Baltimore, Bethesda, and Laurel, Md.; and Boston, Mass. From the Departments of Plastic and Reconstructive Surgery and Radiology, Johns Hopkins University School of Medicine; Department of Otolaryngology-Head and Neck Surgery, Walter Reed National Military Medical Center; Harvard School of Dental Medicine, Department of Oral and Maxillofacial Surgery, Massachusetts General Hospital; Research and Engineering Development Department, Robotics and Autonomy Group, Johns Hopkins Applied Physics Laboratory; and Naval Postgraduate Dental School, 3D Medical Applications Center, Department of Radiology, Walter Reed National Military Medical Center.
Plast Reconstr Surg. 2014 May;133(5):1138-1151. doi: 10.1097/PRS.0000000000000110.
Le Fort-based, maxillofacial allotransplantation is a reconstructive alternative gaining clinical acceptance. However, the vast majority of single-jaw transplant recipients demonstrate less-than-ideal skeletal and dental relationships, with suboptimal aesthetic harmony. The purpose of this study was to investigate reproducible cephalometric landmarks in a large-animal model, where refinement of computer-assisted planning, intraoperative navigational guidance, translational bone osteotomies, and comparative surgical techniques could be performed.
Cephalometric landmarks that could be translated into the human craniomaxillofacial skeleton, and that would remain reliable following maxillofacial osteotomies with midfacial alloflap inset, were sought on six miniature swine. Le Fort I- and Le Fort III-based alloflaps were harvested in swine with osteotomies, and all alloflaps were either autoreplanted or transplanted. Cephalometric analyses were performed on lateral cephalograms preoperatively and postoperatively. Critical cephalometric data sets were identified with the assistance of surgical planning and virtual prediction software and evaluated for reliability and translational predictability.
Several pertinent landmarks and human analogues were identified, including pronasale, zygion, parietale, gonion, gnathion, lower incisor base, and alveolare. Parietale-pronasale-alveolare and parietale-pronasale-lower incisor base were found to be reliable correlates of sellion-nasion-A point angle and sellion-nasion-B point angle measurements in humans, respectively.
There is a set of reliable cephalometric landmarks and measurement angles pertinent for use within a translational large-animal model. These craniomaxillofacial landmarks will enable development of novel navigational software technology, improve cutting guide designs, and facilitate exploration of new avenues for investigation and collaboration.
基于 Le Fort 的颌面同种异体移植是一种越来越被临床接受的重建替代方法。然而，绝大多数单颌移植受者的骨骼和牙齿关系都不理想，美学协调性也不理想。本研究的目的是在大型动物模型中研究可重复的头影测量标志，在该模型中可以对计算机辅助规划、术中导航指导、平移性骨切开术和比较性外科技术进行改进。
寻找可以转化为人类颅颌面骨骼的头影测量标志，并且在进行颌面截骨术和中面部同种异体皮瓣植入后仍保持可靠的标志。在六头小型猪中进行了 Le Fort I 和 Le Fort III 型同种异体皮瓣的采集，在猪中进行了截骨术，所有同种异体皮瓣均被自体移植或异体移植。在术前和术后的侧位头颅侧位片上进行头影测量分析。借助手术规划和虚拟预测软件确定了关键的头影测量数据集，并评估其可靠性和可预测性。
确定了几个相关的标志和人类类似物，包括鼻前棘、颧骨突、顶骨、下颌角、颏下点、下切牙基和牙槽。顶骨-鼻前棘-牙槽和顶骨-鼻前棘-下切牙基分别与人类的蝶鞍-鼻根点（Sella-Nasion A）角和蝶鞍-鼻根点（B）角的可靠相关性。
存在一组可靠的头影测量标志和相关的测量角度，可用于平移性大型动物模型中。这些颅颌面标志将能够开发新的导航软件技术，改进切割引导设计，并促进新的探索途径的研究和合作。
