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有关。为了避免此类并发症的发生，我们研究了一种通过在下颌孔前翼下颌间隙注射局麻溶液进行下牙槽神经阻滞的方法（前技术）。研究了前路技术的入路角度、局麻在下牙槽神经阻滞中的扩散情况，并对前路技术的麻醉估计进行了探讨。(1)计算机断层图像测得的前路技术预测插入角度为60.1 * 7.1*，在对侧下颌第一磨牙的一个方向区域，插入深度约为10 mm。(2)对18名志愿者分别采用常规或前路技术注射含利多卡因和造影剂的混合物1.8 ml，并在矢状面透视追踪其扩散过程。在水平面上进行计算机断层扫描。两种技术的对比剂在翼状下颌间隙的扩散率是相同的。结果表明，两种方法的局麻药均能迅速扩散到下肺泡神经，并产生麻醉效果。(3)应用前路技术对100例患者进行下颌磨牙拔除，并根据Dobbs和DeVier的估计评估麻醉效果。成功率为74%。前路技术达到了与传统技术相同的麻醉效果。根据结果，我们推荐前路技术作为下牙槽神经阻滞的一种更安全的选择。

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.