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。     

Er：YAG激光备洞与树脂充填微渗漏的实验研究

目的：评价Er：YAG激光备洞对树脂充填材料边缘微渗漏的影响。方法：选择48颗年轻前磨牙随机分成4组,每组12颗牙,用Er：YAG激光或高速牙钻制备ⅴ类洞。对照组：牙钻备洞＋35%磷酸酸蚀;实验1组：激光备洞＋35%磷酸酸蚀;实验2组：激光备洞＋自酸蚀粘接;实验3组：单纯激光备洞。树脂充填,经冷热循环试验后染色24h,体视显微镜下观察微渗漏,统计学处理数据。结果：龈壁的染料渗透,4组间无统计学差异;壁的染料渗透,以实验3组较明显,与对照组、实验1、2组有统计学差异（P〈0.05）;各组内壁的染料渗透均比龈壁轻,但没有统计学差异。结论：Er：YAG激光备洞,35%磷酸酸蚀或自酸蚀粘接处理可减少洞壁与树脂充填边缘的微渗漏。     

脉冲Er：YAG激光照射对窝沟封闭微渗漏的影响

目的观察脉冲Er：YAG激光照射对窝沟封闭微渗漏的影响。方法选用因正畸需要拔除的上颌第一双尖牙30颗,随机分为A、B、C组,每组10颗。A组为对照组,采用35%磷酸酸蚀后窝沟封闭;B组采用脉冲Er：YAG激光扫描式照射面窝沟,吹干后直接进行封闭;C组先采用脉冲Er：YAG激光扫描式照射面窝沟,再进行35%磷酸酸蚀后窝沟封闭。三组样本通过染料浸染后使用光学显微镜观察窝沟封闭微渗漏。结果 B组微渗漏显著高于A组和C组,A组和C组微渗漏差别无统计学意义。结论在窝沟封闭操作中,脉冲Er：YAG激光照射不能替代磷酸酸蚀。     

Er:YAG激光照射对窝沟封闭剂微渗漏影响的研究

目的通过体外观察Er:YAG激光照射对窝沟封闭剂微渗漏的影响,探讨其做为窝沟封闭前釉质预处理方式的可能性。方法以20颗离体磨牙做为标本,随机分成4组,每组5颗,窝沟分别采用下列方式处理,A组:杯状刷清洗后酸蚀,B组:钻处理后酸蚀,C组:Er:YAG激光照射,D组:Er:YAG激光照射后酸蚀,然后窝沟封闭,冷热循环,染料渗透,切片,体视显微镜观察各组窝沟封闭剂与釉质面的微渗漏情况。结果单纯Er:YAG激光照射组微渗漏最严重(P<0.05),3种方式预备窝沟经酸蚀后窝沟封闭剂边缘微渗漏无显著性差异(P>0.05)。结论Er:YAG激光照射后的窝沟放置窝沟封闭剂前还应酸蚀。     

Er:YAG激光和Nd:YAG激光辅助的牙漂白对树脂充填体粘接强度和边缘微渗漏的影响

目的：评价Er:YAG激光和Nd:YAG激光辅助的牙漂白对釉质表面树脂充填体粘接强度和边缘微渗漏的影响。方法：将离体牙制备成釉质测试试件（n=64）后随机分为4组（n=16）,包括对照组、传统漂白组、Er:YAG激光辅助的漂白组和Nd:YAG激光辅助的漂白组。4组试件分别处理后,检测其釉质表面树脂充填体的剪切粘接强度（n=8）和微渗漏深度（n=8）,利用体视显微镜观察各组试件的断裂模式。采用SPSS 26.0软件包对数据进行统计学分析。结果：与对照组相比,传统漂白后釉质表面树脂充填体的粘接强度显著下降,边缘微渗漏显著增加(P<0.05);Er:YAG激光辅助的漂白后釉质表面充填体的剪切粘接强度和微渗漏深度与对照组相比无显著差异（P>0.05）,Nd:YAG激光辅助的漂白后树脂充填体的剪切粘接强度显著下降（P<0.05）,但其边缘微渗漏深度与对照组相比无显著差异(P>0.05)。4组试件的粘接断裂模式主要为粘接界面断裂。结论：相比传统漂白方法,激光辅助的牙漂白对树脂充填体粘接强度和微渗漏的影响较小,具有一定的临床优势。     

Er,Cr:YSGG激光制洞对光固化复合树脂边缘微渗漏的影响

目的:比较在自酸蚀黏结剂的应用条件下,Er,Cr:YSGG激光制备与传统牙钻制备离体牙牙颈部洞对光固化复合树脂边缘微渗漏的影响。方法:将20个因正畸拔除的新鲜完整无龋损、无隐裂、无充填物的前磨牙随机分为两组(n=10),分别使用牙钻和Er,Cr:YSGG激光制备牙颈部洞。窝洞制备后均匀涂覆FL-BOND,用TPH复合树脂进行分层充填,打磨、抛光,37℃生理盐水中存放7 d后,进行500次温度循环实验(5±2)℃—(55±2)℃。将上述所有样本置0.5%碱性品红液中室温浸泡24 h后,沿牙体长轴通过修复体正中纵行剖开,采用染料渗入法和扫描电镜方法观察充填体微渗漏情况,运用SPSS 11.0软件包进行统计学处理。结果:牙钻制备组与激光组相比,无论牙合壁还是龈壁的染料渗入评分和边缘微缝隙宽度均无显著性差异(P>0.05)。结论:在自酸蚀黏结剂的应用条件下,Er,Cr:YSGG激光制洞不能显著减少光固化复合树脂边缘微渗漏的发生。     

Nd：YAG激光对Dyract复合体充填微渗漏的影响

目的　观察Nd :YAG激光照射洞缘牙釉质对复合体Dyract充填微渗漏的影响。方法　新鲜拔除的完整离体牙 5 0颗 ,随机分为实验组 ( 2 6颗 )和对照组 ( 2 4颗 )。在样本牙的颊舌面制备V类洞 ,对照组常规完成Dyract充填 ,实验组用Nd :YAG激光照射洞缘牙釉质后再行Dyract充填。所有样本经冷热循环处理后 ,再进行微渗漏实验。用体视显微镜和SEM观察并拍照记录。结果　激光光蚀组充填体边缘微渗漏比对照组明显低 (P <0 .0 5 )。微渗漏实验与扫描电镜观察结果一致。结论　Nd :YAG激光的光蚀作用有助于增强复合体Dyract与牙体组织的结合 ,改善边缘封闭 ,减少微渗漏 ,有利于充填成功     

Er:YAG激光桩道荡洗技术对纤维桩微渗漏的影响

目的:研究Er:YAG激光桩道荡洗技术对纤维桩微渗漏的影响.方法:选取大小形状相似的30颗单根管离体上前牙,经常规根管治疗后,根管上段2/3行桩道预备.按照荡洗技术随机平均分成3组:生理盐水组、2.5％次氯酸钠溶液组、Er:YAG激光联合2.5％次氯酸钠溶液组.纸尖干燥桩道并完成纤维桩粘接.截取离体牙釉牙骨质界至下方6...     

Nd:YAG激光对不同充填材料牙本质边缘微渗漏的影响

目的 评价Nd:YAG激光对不同充填材料与牙本质之间边缘微渗漏的影响。方法 选用人离体前磨牙36颗,制备V类洞,随机分为激光组和对照组,激光组使用80 rnJ、10 Hz脉冲Nd:YAG激光照射后,分别用全酸蚀粘接树脂、自酸蚀粘接树脂和玻璃离子充填洞型,对照组不使用激光,同样用如前所述的3种材料充填洞型。将所有标本浸泡在2%亚甲基蓝溶液中24 h后,用金刚砂片从颊舌向通过充填物中央纵向切开牙体,显微镜下观察龈壁染料渗透的深度。采用SAS8.0软件对数据进行统计学处理。结果 经Nd:YAG激光照射后尽管3种材料与牙本质之间微渗漏程度均有降低趋势,但只有玻璃离子组激光照射后较未照射组微渗漏降低具有统计学意义(P<0.05)。结论 脉冲Nd:YAG激光照射牙本质壁,在一定程度上可能会减少玻璃离子充填材料与洞壁的微渗漏。     

复合树脂与Er,Cr∶YSGG激光制备的窝洞壁间微渗漏评价

目的:研究复合树脂与Er,Cr∶YSGG(掺铒铬钇钪镓石榴石)激光制备的窝洞壁间微渗漏.方法:将30颗离体前磨牙随机分为3组(n=10),制备Ⅴ类洞.第1组为激光预备加37％磷酸处理组,第2组为激光预备加FL-BOND处理组,第3组为激光预备加17％EDTA处理组.经冷热循环染色后,采用染料渗入法和扫描电镜方法观察充填体微渗漏情况,采用SPSS11.0软件包对数据进行统计学处理.结果:骀壁处染料渗入结果显示,第2组的染料渗入评分最小,与其余2组有显著差异(P＜0.05),第1组与第3组无显著差异.扫描电镜观察显示,第2组与第3组的边缘微缝隙宽度有显著差异(P＜0.05),其余各组间无显著差异,此结果与染料渗入法的结果不完全一致.龈壁处,3组染料渗入评分及充填体边缘微缝隙宽度均无显著差异,仅第2组(牙合)壁与龈壁的染料渗入评分及边缘微缝隙宽度有显著差异(P＜0.05).结论:自酸蚀黏结剂可有效减少复合树脂与Er,Cr∶YSGG激光制备的Ⅴ类洞(牙合)壁间微渗漏;在全酸蚀黏结剂及应用EDTA处理剂的条件下,复合树脂与Er,Cr∶YSGG激光制备的窝洞壁间微渗漏无差异.     

复合树脂与Er,Cr:YSGG激光制备的窝洞壁间微渗漏评价

目的:研究复合树脂与Er,Cr:YSGG(掺铒铬钇钪镓石榴石)激光制备的窝洞壁间微渗漏。方法:将30颗离体前磨牙随机分为3组(n=10),制备V类洞。第1组为激光预备加37%磷酸处理组,第2组为激光预备加FL-BOND处理组,第3组为激光预备加17%EDTA处理组。经冷热循环染色后,采用染料渗入法和扫描电镜方法观察充填体微渗漏情况,采用SPSS11.0软件包对数据进行统计学处理。结果:壁处染料渗入结果显示,第2组的染料渗入评分最小,与其余2组有显著差异(P<0.05),第1组与第3组无显著差异。扫描电镜观察显示,第2组与第3组的边缘微缝隙宽度有显著差异(P<0.05),其余各组间无显著差异,此结果与染料渗入法的结果不完全一致。龈壁处,3组染料渗入评分及充填体边缘微缝隙宽度均无显著差异,仅第2组壁与龈壁的染料渗入评分及边缘微缝隙宽度有显著差异(P<0.05)。结论:自酸蚀黏结剂可有效减少复合树脂与Er,Cr:YSGG激光制备的V类洞壁间微渗漏;在全酸蚀黏结剂及应用EDTA处理剂的条件下,复合树脂与Er,Cr:YSGG激光制备的窝洞壁间微渗漏无差异。     

饵激光预备及光固化灯超强功率模式对树脂微渗漏的影响

目的研究饵激光备洞和光固化灯超强功率模式对树脂充填微渗漏的影响。方法将40颗离体后牙随机平均分成4组进行备洞和充填固化。A组:高速涡轮机加安福士椅旁LED灯(550 m W/cm2,20 s);B组:高速涡轮机加VALO光固化灯(超强功率模式3 200 m W/cm2,3 s);C组:铒激光加安福士椅旁LED灯;D组:铒激光加VALO光固化灯。所有样本制备V类洞并行树脂充填后置于37℃生理盐水中24 h,冷热循环后亚甲基蓝溶液染色,在低速切割机下颊舌向切开,体式显微镜下观察剖面微渗漏情况,计分,统计。结果所有样本的龈壁微渗漏与牙合壁相比较更高,A组微渗漏程度较B、C组低,有统计学差异(P<0.05)。D组微渗漏最大,与其他各组有统计学差异(P<0.05)。结论铒激光备洞和光固化灯超级功率模式都会增加树脂充填微渗漏的发生。     

Microleakage of class V resin composite restorations after conventional and Er:YAG laser preparation

This in vitro study compared the microleakage of Class V resin composite restorations at bevelled enamel/composite and dentin/composite interfaces following Er:YAG laser (pre-treatment modalities: laser-etching and/or acid-etching) or conventional preparation and acid-etch, in association with two resin composite formulations and their three-step adhesive system. Class V cavities with conventional bevel produced on the lingual and buccal surfaces of eighty extracted caries- and restoration-free human teeth, were assigned to eight groups: cavities were or Er:YAG-lased and acid-etched (groups 1 and 5); or Er:YAG-lased, laser-etched and acid-etched (groups 2 and 6); or Er:YAG-lased and only laser-etched (groups 3 and 7); or cut by dental drill at high-speed and acid-etched (groups 4 and 8). The specimens were restored with Optibond FL+Herculite XRV (groups 1, 2, 3 and 4) or with Scotchbond MP+Z 100 (groups 5, 6, 7 and 8), stored in distilled water at 37 degrees C for 24 h, thermocycled 1500 times between 5 and 55 degrees C, placed in a 2% aqueous solution of methylene blue for 24 h at 37 degrees C, embedded in resin and sectioned. Microleakage was assessed according to the depth of dye penetration along the restoration. There were statistically significant differences between occlusal and cervical regions for all groups (P<0.01) except for groups 3 and 7. Pair-wise comparison of groups showed that acid-etch is advocated when using resin composite in Er:YAG-lased Class V cavities; the seal at enamel margins in Er:YAG-lased and laser-etched cavities depended on the resin composite formulation and corresponding adhesive (P<0.05).     

Assessing microleakage of different class V restorations after Er:YAG laser and bur preparation

This study assessed in vitro marginal leakage of class V cavities prepared by turbine and Er:YAG laser and restored with different materials. Sixty cavities with enamel and dentine margins were prepared and assigned to six groups: I, II, III by turbine and IV, V, VI by Er:YAG laser. The following restorative systems were used: groups I and IV: Bond 1 + Alert; II and V: Fuji II LC; III and VI: SBMP + Dispersalloy. After finishing, specimens were thermocycled for 8 h and 45 min (500 cycles), isolated, immersed in a 0.2% Rhodamine B solution, sectioned oro-facially and analysed for leakage. The dye penetration means (%) were: occlusal I: 10.09 (+/- 21.28), II: 3.25 (+/- 10.27), III: 0, IV: 41.77 (+/- 42.48), V: 23.37 (+/- 33.79), VI: 12.66 (+/- 24.06); cervical I: 16.49 (+/- 26.67), II: 4.34 (+/- 13.71), III: 0, IV: 37.71 (+/- 30.47), V: 39.56 (+/- 43.35) and VI: 72.53 (+/- 37.79). The use of Er:YAG laser for cavity preparation yielded higher degree of marginal leakage, as compared with the use of conventional air-turbine. The enamel interface provided better marginal sealing, comparing with dentine/cementum margin. As to the cavity preparation device (i.e. laser or bur), the analysis of the results showed that bonded amalgam and Fuji II LC provided less infiltration, than Alert. On the other hand, for lased cavities, Alert provided the best results, similar to those of Fuji II LC and superior to those reached by bonded amalgam.     

Er：YAG激光在龈下楔状缺损治疗中的临床应用

目的评价Er：YAG激光在治疗龈下楔状缺损中的应用。方法选择有两个洞缘位于龈下1mm～2mm的楔状缺损患牙的患者共20例。对照组以车针预备窝洞,电刀切除牙龈的方法进行牙体预备,实验组以Er：YAG激光预备窝洞并同时切除牙龈的方法完成预备。以VAS评分记录术中不舒适程度,术后随访12个月检查充填体情况。结果试验组VAS平均值为42.3±12.1,对照组VAS平均值为61.1±17.0,两组间差异有显著性（P〈0.01）。术后1周,对照组有1例发生龈退缩。12个月,试验组和对照组分别有2例和3例出现边缘不密合和边缘着色（P〉0.05）。结论激光行龈下楔状缺损牙体预备的方法可以有效减轻术中不适,对充填体质量无副作用。     

Immunohistochemical study on pulpal response in rat molars after cavity preparation by Er:YAG laser

While Er:YAG laser systems are in extensive use for caries removal and cavity preparation, the effects of such treatment on pulp tissue remain unclear. This study evaluates these systems using immunohistochemical methods and compares the results with information gained from treatment using conventional burs. Cervical cavities were prepared in the upper first molars of rats, using either an Er:YAG laser or a conventional tungsten-carbide bur. At intervals of 5 min, 6 h, 12 h, 1 d, 3 d and 7 d after cavity preparation, the teeth were processed for immunohistochemical analyses of tissue non-specific alkaline phosphatase, OX6-positive major histocompatibility complex class II antigen-expressing cells and PGP 9.5-immunoreactive nerve fibers. DNA fragmentation was detected by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) method. Tissue non-specific alkaline phosphatase was observed mainly in the subodontoblastic layer under the cavity lesion, from 5 min, in both groups. The immunoreactivity was more pronounced in the laser group, but by 7 d no significant differences were recognizable. At 12 h, TUNEL-positive cells were detected around the odontoblastic layer in both groups. From 3 d to 7 d, a limited number of positive cells were still visible in the group that underwent standard treatment. Clear similarities in the distribution patterns of OX6-immunopositive cells and PGP 9.5-immunoreactive nerve fibers were also noted. From 12 h to 1 d, OX6-positive cells accumulated along the pulp-dentin border, extending their processes into the dentinal tubules. Numerous bead-like PGP 9.5-immunoreactive nerve fibers were observed under the odontoblastic layer at 7 d. These results demonstrated that there was no appreciable difference in the manner in which pulp tissue responded to treatment with either Er:YAG laser or a conventional drill. This would seem to indicate the usefulness of the Er:YAG laser system in the removal of caries and cavity preparation.