Er：YAG激光制备窝洞对树脂充填微渗漏的影响

目的应用离体牙比较复合树脂与Er：YAG激光及传统牙钻制备窝洞洞壁间微渗漏的差异。方法将30颗前磨牙随机分为3组,每组10颗牙,制备Ⅴ类洞：Ⅰ组牙钻预备加酸蚀处理;Ⅱ组单纯激光预备组、Ⅲ组激光预备加酸蚀处理组,经冷热循环染色后,在体视显微镜下记录微渗漏程度并应用非参数统计方法分析数据。结果各组内颈壁的染料渗透情况均比壁明显（P〈0.05）;在壁,单纯激光预备组产生的微渗漏最严重（P〈0.05）,激光预备加酸蚀处理组与牙钻预备加酸蚀处理组微渗漏无统计学差异;在颈壁,三组充填体边缘微渗漏情况无统计学差异。结论Er：YAG激光可代替牙钻备洞,结合酸蚀处理与充填体有良好的密合度。

The effect of Er:YAG laser irradiation on the microleakage of Class V composite resin restoration

Objective To examine the microleakage of composite resin filled Class V cavities prepared by a high -speed dental bur or Er： YAG laser in vitro. Methods Thirty sound extracted human premolar teeth were included and randomly and equally divided into three groups. In group Ⅰ , Class Ⅴ cavities were prepared by dental drill at high - speed and followed by acid -etching, while in group Ⅱ , Class V cavities were prepared by Er：YAG laser and in group Ⅲ, Class Vcavities were prepared by Er：YAG laser and followed by acid- etching. All the cavities were restored with composite resin. The specimens were thermocycled, immersed in 0.5% fuchsin dye, and sectioned. The microleakage was scored using an optical microscope. Data were analyzed using non - parametric statistical test. Results Microleakage in cervical regions was more severe than that in the occlusal in all the groups （ P 〈 0.05 ）. On the eeclusal walls, cavities treated exclusively by the Er ： YAG laser （ group Ⅱ ） provided the poorest marginal sealing; bur ＋ acid - etching （ group Ⅰ ） was similar to Er： YAG laser ＋ acid - etching （ group Ⅲ ）. On the gingival walls, no statistical differences were found among the three groups. Conclusion Laser irradiation is a valid alternative to bur for preparation cavities for composite resin restoration.