Chotvorrarak Kanet, Danwittayakorn Supatra, Banomyong Danuchit, Suksaphar Warattama
Department of Operative Dentistry and Endodontics, Faculty of Dentistry, Mahidol University, Bangkok, Thailand.
Dental department, Queen Sirikit National Institute of Child Health, Bangkok, Thailand.
Dent Traumatol. 2024 Aug;40(4):389-397. doi: 10.1111/edt.12947. Epub 2024 Mar 8.
This review article describes the methods and clinical recommendations for reinforcing traumatized anterior immature teeth with pulp necrosis treated with mineral trioxide aggregate (MTA) apexification. Traumatic injury can cause pulp necrosis and incomplete root formation in immature teeth. MTA apexification is the treatment of choice for necrotic immature teeth, particularly during the middle or late stages of root development. MTA apexification has a high success rate; however, failures due to cervical or root fractures occasionally occur. The risk of fracture is higher in immature teeth with thin root dentin, particularly those with external root resorption. Furthermore, the loading force from any parafunctional habit also increases fracture risk. Therefore, intra-radicular reinforcement may be necessary after MTA apexification. In vitro, intraradicular restoration with a resin composite/core build-up material or a prefabricated fiber post demonstrated better root reinforcement than root canal obturation materials (i.e., gutta-percha and sealer). However, the root-reinforcement effect of MTA orthograde filling in the entire root canal remains unclear. In vivo, the survival of fractured teeth with intraradicular restorations (resin composite/core build-up material or prefabricated fiber posts) is extremely high. Moreover, the survival of teeth with gutta-percha/sealer obturation or MTA orthograde filling and restoration with resin composite extending into the cervical third of the root canal approximately 1-2 mm below the cemento-enamel junction is acceptably high. Based on this evidence, the remaining tooth/root structure and loading force should be carefully examined when considering intra-radicular reinforcement of immature anterior teeth treated with MTA apexification.
这篇综述文章描述了用三氧化矿物凝聚体（MTA）根尖诱导成形术治疗牙髓坏死的外伤未成熟前牙的强化方法及临床建议。外伤可导致未成熟牙牙髓坏死和牙根形成不全。MTA根尖诱导成形术是坏死未成熟牙的首选治疗方法，尤其是在牙根发育的中晚期。MTA根尖诱导成形术成功率较高；然而，偶尔会发生因颈部或牙根骨折导致的失败情况。牙根牙本质薄的未成熟牙，尤其是那些伴有牙根外吸收的牙齿，骨折风险更高。此外，任何异常功能习惯产生的负荷力也会增加骨折风险。因此，在MTA根尖诱导成形术后可能需要进行根管内强化。在体外，用树脂复合材料/核桩材料或预成纤维桩进行根管内修复显示出比根管充填材料（即牙胶和封闭剂）更好的牙根强化效果。然而，MTA正压充填整个根管的牙根强化效果仍不清楚。在体内，采用根管内修复（树脂复合材料/核桩材料或预成纤维桩）的折断牙存活率极高。此外，采用牙胶/封闭剂充填或MTA正压充填并在牙根颈三分之一处距牙骨质-釉质界下方约1-2毫米处用树脂复合材料进行修复的牙齿存活率也较高。基于这些证据，在考虑对采用MTA根尖诱导成形术治疗的未成熟前牙进行根管内强化时，应仔细检查剩余的牙体/牙根结构和负荷力。
