目的

比较拔除上前磨牙时采用单牙无痛局部麻醉系统（STA）行牙周韧带（PDL）内注射麻醉和常规金属注射器颊腭双侧局部浸润麻醉在注射及拔牙过程中疼痛情况和麻醉效果。

方法

选择100 例因为正畸需要拔除双侧上前恒磨牙的患者为研究对象，随机选择其中一侧作为试验牙，另一侧作为对照牙；实验组应用计算机控制STA 进行盐酸阿替卡因PDL 内注射麻醉，对照组采用常规金属注射器进行盐酸阿替卡因颊腭双侧局部浸润麻醉。麻醉5 min 后进行拔牙手术。 利用直观模拟标度尺（VAS）及问卷获得患者麻醉注射及拔牙时的痛觉数据和颊部软组织是否麻木不适数据。

结果

实验组和对照组麻醉注射疼痛感觉VAS 值分别是（0.4011±0.556）、（4.1038±1.512），两组注射疼痛感觉比较差异有统计学意义（P ＜0.01）；而实验组与对照组在麻醉镇痛成功率方面比较差异无统计学意义（P ＞0.05）；实验组只有2%患者有颊侧软组织麻木不适感，而对照组100%患者有颊侧软组织麻木不适感，两者差异有统计学意义（P ＜0.01）。

结论

在上前磨牙拔除中，应用STA-PDL 注射麻醉可以达到良好的麻醉效果，同时麻醉注射时疼痛轻微，对邻近颊部软组织功能影响小，麻醉药物用量较少。

Objective

To compare the effects of two local anesthesia （the periodontal ligament anesthesia and traditional bilateral local infiltration anesthesia） for the extraction of upper premolar.

Methods

100 patients had bilateral extraction of upper premolar. Randomly one side was selected as test tooth， the other side as the control tooth. In test group， the patients received the periodontal ligament anesthesia of articaine hydrochloride through using STA computer-controlled local anesthetic delivery system. In control group， the patients received bilateral local infiltration anesthesia of articaine hydrochloride. The teeth were extracted after 5 minutes. All patients completed visual analog scales （VAS） after injection and extraction. Data relating to numbness of the cheek soft tissue was obtained on a questionnaire.

Results

The VAS of injection pain was （0.4011±0.556） in test group and （4.1038±1.512） in control group. There was a statistically significant difference between the two groups （P ＜0.01）. But there was no statistical significance between achievement ratio of test group and control group （P ＞0.05）. The result of questionnaire showed numbness rates of the cheek soft tissue of test group and control group were 2% and 100% respectively， there was a significant difference （P ＜0.01）.

Conclusion

The periodontal ligament anesthesia by using STA computer-controlled local anesthetic delivery system can attain good anesthetic effect， at the same time it has slight anesthetic injection pain，needs less the amount of local anesthetic， and the affect to soft tissue of the cheek is little.