Er,Cr:YSGG激光制备对牙体抗剪切强度影响的实验研究

目的　比较Er,Cr:YSGG激光与传统高速手机两种切割方法对牙体抗剪切强度的影响 ,分析Er,Cr:YSGG激光是否可以提高牙面的黏结强度。方法　选取新鲜离体牛上中切牙 4 6颗 ,分为两组 ,分别采用Er,Cr :YSGG激光和高速手机切割牙体。通过分组对照 ,进行抗剪切强度实验、扫描电镜观察、能谱分析及X线衍射分析。结果　Er,Cr:YSGG激光组的抗剪切强度高于高速手机组 (P <0 .0 0 1) .扫描电镜下观察 ,激光组的牙体表面清洁、粗糙 ,无玷污层存在 ,牙本质小管口开放 ,无裂化、熔融等热损伤迹象 ;能谱分析与X线衍射分析结果表明 ,两组样本在表面成分、结构上无明显差异。结论　Er,Cr:YSGG激光制备牙体不会引起牙体组织成分及结构的改变 ;Er,Cr:YSGG激光制备后的牙体抗剪切强度高于高速手机制备后的牙体 ,Er,Cr:YSGG激光制备牙体可以提高牙体的黏接强度。     

Er.Cr.YSGG激光在龋病治疗中的应用研究

Er．Cr．YSGG激光是新一代水动力生物激光系统,在龋病治疗中的应用正不断深入。本文对其去除龋坏牙体组织的能力、原理,清除玷污层和蚀刻牙体硬组织能力及应用的安全性进行综述。     

Er��Cr��YSGG����������������벣������ˮ��͡�俹������ǿ��Ӱ����о�

目的评价Er,Cr:YSGG激光照射对牙本质与玻璃离子水门汀间抗剪切黏结强度的影响。方法于2008年7月至12月,在中国医科大学口腔医院收集15颗因正畸拔除的无龋坏、无隐裂的完整离体前磨牙。将标本牙的颊侧与舌侧牙本质表面分别用Er,Cr:YSGG激光照射处理(实验组)和涡轮手机处理(对照组),经FX-Ⅱ玻璃离子水门汀充填及冷热循环后进行剪切力实验,计算标本牙的抗剪切黏结强度,体视显微镜下观察牙体组织的剪切断面。结果剪切力实验结果显示:实验组牙本质与充填材料间的抗剪切黏结强度显著高于对照组(P<0.05)。体视显微镜观察:实验组牙体组织的剪切断面凹凸不平,充填物残留更多;对照组则较光滑、平坦。结论Er,Cr:YSGG激光照射会增强牙本质与玻璃离子水门汀间的抗剪切黏结强度。     

Er,Cr:YSGG激光照射后牙周病牙根面的形态学研究和钙磷比率分析

目的 观察Er,Cr:YSGG激光照射后牙周病牙根面的形态学变化及主要元素钙、磷的改变。方法 收集中、老年人离体牙周病牙18颗、健康阻生第三磨牙6颗。对18颗牙周 病患牙根面进行平整后,随机选取12颗作激光照射研究;其余6颗作酸处理研究;6颗第三磨牙作健康对照。扫描电镜下观察不同根面处理方式导致的根面形态变化,用色谱分析仪分析各组根面钙磷比率（Ca/P）,并进行统计学比较。结果 激光照射组可有效去除玷污层,得到粗糙度较均匀、洁净的根面。酸处理组去除根面玷污层能力较强,但电镜观察两组根面形态有差异。两组均未发现熔融、炭化、裂纹及牙本质暴露。色谱分析仪分析结果显示激光照射组与酸处理组根面钙磷比率无明显差异（P>0.05）。结论 Er,Cr:YSGG激光照射根面平整后的牙周病牙根面可有效去除玷污层及表层病变牙骨质,具有潜在的应用 价值。     

Er,Cr:YSGG激光和酸蚀处理牙本质表面后的扫描电镜观察

目的 本文通过电镜观察，研究不同预备方法处理牙本质后表面形态的改变及树脂-牙本质界面形态的差别。方法 用10颗拔除的第三磨牙制作牙本质片，每个牙本质片预备三个窝洞，分别用传统方法加酸蚀预备，Er，Cr：YSGG激光预备及激光加酸蚀预备。将10个牙本质片分为A、B两组，A组在电镜下观察牙本质表面形态改变；B组用流动树脂充填，暴露树脂-牙本质界面，样本经处理后在电镜下观察比较。结果 A组：传统方法预备后牙本质表面可见开放的牙本质小管口；激光预备后开放的牙本质小管口呈现火山口样；激光加酸蚀处理后的牙本质小管周围呈现白晕。B组：传统预备方法的树脂一牙本质界面可见混合层，圆锥型树脂突和侧枝连接的形成；单纯激光预备后界面没有混合层的形成，形成的树脂突呈圆柱型，较长并且细密；激光加酸蚀处理后界面可见少量混合层形成，树脂突圆柱型，粗、长且有少量侧枝连接。结论 Er，Cr：YSGG激光加酸蚀处理后，开放的牙本质小管周围可见来完全脱矿的管周牙本质．树脂一牙本质界面可见混合层和粗长的圆柱形树脂突。     

Effects of dentin surface treatments including Er,Cr:YSGG laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin

Abstract

Objective. Intra-canal post systems are commonly used to restore root-filled teeth. Bond strengths of the posts can be affected by various surface treatments of the post or the dentin. The aim of this study was to evaluate the effects of dentin surface treatments including erbium-chromium; yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser irradiation with different intensities on the push-out bond strength of the glass fiber posts to root dentin. Materials and methods. Forty single-rooted human maxillary incisors were filled and post spaces were prepared. After these procedures, the specimens were divided randomly into four groups according to the dentin surface treatments, as follows: (i) untreated surface (control), (ii) 1W Er,Cr:YSGG laser application, (iii) 2W Er,Cr:YSGG laser application and (iv) 3W Er,Cr:YSGG laser application. Then the posts were cemented into the root canals using dual-cured resin cement. Bonded specimens were cut into 1-mm-thick slices and push-out tests were performed using a universal testing device. All specimens were loaded until fracture and the failure modes were evaluated with a stereomicroscope at 32× magnification. Representative specimens were analyzed by scanning electron microscopy. Data were analyzed using a one-way ANOVA, Tukey and Wilcoxon tests. Results. The bond strength values ranged from 3.22–4.68 MPa. There were no statistically significant differences among the groups, regardless of the different levels. The coronal and middle levels of the post space had significantly higher bond strength values compared with the apical level (p < 0.05). Conclusion. Er,Cr:YSGG laser irradiation with different intensities did not increase the bond strength of the fiber posts to the root canal dentin walls.     

Er,Cr:YSGG激光照射对窝沟封闭剂粘结性的影响

目的 :探讨Er,Cr:YSGG激光照射作为窝沟封闭前釉质预处理方式的可能性。方法 :以 40颗离体前磨牙做为标本 ,随机分成 4组 ,唇面釉质分别采用下列方式处理 ,A组 :杯状刷处理 酸蚀 ,B组 :钻切割 酸蚀。C组 :Er ,Cr :YSGG激光照射 ,D组 :Er,Cr :YSGG激光照射 酸蚀。测试窝沟封闭剂与釉质面的抗剪强度 ,并用扫描电镜观察 4种方式处理后釉质表面的形态特征。结果 :Er ,Cr :YSGG激光照射与传统杯状刷或钻处理后酸蚀的釉质面抗剪强度相似无显著性差异 (P >0 .0 5 ) ,Er ,Cr:YSGG激光照射后酸蚀也不增大抗剪强度。SEM观察Er ,Cr :YSGG激光照射后的釉质面不规则 ,鱼鳞状 ,无玷污层。结论 :Er ,Cr :YSGG激光照射可代替传统杯状刷或钻处理后酸蚀 ,是一种较好的窝沟封闭前预处理方式     

The effect of Er,Cr:YSGG laser and air abrasion on shear bond strength of a fissure sealant to enamel

PurposeThe authors conducted an in vitro study to evaluate the shear bond strength of a fissure sealant to enamel pretreated with erbium, chromium: yttrium, scandium, gallium, garnet (Er, Cr: YSGG) laser or air abrasion followed by acid etching.MethodsThe authors sectioned extracted sound premolars mesiodistally and used the buccal and lingual surfaces for experimental analysis. They divided specimens randomly into three groups of 15 each according to the enamel surface pretreatment methods: group A, 37 percent phosphoric acid; group B, air abrasion followed by acid etching with 37 percent phosphoric acid; group C, irradiation with Er, Cr: YSGG laser followed by acid etching with 37 percent phosphoric acid. After applying a bonding system, the authors bonded cylinders of sealant to the enamel surfaces by using transparent gelatin tubes (0.7 millimeter in diameter and 1 mm in height) and then polymerized them. They stored all specimens in distilled water at 37°C for 24 hours. They tested shear bond strength by using a universal testing machine with a crosshead speed of 0.5 mm per second. The authors analyzed the data by means of one-way analysis of variance and Tukey-Kramer post hoc tests (α = .05).ResultsThe bond strength of group B specimens was statistically higher than those of group A and group C specimens (P < .05). The authors found no statistically significant differences in shear bond strength between surfaces treated with Er, Cr: YSGG laser and those treated with acid etching alone (P > .05).ConclusionPretreatment of enamel surfaces with air abrasion increased the bond strength of fissure sealant, but pretreatment with Er, Cr: YSGG laser did not increase the effectiveness of conventional acid etching of enamel in sealant bonds.     

Er,Cr:YSGG激光制备颊(舌)面近颈部洞对材料与洞壁密合性影响的研究

目的 :研究Er,Cr:YSGG激光制备前磨牙颊 (舌 )面近颈部洞对黏结材料与洞壁密合性的影响。方法 :选用 18个新近拔除的正畸减数牙 ,按以下方式进行分组处理 :①对照组 ,高速钻制洞 ,总体酸蚀剂酸蚀 2 0s。②Er ,Cr :YSGG激光制洞。③Er ,Cr :YSGG激光制洞后 ,总体酸蚀剂酸蚀 2 0s。通过体视显微镜观察染料渗透情况。结果 :①三组间牙合壁的染料渗透情况无统计学差异 (P >0 .0 5 )。②三组间颈壁的染料渗透情况无统计学差异 (P >0 .0 5 )。③各组内颈壁的染料渗透情况均比牙合壁明显 (P <0 .0 5 )。结论 :Er ,Cr:YSGG激光制洞不会减弱或提高黏结材料与洞壁的边缘密合性 ,可代替牙钻制洞后联合酸蚀。     

Comparison of periodontal open flap debridement versus closed debridement with Er,Cr:YSGG laser

Background

Traditional periodontal open flap debridement (OFD) results in reduced pocket depth (PD), clinical attachment loss (CAL), gingival recession (GR) and postoperative pain and discomfort. The quest to overcome these shortcomings has led to research into Er,Cr:YSGG laser assisted pocket therapy (ELAPT). This study was designed to compare the clinical outcomes of ELAPT versus OFD.

Methods

Fifteen patients with a PD of ≥5 mm and ≤8 mm at two sites were selected. Test sites (Group 1) were treated by ELAPT and the control (Group 2) by OFD. Clinical parameters were recorded at baseline, 3 and 6 months and included Plaque Index (PI), Gingival Index (GI), modified Sulcular Bleeding Index (mSBI), PD, CAL and GR.

Results

Both treatments produced a reduction in PI, GI, mSBI and PD, an increase in GR, and a gain in CAL at 3 and 6 months. The mean gain of CAL in Group 1 at 3 and 6 months (1.60 ± 0.78 and 1.80 ± 0.63) was similar (p > 0.05) to the value of Group 2 (1.93 ± 0.88 and 2.00 ± 0.54). GR increased significantly (p < 0.05) only in Group 2 at 3 and 6 months (1.80 ± 0.56 and 1.87 ± 0.64) compared to Group 1 (0.50 ± 0.68 and 0.60 ± 0.74).

Conclusions

ELAPT compared with OFD results in similar CAL gains with less GR and significant reductions in PD, GI and mSBI, and may be considered as an alternative to surgical therapy.     

ErCr:YSGG激光对牙本质界面粘结强度及形态结构的影响

目的：研究ErCr:YSGG激光在不同粘结机理作用下对牙本质黏结剂黏结强度和微观形态的影响。方法：20颗完整无龋的人第三磨牙,去除咬合面釉质,随机分为4组 (n=5)：第1组：激光预备+全酸蚀粘结剂;第2组：常规预备+全酸蚀粘结剂;第3组：激光预备+自酸蚀粘结剂;第4组：常规预备+自酸蚀粘结剂。复合树脂粘结至牙面制成1.0mm*1.0mm*10mm长方体试样,微拉伸测试黏结强度并进行统计学分析。体视显微镜下观察断裂类型,每组随机选取2个断裂前样本及粘结前样本行扫描电镜观察。另4颗分为2组（n=2）分别做激光预备和常规预备后电镜观察粘结前界面。 结果：黏结强度第4组最低（12.37±3.12Mpa）,与其它3组有统计学差异（P<0.01）,其他3组间无统计学差异（P>0.05）;断裂类型多为黏结剂断裂的混合破坏,各组断裂类型间无统计学差异(P>0.05);扫描电镜观察第1-3组混合层薄而致密,树脂突长而粗,第4组混合层不均一,树脂突短而细。水激光预备样本的牙本质小管开放,牙本质表面清洁、无热损伤痕迹。常规预备样本的牙本质小管封闭,表面玷污层较厚。 结论：ErCr:YSGG激光可显著提高自酸蚀粘结剂的粘结强度。     

Er，Cr：YSGG激光在慢性牙周炎非手术治疗中的应用

目的：探讨超声龈下刮治结合Er,Cr：YSGG激光治疗慢性牙周炎的临床效果。方法纳入12名慢性牙周炎患者,超声龈上洁治后2周进行基线检查,采用分口设计,四个象限随机分组。实验组在超声龈下刮治的基础上,激光照射1次或3次;对照组在超声龈下刮治基础上进行手工根面平整。治疗结束后分别记录每象限治疗用时,患者对每象限治疗时的舒适程度视觉模拟评分。在基线、治疗后6周及12周检查牙周临床指标,包括菌斑指数、牙龈出血指数、探诊深度及临床附着丧失。结果实验组和对照组各项临床指标均有显著改善,且临床疗效相当。和传统手工根面平整术比较,激光照射治疗所需时间较长,舒适度更加;和激光照射1次比较,照射3次并无明显优势。结论超声龈下刮治结合Er,Cr：YSGG激光照射治疗慢性牙周炎的临床疗效良好,且激光照射在治疗过程中更为舒适,超声龈下刮治结合Er,Cr：YSGG激光照射1次可作为牙周炎非手术治疗可选方法之一。     

铒、铬:钇钪镓石榴石激光用于牙体窝洞制备的实验研究

目的 探讨铒、铬：钇钪镓石榴石激光在牙体窝洞制备的临床应用。方法 在中国小型猪牙齿上,采用铒、铬：钇钪镓石榴石激光制备窝洞，24小时后断头处死，拔除牙齿在光镜和扫描电镜下观察牙髓反应及洞形结构。结果 经铒、铬：钇钪镓石榴石激光制备窝洞后，偶见牙髓局部充血扩张，少许浆液渗出，无牙微裂及碳化形成，窝洞内无玷污层，切割表面利于粘接固位。结论 铒、铬：钇钪镓石榴石激光在窝洞制备方面有很好的临床使用价值。     

铒,铬:钇钪镓石榴石激光切割牙体硬组织效果的扫描电子显微镜观察

目的　对铒,铬:钇钪镓石榴石(Er,Cr:YSGG)激光切割的牙体硬组织进行扫描电子显微镜观察,探讨此激光在不同能量参数下进行窝洞制备的效果,以便为其在临床上的应用与推广提供实验依据。方法　将12颗前磨牙随机分3组,分别用高速裂钻、4W Er,Cr:YSGG激光及6W Er,Cr:YSGG激光处理后,将牙齿沿横向、纵向剖开,常规制片,扫描电镜观察牙体硬组织表面结构形态。结果　钻切组:切面较平,但有明显裂纹;表面覆盖致密的玷污层。激光组:切面不平,呈鱼鳞状改变,无玷污层;牙本质切面小管清晰,无炭化及热损伤改变。与4 W功率相比,6 W时表面更为粗糙。结论　应用Er,Cr:YSGG激光切割后的牙体,其表面结构有助于修复材料与牙体组织间的粘接。建议临床应用时采用高能量参数切割牙釉质,低能量参数切割牙本质。     

Microleakage of composite resin restorations in cervical cavities prepared by Er,Cr:YSGG laser radiation

BACKGROUND: Evaluation of microleakage is important for assessing the success of new methods for surface preparation and new adhesive restorative materials. The aim of this laboratory study was to assess microleakage at the margins of composite restorations in Er,Cr:YSGG laser prepared cavities on the cervical aspects of teeth by means of dye penetration, and compare this with conventionally prepared and conditioned cavities. METHODS: Class V cavities were produced on sound extracted human teeth, which had been assigned randomly to one of three groups (N = 10 each), as follows: Group 1 - prepared using a diamond cylindrical bur and then treated with 37% phosphoric acid; Group 2 - irradiated with an Er,Cr:YSGG laser (Biolase Waterlase) and then treated with 37% phosphoric acid; Group 3 - irradiated only with the laser. After application of bonding agent (Excite, Ivoclar Vivadent), all cavities were restored with composite resin (Heliomolar). After polishing the restorations, the teeth were thermocycled from 5-50 degrees C for 500 cycles. Dye leakage was assessed after immersion in methylene blue, by examining longitudinal sections in a stereomicroscope at x 30 magnification. RESULTS: The extent of dye penetration was lowest in the laser only group (Group 3). Penetration of dye to dentine and axial walls occurred in 80 per cent of conventionally prepared (bur + acid) specimens, but in the laser group, dye penetration to the axial wall occurred in only 30 per cent of cases. There was a strong statistical association between treatment group and the distribution of microleakage scores (Chi-square, P = 0.0023). CONCLUSIONS: For Class V cavities, with the adhesive materials employed, higher microleakage occurs with phosphoric acid etching of bur- or laser-cut surfaces, than with the surface created by use of the laser alone without additional conditioning.     

Effect of an Er,Cr:YSGG laser on water perfusion in human dentine

Adu‐Arko AY, Sidhu SK, McCabe JF, Pashley DH. Effect of an Er,Cr:YSGG laser on water perfusion in human dentine.
Eur J Oral Sci 2010; 118: 483–488. © 2010 Eur J Oral Sci Changes in fluid perfusion through tubules may affect the sensitivity of exposed and restored dentine. The rate of perfusion is dependent on the structure and composition of dentine, particularly at the surface. This work analyzed the effect of treatment with an Erbium, Chromium‐doped: Yttrium Scandium Gallium Garnet (Er,Cr:YSGG) laser on dentine perfusion. Extracted molars were sectioned above the mid‐coronal portion, and below the cemento–enamel junction, to create crown segments. The pulp was extirpated and the dentine treated with the Er,Cr:YSGG laser, a diamond bur or sandpaper. Each specimen was mounted, with the pulp chamber oriented upwards, on a petri‐dish cover in order to permit a tube filled with water to be connected to the pulp. Movement of the water meniscus over 24 h provided a measurement of the volume of water that filtered across the dentine. The dishes contained water to provide a moist environment in the relevant specimens, or were left dry to provide dry conditions. Specimens were perfused for 24 h with water pressures ranging from 20 to 60 cm. The results (in μl mm^?2 d^?1) showed a significant difference in the perfusion rate between treatments. The difference between perfusion in wet and dry conditions was highly significant. Laser and bur treatment of dentine significantly affected perfusion, which was higher in the former than in the latter. Therefore, laser‐treated dentine may be more sensitive than bur‐cut dentine.     

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。     

Push‐out bond strength of two root‐end filling materials in root‐end cavities prepared by Er,Cr:YSGG laser or ultrasonic technique

This study compared the push‐out bond strength of mineral trioxide aggregate (MTA) and a new endodontic cement (NEC) as root‐end filling materials in root‐end cavities prepared by ultrasonic technique (US) or Er,Cr:YSGG laser (L). Eighty single‐rooted extracted human teeth were endodontically treated, apicectomised and randomly divided into four following groups (n = 20): US/MTA, US/NEC, L/MTA and L/NEC. In US/MTA and US/NEC groups, root‐end cavities were prepared with ultrasonic retrotip and filled with MTA and NEC, respectively. In L/MTA and L/NEC groups, root‐end cavities were prepared using Er,Cr:YSGG laser and filled with MTA and NEC, respectively. Each root was cut apically to create a 2 mm‐thick root slice for measurement of bond strength using a universal testing machine. Then, all slices were examined to determine the mode of bond failure. Data were analysed using two‐way anova . Root‐end filling materials showed significantly higher bond strength in root‐end cavities prepared using ultrasonic technique (US/MTA and US/NEC) (P < 0.001). The bond strengths of MTA and NEC did not differ significantly. The failure modes were mainly adhesive for MTA, but cohesive for NEC. In conclusion, bond strengths of MTA and NEC to root‐end cavities were comparable and higher in ultrasonically prepared cavities.     

Er、Cr:YSGG激光根管内照射对根管封闭效果的影响

目的:探讨常规根管预备后使用不同能量的Er、Cr:YSGG激光进行根管内照射对根充后根管封闭效果的影响。方法:选择新拔除的单根管牙105颗,分成7组,每组15颗牙。切除牙冠后,常规进行根管预备。第1组不进行任何处理,作为阳性对照组;第2组为1W、有水激光照射;第3组为1W、无水激光照射;第4组为2W、有水激光照射;第5组为2W、无水激光照射;第6组为3W、有水激光照射;第7组为3W、无水激光照射。根充后进行根尖微渗漏检测,评估根管封闭效果。采用单因素方差分析(Anova)进行多组间总体均数比较,q检验进行组间比较。结果:除3W无水组外,其他各激光组与对照组相比,根尖微渗漏深度均有显著性差异(P<0.05);其中1W无水组与对照组相比具有高度显著性差异(P<0.01)。结论:较低能量(除外3W、无水)Er、Cr:YSGG激光进行根管内照射,能够有效提高根管充填后的封闭效果,其中1W、无水激光照射时根管封闭效果最好。     

Er,Cr:YSGG激光对乳牙硬组织粘接性能影响的研究进展

Er,Cr:YSGG激光以其能够安全、精确地切割牙体硬组织而成为近年来激光牙科学的研究热点.Er,Cr:YSGG激光照射后牙体硬组织的表面形态、成分及结构均发生改变,这些变化对后续修复材料粘接力的影响目前还存在争议.本文从Er,Cr:YSGG激光用于牙体硬组织切割的机制、乳牙组织的结构特点、Er,Cr:YSGG激光处理对乳牙牙体硬组织粘接力的影响、Er,Cr:YSGG激光在儿童口腔领域应用的安全性、优势及展望做一综述.