Porcelain laminate veneers have been a common treatment strategy in dental clinics. It is a conservative method for treatment of esthetic and functional problems in anterior region of oral cavity. Wide range of dental...Porcelain laminate veneers have been a common treatment strategy in dental clinics. It is a conservative method for treatment of esthetic and functional problems in anterior region of oral cavity. Wide range of dental ceramics is now available on market for fabrication of laminate veneers. Clinician should have enough knowledge regarding the composition and properties of these materials in order to be able to choose the appropriate one according to clinical situations.展开更多
Objective:To evaluate the shear bond strength(SBS) between alumina-toughened zirconia (ATZ) cores and veneering ceramics,investigate the effect of aging in artificial saliva on SBS and compare it with that of yttria-s...Objective:To evaluate the shear bond strength(SBS) between alumina-toughened zirconia (ATZ) cores and veneering ceramics,investigate the effect of aging in artificial saliva on SBS and compare it with that of yttria-stabilized tetragonal zirconia polycrystals(Y-TZP).Methods:Bars of ATZ and Y-TZP were layered with veneering ceramics in accordance to the recommendation of the manufacturer.Half of each group(n = 10) was aged at 134℃.(under 2 bar pressure) in an autoclave for 48 h.Subsequently,all specimens were subjected to shear force in a universal testing machine.The interface and fractured surface of the specimens were evaluated using scanning electron microscopy and X-ray energy dispersive spectroscopy.Results:The initial mean SBS values in MPa±SD were 28.9±8.0 for ATZ and 26.2±7.6 for Y-TZP.After aging,the mean SBS values for ATZ and Y-TZP were 22.9±4.9 MPa and 22.8±6.9 MPa,respectively.Neither the differences between the SBS values of the ATZ and Y-TZP groups nor the influence of aging on all groups were statistically significant.Conclusions:The SBS between the ATZ core and the veneering ceramics was not affected by aging.The SBS of ATZ to veneering ceramics was not significantly different compared with that of Y-TZP.展开更多
Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip steel.In order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultr...Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip steel.In order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultra-thin strip,ABAQUS finite element model calculation,3D laser profilometry,and other methods were adopted based on the physical characteristics of Si_(3)N_(4) ceramic roll and 9Cr2MoV steel roll,like anti-flattening performance and oil wettability.The surface morphology and roughness of SUS304 ultra-thin strip rolled by different material work rolls under oil lubrication conditions were measured.The results showed that under the rolling force of 10 kN,the maximum flattening amount of Si_(3)N_(4) ceramic roll was reduced by 35.14%compared to that of 9Cr2MoV steel roll.The reduction rate of SUS304 ultra-thin strip rolled by ceramic roll was 34.19%,while that rolled by steel roll was only 22%;Si_(3)N_(4) ceramic roll can further increase the number of alternating convex peaks and concave valleys in the rolled thin strip,reduce the profile steepness,reduce surface roughness,and enhance the planarization effect of surface micro-convex bodies,with improving surface quality and surface glossiness.Finally,the mechanism of Si_(3)N_(4) ceramic roll significantly improving the surface roughness of rolled SUS304 ultra-thin strip was proposed.展开更多
目的:探讨微创全瓷贴面配合数字化微笑设计(Digital smile design,DSD)技术修复前牙切缘切角缺损的美学效果。方法:选取2019年1月-2022年1月笔者医院接诊的78例前牙切缘切角缺损患者为研究对象,采用区组随机化法分为观察组(116颗患牙)...目的:探讨微创全瓷贴面配合数字化微笑设计(Digital smile design,DSD)技术修复前牙切缘切角缺损的美学效果。方法:选取2019年1月-2022年1月笔者医院接诊的78例前牙切缘切角缺损患者为研究对象,采用区组随机化法分为观察组(116颗患牙)和对照组(120颗患牙),每组39例。对照组采用微创全瓷贴面修复,观察组给予微创全瓷贴面联合DSD技术进行修复。比较两组患者治疗6个月后的满意度、美学效果[美国公共卫生署评估标准(United states public health service,USPHS)],对比治疗前后两组患者的红色美学指数、牙周健康指数[牙龈指数(Gingival index,GI)、牙菌斑指数(Plaque index,PLI)、龈沟出血指数(Sulcus bleeding index,SBI)]的变化。结果:治疗6个月后,两组美学效果各维度评级有显著差异,观察组治疗满意率、红色美学指数评分均显著高于对照组(P<0.05);治疗6个月后,两组GI、PLI、SBI均明显降低,且观察组显著低于对照组(P<0.05)。结论:微创全瓷贴面联合DSD技术修复前牙切缘切角缺损可有效改善牙齿美学效果,提高患者治疗满意度,适合临床推广。展开更多
目的探讨树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复老年脑卒中病人短冠磨牙的疗效。方法收集研究2018年3月至2021年10月北京市大兴区医院老年脑卒中短冠磨牙病人124例,根据修复方案分为两组,采用紫荆氧化锆全瓷冠修复治疗的61例病人...目的探讨树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复老年脑卒中病人短冠磨牙的疗效。方法收集研究2018年3月至2021年10月北京市大兴区医院老年脑卒中短冠磨牙病人124例,根据修复方案分为两组,采用紫荆氧化锆全瓷冠修复治疗的61例病人为对照组,采用树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复治疗的63例为观察组。采用改良美国公共卫生机构(United States public health service,USPHS)标准比较两组修复后6、12个月修复效果、微渗漏分级、并发症发生率、修复前、修复后12个月口腔健康影响程度量表中文版(OHIP-14)评分及修复后12个月李克特量表(Likert scale)评分。结果修复效果:修复后12个月观察组边缘密合度、颜色匹配度、修复体折裂、牙体完整性、继发龋合格率分别为93.65%(59/63)、93.65%(59/63)、96.83%(61/63)、96.83%(61/63)、95.24%(60/63),均高于对照组[80.33%(49/61)、81.97%(50/61)、83.61%(51/61)、81.97%(50/61)、83.61%(51/61)](P<0.05);微渗漏分级:两组修复后6、12个月微渗漏分级比较,差异无统计学意义(P>0.05);并发症:观察组并发症发生率3.17%(2/63)低于对照组14.75%(9/61)(P<0.05);口腔健康相关生活质量:修复后12个月观察组OHIP-14量表功能限制、生理疼痛、心理不适、生理障碍、心理障碍、社交障碍评分分别为(1.89±0.57)分、(2.03±0.62)分、(0.92±0.30)分、(0.53±0.18)分、(0.42±0.10)分、(0.63±0.25)分,均低于对照组[(2.55±0.74)分、(2.73±0.88)分、(1.29±0.27)分、(0.74±0.26)分、(0.31±0.13)分、(0.89±0.20)分](P<0.05);修复效果满意度:修复后12个月观察组修复效果自我评估、并发症满意度、生活质量满意度评分依次为(4.62±0.39)分、(4.25±0.44)分、(4.57±0.40)分,均高于对照组[(4.12±0.35)分、(3.86±0.35)分、(4.03±0.46)分](P<0.05)。结论树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复应用于老年脑卒中病人短冠磨牙,修复效果良好,有助于降低并发症发生率,提高口腔健康相关生活质量,改善修复效果满意度。展开更多
目的 本实验采用Er:Yag激光对不同厚度、不同材质[牙合]贴面进行体外照射去粘接,通过分析比较Er:Yag激光对于[牙合]贴面、牙体组织微观结构的影响,为激光无创拆除[牙合]贴面提供理论依据。方法 选取新鲜拔除正畸下颌前磨牙,标准化牙体...目的 本实验采用Er:Yag激光对不同厚度、不同材质[牙合]贴面进行体外照射去粘接,通过分析比较Er:Yag激光对于[牙合]贴面、牙体组织微观结构的影响,为激光无创拆除[牙合]贴面提供理论依据。方法 选取新鲜拔除正畸下颌前磨牙,标准化牙体预备后制作3种不同厚度(1.0、1.5、2.0 mm)和不同材质(Vita琥珀瓷、Vita MarkⅡ、润瓷)[牙合]贴面进行粘接,1周后使用Er:Yag激光(2.5、3.5 W)照射[牙合]贴面并记录时间。扫描电镜(SEM)观察去除后的微观形态。结果 润瓷[牙合]贴面经2.5或3.5 W Er:Yag激光长时间(>20 min)照射后仍无法取下;2.5 W Er:Yag激光去除粘接时间:1.0 mm Vita琥珀瓷组(96.0 s±16.0 s)大于1.0 mm Vita MarkⅡ组(84.5 s±19.5s)(P<0.05);1.5mm Vita琥珀瓷组(246.5s±13.5s)大于1.5mm VitaMarkⅡ组(170.0s±14.0s)(P<0.05);3.5 W Er:Yag激光去除粘接时间:2.0 mm Vita琥珀瓷组(381.0 s±24.0 s)大于2.0 mm Vita MarkⅡ组(341.5 s±26.5 s)。结论 同种材质、相同厚度情况下:激光功率越大,拆除时间越短,当功率较小时,可能导致[牙合]贴面无法拆除。相同厚度、相同功率情况下:激光穿透瓷块到达粘接层可能对瓷块结构产生影响。同种材料、相同功率情况下:瓷块厚度越厚,拆除所需时间越长,所需功率越高。激光无法直接拆除树脂类[牙合]贴面。展开更多
文摘Porcelain laminate veneers have been a common treatment strategy in dental clinics. It is a conservative method for treatment of esthetic and functional problems in anterior region of oral cavity. Wide range of dental ceramics is now available on market for fabrication of laminate veneers. Clinician should have enough knowledge regarding the composition and properties of these materials in order to be able to choose the appropriate one according to clinical situations.
基金supported by National High-Tech Research and Development Program of China(863 Program)(No.2006AA03Z440)
文摘Objective:To evaluate the shear bond strength(SBS) between alumina-toughened zirconia (ATZ) cores and veneering ceramics,investigate the effect of aging in artificial saliva on SBS and compare it with that of yttria-stabilized tetragonal zirconia polycrystals(Y-TZP).Methods:Bars of ATZ and Y-TZP were layered with veneering ceramics in accordance to the recommendation of the manufacturer.Half of each group(n = 10) was aged at 134℃.(under 2 bar pressure) in an autoclave for 48 h.Subsequently,all specimens were subjected to shear force in a universal testing machine.The interface and fractured surface of the specimens were evaluated using scanning electron microscopy and X-ray energy dispersive spectroscopy.Results:The initial mean SBS values in MPa±SD were 28.9±8.0 for ATZ and 26.2±7.6 for Y-TZP.After aging,the mean SBS values for ATZ and Y-TZP were 22.9±4.9 MPa and 22.8±6.9 MPa,respectively.Neither the differences between the SBS values of the ATZ and Y-TZP groups nor the influence of aging on all groups were statistically significant.Conclusions:The SBS between the ATZ core and the veneering ceramics was not affected by aging.The SBS of ATZ to veneering ceramics was not significantly different compared with that of Y-TZP.
基金supported by the National Natural Science Foundation of China (No.51974196)the Major Program of National Natural Science Foundation of China (No.U22A20188)Central Government Guides the Special Fund Projects of Local Scientific and Technological Development (YDZX20191400002149).
文摘Surface morphology and roughness are important parameters of surface quality of cold-rolled ultra-thin strip steel.In order to study the effect of Si_(3)N_(4) ceramic work rolls on the surface roughness of SUS304 ultra-thin strip,ABAQUS finite element model calculation,3D laser profilometry,and other methods were adopted based on the physical characteristics of Si_(3)N_(4) ceramic roll and 9Cr2MoV steel roll,like anti-flattening performance and oil wettability.The surface morphology and roughness of SUS304 ultra-thin strip rolled by different material work rolls under oil lubrication conditions were measured.The results showed that under the rolling force of 10 kN,the maximum flattening amount of Si_(3)N_(4) ceramic roll was reduced by 35.14%compared to that of 9Cr2MoV steel roll.The reduction rate of SUS304 ultra-thin strip rolled by ceramic roll was 34.19%,while that rolled by steel roll was only 22%;Si_(3)N_(4) ceramic roll can further increase the number of alternating convex peaks and concave valleys in the rolled thin strip,reduce the profile steepness,reduce surface roughness,and enhance the planarization effect of surface micro-convex bodies,with improving surface quality and surface glossiness.Finally,the mechanism of Si_(3)N_(4) ceramic roll significantly improving the surface roughness of rolled SUS304 ultra-thin strip was proposed.
文摘目的:探讨微创全瓷贴面配合数字化微笑设计(Digital smile design,DSD)技术修复前牙切缘切角缺损的美学效果。方法:选取2019年1月-2022年1月笔者医院接诊的78例前牙切缘切角缺损患者为研究对象,采用区组随机化法分为观察组(116颗患牙)和对照组(120颗患牙),每组39例。对照组采用微创全瓷贴面修复,观察组给予微创全瓷贴面联合DSD技术进行修复。比较两组患者治疗6个月后的满意度、美学效果[美国公共卫生署评估标准(United states public health service,USPHS)],对比治疗前后两组患者的红色美学指数、牙周健康指数[牙龈指数(Gingival index,GI)、牙菌斑指数(Plaque index,PLI)、龈沟出血指数(Sulcus bleeding index,SBI)]的变化。结果:治疗6个月后,两组美学效果各维度评级有显著差异,观察组治疗满意率、红色美学指数评分均显著高于对照组(P<0.05);治疗6个月后,两组GI、PLI、SBI均明显降低,且观察组显著低于对照组(P<0.05)。结论:微创全瓷贴面联合DSD技术修复前牙切缘切角缺损可有效改善牙齿美学效果,提高患者治疗满意度,适合临床推广。
文摘目的探讨树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复老年脑卒中病人短冠磨牙的疗效。方法收集研究2018年3月至2021年10月北京市大兴区医院老年脑卒中短冠磨牙病人124例,根据修复方案分为两组,采用紫荆氧化锆全瓷冠修复治疗的61例病人为对照组,采用树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复治疗的63例为观察组。采用改良美国公共卫生机构(United States public health service,USPHS)标准比较两组修复后6、12个月修复效果、微渗漏分级、并发症发生率、修复前、修复后12个月口腔健康影响程度量表中文版(OHIP-14)评分及修复后12个月李克特量表(Likert scale)评分。结果修复效果:修复后12个月观察组边缘密合度、颜色匹配度、修复体折裂、牙体完整性、继发龋合格率分别为93.65%(59/63)、93.65%(59/63)、96.83%(61/63)、96.83%(61/63)、95.24%(60/63),均高于对照组[80.33%(49/61)、81.97%(50/61)、83.61%(51/61)、81.97%(50/61)、83.61%(51/61)](P<0.05);微渗漏分级:两组修复后6、12个月微渗漏分级比较,差异无统计学意义(P>0.05);并发症:观察组并发症发生率3.17%(2/63)低于对照组14.75%(9/61)(P<0.05);口腔健康相关生活质量:修复后12个月观察组OHIP-14量表功能限制、生理疼痛、心理不适、生理障碍、心理障碍、社交障碍评分分别为(1.89±0.57)分、(2.03±0.62)分、(0.92±0.30)分、(0.53±0.18)分、(0.42±0.10)分、(0.63±0.25)分,均低于对照组[(2.55±0.74)分、(2.73±0.88)分、(1.29±0.27)分、(0.74±0.26)分、(0.31±0.13)分、(0.89±0.20)分](P<0.05);修复效果满意度:修复后12个月观察组修复效果自我评估、并发症满意度、生活质量满意度评分依次为(4.62±0.39)分、(4.25±0.44)分、(4.57±0.40)分,均高于对照组[(4.12±0.35)分、(3.86±0.35)分、(4.03±0.46)分](P<0.05)。结论树脂纳米陶瓷Lava Ultimate髓腔内固位冠修复应用于老年脑卒中病人短冠磨牙,修复效果良好,有助于降低并发症发生率,提高口腔健康相关生活质量,改善修复效果满意度。
文摘目的 本实验采用Er:Yag激光对不同厚度、不同材质[牙合]贴面进行体外照射去粘接,通过分析比较Er:Yag激光对于[牙合]贴面、牙体组织微观结构的影响,为激光无创拆除[牙合]贴面提供理论依据。方法 选取新鲜拔除正畸下颌前磨牙,标准化牙体预备后制作3种不同厚度(1.0、1.5、2.0 mm)和不同材质(Vita琥珀瓷、Vita MarkⅡ、润瓷)[牙合]贴面进行粘接,1周后使用Er:Yag激光(2.5、3.5 W)照射[牙合]贴面并记录时间。扫描电镜(SEM)观察去除后的微观形态。结果 润瓷[牙合]贴面经2.5或3.5 W Er:Yag激光长时间(>20 min)照射后仍无法取下;2.5 W Er:Yag激光去除粘接时间:1.0 mm Vita琥珀瓷组(96.0 s±16.0 s)大于1.0 mm Vita MarkⅡ组(84.5 s±19.5s)(P<0.05);1.5mm Vita琥珀瓷组(246.5s±13.5s)大于1.5mm VitaMarkⅡ组(170.0s±14.0s)(P<0.05);3.5 W Er:Yag激光去除粘接时间:2.0 mm Vita琥珀瓷组(381.0 s±24.0 s)大于2.0 mm Vita MarkⅡ组(341.5 s±26.5 s)。结论 同种材质、相同厚度情况下:激光功率越大,拆除时间越短,当功率较小时,可能导致[牙合]贴面无法拆除。相同厚度、相同功率情况下:激光穿透瓷块到达粘接层可能对瓷块结构产生影响。同种材料、相同功率情况下:瓷块厚度越厚,拆除所需时间越长,所需功率越高。激光无法直接拆除树脂类[牙合]贴面。
