Jamal Basem T, Taub Daniel, Gold Lionel
Department of Molecular and Cell Biology, Boston University Medical Center, Boston, MA 02118, USA.
J Oral Maxillofac Surg. 2009 Sep;67(9):1821-5. doi: 10.1016/j.joms.2009.04.022.
The purpose of this article is to evaluate whether hemimandibulectomy with disarticulation predisposes the patient to the development of contralateral coronoid hyperplasia, thereby justifying a coronoidectomy procedure for these patients to improve jaw function and mouth opening and decrease the length of postoperative physical therapy.
Five patients who had hemimandibular resection with disarticulation for odontogenic cysts and benign tumors followed by hemimandibular graft reconstruction with either a cadaveric hemimandible or an iliac crest bone graft, or both, were retrospectively reviewed. The Levandoski panoramic radiograph analysis, which has been proven to be useful in evaluating facial asymmetry and hyperplasia of the coronoid process in adults, was used to analyze preoperative panoramic radiographs as well as those obtained at postoperative months 3 and 6.
All patients performed postoperative range-of-motion exercises for treatment of limited mouth opening in a range between 12 to 24 mm lasting up to 3 or 4 months. Two patients had prolonged trismus with a maximum interincisal opening of about 30 mm. The mean preoperative Kr' (koronion')-Go' (gonion')/Cd' (condylion')-Go' ratio was 0.92. A minimal increase in the Kr'-Go'/Cd'-Go' ratio was noted at postoperative months 3 and 6, with mean values of 0.95 and 0.96, respectively. Only 3 patients showed minimal elongation of the coronoid process, with 1 having a notable increase from 0.91 to 1.04.
Trismus, the clinical sign of restricted jaw movement, can result from pathology in a variety of structures around the oral cavity. Among the general population, the normal Kr'-Go'/Cd'-Go' ratio was found to be less than 1.07, which coincides with the preoperative mean Kr'-Go'/Cd'-Go' ratio of 0.92 in our series. Our study sample showed a minimal increase in the Kr'-Go'/Cd'-Go' ratio over the first 6 postoperative months, but the number of patients was not sufficient to conclude causality. The etiology of coronoid hyperplasia remains unclear, but the role of increased temporalis muscle activity cannot be excluded. We recommend the Levandoski analysis for patients who had hemimandibulectomy with disarticulation who complain of prolonged limited mouth opening. We also recommend considering coronoidectomy as a treatment option for those with persistent trismus and radiographic signs of coronoid hyperplasia.
本文旨在评估半侧下颌骨切除术伴关节离断术是否会使患者易患对侧冠状突增生，从而证明对这些患者进行冠状突切除术以改善颌骨功能和开口度并缩短术后物理治疗时间的合理性。
回顾性分析5例因牙源性囊肿和良性肿瘤行半侧下颌骨切除伴关节离断术，随后采用尸体半侧下颌骨或髂嵴骨移植或两者联合进行半侧下颌骨移植重建的患者。Levandoski全景X线片分析已被证明可用于评估成人面部不对称和冠状突增生，用于分析术前全景X线片以及术后3个月和6个月获得的X线片。
所有患者均进行了术后活动度锻炼以治疗开口受限，开口度在12至24毫米之间，持续3至4个月。2例患者出现持续性牙关紧闭，最大切牙间开口约为30毫米。术前平均Kr'（冠状突点'）-Go'（下颌角点'）/Cd'（髁突点'）-Go'比值为0.92。术后3个月和6个月时，Kr'-Go'/Cd'-Go'比值略有增加，平均值分别为0.95和0.96。只有3例患者冠状突有轻微延长，其中1例从0.91显著增加到1.04。
牙关紧闭是颌骨运动受限的临床体征，可由口腔周围多种结构的病变引起。在一般人群中，正常的Kr'-Go'/Cd'-Go'比值小于1.07，这与我们系列研究中术前平均Kr'-Go'/Cd'-Go'比值0.92相符。我们的研究样本在术后前6个月Kr'-Go'/Cd'-Go'比值略有增加，但患者数量不足以得出因果关系。冠状突增生的病因尚不清楚，但不能排除颞肌活动增加的作用。对于行半侧下颌骨切除伴关节离断术且抱怨开口受限持续时间较长的患者，我们建议采用Levandoski分析。对于有持续性牙关紧闭和冠状突增生影像学表现的患者，我们也建议考虑将冠状突切除术作为一种治疗选择。
