应用Ｎｄ：ＹＡＧ激光经０．５ｍｍ光导纤维输出对犬牙髓进行处理和相应的组织学观察。结果表明，激光末端输出功率２０Ｗ～３０Ｗ可成功实施冠髓切断术，而根髓未见任何病理损害；应用末端输出功率３０Ｗ～４０Ｗ可对全部牙髓产生完全汽化效果，牙齿本身和牙周组织未见不可逆性病理改变。实验结果为临床应用此技术实行冠髓切断术和全髓失活术提供了实验依据和实践经验，并为今后此方面系统研究奠定了基础。 Nd: YAG laser was used to treat the canine pulp after 0.5 mm optical fiber output and the corresponding histological observation. The results showed that the laser output power of 20W ~ 30W successful implementation of the coronary artery transection without any pathological damage to the root marrow; application of the end of the output power of 30W ~ 40W can produce complete vaporization of all pulp, the teeth themselves and periodontal tissue No irreversible pathological changes. The experimental results provide experimental basis and practical experience for the clinical application of this technique in the implementation of the technique of coronallotomy and total inactivation and lay the foundation for future systematic research in this field.