To investigate the corrosion behaviors and antibacterial effects of sodium hypochlorite(NaClO)and hydrogen peroxide silver ion(HPSI)disinfectants with different concentrations against dental unit waterlines and provid...To investigate the corrosion behaviors and antibacterial effects of sodium hypochlorite(NaClO)and hydrogen peroxide silver ion(HPSI)disinfectants with different concentrations against dental unit waterlines and provide guidance and reference for the use of chemical disinfectants,polyurethane tubes were immersed in ultrapure water(control group),0.1%NaClO,0.5%NaClO,1.0%NaClO,2.5%HPSI,5.0%HPSI,and 10%HPSI solutions for 6,12,and 18 weeks.Contact angles and Fourier transform infrared spectra were detected.Surface morphologies were observed using scanning electron microscopy and antibacterial activity was evaluated using Gram-positive Staphylococcus aureus(S.aureus).The results showed that sodium hypochlorite and hydrogen peroxide silver ion disinfectants presented good antibacterial activity against S.aureus.However,sodium hypochlorite could cause serious damage to the water pipes where corrosion pits and cracks were observed,and increasing the concentration of sodium hypochlorite could accelerate the corrosion process.Hydrogen peroxide silver ion disinfectants had no obvious damage to the water pipes.Therefore,hydrogen peroxide silver ion disinfectants are recommended to use for controlling bacterial infection in dental unit waterlines which can reduce the damage to the water pipes.展开更多
The purpose of our study was to evaluate the effect of photodynamic therapy （PDT）, using erythrosine as a photosensitizing agent and a dental halogen curing unit as a light source, on Streptococcus mutans in a biofi...The purpose of our study was to evaluate the effect of photodynamic therapy （PDT）, using erythrosine as a photosensitizing agent and a dental halogen curing unit as a light source, on Streptococcus mutans in a biofilm phase. The S. mutans biofilms were formed in a 24-well cell culture cluster. Test groups consisted of biofilms divided into four groups： group 1： no photosensitizer or light irradiation treatment （control group）; group 2： photosensitizer treatment alone; group 3： light irradiation alone; group 4： photosensitizer treatment and light irradiation. After treatments, the numbers of colony-forming unit （CFU） were counted and samples were examined by confocal laser scanning fluorescence microscopy （CLSM）. Only group 4 （combined treatment） resulted in significant increases in cell death, with rates of 75% and 55% after 8 h of incubation, and 74% and 42% at 12 h, for biofilms formed in brain-heart infusion （BHI） broth supplemented with 0% or O. 1% sucrose, respectively. Therefore, PDT of S. mutans biofilms using a combination of erythrosine and a dental halogen curing unit, both widely used in dental clinics, resulted in a significant increase in cell death. The PDT effects are decreased in biofilms that form in the presence of sucrose.展开更多
The damage effects of water sorption on the mechanical properties of the hydroxyapatite particle reinforced Bis-GMA/TEGDMA copolymer （HA/Bis-GMA/TEGDMA） h-ave been predicted using 3D finite cell models. The plastici...The damage effects of water sorption on the mechanical properties of the hydroxyapatite particle reinforced Bis-GMA/TEGDMA copolymer （HA/Bis-GMA/TEGDMA） h-ave been predicted using 3D finite cell models. The plasticizer effect on the polymer matrix was considered as a variation of its Young＇s modulus. Three different cell models were used to determine the influence of varying particle contents, interphase strength and moisture concentration on the debonding damage. The stress distribution pattern has been examined and the stress transfer mode clarified. The Young＇s modulus and fracture strength of the Bis-GMA/TEGDMA composite were also predicted using the model with and without consideration of the damage. ine Iormer results with consideration of the debonding damage are in good agreement with existing literature experimental data. The shielding effect of our proposed model and an alternative approach were discussed. The FCC cell model has also been extended to predict the critical load for the damaged and the undamaged composite subject to the 3-point flexural test.展开更多
目的评价集成式微酸性次氯酸溶液对口腔综合治疗台水路系统(dental unit water lines,DUWLs)的持续消毒效果。方法以储水瓶定期人工配置含氯消毒液消毒DUWLs为对照组,以集成式微酸性次氯酸溶液(非电解,有效氯浓度为10 mg/L)持续消毒DUWL...目的评价集成式微酸性次氯酸溶液对口腔综合治疗台水路系统(dental unit water lines,DUWLs)的持续消毒效果。方法以储水瓶定期人工配置含氯消毒液消毒DUWLs为对照组,以集成式微酸性次氯酸溶液(非电解,有效氯浓度为10 mg/L)持续消毒DUWLs为实验组,采集口腔科4个功能区50台口腔综合治疗台的水源水、管路水(椅位前水)、椅位水(漱口、高速、三用枪)及末端水出水口水样,对比2种消毒方式细菌菌落计数。结果实验组的水路水(椅位前水)、椅位水的细菌微生物计数检测合格率为100.0%,高于对照组的60%,差异有统计学意义(P<0.05);实验组诊疗椅的高速水、三用枪水、漱口水的细菌微生物计数检测合格率(100.0%)高于对照组(43.8%),差异有统计学意义(P<0.05);结论口腔综合治疗台水路中存在微生物污染,使用微酸性次氯酸溶液(非电解,有效氯浓度为10 mg/L)持续消毒的有效性、高效性、稳定性和持续性效果明显,但对致病菌和生物膜的消毒效果还需进行更深入的研究。展开更多
牙科综合治疗台水路(dental unit waterline,DUWL)的主要功能是在治疗过程中为手机和三用枪等设备提供治疗用水,起冲洗和冷却作用。DUWL由狭窄、细长的管道组成,易被污染导致生物膜形成。定植于DUWL中的病原菌可随水流进入患者口腔,或...牙科综合治疗台水路(dental unit waterline,DUWL)的主要功能是在治疗过程中为手机和三用枪等设备提供治疗用水,起冲洗和冷却作用。DUWL由狭窄、细长的管道组成,易被污染导致生物膜形成。定植于DUWL中的病原菌可随水流进入患者口腔,或通过由超声洁牙机、高速涡轮手机产生的气溶胶被患者或医务人员吸入呼吸道,从而增加牙科治疗感染的危险性。因此,DUWL污染被认为是导致牙科交叉感染的重要途径之一,并引起广泛关注。近年来,关于DUWL污染及对策已有大量研究,本文就其污染的影响因素、污染病原菌种类以及DUWL污染的对策作一综述。展开更多
基金Funded by the Xuhui District Medical Research Project(No.SHXH201913)the Clinical Research on Health Industry of Shanghai Municipal Health Commission(No.202040085)+1 种基金the Shanghai Medical Key Specialty(No.ZK2019B12)the National Natural Science Foundation of China(No.32000945)。
文摘To investigate the corrosion behaviors and antibacterial effects of sodium hypochlorite(NaClO)and hydrogen peroxide silver ion(HPSI)disinfectants with different concentrations against dental unit waterlines and provide guidance and reference for the use of chemical disinfectants,polyurethane tubes were immersed in ultrapure water(control group),0.1%NaClO,0.5%NaClO,1.0%NaClO,2.5%HPSI,5.0%HPSI,and 10%HPSI solutions for 6,12,and 18 weeks.Contact angles and Fourier transform infrared spectra were detected.Surface morphologies were observed using scanning electron microscopy and antibacterial activity was evaluated using Gram-positive Staphylococcus aureus(S.aureus).The results showed that sodium hypochlorite and hydrogen peroxide silver ion disinfectants presented good antibacterial activity against S.aureus.However,sodium hypochlorite could cause serious damage to the water pipes where corrosion pits and cracks were observed,and increasing the concentration of sodium hypochlorite could accelerate the corrosion process.Hydrogen peroxide silver ion disinfectants had no obvious damage to the water pipes.Therefore,hydrogen peroxide silver ion disinfectants are recommended to use for controlling bacterial infection in dental unit waterlines which can reduce the damage to the water pipes.
基金supported by Cooperative Research (CR1102) of Gangneung-Wonju National University Dental Hospital
文摘The purpose of our study was to evaluate the effect of photodynamic therapy （PDT）, using erythrosine as a photosensitizing agent and a dental halogen curing unit as a light source, on Streptococcus mutans in a biofilm phase. The S. mutans biofilms were formed in a 24-well cell culture cluster. Test groups consisted of biofilms divided into four groups： group 1： no photosensitizer or light irradiation treatment （control group）; group 2： photosensitizer treatment alone; group 3： light irradiation alone; group 4： photosensitizer treatment and light irradiation. After treatments, the numbers of colony-forming unit （CFU） were counted and samples were examined by confocal laser scanning fluorescence microscopy （CLSM）. Only group 4 （combined treatment） resulted in significant increases in cell death, with rates of 75% and 55% after 8 h of incubation, and 74% and 42% at 12 h, for biofilms formed in brain-heart infusion （BHI） broth supplemented with 0% or O. 1% sucrose, respectively. Therefore, PDT of S. mutans biofilms using a combination of erythrosine and a dental halogen curing unit, both widely used in dental clinics, resulted in a significant increase in cell death. The PDT effects are decreased in biofilms that form in the presence of sucrose.
基金Project supported by the Research Committee of the Hong Kong Polytechnic University (No.G-U042).
文摘The damage effects of water sorption on the mechanical properties of the hydroxyapatite particle reinforced Bis-GMA/TEGDMA copolymer （HA/Bis-GMA/TEGDMA） h-ave been predicted using 3D finite cell models. The plasticizer effect on the polymer matrix was considered as a variation of its Young＇s modulus. Three different cell models were used to determine the influence of varying particle contents, interphase strength and moisture concentration on the debonding damage. The stress distribution pattern has been examined and the stress transfer mode clarified. The Young＇s modulus and fracture strength of the Bis-GMA/TEGDMA composite were also predicted using the model with and without consideration of the damage. ine Iormer results with consideration of the debonding damage are in good agreement with existing literature experimental data. The shielding effect of our proposed model and an alternative approach were discussed. The FCC cell model has also been extended to predict the critical load for the damaged and the undamaged composite subject to the 3-point flexural test.
文摘目的评价集成式微酸性次氯酸溶液对口腔综合治疗台水路系统(dental unit water lines,DUWLs)的持续消毒效果。方法以储水瓶定期人工配置含氯消毒液消毒DUWLs为对照组,以集成式微酸性次氯酸溶液(非电解,有效氯浓度为10 mg/L)持续消毒DUWLs为实验组,采集口腔科4个功能区50台口腔综合治疗台的水源水、管路水(椅位前水)、椅位水(漱口、高速、三用枪)及末端水出水口水样,对比2种消毒方式细菌菌落计数。结果实验组的水路水(椅位前水)、椅位水的细菌微生物计数检测合格率为100.0%,高于对照组的60%,差异有统计学意义(P<0.05);实验组诊疗椅的高速水、三用枪水、漱口水的细菌微生物计数检测合格率(100.0%)高于对照组(43.8%),差异有统计学意义(P<0.05);结论口腔综合治疗台水路中存在微生物污染,使用微酸性次氯酸溶液(非电解,有效氯浓度为10 mg/L)持续消毒的有效性、高效性、稳定性和持续性效果明显,但对致病菌和生物膜的消毒效果还需进行更深入的研究。
文摘牙科综合治疗台水路(dental unit waterline,DUWL)的主要功能是在治疗过程中为手机和三用枪等设备提供治疗用水,起冲洗和冷却作用。DUWL由狭窄、细长的管道组成,易被污染导致生物膜形成。定植于DUWL中的病原菌可随水流进入患者口腔,或通过由超声洁牙机、高速涡轮手机产生的气溶胶被患者或医务人员吸入呼吸道,从而增加牙科治疗感染的危险性。因此,DUWL污染被认为是导致牙科交叉感染的重要途径之一,并引起广泛关注。近年来,关于DUWL污染及对策已有大量研究,本文就其污染的影响因素、污染病原菌种类以及DUWL污染的对策作一综述。
