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1.
Er,Cr:YSGG激光照射对牙根尖封闭效果影响的实验研究   总被引:3,自引:0,他引:3  
目的:深入探讨在根尖倒充填术中Er,Cr:YSGG激光照射对牙根尖的封闭效果,为此激光在口腔临床上的应用与推广提供重要的理论与实验依据。方法:将56颗新拔除的单根牙随机分成7组,每组8颗牙。去除牙冠,常规进行根管预备、根管充填。将倒充填的牙根尖进行预备,然后银汞合金倒充填。预备方法:1手机切除根尖后,制备成烧瓶状洞形;2手机处理方法同1,然后Er,Cr:YSGG激光于不同能量(1W、2W)及不同方式(喷水或无水)下对洞内壁进行照射。结合微渗漏检测与扫描电镜观察对Er,Cr:YSGG激光照射后的牙根尖封闭效果进行评估。结果:Er,Cr:YSGG激光可有效去除根切面上的玷污层及碎屑;与手机加银汞倒充填组相比,激光照射后的根尖染料微渗漏深度有所减少;但只有1WEr,Cr:YSGG激光于无水条件下照射时,根尖染料微渗漏深度显著减少(P<0.05)。结论:Er,Cr:YSGG激光应用于根尖倒充填术中可减少微渗漏的发生;促进根尖封闭;在特定的能量参数下可获得优于常规银汞倒充填术的治疗效果。因此我们推荐临床上将Er,Cr:YSGG激光照射与常规银汞倒充填术结合使用,这将有助于提高根尖倒充填术治疗的成功率。  相似文献   

2.
Er,Cr:YSGG激光是新一代水动力生物激光系统,其特性和优势正在口腔医疗的应用中越来越受到关注,该文对Er,Cr:YSGG激光对于牙体组织的去龋能力、清除玷污层和蚀刻作用以及对于牙周病变牙根表面的杀菌、去除菌斑和牙石的能力等方面的研究进展进行综述。  相似文献   

3.
目的:观察不同能量输出的Er,C r:YSGG激光照射对牙周病牙根面的影响,探讨Er,C r:YSGG激光用于牙周治疗的可行性和有效性。方法:选择因牙周病松动Ⅲo而拔除牙12颗,随机分3组,每组4颗。分别以1.5 W、2.0 W、2.5 W激光照射。扫描电镜(SEM)观察各组牙根表面和纵剖面。结果:低倍镜下各组根面改变无明显差异,表面干净,粗糙程度均匀,未见明显弹坑状痕迹;高倍镜下1.5 W激光照射组显示根面粗糙程度更均匀一致,无弹坑状改变,无熔融、炭化迹象,未见牙本质小管暴露。结论:Er,C r:YSGG激光能有效去除牙周病牙根面玷污层及病变牙骨质,根面无熔融、炭化等改变。1.5 W激光照射组优于2.0 W组和2.5 W组。  相似文献   

4.
探讨常规根管预备后使用不同能量参数Er,C r:YSGG激光进行根管内照射对根管封闭效果的影响,为此激光在根管治疗领域的临床应用提供重要的实验依据。选择新拔除的单根管牙80颗,分成4组,每组20颗牙。常规根管预备后,分别使用1 W、2 W、3 W Er,C r:YSGG激光于有水条件下进行根管内照射,另选一组不做任何处理,作为阴性对照。扫描电子显微镜下观察根管内壁形态学改变后,常规根管充填,检测根管微渗漏情况。采用单因素方差分析及q检验进行统计学处理。结果可见:(1)形态学观察:与对照组相比,激光照射均可有效去除根管内壁的玷污层及碎屑;牙本质小管口清晰可见;未见熔融及炭化等热损伤改变;其中3 W激光处理后根管内壁形态最为理想。(2)微渗漏检测:与对照组相比,各激光组根管微渗漏深度均显著减少(P<0.05);但各激光组间比较无显著性差异(P>0.05)。综上,使用Er,C r:YSGG激光进行根管内照射可达到较为理想的根管清洁目的,显著改善根管充填后的封闭效果,因此有望在临床上应用提高根管治疗的成功率。  相似文献   

5.
本文用 1千牛电液疲劳实验机检测充填材料与牙面之间的粘结力 ,发现 :在牙釉质组中 ,酸蚀组、6瓦激光切割组及 6瓦激光切割联合酸蚀组抗剪切粘结强度无显著性差异 (P >0 .0 5) ;在牙本质组中 ,酸蚀组、4瓦激光切割组及 4瓦激光切割联合酸蚀组抗剪切粘结强度也无显著性差异 (P >0 .0 5)。并通过SEM观察激光处理后牙体表面结构的变化 ,发现激光切割后牙釉质表面不平呈层状 ,无玷污层 ,釉柱未见破坏 ;牙本质小管开放 ,表面无玷污层 ,达到酸蚀的效果。因此Er,Cr :YSGG激光切割牙体硬组织具有传统钻切割与酸蚀刻的联合作用 ,可以代替传统的酸蚀方法。  相似文献   

6.
为探讨利用光学相干成像技术(OCT)定量评估Er:YAG激光消融后牙本质表面特征的可行性,以人无龋第三磨牙为试验样品,制备牙本质圆盘,用50μs超短脉宽Er:YAG激光在水喷雾下垂直切削牙本质表面,对照组为金刚砂球钻切削和砂纸抛光组,OCT观察表层性状及测量表层光强改变,组织病理切片分析表层结构;表面切削后使用37%磷酸蚀刻30 s,扫描电镜(SEM)观察表面形貌,能量色散X射线光谱仪(EDX)测量表面元素组成。OCT显示,所有试验组牙本质表层光散射特性均发生改变,可见高亮层形成,激光组高亮层厚度高于砂纸组和球钻组(P0.05)。组织切片显示,激光组表层可见连续的嗜碱性深染改性层,球钻组及砂纸组改性层少且不连续,改性层厚度与OCT高亮层结果相关。SEM显示,酸蚀后激光组牙本质小管开口扩大,但未见胶原纤维网暴露。酸处理后激光组的钙、磷含量均高于砂纸及球钻组(P0.05),这意味着受激光影响的牙本质变得更耐酸。研究结果表明,OCT可能成为一种可精确评估牙本质表层特性的无创性工具,这将有助于牙医确定粘接修复策略。  相似文献   

7.
自粘结树脂水门汀粘结牙本质的超微结构观察   总被引:1,自引:0,他引:1  
目的:通过扫描电镜比较4种树脂水门汀(RelyX Unicem、PanaviaF、VariolinkⅡ、Vitique)粘结牙本质时超微结构的差异。方法:新鲜拔除的人无龋坏第三磨牙12颗,随机分为4组(n=3),制备牙本质粘结面,分别与4种树脂水门汀(RelyX Unicem、PanaviaF、VariolinkⅡ、Vitique)粘结处理,将所得粘结试件二次纵切,SEM观察牙本质粘结界面。结果:四种树脂水门汀与牙本质粘结中,RelyXUnicem未见明显树脂突,而PanaviaF、VariolinkⅡ和Vitique均可见明显树脂突形成。结论:新型自粘结树脂水门汀粘结牙本质的超微结构完全有别于传统树脂水门汀。  相似文献   

8.
研究不同表面处理条件下Er:YAG激光照射对牙釉质及牙本质修复效果的影响。80个样本随机分成牙釉质和牙本质2大组,再根据处理方式随机分为4小组:①酸蚀(37%磷酸);②Er:YAG激光;③自酸蚀粘接处理剂;④Er:YAG激光+自酸蚀粘接处理剂。与树脂加强型玻璃离子水门汀(RMGIC)粘接后37℃水浴中储存24 h,用万能测试机测定粘接剪切强度。牙釉质及牙本质组结果均为3、4小组粘结强度接近(P0.05),显著高于其他组(P0.05),1、2小组间粘结强度差别无统计学差异(P0.05)。Er:YAG激光照射可替代37%磷酸酸蚀处理方法;G-Bond自酸蚀粘接处理剂可提高牙面与RMGIC间的粘结力,Er:YAG激光处理不影响该效果。  相似文献   

9.
目的:观察新型激光光敏根管消毒剂、甲苯胺蓝和亚甲基蓝在牙本质中的渗透效果,评价三种光敏剂在牙本质中的渗透性。方法:收集新鲜拔除的离体单根管牙90颗,根管预备后随机分为三组。每组30颗。A组为新型激光光敏根管消毒剂组;B组为甲苯胺蓝组;c组为亚甲基蓝组。A、B、C三组实验根管内分别用浸有饱和的新型激光光敏根管消毒剂、甲苯胺蓝和亚甲基蓝的棉捻在根管内停留60秒。沿牙体长轴颊舌纵向劈开,倒置荧光显微镜下观察并拍照,用Photoshop8.01软件测量三种光敏剂渗透入牙本质的平均深度。结果:新型激光光敏根管消毒剂在牙本质内的渗透平均深度为553.25μm,甲苯胺蓝在牙本质内的渗透平均深度为350.75μm,亚甲基蓝在牙本质内的渗透平均深度为168.25μm。结论:新型激光光敏根管消毒剂在牙本质渗透性明显优于甲苯胺蓝和亚甲基蓝,具有良好的牙本质渗透性。  相似文献   

10.
目的:目前国内外对氟斑牙的研究主要集中在流行病学调查和临床疗效分析,对其漂白后釉质表面脱矿程度的研究却鲜有报道.观察不同程度人氟斑牙电镜下微观结构的特点,了解冷光美白对不同程度人氟斑牙釉质表面的影响,探讨冷光美白对重度氟斑牙的安全性.方法:选择因牙周病拔除的完整无龋坏的正常牙10颗,人各型氟斑牙50颗,选取颊侧典型区域制备标本.氟斑牙标本按Dean氏分类法分为轻、中、重度3组,正常牙标本作为对照组.各组标本随机分为4个亚组,A组:不做任何处理;B组:釉质表面蚀刻;C组:釉质剖面蚀刻;D组:釉质表面冷光美白,扫描电镜下观察标本的表面形貌.结果:轻度氟斑牙釉柱间隙增宽,少量晶体排列紊乱,晶间隙增宽.重度氟斑牙釉质表面凹凸不平,呈弹坑状或蜂窝状,釉柱轮廓不清,晶体排列紊乱甚至消失.中度氟斑牙居于二者之间.冷光美白后,正常牙和氟斑牙釉质表面低倍镜下均未见明显改变,高倍镜下散在浅碟状凹坑;中重度氟斑牙还伴有大量粟粒状小孔.结论:随着氟斑牙严重程度的加重,釉质表层损害程度加重.冷光美白造成釉质表层的轻微脱矿,氟斑牙稍重于正常牙.从结构和漂白后釉质表面脱矿程度方面进一步探讨氟斑牙的表面结构特点,从而为氟斑牙的临床治疗提供基础数据.  相似文献   

11.

Background

The objective of this study was to investigate the influence of Er,Cr:YSGG laser irradiated at different powers on the micromorphology and the bonding property of non-carious sclerotic dentin to resin composites.

Methods

Two hundred bovine incisors characterized by non-carious sclerotic dentin were selected, and the seventy-two teeth of which for surface morphological analysis were divided into nine groups according to various treatments (A: the control group, B: only treated with the adhesive Adper Easy One, C: diamond bur polishing followed by Adper Easy One, D-I: Er,Cr:YSGG laser irradiating at 1W, 2W, 3W, 4W, 5W, 6W output power, respectively, followed by Adper Easy One). The surface roughness values were measured by the non-contact three-dimensional morphology scanner, then the surface micromorphologies of surfaces in all groups were assessed by scanning electron microscopy (SEM); meanwhile, Image Pro-Plus 6.0 software was used to measure the relative percentage of open tubules on SEM images. The rest, one hundred twenty-eight teeth for bond strength test, were divided into eight groups according to the different treatments (A: only treated with the adhesive Adper Easy One, B: diamond bur polishing followed by the above adhesive, C-H: Er,Cr:YSGG laser irradiating at 1 W, 2 W, 3 W, 4 W, 5 W, 6 W output power, respectively, followed by the above adhesive), and each group was subsequently divided into two subgroups according to whether aging is performed (immediately tested and after thermocycling). Micro-shear bond strength test was used to evaluate the bond strength.

Results

The 4W laser group showed the highest roughness value (30.84±1.93μm), which was statistically higher than the control group and the diamond bur groups (p<0.05). The mean percentages ((27.8±1.8)%, (28.0±2.2)%, (30.0±1.9)%) of open tubules area in the 4W, 5W, 6W group were higher than other groups (p<0.05). The 4W laser group showed the highest micro-shear bond strength not only in immediately tested (17.60±2.55 PMa) but after thermocycling (14.35±2.08MPa).

Conclusion

The Er,Cr:YSGG laser at 4W power can effectively improve the bonding property between non-carious sclerotic dentin and resin composites by increasing the roughness and mean percentage area of open tubules.  相似文献   

12.
This study aimed to investigate the interaction of current one-bottle self-etching adhesives and Er:YAG laser with dentin using a tensile bond strength (TBS) test and scanning electron microscopy (SEM) in vitro. Two hundred and thirteen dentin discs were randomly distributed to the Control Group using bur cutting and to the Laser Group using an Er:YAG laser (200 mJ, VSP, 20 Hz). The following adhesives were investigated: one two-step total-etch adhesive [Prime & Bond NT (Dentsply)] and four one-step self-etch adhesives [G-Bond plus (GC), XENO V (Dentsply), iBond Self Etch (Heraeus) and Adper Easy One (3 M ESPE)]. Samples were restored with composite resin, and after 24-hour storage in distilled water, subjected to the TBS test. For morphological analysis, 12 dentin specimens were prepared for SEM. No significant differences were found between the control group and laser group (p = 0.899); dentin subjected to Prime & Bond NT, XENOV and Adper Easy One produced higher TBS. In conclusion, this study indicates that Er:YAG laser-prepared dentin can perform as well as bur on TBS, and some of the one-step one-bottle adhesives are comparable to the total-etch adhesives in TBS on dentin.  相似文献   

13.
The aluminum (Al) concentrations in the enamel and dentin of 314 human deciduous teeth were determined in order to examine the relationship between Al and dental caries. The sample teeth were divided into three groups: the sound tooth group, carious tooth group and filled tooth group. The teeth of the carious tooth group were further classified into three groups depending on the stage of caries. The Al content was determined using graphite furnace atomic absorption spectrometry. In both the enamel and dentin, the Al concentrations were unaffected by sex, but did depend on tooth type. In enamel, the Al concentration was significantly higher in the sound tooth group (42.8 +/- 37.3 microg/g) than in the three carious groups (20.7 +/- 17.1-24.9 +/- 22.0 microg/g) and the filled tooth group (27.3 +/- 25.5 microg/g). As for dentin, the Al concentration was also significantly higher in the sound tooth group (36.2 +/- 35.1 microg/g) than in the three carious groups (15.1 +/- 13.3-24.5 +/- 23.4 microg/g) and the filled tooth group (17.2 +/- 20.6 microg/g). Even when analyzing incisors alone, the Al concentrations were significantly higher in the sound tooth group than in the other groups, for both enamel and dentin. Furthermore, the Al levels in carious enamel and dentin did not decrease with the advance of caries. These findings indicated that the deciduous teeth containing higher Al concentrations on average had less caries than the teeth with lower Al concentrations, and suggest that Al acts as a possible cariostatic agent by itself.  相似文献   

14.
The capability of Nd:YAG laser in sterilizing root canals and the alterations of dentinal walls induced by laser treatment were investigated. Thirty root canals were infected by P. aeruginosa ATCC 27853 and thirty canals by A. naeslundii CH-12. Within each infection, 4 groups were selected on the basis of the treatment. Among them, 2 test groups (TGs) were treated by Nd:YAG laser at 15 Hz for 15 s, using 2 different settings: 1 Watt/70 Joule and 1.5 Watt/100 Joule, respectively (n = 10 each). The other 2 groups, used as controls (CGs), were: untreated (positive control, n = 5) and sterilized by 5.25% NaClO group (negative control, n = 5). Observations under scanning electron microscope (SEM) and quantitative bacterial counts were performed. These analyses were performed once per group after infections and treatments. Laser treatments significantly reduced the number of both bacteria. SEM investigation showed melting and crystallization of canal dentin over 1.5 W/100 J. Laser irradiation has a bactericidal effect but it does not completely sterilize the root canal as NaClO 5.25% solution does if the goal of treatment is also to avoid alterations of dentinal walls.  相似文献   

15.
The aim of this study is to investigate the influence of different etching times on demineralized dentin surface morphology using scanning electron microscopy and qualitative line microanalysis of chemical structure. Two sample groups, consisting of 30 first premolar teeth in each group, were established. Teeth were cut at the half-distance between the enamel-dentin junction and the pulp. The first group of specimens was etched for 10 seconds and the second group for 30 seconds. 37% ortophosphoric acid was used. SEM (scanning electron microscopy) was utilized to observe the following parameters: number and diameter of dentinal tubules, dentinal and intertubular dentinal surface percentage, appearance of the dentin surface porous zone containing smear layer and demineralized residual collagen particles with dentin demineralization products in acid globules, and dissolved peritubular dentin cuff. After calculating measurements of central tendency (X,C, Mo, SD), Kolmogorov-Smirnov and Student t-test were performed to confirm the quantitative results, and the chi2-test was run to produce qualitative data. In contrast to the 10-second etching time, the increased etching time of 30 seconds resulted in the following findings: (1) an increased number of dentinal tubules (p < 0.05), (2) an increase in dentinal tubule diameter (p < 0.05), (3) an increase in dentinal tubule surface percentage (p < 0.001), (4) a decrease in intertubular dentinal surface percentage (p < 0.001), (5) appearance of dentin surface porous zone containing smear layer and demineralized residual collagen particles with dentin demineralization products in acid globules (p < 0.001), and (6) completely dissolved peritubular dentin cuff (p <0.001). Therefore, different etching times using the same phosphoric acid concentration result in different morphological changes in demineralized dentin surface. Moreover, based on a comparison with current studies, prolonged etching time causes morphological changes to dentin surface. Such changes, have, in turn, negative effects on the dentin hybridization process.  相似文献   

16.
The exact mechanisms and enzymes involved in caries progression are largely unclear. Apoptosis plays a key role in dentin remodelling related to damage repair; however, it is unclear whether apoptosis in decayed teeth is activated through the extrinsic or the intrinsic pathway. This ex vivo immunohistochemical study explored the localization of TRAIL, DR5, Bcl-2 and Bax, the main proteins involved in apoptosis, in teeth with advanced caries. To evaluate TRAIL, DR5, Bcl-2 and Bax immunoexpressions twelve permanent carious premolars were embedded in paraffin and processed for immunohistochemistry. The results showed that TRAIL and DR5 were overexpressed in dentin and in pulp vessels and mononuclear cells; strong Bax immunostaining was detected in dilated dentinal tubules close to the lesion, and Bcl-2 staining was weak in some dentin areas under the cavity or altogether absent. These findings suggest that both apoptosis pathways are activated in dental caries. Further studies are required to gain insights into its biomolecular mechanisms.Key words: Apoptosis, TRAIL, DR5, Bax, Bcl-2, carious teeth  相似文献   

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