Er∶ YAG激光光子增强的光声流效应技术清理根管玷污层效果的体外研究

目的 观察不同Er∶YAG激光技术对根管内壁玷污层的清理能力,探究光子增强的光声流效应(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术对根管内壁玷污层的清理效果.方法 示波器精确测定Er∶ YAG激光不同工作模式的脉冲波形.收集人离体第三磨牙...     

Er: YAG激光PIPS/SWEEPS去除复杂根管内氢氧化钙的效果研究

目的:评价两种Er:YAG激光活化冲洗技术光子引导光声流(photon-initiated photoacoustic streaming, PIPS)和光波增强光声流(shock wave enhanced emission photoacoustic streaming, SWEEPS)去除复杂根管内氢氧化钙的效果。方法:选取75颗人新鲜拔除单根管前磨牙,WaveOne Gold Primary根备后纵向劈开,在2个半片牙根尖段分别制备凹沟和半球,根管注满氢氧化钙。样本随机分为5组,分别应用PIPS、SWEEPS、EDDY、被动超声冲洗(passive ultrasonic irrigation, PUI)和传统注射器冲洗(conventional needle irrigation, CNI)去除根管内氢氧化钙。冲洗前后显微镜下拍照,计算残余氢氧化钙面积百分比,不规则区(凹沟与半球)采用计分法评价去除效果。结果:氢氧化钙整体去除率由高到低依次为：SWEEPS、PIPS、EDDY/PUI、CNI,EDDY与PUI无明显差异(P>0.05);不规则区：SWEEPS最佳,PIPS...     

Er:YAG激光辅助根管荡洗对冲洗液根尖溢出影响的系统评价

目的 系统评价掺铒钇铝石榴石(Er:YAG)激光辅助根管荡洗光子引导光声流(PIPS)技术及相关因素对冲洗液根尖溢出的影响。方法 系统检索Pubmed、Scopus、Embase、Web of Science、中国期刊全文数据库(CNKI)、维普中文期刊服务平台(VIP Database)及万方数据库(Wanfang Database)中PIPS技术导致冲洗液根尖溢出安全性的中英文文献,检索时限为2007年1月至2022年5月。两名研究者筛选文献、提取信息、质量评价后进行描述性分析。结果 最终纳入7篇文献,结果显示,相比临床注射流速下的注射器冲洗,较低功率的PIPS技术未产生更多的冲洗液根尖溢出量,根管预备尺寸不是PIPS技术产生根尖溢出量的影响因素。结论 当前证据显示,Er:YAG激光辅助根管荡洗较传统注射器冲洗产生冲洗液根尖溢出的风险更小。受纳入研究数量和质量限制,上述结论尚需开展更多高质量研究予以验证。     

Er:YAG激光照射对牙本质粘结强度的影响

目的探讨Er:YAG激光照射对牙本质粘结强度的影响。方法选取离体磨牙或前磨牙40颗,随机分为4组:A:酸蚀(35%磷酸)组;B:Er:YAG激光组;C:Er:YAG激光+磷酸酸蚀组;D:空白对照组。每组随机选取2颗制备成3 mm厚的牙本质盘,相应预处理后扫描电镜观察;每组剩余8颗牙制备统一标准粘结面,相应预处理后与树脂粘结测量剪切粘结强度。结果扫描电镜结果显示牙本质面经相应预处理后发生明显改变;统计分析结果显示A组剪切粘结强度最大(16.03±6.56)MPa,其次为C组(13.21±6.08)MPa,两组间差异无统计学意义(P>0.05);D组剪切粘结强度最低(4.52±1.02)MPa,与B组(7.91±4.56)MPa比较差异无统计学意义(P>0.05),与A、C组比较差异有统计学意义(P<0.05)。结论 Er:YAG激光照射联合磷酸酸蚀较单纯Er:YAG激光照射可提高牙本质剪切粘结强度。     

Er:YAG激光预处理对牙本质-全瓷粘结剪切强度影响的体外研究

目的研究Er:YAG激光预处理牙本质对牙本质与全瓷粘结剪切强度的影响,以期为Er:YAG激光在临床的应用提供参考。方法选择新鲜拔除的完整第三磨牙80颗,根据表面处理方法不同随机分为5组,每组颊面标记为ABCDE,舌面标记为abcde。A/a:Er:YAG激光光照+Optibond Versa/Adper Easy One组;B/b:Er:YAG激光光照+35%磷酸酸蚀+Optibond Solo Plus/Adper Single Bond 2组;C/c:Er:YAG光照能量密度15.73 J/cm~2/31.46 J/cm~2组;D/d:Optibond Versa/Adper Easy One粘结剂组;E/e:35%磷酸酸蚀+Optibond Solo Plus/Adper Single Bond 2组。计算机设计制作牙制作直径3 mm厚2 mm IPS e.max PressⅡ瓷块,常规粘结后制作剪切试件并测剪切粘结强度,电子显微镜下观察断裂类型。SPSS20.0统计学分析软件分别对实验数据进行单因素方差分析和χ~2检验,对实验数据进行两两比较。结果 Er:YAG激光光照与全酸蚀粘结剂联合组剪切强度(23.01±4.41/25.37±3.96)MPa,显著高于其他组,差异有统计学意义(P<0.05)。结论不同厂家的全酸蚀粘结剂联合Er:YAG激光预处理牙面均能够有效提高牙本质与全瓷的粘接强度。     

脉冲Nd:YAG激光不同条件下照射牙根管壁的形态学观察

目的 :观察不同条件下脉冲Nd :YAG激光照射牙根管壁后的清洁程度及管壁牙本质的超微结构改变。方法 :14颗离体人上前牙 ,常规根管预备后 ,分为对照组和激光照射组 ,后者按不同的功率、频率及管壁加墨汁与否 6种设定各 2颗牙分别进行照射 ,然后各组标本扫描电镜下观察并照像记录。结果 :①激光照射各组均较对照组根管壁玷污层减少 ;且随激光功率增大 ,管壁清洁度提高 ,管壁牙本质的超微结构变化增大。其中 2W 2 0 pps组管壁上无玷污层 ,根尖 1/ 3区尚有牙本质熔融、沉积。 3W 2 0pps、4W 2 0 pps组除上述变化外 ,根管壁牙本质熔融更为显著 ,并有程度不同的炭化和裂缝 ;② 2W 15 pps管壁清洁度较 2W 2 0pps组低 ;③ 1W 2 0 pps加墨汁后 ,根管清洁效果显著改善 ,并出现牙本质熔融、小管口封闭。结论 :激光剂量在 2W 2 0pps或在此以上时能有效去除根管壁玷污层 ,达到较理想的清洁效果 ,但只有较大剂量时才能熔融、封闭牙本质小管口 ;加墨汁能在低能量条件下显著增强激光作用效果。     

Er:YAG激光对牙本质与通用粘接剂粘接界面特征的影响

目的:观察Er:YAG激光预处理的牙本质与通用粘接剂在自酸蚀和酸蚀-冲洗使用模式下粘接界面的超微结构特征,并与未处理的牙本质粘接界面进行对比,以探索二者之间粘接机制的差异.方法:选取36颗完整的人类第三磨牙,按照表面预处理方式和通用粘接剂的使用模式随机分为4组(A组:空白对照+自酸蚀;B组:空白对照+酸蚀-冲洗(35％...     

不同脉冲宽度Er:YAG激光激活根管荡洗的研究

目的:探究Er:YAG激光的不同脉冲宽度模式对激光在前牙单根管树脂模型内形成的空泡动力及热沉积效应的影响。方法:示波器精确测定Er:YAG激光不同脉冲宽度模式的脉冲波形。在单根管树脂模型中,应用Er:YAG激光不同脉冲宽度模式进行激光激活荡洗.高速摄像机对激活荡洗形成的空泡进行摄录,并对图像进行分析,计算空泡直径、空泡体积、膨胀周期、塌缩周期和总周期。热电偶测量根管模型内髓腔液体温度变化,SPSS 19.0进行统计分析。结果:Er:YAG激光呈现驰豫振荡的固体激光特性。不同脉冲宽度模式下,首个脉冲峰宽度存在显著差异,空泡直径、空泡体积、塌缩周期和振荡周期随脉宽的增大而减小(P<0.05),髓腔液体温度随脉宽增大而增加(P<0.05)。结论:Er:YAG激光激活荡洗过程中,脉宽越窄,激光输出的首个脉冲峰宽度越小,空泡体积越大,髓腔内液体升温越低。窄脉宽Er:YAG激光模式可能更有利于激光激活荡洗。     

Er:YAG激光桩道预处理的研究进展

本文回顾了Er:YAG激光活化根管冲洗技术的最新研究进展,包括光子诱导光声流(photon initiated photoacoustic streaming,PIPS)技术和冲击波增强发射光声流(shock wave enhanced emission photoacoustic streaming,SWEEPS)技术,探讨Er:YAG激光预处理桩道的原理、优点以及对纤维桩粘接强度的影响,以期为临床选择适宜的桩道处理方法提供新思路。     

Nd:YAG激光和Er:YAG激光对根管内粪肠球菌杀灭效果的研究

［摘要］ 目的 观察Nd:YAG激光、Er:YAG激光及两者联用对根管内粪肠球菌的杀灭效果。方法 选取离体牙建立粪肠球菌感染模型,随机分为五组：A组：生理盐水组;B组：1%次氯酸钠溶液组;C组：Nd:YAG激光组;D组：Er:YAG激光组;E组：Nd:YAG激光+Er:YAG激光组。通过细菌培养和扫描电镜观察对比各组的杀菌效果。结果 细菌培养和扫描电镜结果显示：A组杀菌率最低,B组杀菌率最高,E组次高。除C组和D组间杀菌率相近外（P>0.05）,各组间均有统计学差异（P<0.05）。结论 Nd:YAG激光和Er:YAG激光均有一定的根管杀菌效果,两者联用效果更佳,可作为传统消毒方法的补充。     

������մɱ�����ɰ�������ʱ���Er��YAG���⴦�����֬��ǿ��Ӱ���о�

目的探讨氧化锆陶瓷表面不同粒径Al2O3颗粒喷砂及牙本质表面Er：YAG激光处理对树脂黏结强度的影响。方法2011年2—10月在山西医科大学口腔医院选取25颗完整人前磨牙,制作50个牙块,暴露牙本质。其中10个牙块表面用35％磷酸酸蚀处理,40个牙块表面用Er：YAG激光蚀刻处理。制作氧化锆陶瓷片50个,20个不做处理,其余30个（每组10个）在0．4MPa压力下分别接受120、80、40μm粒径Al2O3颗粒喷砂20s。试件分为5组（每组10个）：A、B组分别由35％磷酸酸蚀和Er：YAG激光蚀刻的牙块与未做处理的陶瓷片黏结;C、D和E组分别由120、80、40μm粒径Al2O3颗粒喷砂的陶瓷片与Er：YAG激光蚀刻的牙块黏结。各组分别进行黏结强度测试？结果A组的黏结强度[（8．71±0．86）MPa]低于B组[（10．94±0．93）MPa],两组差异有统计学意义（P〈0．05）;C、D和E组的黏结强度[（13．49±1．53）、（13．97±0．83）、（17．11±1．51）MPa]均高于B组,差异有统计学意义（P〈0．01）;C、D组的黏结强度低于E组,差异有统计学意义（P〈0．01）;但C与D组间差异无统计学意义（P〉0．05）。结论氧化锆陶瓷片表面Al2O3颗粒喷砂和牙本质表面Er：YAG激光蚀刻处理可增加氧化锆陶瓷与牙本质间的树脂黏结强度。     

Effect of Er:YAG laser treatment on the root canal walls of human teeth: an SEM study

Abstract— The purposes of the study were to observe the morphological changes on root canal walls after instrumentation and irrigation, and assess the efficacy of conventional cleansing procedures and the effectiveness of Er:YAG laser in removing debris and smear layer from the root canal walls. Thirty-six endodontically treated human mandibular incisor teeth with single root canals were bisected longitudinally and divided into three groups of 12 teeth. Group 1 (Gl) was left unlased as a control. The teeth of group 2 (G2) and group 3 (G3) were irradiated by Er:YAG laser (laser parameters were set at 1 W, 100 mJ/pulse and 10 Hz) for 3 s and 5 s. The teeth were prepared for scanning electron microscope study. Control specimens showed debris and heavy smear layer obscuring the dentinal tubules at all levels in the canals. The root canal walls irradiated by Er:YAG laser were free of debris, with an evaporated smear layer and open dentinal tubules. These results suggested that Er:YAG laser irradiation had an efficient cleaning effect on the prepared root canal walls.     

Visualization of irrigant flow and cavitation induced by Er:YAG laser within a root canal model

Introduction

Laser-activated irrigation (LAI) has recently been introduced as an innovative method for root canal irrigation. However, there is limited information about the cleaning mechanism of an Er:YAG laser. In this study, we visualized the action of laser-induced bubbles and fluid flow in vitro to better understand the physical mechanisms underlying LAI.

Methods

An Er:YAG laser was equipped with a novel cone-shaped tip with a lateral emission rate of approximately 80%. Laser light was emitted at a pulse energy of 30, 50, or 70 mJ (output energy: 11, 18, or 26 mJ) and a repetition rate of 1 or 20 pulses per second, without air or water spray. Fluid flow dynamics in a root canal model were observed by using glass-bead tracers under a high-speed camera. Moreover, laser-induced bubble patterns were visualized in both free water and the root canal model.

Results

Tracers revealed high-speed motion of the fluid. A full cycle of expansion and implosion of vapor and secondary cavitation bubbles were clearly observed. In free water, the vapor bubble expanded for 220 microseconds, and its shape resembled that of an apple. In the root canal model, the vapor bubble expanded in a vertical direction along the canal wall, and bubble expansion continued for ≥700 microseconds. Furthermore, cavitation bubbles were created much more frequently in the canal model than in free water.

Conclusions

These results suggest that the cleaning mechanism of an Er:YAG laser within the root canal might depend on rapid fluid motion caused by expansion and implosion of laser-induced bubbles.     

Disinfection of root canals with photon-initiated photoacoustic streaming

Introduction

This study set out to compare the efficacy of laser-activated and ultrasonically activated root canal disinfection with conventional irrigation, specifically its ability to remove bacterial film formed on root canal walls.

Methods

Seventy human premolars were shaped to an apical size #20, taper .07, sterilized, and contaminated in situ with oral bacteria for 1 week and incubated for 2 more weeks. Irrigation was done with 6% NaOCl (group 1), NaOCl ultrasonically activated with blunt inserts (group 2), or a pulsed erbium:YAG laser at nonablative settings (group 3) for a total of 60 seconds each. Positive and negative controls were also included. Aerobic bacterial sampling was performed, and the incidence of positive samples after 24 and 48 hours as well as bacterial counts (colony-forming units) were determined. Fixed and demineralized sections 1 mm and 4 mm off the apex were Brown-Brenn stained and assessed for remaining intracanal bacteria/biofilm and dentinal tubule penetration.

Results

All 3 canal disinfection protocols significantly reduced bacterial counts (P < .001). None of the 3 techniques predictably generated negative samples, but laser-activated disinfection was superior to the other 2 techniques in this aspect (P < .05). Histologic sections showed variable remaining bacterial presence in dentinal tubules at the 4-mm level and significantly less bacterial biofilm/necrotic tissue remaining at the 1-mm level after laser-activated irrigation (P < .05).

Conclusions

Under the conditions of this combined in situ/in vitro study, activated disinfection did not completely remove bacteria from the apical root canal third and infected dentinal tubules. However, the fact that laser activation generated more negative bacterial samples and left less apical bacteria/biofilm than ultrasonic activation warrants further investigation.     

铒激光备洞对牙体与充填体间纳米渗漏和粘结强度的影响

目的评价铒(Er:YAG)激光和高速涡轮手机备洞,对复合树脂充填后牙体与充填体间纳米渗漏和粘结强度的影响。方法选32颗离体前磨牙平均分成两组,对照组用高速涡轮手机备洞;实验组用Er:YAG激光备洞,随后进行光固化复合树脂充填。两组各取8颗,进行纳米渗漏测试,扫描电镜(scanning electron micrographic,SEM)观察渗漏情况。其余样本检测微拉伸强度。使用SPSS 20.0统计软件对各组微拉伸强度进行独立样本t检验。结果在牙体与充填体间,实验组几乎没有纳米渗漏产生,对照组则产生纳米渗漏带。微拉伸强度:对照组(16.10±4.91)MPa,实验组(26.53±3.61)MPa,实验组微拉伸强度大于对照组,两组间差别有统计学意义(P<0.05)。结论与涡轮手机相比,Er:YAG激光备洞的纳米渗漏程度更低,粘结强度更好。     

Effect of Er:YAG laser and EDTAC on the adhesiveness to dentine of different sealers containing calcium hydroxide

AIM: To evaluate the effect of 15% EDTAC solution and Er:YAG laser irradiation on the adhesiveness to dentine of root canal sealers containing calcium hydroxide. METHODOLOGY: The crowns of 60 maxillary human molars were ground until dentine was exposed. The teeth were divided into three groups of 20 teeth: group I, the dentine surface received no treatment; group II, 15% EDTAC solution was applied to the dentine; group III, the dentine received Er:YAG laser application (11 mm focal distance with perpendicular incidence to dentine surface; 4 Hz frequency; 200 mJ energy; 2.25 W potency; 62 J total energy; 1 min application time). Aluminium cylinders filled with the sealers, Sealer 26, Apexit, Sealapex and CRCS, were then applied to the treated surfaces. Adhesiveness was measured with a universal testing machine, with traction results given in MegaPascals (MPa). These results were submitted to anova tests. RESULTS: Statistical analysis showed significant differences (P < 0.01) amongst adhesiveness values of the sealers and treatments tested. Thus, sealers could be ranked in decreasing adhesiveness values: Sealer 26, CRCS, Apexit, Sealapex. Er:YAG laser irradiation and EDTAC solution application increased adhesiveness values only for Sealer 26 and Apexit. Laser irradiation was superior to EDTAC application only for Sealer 26 adhesiveness values. CONCLUSIONS: Er:YAG laser is as efficient as EDTAC solution in increasing adhesiveness of root canal sealers containing calcium hydroxide to human dentine.     

Er��YAG��������Gluma���������������С��Ч���о�

目的探讨Er:YAG激光与Gluma脱敏剂联合应用对牙本质小管的封闭作用。方法选取2010年3—6月于山西医科大学口腔医院口腔颌面外科因正畸拔除的24颗前磨牙,制成厚约2mm的牙本质片。根据其表面处理方式的不同随机分为4组:对照组、Er:YAG激光组、Gluma脱敏剂组、联合应用组(Er:YAG激光联合Gluma脱敏剂),每组6颗前磨牙。处理后,扫描电镜观察各组牙本质小管形态特征,并测量牙本质小管口的直径和相对面积。结果联合应用组中牙本质小管口的直径和相对面积均明显小于其他各组,且差异有统计学意义(P<0.05)。结论 Gluma和Er:YAG联合应用对牙本质小管的封闭作用优于单独应用Gluma脱敏剂或Er:YAG激光。