Is there a consensus for CBCT use in Orthodontics?

This article aims to discuss current evidence and recommendations for cone-beam computed tomography (CBCT) in Orthodontics. In comparison to conventional radiograph, CBCT has higher radiation doses and, for this reason, is not a standard method of diagnosis in Orthodontics. Routine use of CBCT in substitution to conventional radiograph is considered an unaccepted practice. CBCT should be indicated with criteria only after clinical examination has been performed and when the benefits for diagnosis and treatment planning exceed the risks of a greater radiation dose. It should be requested only when there is a potential to provide new information not demonstrated by conventional scans, when it modifies treatment plan or favors treatment execution. The most frequent indication of CBCT in Orthodontics, with some evidence on its clinical efficacy, includes retained/impacted permanent teeth; severe craniofacial anomalies; severe facial discrepancies with indication of orthodontic-surgical treatment; and bone irregularities or malformation of TMJ accompanied by signs and symptoms. In exceptional cases of adult patients when critical tooth movement are planned in regions with deficient buccolingual thickness of the alveolar ridge, CBCT can be indicated provided that there is a perspective of changes in orthodontic treatment planning.

本文旨在探讨正畸学领域中锥形束计算机断层扫描（cone-beam computed tomography, CBCT）的现有循证证据与临床应用建议。相较于传统X线摄影，CBCT的辐射剂量更高，因此并非正畸学领域的标准诊断手段。常规使用CBCT替代传统X线片的做法被视为不被认可的临床操作。仅在完成临床检查，且诊断与治疗规划的获益超过更高辐射剂量所带来的风险时，方可依据临床指征使用CBCT。仅当CBCT能够提供传统影像学检查无法展现的新信息、可修改治疗方案或有助于治疗实施时，方可申请使用CBCT。现有临床证据支持的正畸学领域CBCT最常见适应证包括：滞留/阻生恒牙、严重颅面畸形、需实施正畸-正颌联合治疗的重度颜面不协调，以及伴临床体征与症状的颞下颌关节（temporomandibular joint, TMJ）骨异常或畸形。对于成人患者的特殊病例，若计划在牙槽嵴颊舌径厚度不足的区域实施复杂牙移动，且正畸治疗方案存在调整空间时，可考虑使用CBCT。