组显著高于氢氧化钙组和对照组.结论 从促进乳牙牙髓细胞的增殖和分化来看,MTA比氢氧化钙更适合作为乳牙的盖髓剂.     

三氧化矿物凝聚体对成人牙髓干细胞增殖和分化的影响

目的:研究不同浓度的三氧化矿物凝聚体(mineral trioxide aggregate,MTA)对成人牙髓干细胞(human dental pulp stem cells,hDPSCs)增殖和分化的影响。方法:体外培养hDPSCs,分别以不同浓度MTA浸提液作用于hDPSCs。采用四甲基偶氮噻唑蓝(methyl thiazoly tetrazolium,MTT)法测定MTA对hDPSCs增殖的影响;Von Kossa染色法检测hDPSCs钙化结节的形成;通过酶标仪法检测hDPSCs碱性磷酸酶(alkalinephosphatase,ALP)的活性;运用逆转录聚合酶链反应(RT-PCR)法检测牙本质涎磷蛋白(dentin sialophosphopro-tein,DSPP)基因的表达。采用单因素方差分析对数据进行统计学分析。结果:2 mg/mL MTA能促进hDPSCs增殖,其ALP活性也明显高于其他各组,并可见Von Kossa染色呈阳性,有钙化结节形成,且能明显促进牙髓干细胞表达DSPP;而20 mg/mL MTA则抑制hDPSCs的增殖,ALP活性明显低于其他各组,Von Kossa染色阴性;而0.2 mg/mL MTA组及氢氧化钙组未能表现出明显的增殖分化活性。结论:2 mg/mL MTA能促进hDPSCs的增殖,并能诱导hDPSCs向成牙本质细胞方向分化。20 mg/mL MTA抑制hDPSCs的增殖,并且抑制hDPSCs向成牙本质细胞方向分化。     

三氧化矿物凝聚体(MTA)的研究进展

一种新型生物材料，三氰化矿物凝聚体(Mineral trioxide aggregate MTA)，广泛应用于牙科治疗中的直接盖髓、活髓切断、根尖成形、髓室底穿孔及根管侧穿修补、根管倒充填等多个领域。体外和体内试验证实，MTA具有良好的生物相容性，可有效促进硬组织的再生，并且具有一定的抗菌和抑菌性,对组织无毒其持久的封闭性大大提高了侧穿修补和根尖倒充填的成功功率、MTA可通过调节细胞因子的分泌，激活细胞外信号调节性激酶活性和促进骨钙素的表达等途径，影响骨的吸收和改建，进而促促进病变的愈合.虽然MTA也有其局限性，但仍是一种极具潜力的牙科新型材料。     

三氧化矿物凝聚体的性能及其研究进展

三氧化矿物凝聚体(mineral trioxide aggregate,MTA)是目前牙髓根尖周疾病诊治中采用的一种新式材料。其优良的生物学性能、材料学性能自被人们认识以来便备受推崇,逐步发展为当下口腔常见疾病的治疗中不可或缺的一员。现将其具备的性能及相关研究做一综合论述。     

三氧化矿物凝聚体临床应用的护理

近年来,一种用于牙髓病治疗的新型生物材料,三氧化矿物凝聚体（mineral trioxyde aggregate,MTA）开始用于临床.经国内外大量的研究和临床应用证明，MTA具有良好的生物相容性和封闭性，可有效促进软硬组织的再生，并且具有一定的抗菌和抑菌性，对组织无毒。笔者现将在根尖诱导成形、髓室底穿孔及根管侧穿修补等治疗过程中应用MTA的护理体会介绍如下。     

三氧化矿物凝聚体对乳、恒牙牙髓细胞增殖和分化影响的比较

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。     

三氧化矿物凝聚体修补根管穿孔的临床疗效观察

目的 观察采用三氧化矿物凝聚体（MTA）修补根管穿孔的短期临床效果。方法对2003年1月至2004年1月于我科进行根管穿孔修补的10例病例，进行定期回访，观察治疗效果。结果 复诊时10例患者均无不适主诉。修补前后X线片对照显示，7例修补前穿孔周围无病变的病例复查时无新发病变。3例术前病变面积较大的病例复查时，其中2例病变完全愈合，1例明显缩小。除1例左上第二磨牙腭根远中侧穿的患牙在远中探及7mm的牙周袋外，其余均无4mm以上的牙周袋。结论 MTA是目前临床上较理想的根管穿孔的修补材料，能够最大限度的保存患牙，短期临床疗效好，长期效果有待于进一步观察。     

三氧化矿物凝聚体用于修补髓腔穿孔的临床效果观察

目的 研究三氧化矿物凝聚体(mineral trioxide aggregate,MTA)修补髓腔穿孔的临床效果.方法 收集临床髓室底或髓室、根管侧壁穿孔的恒牙8颗,用MTA对穿孔处填塞、修补.完成根管充填及永久充填后定期复查.追踪观察0.5～5.0年.结果 经复查8颗患牙无临床不适症状,咀嚼功能正常,X线片显示穿孔处未见新的牙槽骨病变,或原有牙槽骨病变缩小.结论 MTA是一种较理想的髓腔穿孔修补材料.     

三氧化矿物凝聚体在显微根尖术治疗难治性慢性根尖周炎中的应用研究

目的 探究显微根尖手术（Dental operating microscope,DOM）治疗难治性慢性根尖周炎时应用三氧化矿物凝聚体的可行性。方法 选择2016年2月~2017年2月在扬州友好医院口腔科就诊的难治性慢性根尖周炎89例（89颗患牙,每人1颗患牙）患者,行DOM同时应用三氧化矿物凝聚体（Mineral Trioxide Aggregate,MTA）作为倒填充材料,术后3个月、半年、一年定期随访复查,以临床检查和影像学检查评价患者根尖周病损的愈合情况,其中临床检查以患者主诉疼痛和视诊、扪诊及咬诊对患牙进行判断,并根据影像学及临床检查分为治愈、改善和失败3个等级,评价临床治疗效果,同时分析性别、年龄、患牙牙位分布对治疗效果的影响。结果 1年后随访复查结果显示治疗成功率达95.51%,性别、年龄及患牙牙位分布均未对DOM治疗效果产生明显影响,4例治疗失败患者中1例磨牙因根折被拔除,2例前牙因根折或重度牙周炎症造成术后再次出现瘘管,1例因牙周袋较深被拔除。结论 DOM治疗难治性慢性根炎周炎时应用MTA封闭技术是一种较为可靠有效的方法,值得在临床推广使用。     

三氧化矿物凝聚体修补医源性根管穿孔的疗效分析

目的 评价三氧化矿物凝聚体(mineral trioxide aggregate,MTA)修补根管医源性穿孔的临床效果.方法 选取根管医源性穿孔病例21例,预备根管、彻底清理穿孔区,根管显微镜下以MTA修补根管穿孔,完成充填.定期回访,收集患者术前、修补后即刻和术后复查的X线片,根据临床检查和X线片检查评价结果.结果 复诊时21例中除2例为有效(存在密度减低影但较术前明显缩小)外,其余19例均为愈合(无密度减低影),无失败病例.结论 MTA治疗医源性穿孔的临床疗效较好.

Abstract：

Objective To observe the clinical effect of iatrogenic perforation repaired by mineral trioxide aggregate(MTA). Methods Twenty-one iatrogenic perforation cases were included. The root canals were shaped and cleaned and then obturated after MTA was used to repair the perforation with microscopes.Preoperative, immediate postoperative, and follow-up radiographs were evaluated to determine the pathologic changes adjacent to the perforation site. Results Nineteen cases healed and two cases were healing. No cases failed. Conclusions MTA is effective in the treatment of iatrogenic perforation.     

Effect of mineral trioxide aggregate on proliferation of cultured human dental pulp cells

AIM: To investigate the effect of mineral trioxide aggregate (MTA) on the proliferation of human dental pulp (HDP) cells ex-vivo. METHODOLOGY: Human dental pulp cells were cultured with MTA or calcium hydroxide-containing cement (Dycal) using culture plate inserts. Control cells were cultured with culture plate inserts only. Cell proliferation was measured for up to 14 days using a Cell Counting kit, and the concentration of calcium ions released from the tested materials was assessed using a Calcium E-test kit. To confirm that the effect of MTA was attributable to released calcium ions, cell proliferation was measured in the presence of exogenous calcium chloride as a source of calcium ions while in the absence of MTA. RESULTS: Mineral trioxide aggregate significantly stimulated cell proliferation after 12 days, whereas Dycal had no such effect. The number of calcium ions released from MTA was significantly higher than that released from Dycal. Following the addition of calcium chloride, cell proliferation increased in a dose-dependent manner after 12 days. Moreover, cell proliferation showed a similar pattern whether a given concentration of calcium ions was produced by calcium chloride or by release from MTA. CONCLUSIONS: In this ex-vivo study, the elution components such as calcium ions from MTA had higher proliferation ability of HDP cells than control and Dycal.     

Direct contact with mineral trioxide aggregate activates and differentiates human dental pulp cells

Introduction

Mineral trioxide aggregate (MTA) is routinely used for pulp-capping procedures. However, little is known about its direct interaction with the cells or whether MTA is capable of releasing soluble factors that could help in differentiating cells. There have been no previous studies showing this aspect of MTA. Hence, the aim of this study was to determine whether direct contact of the cells with MTA was necessary to help differentiate the pulp cells into odontoblast-like cells.

Methods

Human dental pulp cells were cultured on gray MTA, either in direct contact or away from the cells on a cell culture insert, and the levels of gene expression, secretion of vascular endothelial growth factor (VEGF), and the rates of cell proliferation were analyzed.

Results

MTA when placed in direct contact with the cells promoted up-regulated the expression of important odontoblastic genes like osteocalcin and dentin sialoprotein, thereby showing that direct contact of the cells with the MTA is necessary to promote differentiation of the pulp cells into odontoblast-like cells, which in turn are responsible for dentin bridge formation. MTA also induced an increase in the secretion of VEGF when placed in direct contact with the cells.

Conclusions

Overall, our study supports the fact that direct contact of the cells with the MTA is necessary to help differentiate them into odontoblast-like cells, which in turn will lead to a successful treatment outcome.     

Effect of N-acetylcysteine on rat dental pulp cells cultured on mineral trioxide aggregate

Introduction

The purpose of this study was to evaluate the cytotoxicity of mineral trioxide aggregate (MTA) and its potential detoxification by an antioxidant amino acid, N-acetylcysteine (NAC).

Methods

Rat dental pulp cells extracted from rat maxillary incisors were directly cultured on MTA with or without NAC in culture me-dium. The number of cells and their spreading behavior were both assessed 24 hours after seeding. The intracellular levels of reactive oxygen species (ROS) and glutathione (GSH) were also assessed after 24 hours of culture.

Results

The number of cells attached to MTA was 60% greater when NAC was added to the culture medium. In addition, the area and perimeter of the cells were found to be 2-fold greater in the culture containing NAC. Cells cultured on MTA alone showed large ROS concentrations, which disappeared when the medium was supplemented with NAC. The intracellular GSH level, however, increased 3.5-fold with NAC addition.

Conclusions

This study demonstrated that the presence of NAC in environments can substantially improve attachment and spreading behaviors of dental pulp cells on MTA. This biological effect was associated with an im-provement in the cellular redox system by NAC and warrants further exploration of NAC for determining its therapeutic value in improving the biocompatibility of MTA.     

Revascularization versus apical barrier technique with mineral trioxide aggregate plug: A systematic review

Aim

To compare the clinical and radiographic outcomes observed in Necrotic Immature Permanent Teeth (NIPT) after revascularization or apexification with MTA-apical plug.

Survey on the teaching and use of mineral trioxide aggregate in UK dental schools

The aim was to find out whether undergraduate students in UK dental schools were taught about and used clinically Mineral Trioxide Aggregate (MTA). The census point was the end of October 2005 when a total of 220 papers were cited on PubMed. A questionnaire was sent to 13 schools, all of which responded. Three schools had dedicated units, or departments, of endodontology. The endodontic staff in every school used MTA in clinical practice. In all 13 schools undergraduate students were taught about the clinical use of MTA in endodontics, but in only nine schools were they taught about its use in paediatric dentistry. In none of the 13 schools did students have the opportunity to use MTA in preclinical exercises. The opportunity for some students to observe the use of MTA in specific procedures varied according to the procedure. Students in seven schools had the opportunity to observe pulp capping with MTA, as well as its use in immature roots, in nine schools to observe use of MTA in surgical endodontics, and in 12 schools to observe perforation repair. The opportunity for students to use MTA in specific procedures varied according to the procedure, and was less than that for observation. The material routinely used by students varied according to the procedure; in five schools the routine material for root-end surgery was MTA, otherwise students largely used traditional materials. Despite there being 220 papers on MTA over a 10-year period the introduction of its clinical use in the undergraduate curriculum was limited.     

MTA形成根尖屏障的疗效观察

目的:评价在手术显微镜下采用无机三氧化聚合物(mineraltrioxideaggregate,MTA)形成根尖屏障、治疗根尖孔未闭合患牙的临床疗效。方法:选取根尖孔未闭合的患牙23颗,完成根管预备后,在手术显微镜下将MTA充填于根尖1/3段,形成3～5㎜的根尖屏障,硬固后完成根管中、上段的充填及冠部修复,观察疗效。结果:所有病例在2～3周内完成根管充填,术后X线片显示16颗患牙适充,7颗超充约1～2㎜,根充致密;除失访及不能亲自前来复诊检查的患者外,其余19颗均达到成功要求,患牙无不适,瘘管闭合,无叩痛;复查X线片示根尖周病变明显缩小或消失,无新的暗影出现。结论:MTA治疗根尖孔未闭合的患牙治疗周期短,临床疗效好,少量超充不影响疗效。     

Hydration mechanisms of mineral trioxide aggregate

AIM: To report the hydration mechanism of white mineral trioxide aggregate (White MTA, Dentsply, Tulsa Dental Products, Tulsa, OK, USA). METHODOLOGY: The chemical constitution of white MTA was studied by viewing the powder in polished sections under the scanning electron microscope (SEM). The hydration of both white MTA and white Portland cement (PC) was studied by characterizing cement hydrates viewed under the SEM, plotting atomic ratios, performing quantitative energy dispersive analyses with X-ray (EDAX) and by calculation of the amount of anhydrous clinker minerals using the Bogue calculation. RESULTS: Un-hydrated MTA was composed of impure tri-calcium and di-calcium silicate and bismuth oxide. The aluminate phase was scarce. On hydration the white PC produced a dense structure made up of calcium silicate hydrate, calcium hydroxide, monosulphate and ettringite as the main hydration products. The un-reacted cement grain was coated with a layer of hydrated cement. In contrast MTA produced a porous structure on hydration. Levels of ettringite and monosulphate were low. Bismuth oxide was present as un-reacted powder but also incorporated with the calcium silicate hydrate. CONCLUSIONS: White MTA was deficient in alumina suggesting that the material was not prepared in a rotary kiln. On hydration this affected the production of ettringite and monosulphate usually formed on hydration of PC. The bismuth affected the hydration mechanism of MTA; it formed part of the structure of C-S-H and also affected the precipitation of calcium hydroxide in the hydrated paste. The microstructure of hydrated MTA would likely be weaker when compared with that of PC.