Renton Tara
King's College London Dental Institute, King's College Hospital Foundation Trust, Denmark Hill Campus, Bessemer Road, London SE5 9RS, UK.
Dent Update. 2013 Jun;40(5):362-4, 366-8. doi: 10.12968/denu.2013.40.5.362.
Decoronation of high risk mandibular third molars (M3Ms) has become common practice in parts of UK and USA. With the introduction of Cone Beam CT scanning, there has been an evolution in the practice, with avoidance of unnecessary coronectomies based on CBCT findings. Also, additional anatomical features found only on CBCTs have introduced possible additional indications to undertake intentional coronectomy. Trigeminal nerve injury is the most problematic consequence of dental surgical procedures with major medico-legal implications. Iatrogenic injuries to the third division of the trigeminal nerve remain a common and complex clinical problem. Altered sensation and pain in the orofacial region may interfere with speaking, eating, kissing, shaving, applying make-up, toothbrushing and drinking; namely just about every social interaction we take for granted. Usually after oral rehabilitation, the patient expects and experiences significant improvements, not only regarding jaw function, but also in relation to dental, facial, and even overall body image. Thus these injuries have a significant negative effect on the patient's self-image and quality of life and the iatrogenesis of these injuries lead to significant psychological effects.
Coronectomy is an alternative procedure to complete removal of a mandibular third molar in situations where there is high risk of damage to the inferior alveolar nerve.
在英国和美国的部分地区，对高风险下颌第三磨牙（M3M）进行去冠术已成为常见做法。随着锥形束CT扫描的引入，这种做法有所演变，基于CBCT检查结果避免了不必要的冠切除术。此外，仅在CBCT上发现的额外解剖特征引入了进行意向性冠切除术的可能额外指征。三叉神经损伤是牙科手术中最具问题的后果，具有重大的医疗法律影响。医源性三叉神经第三支损伤仍然是一个常见且复杂的临床问题。口面部区域的感觉改变和疼痛可能会干扰说话、进食、亲吻、剃须、化妆、刷牙和饮水；也就是说，几乎会干扰我们习以为常的每一种社交互动。通常在口腔康复后，患者不仅期望而且会体验到显著改善，不仅在颌骨功能方面，而且在牙齿、面部乃至整体身体形象方面。因此，这些损伤会对患者的自我形象和生活质量产生重大负面影响，而这些损伤的医源性因素会导致显著的心理影响。
在存在下牙槽神经损伤高风险的情况下，冠切除术是完全拔除下颌第三磨牙的一种替代手术。
