Management of immature teeth with apical infections using mineral trioxide aggregate

Traumatic injuries to the young permanent teeth lead to devitalization of the pulp with concomitant arrest in further development of the immature root of the involved tooth. Hermetic seal of the root canal system during obturation is not possible in such cases, due to the lack of an apical constriction. The traditional management technique in such cases has been apexification involving induction of a calcific barrier at the apex using calcium hydroxide, which in turn facilitates obturation of the root canal. However this becomes complicated when there is persistent infection leading to periapical changes. This case report describes the use of mineral trioxide aggregate (MTA) for management of a periapically compromised immature tooth.     

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。     

Endodontic treatment of dens in dente associated with a chronic periapical lesion using an apical plug of mineral trioxide aggregate.

Dens in dente is a developmental anomaly that predisposes the tooth to develop caries and pulp periapical pathologies. A chronic lesion can develop without any clinical symptoms of the pathology. The purpose of this case report is to describe the endodontic treatment of dens in dente associated with a periapical lesion using a mineral trioxide aggregate apical plug.     

根管显微镜下三氧化物多聚体封闭根端的疗效观察

目的：评价根管显微镜下三氧化物聚合体（mineral trioxide aggregate,MTA）封闭恒牙根尖孔开放形成根尖屏障的疗效。方法：选择恒牙根尖孔开放合并根尖周炎的患牙63颗,在根管显微镜下用三氧化物多聚体（MTA）严密封闭根端,形成根尖屏障后以热牙胶充填,定期复诊观察。结果：63颗患牙中,1颗（23）因牙根长及舌向倾斜,在显微镜下视野不清导致欠填,其余62颗患牙均充填严密。术后X线片显示43颗适充,17颗少量超充。3个月后复查,2例因瘘管反复不闭合行手术倒充填,2例失访,其余患牙均达到成功要求,无叩痛,复查X线片示根尖周病变明显缩小或消失,骨小梁再现。少量超填不影响疗效,总成功率为95%。结论：牙科手术显微镜下MTA封闭治疗根尖孔开放的恒牙疗效确切,准确方便。     

MTA应用于穿孔修补和根尖屏障的临床效果观察

目的:临床观察MTA(mineraltrioxideaggregate)用于根尖屏障术和根管或髓室穿孔修补的治疗效果。方法:收集临床上使用MTA治疗的病例11例,其中无髓恒牙根尖孔敞开病例7例( 7个患牙)行MTA根尖屏障术,在手术显微镜下完成MTA根尖屏障的制备,垂直加压充填根管。治疗过程仅需1 ~2次复诊。使用MTA进行根管或髓室穿孔修补病例4例共5个患牙。11例观察期0. 5 ~4年多不等。结果:经追踪观察, 11例患牙在临床症状的控制和获得骨愈合方面都有良好的效果。结论:本研究结果提示,MTA对穿孔修补和根尖屏障术方面是一种满意的材料。     

Fracture resistance and histological findings of immature teeth treated with mineral trioxide aggregate

Abstract – The objective of the present study was to test the hypothesis that the fracture strength of calcium hydroxide and mineral trioxide aggregate (MTA)‐filled immature teeth decreased over time. Immature mandibular incisors from sheep were extracted and the pulps were extirpated using an apical approach with a barbed broach, and the teeth were divided into three experimental groups. Group 1: untreated teeth. Group 2: the root canals were filled with calcium hydroxide paste. Group 3: the root canals were filled with MTA. All specimens were kept in saline with 1% antibiotics at 4°C for certain periods of time: 2 weeks, 2 months, and 1 year. Then they were tested for fracture strength in an Instron testing machine. The results were subjected to statistical analysis by the Tukey–Kramer tests. A P‐value (<0.05) was considered statistically significant. One tooth from each group was selected randomly for a histological study, examining matrix metalloproteinases (MMP2 and MMP14) and tissue inhibitor of metalloproteinase (TIMP). The results showed the mean fracture strengths decreased over time for all the three groups. Although the untreated teeth showed the highest value (45.5 MPa) at 2 weeks, the fracture strengths decreased significantly after 2 months (P < 0.05). On the other hand, the teeth treated with calcium hydroxide or MTA decreased, but not significantly over time (P > 0.05). For the MTA‐treated teeth, the fracture strengths were not found significantly different from the untreated or calcium hydroxide‐treated teeth at 2 weeks or 2 months (P > 0.05). However, the strength was significantly higher in the MTA group compared with the other two groups after 1 year (P < 0.05). Immunofluorescence images revealed expression of collagen type 1, MMP‐2 and MMP‐14 in both untreated and endodontically treated teeth. However, TIMP‐2 was only observed in the MTA‐treated teeth. In conclusion, the teeth with root treatment with MTA showed the highest fracture resistance at 1 year (P < 0.05). An explanation could be that MTA induced the expression of TIMP‐2 in the dentin matrix and thereby possibly prevented destruction of the collagen matrix.     

In-vitro evaluation of microleakage of an orthograde apical plug of mineral trioxide aggregate in permanent teeth with simulated immature apices

This in vitro study evaluated the seal created by varying depths of mineral trioxide aggregate (MTA) plugs placed in an orthograde fashion in five groups of 10 teeth. One group received a 2 mm thick orthograde apical plug of MTA, the second group a 5 mm apical MTA plug, and the third group a 2 mm apical MTA plug with a second 2 mm increment, 24 h later. The remaining portion of the canal in these groups was left unfilled. Group four received a 2 mm MTA plug that set for 24 h and the canal was then back-filled with gutta-percha and eugenol based sealer. Group five was a positive control without an MTA plug. The apical seal was tested using a bacterial leakage model of Actinomyces viscosus. Results showed a statistically significant difference in only the 5 mm apical plug, which completely prevented bacterial leakage.     

应用MTA封闭根尖和修补根管侧穿的临床疗效观察

目的:观察MTA(mineral trioxide aggregate)治疗根尖敞开和根管侧穿患牙的临床疗效.方法:病例选择于解放军第306医院牙体牙髓科门诊患者共计23 例,其中根尖部敞开7 例、根管内吸收、根折造成根管侧穿6 例、医源性根管侧穿10 例.病程0.5～24 个月, X线片显示23 例均有根部或根尖周透射影.常规根管清理消毒、封药,于根管显微镜下采用MTA封闭根尖开放部位,形成屏障后热胶垂直加压法充填根管, 6、 12 个月进行复查.结果:1 例失访, 6 个月复诊根尖周透射影增大1 例,根尖周透射影减小20 例,1 例无明显变化.12 个月复诊根尖区透射影消失9 例,根尖周透射影减小5 例,无明显变化2 例.结论:应用MTA封闭根尖和修补根管侧穿的临床短期疗效良好,在根管显微镜下实施有助于提高MTA充填的准确性和密合性.     

Non-surgical retreatment of a failed apicoectomy without retrofilling using white mineral trioxide aggregate as an apical barrier

Root-end resected teeth with persistent apical periodontitis are usually retreated surgically or a combination of non-surgical and surgical retreatment is employed. However, patients are sometimes unwilling to be subjected to a second surgical procedure. The apical barrier technique that is used for apical closure of immature teeth with necrotic pulps may be an alternative to non-surgically retreat a failed apicoectomy. Mineral trioxide aggregate (MTA) has become the material of choice in such cases because of its excellent biocompatibility, sealing ability and osseoinductive properties. This case report describes the non-surgical retreatment of a failed apicoectomy with no attempt at retrofilling of a maxillary central incisor. White MTA was used to induce apical closure of the wide resected apical area. Four-year follow-up examination revealed an asymptomatic, fully functional tooth with a satisfactory healing of the apical lesion. White MTA apical barrier may constitute a reliable and efficient technique to non-surgically retreat teeth with failed root-end resection. The predictability of such a treatment is of great benefit for the patient who is unwilling to be submitted to a second surgical procedure.     

Fracture resistance of immature teeth filled with BioAggregate,mineral trioxide aggregate and calcium hydroxide

Abstract – Background: The aim of this in vitro study was to assess the long‐term fracture resistance of human immature permanent teeth filled with BioAggregate (BA), mineral trioxide aggregate (MTA) and calcium hydroxide (CH). Materials and methods: The study consisted of single rooted premolar teeth with immature root formation extracted for orthodontic reasons. A total of 28 immature premolars with average root length of 10.7 mm and apical diameter of 3 mm were included in the study. The pulps were extirpated and the canals were prepared using an apical approach. The teeth were randomly assigned to four groups: Group I: DiaRoot^® BA (DiaDent, Burnaby, BC, Canada), Group II: Angelus MTA (MTA‐A; Angelus, Londrina, Brazil), Group III: ProRoot^® MTA (MTA‐PR; Dentsply, Tulsa, OK, USA), Group IV: CH (Sultan Chemists Inc., Englewood, NJ, USA). The teeth were placed in saline solution at 4°C for 1 year. The root of each tooth was then embedded in an acrylic resin block. All specimens were loaded at a crosshead speed of 1 mm min^?1 in an Instron testing machine and the peak loads up to fracture were recorded. Data were analysed statistically by Kruskal–Wallis and Mann–Whitney U‐tests. Results: Mean (±SD) failure loads (MPa) were: 37.69 ± 14.43 for BA group, 32.94 ± 8.15 for MTA‐A group, 28.74 ± 9.49 for MTA‐PR group and 23.18 ± 8.48 for CH group. The BA group exhibited the highest fracture resistance and the CH group showed the lowest resistance to fracture. Significant differences (P < 0.05) in fracture resistance were found between the DiaRoot‐BA and CH groups, and also between the MTA‐A and CH groups. Conclusion: Within the limitations of this study, data suggest that DiaRoot‐BA‐filled immature teeth demonstrate higher fracture resistance than other groups at 1 year. Considering the long‐term risk of cervical root fracture associated with immature teeth, the use of DiaRoot‐BA as a root canal filling material appears to be the most advantageous of the materials tested.     

Clinical outcomes of artificial root-end barriers with mineral trioxide aggregate in teeth with immature apices

The purpose of this retrospective study was to evaluate the clinical outcomes of ProRoot mineral trioxide aggregate used as an artificial apical barrier in teeth with immature apices. Twenty teeth from 19 patients were included in this study. A healed diagnosis was based on periapical index scores of 1 or 2 and no clinical signs or symptoms at recall examinations. Eighty-five percent (17/20) of these teeth were healed, and improvements in periapical index scores at recall appointments were shown to be statistically significant (P < .001, Wilcoxon signed-rank test). Chi-square test indicated that age, gender, primary treatment versus retreatment, presence of preoperative lesion, and differences in recall times did not significantly influence healing outcome. Overall, these results indicated that the mineral trioxide aggregate apical barrier technique is a successful method for obturating teeth with immature apices.     

MTA和iRoot BP plus治疗根尖孔未闭合恒牙根尖周炎的临床疗效分析

目的 探讨和比较生物陶瓷材料无机三氧化矿物凝聚体(mineral trioxide aggregate, MTA)和iRoot BP plus在成年根尖孔未闭合患牙形成根尖屏障中的临床应用效果。方法 将200颗根尖孔未闭合恒牙根尖周炎患牙随机分为两组,分别采用MTA和iRoot BP plus制备根尖屏障。比较两种生物陶瓷材料在制备根尖屏障时的操作时间,分析不同根尖孔破坏类型、根尖区病变范围、根尖区充填情况以及患者年龄段对治疗成功率的影响。结果 iRoot BP plus组制备根尖屏障的操作时间比MTA组短,差异有统计学意义(P<0.05);不同根尖孔破坏类型、根尖区病变范围、根尖区充填情况以及患者年龄段对治疗成功率并无显著影响(P>0.05)。结论 MTA和iRoot BP plus在治疗根尖孔未闭合恒牙根尖周炎的临床效果相似,但iRoot BP plus的操作性更好。     

Calcium hydroxide or mineral trioxide aggregate may be used for the apexification of immature teeth

PURPOSE/QUESTION: To compare the efficacy of mineral trioxide aggregate (MTA) and calcium hydroxide (CH) for the root-end induction of immature teeth. SOURCE OF FUNDING: Information not available. TYPE OF STUDY/DESIGN: Systematic review and meta-analysis of data. LEVEL OF EVIDENCE: Level 2: Limited-quality, patient-oriented evidence. STRENGTH OF RECOMMENDATION GRADE: Grade B: Limited-quality patient-oriented evidence.     

MTA在根尖成形中的应用

目的 :介绍MTA在根尖成形中操作方法及其特点。方法 :选取来我院就诊根尖未闭合、牙髓坏死的年轻恒牙 ,用MTA对其根尖部进行填塞 ,余留空间用牙胶充填。结果 :所有病例在 6月后复诊时 ,无不良症状 ,X片示根尖部喇叭口闭合 ,阴影消失。结论 :MTA在根尖成形方面 ,具有操作方便 ,疗效确切的优点。     

The effect of mineral trioxide aggregate on the apexification and periapical healing of teeth with incomplete root formation

Aim To evaluate the influence of mineral trioxide aggregate (MTA) on apexification and periapical healing of teeth in dogs with incomplete root formation and previously contaminated canals and to verify the necessity of employing calcium hydroxide paste before using MTA. Methodology Twenty premolars from two 6‐month old dogs were used. After access to the root canals and complete removal of the pulp, the canal systems remained exposed to the oral environment for 2 weeks. Canal preparation was then carried out using Hedström files, under irrigation with 1% sodium hypochlorite, 1 mm short of the radiographic apex. After drying, the canals of two premolars in each dog were left empty (control group). The other eight teeth in each animal were divided into two experimental groups. The apical thirds of the canals of group 1 were filled with MTA. In the teeth of group 2, the canals were dressed with a calcium hydroxide–propylene glycol paste. After 1 week, the paste was removed and the apical third was filled with MTA. All teeth were restored with reinforced zinc oxide cement (IRM) and amalgam. The animals were killed 5 months later, and blocks of the teeth and surrounding tissues were submitted to histological processing. The sections were studied to evaluate seven parameters: formation of an apical calcified tissue barrier, level of barrier formation, inflammatory reaction, bone and root resorption, MTA extrusion, and microorganisms. Results of experimental groups were analysed by Wilcoxon's nonparametric tests and by the test of proportions. The critical value of statistical significance was 5%. Results Significant differences (P < 0.05) were found in relation to the position of barrier formation and MTA extrusion. The barrier was formed in the interior of the canal in 69.2% of roots from MTA group only. In group 2, it was formed beyond the limits of the canal walls in 75% of the roots. MTA extrusion occurred mainly in roots from group 2. There was similarity between the groups for the other parameters. Conclusions Mineral trioxide aggregate used after root canal preparation favoured the occurrence of the apexification and periapical healing. The initial use of calcium hydroxide paste was not necessary for apexification to occur, and has shown to be strongly related to the extrusion of MTA and formation of barriers beyond the limits of the root canal walls.