Mandibular Conduction Anesthesia Apprpached at the Anterior Site of the Mandibular Foramen-Radiographic Study of the Spread of the Local Analgesic Solution and Clinical Evaluation-

传统的下牙槽神经阻滞（传统技术）与神经和血管损伤的风险相关。为了避免此类并发症，我们研究了一种通过将局麻药溶液注入下颌孔前翼下颌间隙（前路技术）进行下牙槽神经阻滞的方法，研究了前路技术的插入角度、局麻药在前路技术下牙槽神经阻滞中的扩散情况，并检查了前路技术的麻醉估计。(1)在计算机断层摄影图像上测量的前路技术的预测插入角在对侧下颌第一磨牙的方向的区域中为60.1 * 7.1*，并且插入深度为约10mm。(2)18名志愿者通过常规或前路技术注射1.8 ml含利多卡因和造影剂的混合物，通过X线透视在矢状面追踪扩散过程，并通过计算机断层扫描在水平面追踪扩散过程。两种技术的翼下颌间隙中造影剂的扩散率相同。结果表明，局麻药迅速扩散到下牙槽神经，并产生麻醉效果，在两种技术。(3)我们对100例拔除下颌磨牙的患者采用前路麻醉，并根据Dobbs和DeVier的麻醉效果评价方法进行评价。结果表明，前路麻醉与常规麻醉效果相当，是一种安全的下牙槽神经阻滞方法。

The conventional inferior alveolar nerve block (conventional technique) is associated with risks of neural and vascular injury. We studied a method for inferior alveolar nerve block by injecting a local anesthetic solution into the pterygomandibular space anterior to the mandibular foramen (anterior technique), with a purpose to avoid such complications.Insertion angle of the anterior technique, the spread of local anesthetic in the inferior alveolar nerve block by the anterior technique was studied, and anesthesia estimation in the anterior technique was examined.(1) The predicted insertion angle of the anterior technique measured on computed tomographic images was 60.1 * 7.1*, in the region of a direction of the contralateral mandibular first molar, and the insertion depth was approximately 10 mm.(2) 18 volunteers were injected with 1.8 ml of a mixture containing lidocaine and contrast medium by either the conventional or the anterior technique, and the course of spread was traced by fluoroscopy in the sagittal plane, and by computed tomography in the horizontal plane. The rates of spread of the contrast medium in the pterygomandibular space for both techniques were the same. The results indicated that the local anesthetic spread rapidly to the inferior alveolar nerve and produced an anesthetic effect in both techniques.(3) We applied the anterior technique to 100 patients for mandibular molar extraction, and assessed the anesthetic effects according to the estimation of Dobbs and DeVier. A success rate was obtained in 74%.The anterior technique achieved the same anesthetic effect as the conventional technique.According to the results, we recommend the anterior technique as a safer alternative for inferior alveolar nerve block.