Nasrabadi Navid, Yazdani Atoosa, Mehrabani Mahgol
Department of Endodontics, School of Dentistry, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Dentist, Private Practice, Tehran, Iran.
Iran Endod J. 2025;20(1):e19. doi: 10.22037/iej.v20i1.46885. Epub 2025 Mar 11.
Dens invagination (DI) is a developmental dental anomaly characterized by the infolding of the enamel organ into the dental papilla. Type IIIb DI, involving deep invagination that extends apically along the root, poses significant challenges in endodontic treatment due to its complex anatomy. We describe a case of type IIIb DI in a 13-year-old female referred with the chief complaint of spontaneous pain on the left maxillary lateral incisor. Clinical examinations showed tenderness to percussion and palpation as well as a positive response to cold test with lingering pain. Cone-beam computed tomography (CBCT) confirmed the presence of type IIIb DI associated with a periapical lesion. The final diagnosis was irreversible pulpitis with apical periodontitis for main canal (distal) and pulpless and infected root canal system with secondary acute apical periodontitis according to Abbott classification for the other canal. Two separate access cavities were prepared with the guidance of CBCT. Root canal therapy was performed on both root canals, using photodynamic therapy (PDT) and ultrasonic-activated sodium hypochlorite for enhanced disinfection. Calcium-enriched mixture cement was used to obturate the apical third, followed by thermoplastic gutta-percha in the middle and coronal thirds. The patient was asymptomatic at 6- and 12-month follow-ups, with radiographic evidence of complete healing. This case highlights the effectiveness of conservative endodontic treatment using PTD in managing complex DI cases, with a focus on maintaining tooth structure and achieving long-term success.
牙内陷（DI）是一种牙发育异常，其特征为成釉器向内折叠进入牙乳头。IIIb型牙内陷涉及沿牙根向根尖方向延伸的深度内陷，因其复杂的解剖结构，在根管治疗中带来了重大挑战。我们描述了一例13岁女性的IIIb型牙内陷病例，该患者因左上侧切牙自发痛为主诉前来就诊。临床检查显示叩诊和触诊时有压痛，冷测试呈阳性且疼痛持续。锥形束计算机断层扫描（CBCT）证实存在与根尖周病变相关的IIIb型牙内陷。根据Abbott对另一根管的分类，最终诊断为主根管（远中）为不可逆性牙髓炎伴根尖周炎，另一根管为牙髓坏死且感染的根管系统伴继发性急性根尖周炎。在CBCT引导下制备了两个独立的进入腔。对两根根管均进行了根管治疗，使用光动力疗法（PDT）和超声激活次氯酸钠以增强消毒效果。使用富钙混合水门汀封闭根尖三分之一，随后在根管中部和冠部三分之一使用热塑性牙胶进行充填。在6个月和12个月的随访中患者无症状，影像学显示完全愈合。该病例突出了使用光动力疗法进行保守根管治疗在处理复杂牙内陷病例中的有效性，重点在于保留牙齿结构并实现长期成功。
