两种排龈方法排龈效果的数字化分析

目的 数字化分析比较半导体激光排龈及单线排龈法的临床排龈效果，即排龈疼痛度分析以及对游离龈龈沟宽度（sulcus width，SW）和牙龈退缩量（gingival recession，GR）的影响。方法 选择需行固定修复的患者42例，共计52颗患牙，随机分为半导体激光排龈组及单线排龈组，选择26颗正常牙作为空白对照组。采用VRS疼痛数字分级法，评估两种排龈法疼痛度；采用3Shape扫描仪制取排龈前及排龈后即刻、1周、6周的数字化模型，在geomagic qualify 2014软件中，分析比较两种排龈法排龈后SW、GR0、GR1、GR6。结果 半导体激光排龈组疼痛度低于单线排龈组（P<0.05）；半导体激光组SW颊=（0.394 2±0.087 3）mm、SW腭=（0.397 4±0.086 8）mm，大于单线排龈组SW颊=（0.322 8±0.057 3）mm、SW腭=（0.306 0±0.050 6）mm（P<0.05）；半导体激光组GR0＝（0.342 5±0.027 9）mm、GR1＝（0.162 5±0.056 9）mm、GR6＝（0.239 3±0.020 6）mm大于单线排龈组GR0＝（0.273 0±0.018 7）mm、GR1＝（0.145 9±0.030 8）mm、GR6＝（0.162 5±0.015 9）mm（P<0.05）。结论 半导体激光排龈疼痛度较低，单线排龈法及半导体激光排龈法均能达到良好的龈沟宽度，但二者均会导致永久性龈退缩，且半导体激光排龈后牙龈退缩量较单线排龈法大，故针对厚龈型牙龈建议使用单线排龈。但对于疼痛较为敏感的患者，也可考虑使用激光排龈。

Digital analysis of gingival retraction effects following two methods

Objective To apply digital analysis to compare the clinical gingival retraction effects, including gingival pain degree, sulcus width (SW) and gingival recession (GR), between diode laser method and single cord method. Methods A total of 52 teeth were selected from 42 patients who needed fixed partial denture restoration. They were randomly divided into two groups, diode laser gingival retraction group and single cord gingival retraction group. Twenty six normal teeth were selected as blank control group. VRS digital pain grading method was used to evaluate the pain degree of the two gingival retraction methods, and 3shape scanner was chosen to rebuild digital models before and after gingival retraction at the time point of 0 week, 1st week and 6th week. Finally, the acquired data was input into geomagic qualify 2014 software to compare the gingival effects SW, GR0, GR1 and GR6 before and after gingival displacement. Results The pain level of the diode laser group was lower than that of the single cord group (P<0.05); the SW of diode laser group (buccal (0.394 2±0.087 3)mm, palatal (0.397 4±0.086 8)mm) was greater than the single cord group (buccal (0.322 8±0.057 3) mm, palatal side (0.306 0±0.050 6)mm) (P<0.05); the GR0 (0.342 5±0.027 9)mm, GR1 (0.162 5±0.056 9)mm, and GR6 (0.239 3±0.020 6)mm of the diode laser group were larger than those of the single cord group, GR0 (0.273 0±0.018 7)mm, GR1 (0.145 9±0.030 8)mm, GR6 (0.162 5±0.015 9)mm (P<0.05). Conclusion The diode laser method can lead to lower pain degree. Both two methods can achieve ideal sulcus width, but permanent gingival recession will be caused. The amount of gingival recession after diode laser gingival retraction is larger. Therefore, it is recommended to use single cord method for patients with thick gums, while for patients sensitive to pain, laser method could also be considered.