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 ...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.展开更多
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)lase...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.展开更多
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...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.展开更多
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 e...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.展开更多
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 ...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.展开更多
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 vitr...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.展开更多
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...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.展开更多
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 ...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.展开更多
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 ...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.展开更多
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...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。展开更多
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...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。展开更多
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...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。展开更多
文摘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.
基金supported by the Japan Society for the Promotion of Science,Grants-in-Aid for Scientific Research Fundamental Research(C)19K10161.
文摘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.
文摘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.
基金We thank the National Key R&D Program of China(No.2020YFA0710401)the National Natural Science Foundation of China(Nos.82225012,81922019,82071161,81991505,22122207,21988102,and 52075138)+1 种基金the Young Elite Scientist Sponsorship Program by CAST(No.2020QNRC001)the Beijing Nova Program(No.211100002121013).
文摘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.
文摘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.
文摘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.
文摘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.
基金the financial support from the National Natural Science Foundation of China (No. 51372005)
文摘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.
文摘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.
文摘目的: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。
文摘目的: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。
文摘目的: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。
