Goto Shingo, Kurita Kenichi, Kuroiwa Yuichiro, Hatano Yuko, Kohara Keitaro, Izumi Masahiro, Ariji Eiichiro
Department of Oral and Maxillofacial Surgery, Aichi Gakuin University School of Dentistry, Nagoya, Japan.
J Oral Maxillofac Surg. 2012 May;70(5):1023-9. doi: 10.1016/j.joms.2011.09.037. Epub 2011 Dec 30.
Coronectomy is performed when contact between the mandibular third molar apex and the inferior alveolar nerve is suspected. The efficacy of coronectomy compared with conventional tooth extraction has been recognized in recent years. However, few studies have reported the postoperative prognosis of roots remaining in the bone or surrounding tissue. Therefore, a clinical evaluation was performed with dental computed tomographic imaging of the coronectomy sites 1 year after the procedure.
This study investigated 101 patients (116 teeth) who underwent a coronectomy from March 2006 through December 2009. They were recalled 1 year later for a clinical evaluation and dental computed tomographic imaging of the coronectomy sites. The clinical evaluation was based on palpation and macroscopic findings.
In 99.2% (115 teeth) of the studied cases, the soft tissue distal to the mandibular second molar was healthy and the retained roots were covered by bone. In 1 case (0.8%), an eruption of roots into the oral cavity was observed; however, no inflammation was observed in the nearby soft tissue. In all 116 teeth, no transmission images indicative of periapical lesions, which usually result from necrosis of the pulp, were observed in the apical area of the retained roots.
The absence of transmission images indicative of periapical lesions and the presence of bone covering more than 99.2% (115 teeth) of the retained roots showed a safe postoperative course at the 1-year follow-up after coronectomy.
当怀疑下颌第三磨牙根尖与下牙槽神经存在接触时，可进行冠切除术。近年来，冠切除术与传统拔牙术相比的疗效已得到认可。然而，很少有研究报道残留在骨组织或周围组织中的牙根的术后预后情况。因此，在冠切除术后1年，对手术部位进行牙科计算机断层扫描成像，以进行临床评估。
本研究调查了2006年3月至2009年12月期间接受冠切除术的101例患者（116颗牙齿）。1年后对他们进行召回，以对冠切除部位进行临床评估和牙科计算机断层扫描成像。临床评估基于触诊和宏观检查结果。
在99.2%（115颗牙齿）的研究病例中，下颌第二磨牙远中的软组织健康，残留牙根被骨组织覆盖。在1例（0.8%）病例中，观察到牙根萌出至口腔内；然而，在附近软组织中未观察到炎症。在所有116颗牙齿中，在残留牙根的根尖区域均未观察到提示根尖周病变的透射影像，根尖周病变通常由牙髓坏死引起。
在冠切除术后一年的随访中，未观察到提示根尖周病变的透射影像，且超过99.2%（115颗牙齿）的残留牙根有骨组织覆盖，表明术后过程安全。
