Effect of Different Irradiation Times on the Occlusion of Dentinal Tubules When Using a Nd:YAG Laser: An <i>in Vitro</i>SEM Study

Objective: To evaluate the effect of different irradiation times on the occlusion of dentinal tubules when using Nd:YAG laser. Background data: Dentin hypersensitivity is a frequent problem that has limited treatment success despite many chemical and physical therapies. Methods: Four coronal dentin disks 2 mm thick were cut with a low-speed diamond saw from four freshly extracted intact first molars. The coronal dentin surface of each disk was divided into four regions, each approximately 2 mm × 3 mm. The dentin surfaces were treated with 27% EDTA then the four regions irradiated separately in a randomized pattern with a Nd:YAG laser (120 mJ, 5 Hz), using irradiation times of 0 s, 20 s, 40 s and 60 s, representing laser energies of 0 J/cm2, 200 J/cm2, 400 J/cm2 and 600 J/cm2, respectively. SEM photomicro-graphs were taken at 1500× and 3000× to calculate the dentinal tubule orifice occlusion rates and to measure the tubule diameters, respectively. Results: For the laser irradiation times of 0 s, 20 s, 40 s and 60 s, the corresponding dentinal tubule occlusion rates were 2.05 (SD 0.29)%, 10.01 (1.71)%, 23.58 (2.51)% and 90.23 (2.24)%, respectively;and the tubule diameters were 4.18 (0.32) μm, 3.46 (0.24) μm, 1.69 (0.32) μm and 0.12 (0.02) μm, respectively. There were significant differences among all groups for both measured variables (p ≤ 0.005). Conclusions: Within the limitations of this in Vitro study, when using a Nd:YAG laser at 120 mJ and 5 Hz, an irradiation time of 60 s achieved the best sealing of the coronal dentinal tubule orifices.

Effect of Calcium Phosphate Glass on Dentinal Tubule Sealing after Irradiation with the Carbon Dioxide Laser

The aim of this study was to evaluate the dentinal tubule sealing and acid resistance of dentin specimens following the application of calcium phosphate glass powder prior to irradiation with a CO2(carbon dioxide)laser.Dentin models simulating open dentinal tubules were divided into two groups:experimental(calcium phosphate glass slurry applied to the dentin surface)and control(no slurry applied to the surface).All specimens in the experimental group and five specimens in the control group were irradiated with a CO2 laser.The defocused laser beams(0.5 and 1 W)were applied(spot size,5 mm in diameter)from a distance of 20 mm for 10 s.The surfaces and cross-sectional areas of the specimens were examined using an SEM(scanning electron microscope).In addition,the resistance to acid was evaluated in these specimens.The open dentinal tubules in the control groups were sealed following irradiation with the CO2 laser at 0.5 W and 1.0 W.Likewise,sealing of open dentinal tubules was observed in the experimental group after CO2 laser irradiation.The acid resistance of the dentin surface was improved after CO2 laser irradiation;specimens in the experimental group presented with significantly lower amounts of Ca ion release compared to those in the control group.These findings indicate that CO2 laser irradiation alone or after the application of calcium phosphate glass powder can effectively seal the dentinal tubules and alleviate dentin hypersensitivity.

The Prevalence of Dentine Hypersensitivity and Gingival Recession among Jordanian Patients at JUST Dental Teaching Center

Aims: to determine the prevalence of gingival recession and dentine hypersensitivity among the study population, and evaluate the distribution of dentine hypersensitivity among various types of teeth in mild, moderate and severe degrees of gingival recession. Relationship between the severity of gingival recession and dentine hypersensitivity was also evaluated. Materials and Methods: Clinical examination was conducted on six hundred and seventy-six patients (283 males and 393 females). Their ages ranged from 18 to 74 years old (mean 35.4, SD = 11.2). A valid and reliable questionnaire was filled by the participated patients. Results: The prevalence of gingival recession was 79.0%, and the prevalence of dentine hypersensitivity within the patients with gingival recession was 23.6%. The most common teeth affected by dentine hypersensitivity were the lower incisors. Dentine hypersensitivity was more commonly found in teeth with mild recession. Conclusion: Increased gingival recession does not necessarily mean increased incidence of dentine hypersensitivity.

The mechanism of dentine hypersensitivity:Stimuli-induced directional cation transport through dentinal tubules

Dentine hypersensitivity is an annoying worldwide disease,yet its mechanism remains unclear.The long-used hydrodynamic theory,a stimuli-induced fluid-flow process,describes the pain processes.However,no experimental evidence supports the statements.Here,we demonstrate that stimuli-induced directional cation transport,rather than fluid-flow,through dentinal tubules actually leads to dentine hypersensitivity.The in vitro/in vivo electro-chemical and electro-neurophysiological approaches reveal the cation current through the nanoconfined negatively charged dentinal tubules coming from external stimuli(pressure,pH,and temperature)on dentin surface and further triggering the nerve impulses causing the dentine hypersensitivity.Furthermore,the cationic-hydrogels blocked dentinal tubules could significantly reduce the stimuli-triggered nerve action potentials and the anionhydrogels counterpart enhances those,supporting the cation-flow transducing dentine hypersensitivity.Therefore,the inspired ion-blocking desensitizing therapies have achieved remarkable pain relief in clinical applications.The proposed mechanism would enrich the basic knowledge of dentistry and further foster breakthrough initiatives in hypersensitivity mitigation and cure.

Effect of low level laser therapy on dental pulp during orthodontic movement

AIM: To validate the protocol described here to be used in future clinical trials related to the effect of laser therapy on dental pulp. METHODS: Histologically treated samples from eight human healthy premolar teeth obtained from the middle root level were distributed in four groups: group 1(G1) absolute control; group 2(G2) only laser irradiation; group 3(G3) exposed only to orthodontics; and group 4(G4) treated with orthodontics and laser. Laser treatment was performed at 830 nm wavelength, 100 mW(energy 80 J/cm2, 2.2 J), for 22 s in the vestibular surface and 22 s in the palatal surface, 1 mm away from the dental root mucosa. Three staining methods were performed: hematoxylin-eosin(HE), Masson's Trichrome method and Gomori's method.RESULTS: The pulp histology parameters were evaluated and the results classified in to 3 parts: an inflammatory response, soft tissue response(dental pulp) and hard tissue response(dentin and predentin). There was no inflammation(chronic or acute) in any of the evaluated groups. The zones of pulp necrosis were found in one premolar of G3 and in one of G4; in groups G2 and G4 there was higher angiogenesis than in the other two groups. G4 group presented the highest level of vascularization. A reduced nerve density was observed in G3. A G2 specimen showed increased nerve density. A higher rate of calcification was observed in G1 compared to G2. Denticles, either real or false, were observed in G1, G2 and G3. Sclerosis of dentin and focal dentin loss was observed among all the groups. Secondary dentin was present in one sample in G1 and G2. A necrosis zone was found in one sample of G3 and G4. No differences between groups were observed in the odontoblast irregularity layer but the layer was wider in the group treated with laser only. A notable difference was detected in reduction of the cell-free layer between the groups G1 and G4. The findings in pulp tissue favor its adaptative response against dental movement induced by orthodontics. No definitive conclusions may be derived as this is a pilot study. CONCLUSION: The protocol described here was shown to be an effective method to evaluate changes in dental pulp submitted to low level laser in teeth under orthodontic movement.

Which treatment protocol, among classical methods and/or various laser applications is the most effective in root canal disinfection, <i>in vitro</i>? A systematic review

Purpose: The aim of this systematic review was to answer the question “Which treatment protocol, am- ong classical methods and/or various laser applica- tions is the most effective in root canal disinfection, in vitro”. Materials and Methods: A MEDLINE, a Co- chrane and an Embase search (three specified search- es) were conducted to identify randomized controlled trials (RCT) until June 2010, conducted on human teeth and published in English, German or French language, examining the root canal disinfection after the use of lasers with or without mechanical instru-mentation. Additionally, hand search was conducted and contact with authors, when needed. Results: The MEDLINE, the Cochrane and the EMBASE search identified 240, 28, and 35 published articles, respec-tively. Ten articles from the MEDLINE and 5 articles from the Cochrane search (that were also identified in the MEDLINE search) met the inclusion and va-lidity assessment criteria. In E. faecalis elimination, instrumentation of the root canal and diode laser/665 nanometer/1 Watt (diode laser/665 nm/1 W) irradia-tion with the combined effect of Methylene Blue (MB) as photosensitizing agent (logCFU/ml = 1636) seemed to be the best method. In P. aeruginosa and in A.naeslundii elimination, instrumentation of the root canal followed by irrigation with 5, 25% NaOCl (log-CFU/ml = 0) seemed to be the best method. In gen-eral, instrumentation of the root canal followed by irrigation with 5, 25% NaOCl (logCFU/ml = 0) and instrumentation of the root canal and Er: YAG laser/ 2940 nm/0.8 W irradiation (logCFU/ml = 1924) seemed to be the best (polymicrobial studies). Conclusions: There are treatment protocols with the assistance or not of laser irradiation that can eliminate E. faecalis, E. coli and S. aureus inside the root canal. However, there is a serious number of S. anginosus, F. nuclea-tum, A. naeslundii and P. aeruginosa that remain in-side the root canal even after laser irradiation. New research is needed in order to set a treatment proto-col effective in the root canal disinfection from all bac-teria that are related to endodontic origin pathology.

A Study on Morphologic Feature of Dentinal Hypersensitivity by SEM

The morpohologic feature of radicular dentin in sensitive and naturally desensitive area was observed with scanning electron microscopy (SEM). Eight specimens were taken from six patients with periodontal diseases. It was established that the orifices of dentinal tubules in hypersensitive areas were much more than those in naturally desensitive areas. The dimension of the orifices in hyperoensitive areas was much larger than that in naturally desensitive areas. The results suggest that theie is relationship between dentin moophology and dentin hypersensitivity. In this article, a new dentin bipopsy technique with hollow drill was reported also.

Nd:YAG激光和Er:YAG激光治疗牙本质敏感的临床对比研究

目的探讨Nd:YAG激光和Er:YAG激光治疗牙本质敏感(Dentin Hypersensitivity,DH)的效果。方法收治佛山市第一人民医院2021年3月至2022年12月期间就诊的牙本质敏感93例患者共259颗牙,患者均在受到冷、酸、甜及刷牙等刺激后存在酸痛感,诊断为DH。随机分为3组,分别给予常规脱敏剂治疗组(31例患者,86颗患牙)、Nd:YAG激光治疗组(31例患者,90颗患牙)、Er:YAG激光治疗组(31例患者,83颗患牙)3种方法,其中激光组尝试改变激光照射参数及时间,寻求最好的治疗参数。对比3种脱敏方法的即刻效果、1周效果、1个月效果及3个月效果。结果治疗前3组对冷空气及机械刺激反应的VAS评分无明显差异(P>0.05);治疗后各个时间段Nd:YAG激光组和Er:YAG激光组对冷空气刺激反应均明显轻于对照组(P<0.05)。治疗后各个时间段Nd:YAG激光组和Er:YAG激光组对机械刺激反应均明显轻于对照组(P<0.05)。3组经治疗后均获得一定疗效,Nd:YAG激光组和Er:YAG激光组的效果好于常规组,但差异无统计学意义(P>0.05)。结论Nd:YAG激光、Er:YAG激光治疗DH与常规脱敏方法相比,明显降低患者的冷空气和机械刺激反应,在一定程度上提升了治疗效果。

生物活性材料治疗修复中常见的牙本质敏感症的效果研究

目的:牙本质敏感症(dentin hypersensitivity,DH)作为口腔中常见的一种症状和疾病,可能对患者的生活质量产生较大影响,本研究通过体外实验比较Regesi生物活性材料、Gluma脱敏剂和可乐丽菲露Clearfil SE Bond两步法粘接剂对牙本质小管封闭程度及耐久性的差异,为其用于牙本质敏感症的治疗提供数据支持。方法:体外实验中,用离体牙制作牙本质敏感模型,根据脱敏材料的不同进行随机分组(对照组:人工唾液组;A组:Regesi组;B组:Gluma组;C组:Clearfil SEBond组),通过SEM观察脱敏剂作用后,4组牙本质敏感模型的形貌及牙本质小管封闭效果,分析对比其脱敏效果的差异,并通过耐磨性实验,分析材料间脱敏效果持久性之间的差异及表面硬度的差异。结果:SEM观察可见A、B、C组的牙本质小管封闭效果均优于对照组,结果有统计学差异,其中A组封闭效果最好,较其他两组有统计学差异。耐磨性实验前后,A组的表面硬度均高于其他三组,结果有统计学差异。结论:Regesi生物活性材料较Gluma脱敏剂和Clearfil SE Bond两步法粘接剂对牙本质小管的封闭程度及耐久性能更佳,能更好地治疗牙本质敏感症。

Mineral formation on dentin induced by nano-bioactive glass

The object of this study was to evaluate the effect of bioactive glass （BG） size on mineral formation on dentin surfaces. Totally demineralized dentin discs were treated using BG suspensions with different particle sizes： i.e., microscale bioactive glass （m-BG）, submicroscale bioactive glass （sm-BG） and nanoscale bioactive glass （n-BG）. Field-emission scanning electron microscopy and 3D profile measurement laser microscopy were used to observe the surface morphology and roughness. It was found that all BG particles could promoted mineral formation on dentin surfaces, while plug-like depositions were observed on the dentin discs treated by n-BG and they were more acid-resistant. The present results may imply that n-BG has potential clinical application for dentin hypersensitivity treatment.

Er:YAG激光和传统车针去龋后牙本质粘接强度的比较

目的:比较使用不同模式Er:YAG激光以及传统车针去龋后牙本质与复合树脂的粘接强度。方法:选用人类离体磨牙模拟龋坏,分别采用Er:YAG激光中短脉冲(medium short pulse,MSP)模式、Er:YAG激光超短脉冲(super short pulse,SSP)模式和传统车针去除模拟的龋坏后,采用自酸蚀粘接剂将牙体标本与复合树脂粘接制成试件。使用万能试验机对试件进行拉伸试验,测得断裂负荷和粘接强度,并采用单因素方差分析和Tukey多重比较进行统计学分析。采用扫描电子显微镜观察3种不同去龋方式处理后的牙本质表面形态,以及涂布自酸蚀粘接剂并固化后试件的横截面形态。结果:使用Er:YAG激光MSP模式处理后牙本质与复合树脂的粘接强度最高,SSP模式处理后次之,传统车针处理后最低,但差异无统计学意义(P>0.05)。扫描电子显微镜图像显示,Er:YAG激光MSP模式处理后的牙本质表面较平坦,牙本质小管内几乎没有残屑;Er:YAG激光SSP模式处理后的牙本质表面呈现鳞片状,牙本质小管内可见少量碎屑;而传统车针处理后牙本质小管大部分处于被表面牙本质部分甚至完全遮盖的状态,牙本质小管内充满残屑。结论:使用Er:YAG激光去龋相比传统车针去龋可以获得较好的牙本质粘接强度,且对牙本质小管的处理深度和洁净度明显优于传统车针去龋,其中MSP模式更佳。

铒激光治疗牙本质敏感的综合护理干预

目的:探讨铒激光治疗牙本质敏感的综合护理干预措施。方法:选取2023年01月至2023年06月在我科因牙本质敏感就诊的42例患者为研究对象,共计108个患牙接受铒激光脱敏治疗,在术前、术中、术后制定并实施综合护理干预措施,评价术后即刻和术后6个月的疗效以及患者的护理满意度。结果:42例患者治疗过程顺利,无护理相关不适发生,铒激光即刻治疗有效率达98.1%,6个月后随访治疗有效率达93.5%,对综合护理满意率为97.6%,患者在铒激光治疗后即刻以及治疗后6个月时的MDAS评分也明显低于治疗前(P<0.05)。结论:对铒激光治疗牙本质敏感患者实施综合护理干预,有利于治疗顺利完成、提高疗效、缓解焦虑,增加患者满意度。

通过仿生矿化修复人体牙齿结构

牙齿结构损伤、缺失导致的龋齿和牙齿过敏等问题严重影响了人们的日常生活。众多学者针对这些问题提出了各式各样的解决方案,但是最终结果与原生牙齿结构相比还是不尽人意。生物矿化是研究生物体内的硬组织(如牙齿、骨骼和贝壳等)的形成过程。一般地,这类硬组织是由有机生物分子调控无机矿物形成的多级、有序且能供生命体实现特定功能的有机-无机复合材料。近年来许多研究人员通过模拟牙齿自然矿化的过程,仿生设计和合成出人工纳米材料来修复牙釉质、牙本质等牙齿结构的方法取得了重要成效。与传统的使用激光、有机粘合剂等修复手段相比,仿生矿化方法所修复的牙齿部位在组成、结构和力学性能上与原生牙齿相近,具有无损、生物兼容、抗菌防污等优点。因此仿生矿化方法有望从根本上解决牙齿结构修复的难题。现对牙齿结构、牙齿脱敏治疗方法、牙齿结构仿生再矿化和牙齿修复材料的研究现状及进展进行综述。

含锶脱敏牙膏对牙本质过敏症脱敏作用的Meta分析

目的:采用Meta分析评价含锶脱敏牙膏对牙本质过敏症(DH)的治疗效果,为临床治疗提供参考。方法:收集1990年1月1日至2020年3月1日PubMed,EMBASE,Web of Science,CENTRAL和CNKI等数据库关于研究含锶脱敏牙膏对DH的随机对照试验(RCT)文献,运用Stata 14.0软件对提取的所有文献数据进行Meta分析。结果:共纳入8篇RCT文献,根据8项研究的最长试验周期,对含锶脱敏牙膏和对照组牙膏干预后进行探诊及空气喷吹检测差异进行Meta分析,试验组与对照组在探诊、空气检测敏感值之间比较,差异均无统计学意义(P>0.05);根据试验时间长短、结局指标分类,分别合并即刻、≤1、2、4、6、8、12周的探诊敏感、空气检测敏感值进行亚组分析,结果显示试验组与对照组在探诊、空气检测敏感值之间比较,差异均无统计学意义(P>0.05)。结论:含锶脱敏牙膏和对照组牙膏相比,不能更有效地减轻DH,需要更多的研究来进一步验证其对缓解DH的效果。

脱敏剂对活髓牙全瓷修复影响的相关实验研究

目的研究不同类型脱敏剂对活髓牙牙本质小管封闭以及全瓷修复黏接效果的影响,为临床上活髓牙全瓷修复选用脱敏剂提供依据。方法收集健康完好离体第三磨牙12颗,牙体预备后制备牙本质片,将牙冠分为两半,共分出牙体24块,随机分为4组,每组6块:对照组(仅清洁牙本质表面并吹干)、双氟-12组(涂布氟化物脱敏剂:双氟-12脱敏剂)、奥敏清组(涂布生物活性玻璃为主要成分的脱敏剂:奥敏清脱敏剂)、Gluma组(涂布HEMA-戊二醛类脱敏剂:Gluma脱敏剂)。SEM电镜扫描不同实验组表面特征,计算牙本质小管封闭率。在各组实验件表面按规范程序黏接瓷块后,万能力学测试仪检测最大剪切力,分析实验结果。结果电镜扫描结果显示,Gluma组界面光滑平整,沉积物少,视野内仅有少数牙本质小管口可见。奥敏清组的牙本质小管封闭率(33.6%)显著高于对照组(10.7%),显著小于Gluma组(82.1%)和双氟-12组(80.0%),差异有统计学意义(P<0.05)。与对照组比较,Gluma组显著增强了最大剪切力(P<0.05),奥敏清组和双氟-12组最大剪切力显著下降(P<0.05)。结论含有HEMA-戊二醛类脱敏剂是一种合适的全瓷冠修复活髓隐裂牙的脱敏剂,而氟化物和生物活性玻璃类脱敏剂均不建议用于全瓷冠修复活髓隐裂牙的脱敏。

Preliminary Study on Human Radicular Dentinal Characterization in both Sensitive and Naturally Desensitive Areas with SEM

The morphologic feature of radicular dentin in sensitive and naturally desensitive areas was observed with scanning electron microscopy(SEM). Eight specimens were taken from six-patients with periodontal diseases. It was established that the orifices of dentinal tubules in hypersensitive areas were much more than those in naturally desensitive areas. The dimension of the orifices in hypersensitive areas was much larger than that in naturally desensitive areas. The results suggest that there is relationship between dentin morphology and dentin hypersensitivity. In this article, a new technique of dentin biopsy with hollow drill was reported also.

铒激光预处理对牙本质、牙釉质粘结强度及CAD/CAM玻璃陶瓷嵌体修复牙体缺损边缘微渗漏的影响

目的:探讨铒激光预处理对牙本质、牙釉质粘结强度及CAD/CAM玻璃陶瓷嵌体修复牙体缺损边缘微渗漏的影响。方法:收集2020年1月—2023年1月口腔外科门诊拔除的新鲜、无龋坏变色、无隐裂智齿62颗,根据预处理方式不同,随机分为铒激光组和磷酸组,每组31颗,每组再随机分为2份,分别用于粘结强度测试(16颗)和微渗漏测试(15颗)。比较2组牙釉质、牙本质抗剪切粘结强度和微渗漏程度及微渗漏评分分布情况。采用SPSS 17.0软件包对数据进行统计学分析。结果:铒激光组牙釉质、牙本质抗剪切粘结强度显著高于磷酸组(P<0.05);铒激光组侧壁、龈壁微渗漏程度显著低于磷酸组(P<0.05),铒激光组侧壁微渗漏评分主要为1分和2分,磷酸组侧壁微渗漏评分主要为2分,2组侧壁微渗漏评分分布相比,差异有统计学意义(P<0.05);铒激光组龈壁微渗漏评分主要为1分和2分,磷酸组龈壁微渗漏评分主要为2分和3分,2组龈壁微渗漏评分分布相比,差异有统计学意义(P<0.05)。结论:铒激光预处理可提高瓷嵌体与牙本质、牙釉质粘结强度,同时还可减少CAD/CAM玻璃陶瓷嵌体微渗漏,增强嵌体边缘密合性。

自体牙本质颗粒联合Nd:YAG激光在前牙区牙周炎患者拔牙术后中的应用效果

【目的】探讨自体牙本质颗粒联合Nd:YAG激光在前牙区牙周炎患者拔牙术后中的应用效果。【方法】选取2021年5月至2023年3月本院收治的123例前牙区牙周炎拔牙术后患者,按治疗方法不同分为观察组(n=63,63颗牙)和对照组(n=60,60颗牙),对照组采用Nd:YAG激光治疗,观察组在对照组基础上加用自体牙本质颗粒治疗,比较两组治疗效果。【结果】治疗后1年,观察组种植成功率显著高于对照组(P<0.05),但两组美学效果比较,差异无统计学意义(P>0.05);治疗后7 d,两组疼痛程度均下降,且观察组低于对照组(P>0.05)。治疗后1年,两组菌斑指数(PLI)、出血指数(SBI)、牙龈指数(GI)、牙周袋深度(PD)均下降(P<0.05),且观察组PLI、SBI、GI、PD低于对照组。观察组并发症总发生率显著低于对照组(χ^(2)=0.230,P=0.631)。【结论】自体牙本质颗粒联合Nd:YAG激光应用于前牙区牙周炎拔牙术后患者中,可显著提高患者咀嚼效率、美学效果,改善牙周功能,且并发症发生率较低,值得临床推广应用。

ND∶YAP、ND∶YAG激光联合氟化氨银、牙本质黏结剂、Gluma脱敏剂治疗牙本质敏感的临床研究

目的探讨ND∶YAP、ND∶YAG激光联合38%氟化氨银、牙本质黏结剂、Gluma脱敏剂治疗牙本质敏感的临床效果。方法将120例牙本质敏感患者的330颗牙本质过敏(dentin hypersensitivity,DH)患牙随机分为11个治疗组,其中5组分别进行38%氟化氨银、牙本质黏结剂、Gluma脱敏剂、ND∶YAP激光、ND∶YAG激光脱敏治疗,另外6组进行激光联合治疗,评价各治疗组治疗前及治疗后即刻、治疗后4和8周对温度刺激敏感度的变化,采用视觉模拟量表(visual analogue scale,VAS)对温度敏感度进行检测。结果单独治疗各组术后即刻温度刺激均有改善(P<0.05),治疗效果随时间推移减弱;治疗第8周,氟化氨银组、牙本质黏结剂组、Gluma脱敏剂组完全失效(P<0.05),ND∶YAP激光组、ND∶YAG激光组疗效减弱(P<0.05)。在激光联合治疗中:各组在治疗后3个时间点均有效果(P<0.05);在治疗后第8周,ND∶YAP激光组、ND∶YAG激光组与联合治疗组均维持治疗效果(P<0.05),激光单独治疗组效果弱于联合治疗组(P<0.05)。结论激光联合脱敏剂治疗牙本质敏感具有稳定持久的治疗效果。

970 nm半导体激光联合多乐氟封闭牙本质小管效果的体外研究

目的:研究半导体激光和多乐氟联合使用对牙本质小管的封闭效果。方法:28个牙本质小管开放模型分别来源于28颗离体前磨牙,随机分为4组(n=7),分别用多乐氟(A组)、半导体激光(B组)、多乐氟→半导体激光(C组)、半导体激光→多乐氟(D组)于以牙本质小管封闭处理。扫描电镜观察牙本质小管封闭情况,Imag,E-pro plus 6.0分析封闭率、封闭深度,X射线能谱分析封闭物中氟含量水平。结果:A、B、C、D组牙本质小管封闭率(%)分别为66.25±12.26、67.65±18.40、85.45±10.87和84.05±10.95(C组、D组分别与A组和B组比较,P<0.05);牙本质小管封闭深度(μm)分别为5.32±0.94,5.58±0.84,8.25±1.06和8.12±1.07(C组、D组分别与A组和B组比较,P<0.05);A、C、D组牙本质小管封闭物中氟含量(%)分别为2.04±0.37,3.01±0.72和2.44±0.86(A组与C组比较,P<0.05)。结论:970 nm半导体激光和多乐氟对牙本质小管均有封闭作用,联合应用封闭效果优于单独应用,不同使用顺序对封闭效果无影响。