义齿清洁剂对树脂基托颜色的影响

目的：研究常用义齿清洁剂对树脂基托颜色的影响。方法：用四种常用的义齿清洁剂处理四种国内常用的基托树脂，用CS5电脑配色系统检测树脂颜色的变化。结果：不同树脂的颜色受不同清洁剂的影响不同，洁美清洁剂对登士柏热凝和日进热凝树脂的白度增加和色差较大；0.02％NaClO对日进自凝树脂的白度增加和色差较大；0.0125％NaClO和0.02％NaClO对上海自凝树脂的白度增加和色差较大。结论：洁美清洁剂对登士柏热凝和日进热凝树脂的颜色改变较明显，NaClO对日进自凝树脂和上海自凝树脂的颜色改变较明显。     

不同类型义齿清洁剂对热凝基托树脂物理机械性能的影响

目的：观察不同类型义齿清洁剂对热凝基托树脂物理机械性能的影响。方法：将同样规格的热凝基托树脂试件,按使用说明分别浸泡在 Polident 清洁片或 Steradent 清洁片或0．5％次氯酸钠溶液和蒸馏水中60 h,处理后的试件在万能材料试验机和表面粗糙度测试仪上分别测其弯曲强度、弹性模量（n ＝10）和表面粗糙度（n ＝10）。结果：Polident、Steradent 对热凝基托树脂的弯曲强度和弹性模量的影响与蒸馏水组相比差异无统计学意义（P ＞0．05）,0．5％次氯酸钠组的弯曲强度和弹性模量小于其他组（P ＜0．05）;热凝基托树脂粗糙度4组之间差异无统计学意义（P ＞0．05）。结论：Polident、Steradent 均不影响热凝基托树脂的物理机械性能,0．5％次氯酸钠对热凝基托树脂的粗糙度无影响,而使其弯曲强度及弹性模量有所降低。     

不同类型义齿清洁剂对基托树脂表面白色念珠菌抑菌效果观察

目的:不同类型义齿清洁剂对粘附在热凝基托树脂表面的白色念珠菌的抑制效果观察。方法:同样规格的热凝基托树脂试件浸泡于同一浓度白色念珠菌菌液中,按使用说明分别浸泡在Polident、Steradent清洁片配成的溶液、0.5%次氯酸钠溶液(阳性对照组)和蒸馏水(阴性对照组)中,将处理后试件上粘附的白色念珠菌培养后用分光光度计测定吸光度,比较不同处理方法对白色念珠菌的清除率。结果:0.5%次氯酸钠(0.04040±0.004742)优于Polident(0.06990±0.005990)优于Steradent(0.12390±0.005724)优于蒸馏水(1.21790±0.009585)。结论:Polident、Steradent对热凝基托树脂表面白色念珠菌均有明显的抑菌效果,但效果均不如阳性对照组。     

不同的清洁方法对着色树脂基托和人工牙的清洁效果的研究

目的:研究5种不同的清洁方法对着色树脂基托和人工牙的清洁效果。方法:将着色后的树脂基托和人工牙试件根据不同的清洁方式随机分成5组(n=10),A:对照组,B:电动牙刷+蒸馏水刷洗3 min, C:电动牙刷+牙膏刷洗3 min。D:Polident浸泡5 min。E:Polident浸泡5 min+电动牙刷牙膏刷洗3 min。计算清洁前后的色差ΔE以及着色前和清洁后的色差ΔE。结果:对于树脂基托和人工牙,着色前与着色后ΔE值组间比较,P>0.05。清洁前后各组ΔE比较：E>D>C>B>A(P<0.05),着色前和清洁后各组ΔE比较：E相似文献   

不同热凝义齿基托树脂对基托表面亲水性及力学性能的影响

目的 研究不同热凝义齿基托树脂对基托表面亲水性及力学性能的影响,以提高义齿基托的表面特性及弯曲特性的新思路和新方法。方法 选择平均分子量及平均粒径不同的4种粉剂：D-100M(甲基丙烯酸甲酯聚合物粉）,聚甲基丙烯酸甲酯聚合(D-250M）,聚甲基丙烯酸甲酯/丙烯酸乙酯共聚物(D-300）,聚甲基丙烯酸乙酯聚合物(D-250E）,作为研究对象,将各组粉剂和4种单体(MMA,i-BMA,EHMA,HEMA）分别配对聚合成15种不同材料的试件,进行周期性浸泡,随后置于恒温干燥箱0、14、30、90、180、360天后,测定表面接触角及弯曲性能。结果 浸泡前各组试件之间的差异有统计学意义(P<0.05）。浸泡后各材料之间的接触角变化显著不同;弯曲强度及弯曲弹性模量的差异有统计学意义(P<0.05）。随着时间推移,甲基丙烯酸甲酯组(MMA）的弯曲强度显著高于其他组(P<0.05）;单体MMA和EHMA+HEMA组浸泡至360天时弯曲强度无显著变化;其余组的样本浸泡至30天后弯曲强度明显上升。结论 适当组成成分的搭配对热凝义齿基托的表面亲水性、弯曲强度及弯曲弹性模量有很大影响,恰当的组合能改进热凝义齿基托的表面特性及力学性能。     

义齿清洁剂对着色拜耳牙洁美效果的研究

目的：评价义齿清洁剂对着色拜耳牙的洁美效果及清洁前后拜耳牙的色彩稳定性方法：将24颗21号色拜耳中切牙分为3组，分别用红酒、咖啡、绿茶浸泡染色4周后，用假牙洁美片浸泡去除着色，用电子比色仪测定各组样本着色前后及清洁后的L^*、a^*、b^*值，计算色差，并进行统计学分析。结果：3组拜耳牙在着色后均表现出具临床意义的显著色差，经义齿清洁剂清洁后，色差减小至可接受程度，结论：饮食中色素可影响拜耳牙的色彩稳定性，而义齿清洁剂对其沽美效果良好，值得肯定：     

机械清洁对基托树脂外源性着色的影响

目的:研究机械清洁方法即电动牙刷配合清洁膏、牙膏、自来水刷洗对基托树脂表面着色的影响。方法:制作64块热固化型基托树脂试件,取60块分为4组,每组15块,其中3组为实验组,1组为对照组。实验组试件分别用电动牙刷配合自来水、牙膏、清洁膏刷洗22min,对照组不做处理。每组试件再随机分成3组,分别浸泡入橙汁、药酒、漱口水中4周。于浸泡前后用电子比色仪测色,计算着色前后色差,与对照组进行比较,行统计学分析。另外的4块试件,1块作为对照,另3块分别用三种机械方法刷洗22min,扫描电镜观察各试件表面形态,比较三种清洁方法对热固化型树脂表面的磨损情况。结果:各浸泡液中牙膏刷洗组与对照组相比色差有统计学意义(P<0.05),其余均无统计学差异(P﹥0.05)。扫描电镜观察显示:空刷与清洁膏刷洗没有对基托表面形貌产生明显影响,而牙膏刷洗的树脂表面产生了一定程度的划痕。结论:电动牙刷配合自来水和清洁膏刷洗不会对热固化型基托树脂表面造成明显磨损,对于树脂表面色素的沉积均无明显影响。而电动牙刷配合牙膏刷洗对树脂表面有一定的磨损,且加重树脂的着色。     

不同基托树脂抗弯性能的比较

目的 为临床医生在基托树脂的选择上提供一个参考依据。方法 选用5种义齿基托材料，错成试件。在一定的实验条件下对试件加力，记录试件的断裂弯曲载荷。结果 不碎胶树脂断裂弯曲载荷最大，除常规热凝树脂组和BPS树脂组之间无显著性差异外，其余各组间均有显著性差异。结论 不碎胶基托树脂、BPS基托树脂和常规热凝树脂是较为理想的基托材料。大面积义齿基托不宜采用自凝和光聚合基托树脂。     

热固化基托树脂外源性着色的体外研究

目的评价5种食物、药物对热固化基托树脂着色的程度。方法制作90块热固化基托树脂试件,随机分为6组,分别浸泡于蒸馏水(对照)、绿茶、橙汁、漱口水、药酒和黄连水中,用电子比色仪测量树脂浸泡前及浸泡1、2、3、4周后的颜色,得到L*、a*、b*值,计算各时间点与浸泡前的色差ΔE,进行统计学分析。结果除对照组外,5组实验组试件的ΔE值(颜色改变)均随浸泡时间延长而增大;不同浸泡液中试件的ΔE值有显著性差异,其大小顺序为:黄连水>漱口水>绿茶>药酒>橙汁。结论绿茶、橙汁、漱口水、药酒和黄连水均可导致热固化基托树脂表面着色,尤以黄连水着色最重。且随着时间延长,基托树脂表面着色加重。     

热凝基托树脂的几种调制方法

根据我们多年的临床技工室操作经验，现将热凝基托树脂的调制方法作简要介绍，并对它们的使用方法和使用效果加以比较。     

An in vitro study into the effect of a limited range of denture cleaners on surface roughness and removal of Candida albicans from conventional heat-cured acrylic resin denture base material

This study evaluated the abrasiveness of four denture cleaners on the surface of denture base material and assessed their ability to remove Candida albicans. Acrylic resin discs 20 mm diameter and 2 mm thick were identically produced and polished. Four cleaners were evaluated: conventional toothpaste; toothpaste with stain remover; denture cleaning paste and an immersion type cleaner, and water were used as control. These were used at dilutions of 1:1, 1:2 and 1:3 with water. An electric toothbrush was used, and the discs cleaned to simulate 1 years' cleaning. The surface roughness of the discs were then measured, before and after cleaning, using a stylus profilometer, then inoculated with 1.2 x 10(6)C. albicans cells. The effectiveness of the denture cleaners to remove C. albicans cells was assessed following a single cleaning event. The immersion cleaner was significantly less abrasive than paste cleaners (P < 0.05). There were no significant differences between any dilutions for any cleaner used (P > 0.05). Immersion and paste cleaners removed almost all recoverable C. albicans from the discs, as cleaning with water alone was less effective (P < 0.05). An immersion type cleaner was found to be the most suitable cleaner because of its low abrasivity and effective removal of organic debris.     

Evaluation of staining susceptibility of resin artificial teeth and stain removal efficacy of denture cleansers

Objective. To assess the staining susceptibility of four acrylic resin (Ivostar, SR Vivodent PE, Major Dent, Integral) and a nanocomposite resin (Veracia) artificial teeth and to evaluate the stain removal efficacy of denture cleansers. Materials and methods. Sixty maxillary incisors of each brand (total = 300) were divided into three groups according to staining solution as coffee, red wine and tea. Baseline color measurements were performed with a spectrophotometer. Specimens were immersed in staining solutions for 14 h (2 h × 7 days) and then second color measurements were performed. Each group was further divided into four sub-groups according to denture cleanser as Corega tabs, Fittydent, NaOCl (0.5%) and distilled water (control) (n = 5). Specimens were immersed in denture cleansers for 8 h and third color measurements were made. Thus, the weekly simulation period was completed. This cycle was repeated 12 times to simulate a 3-month time period and measurements were performed at the end of the 4th, 8th and 12th cycles. ΔE values were calculated and data were analyzed with 3-way repeated measures ANOVA and Bonferroni tests. Results. Significant color differences were found among the teeth and staining solutions, but all of the color differences were in the clinically acceptable range (ΔE < 5.5). Integral showed the highest ΔE values for all solutions, while Ivostar and Vivodent demonstrated the lowest ΔE values for red wine and tea solutions. There was no significant difference among the denture cleansers in terms of stain removal efficacy. Conclusions. Cross-linked acrylic (Integral) and nanocomposite (Veracia) resin teeth were more susceptible to staining. Denture cleansers were efficient on stain removal from artificial teeth.     

着色介质及表面粗糙度对热固化基托树脂着色的影响

目的:研究4种着色介质对不同表面粗糙度的热固化基托树脂的表面着色状况。方法:制作64个热固化基托树脂试件,随机分成4组,不同组试件的测试面打磨出不同的粗糙度等级,用表面粗糙度轮廓仪测量其表面粗糙度参数Ra并记录,然后将每组试件分别浸泡于蒸馏水(对照)、咖啡、茶和陈醋中,用分光光度比色仪测量试件浸泡前及浸泡4周后的颜色,得到L*、a*、b*值,计算浸泡前后的色差△E,采用统计学方法,分析热固化基托树脂着色与上述因素的关系。结果:除对照组外,咖啡组和茶组试件的色差值△E均增大(P<0.05),且咖啡组的△E大于茶组(P<0.05),陈醋组的△E无明显改变(P>0.05);同一浸泡液中不同表面粗糙度的试件的△E值差异有显著性(P<0.05),表面粗糙度越大,△E越大。结论:外源性色素能引起基托树脂的着色,并且树脂表面越粗糙,着色越明显。     

Contact wear of artificial denture teeth

Purpose

High wear resistance of denture teeth preserves good occlusal relationship and sufficient parafunctional stability. This in-vitro investigation aimed to determine and compare the wear performance of different artificial denture teeth.

The effect of the addition of poly(methyl methacrylate) fibres on some properties of high strength heat-cured acrylic resin denture base material

The self-reinforcement of acrylic resin with butadiene styrene surface treated poly(methyl methacrylate) fibres has been reported to have the potential to substantially improve the transverse bend strength of conventional heat-cured acrylic resin. The aim of this study was to investigate the effect of the addition of butadiene styrene surface treated poly(methyl methacrylate) fibres in cross-ply arrangement to high impact acrylic resin on the transverse and impact strength. Specimens were prepared as specified in the International Standard Organization and British Standards for the Testing of Denture Base Resins (ISO 1567, 1988; BS 2487, 1989) and the British Standard Specification for Orthodontic resins (BS 6747, 1987) for transverse bend and impact testing. The impact strength was measured using a Zwick pendulum impact tester and the transverse bend strength measured using a Lloyds Instruments testing machine. The results showed that the impact strength was not improved with the addition of fibres, high impact acrylic resin with fibres (LF) 11.1 kJ m-2 and high impact acrylic resin (L) (12.5 kJ m-2). The modulus of rupture was decreased with the addition of fibres (57.8 MPa) for (LF) compared with (60.4 MPa) for (L). The modulus of elasticity was also reduced with the addition of fibres (1834.9 MPa) (LF) and 2086.2 MPa (L) as was the peak load (LF) (50.8 N) and (L) (55.8 N). It was concluded that the addition of surface treated poly(methyl methacrylate) fibres in cross-ply arrangement to high strength acrylic resin did not produce an improvement in the impact or transverse strength and cannot be recommended as a method of reinforcement.     

三种丙烯酸树脂牙和丙烯酸牙托粉的结合强度实验研究

为了探求人造牙从基托上脱落下来的原因,本文作者对三种丙烯酸树脂牙和三种丙烯酸牙托粉的拉伸结合强度和剪切结合强度进行了测试,结果表明,材料和不同品牌材料的匹配都会影响人造牙与基托的结合强度;塑料牙盖嵴面打磨粗糙后,可显著增强塑料牙与基托树脂的结合强度。     

Shear bond strength of resin teeth to heat-cured and light-cured denture base resin

The failure of the bond between acrylic resin teeth and denture base material remains a considerable problem. Previous research has indicated that the introduction of a bonding agent to the tooth-resin interface significantly increased the tensile bond strength. To further investigate this finding, and to complement the earlier study, a shear strength assessment was carried out. Both a commercial and an experimental bonding agent were evaluated for tooth retention when applied to heat-cured and visible light-cured (VLC) resin. A significant increase in shear bond strength was obtained when bonding agents were applied. The experimental cement gave the greatest increase in strength, although the VLC resin failed to achieve the same degree of tooth attachment as the heat-cured resin.     

Comparative bond strengths of autopolymerising denture resin and light cured composite resin to denture teeth

AIM: To investigate the shear bond strengths between light cured composite and autopolymerised acrylic resin bonded to acrylic resin denture teeth. METHODS: Surface treatments were used for the denture teeth included wetting with methylmethacrylate (MMA) monomer, composite bonding agent and acid etching. The samples were divided into seven groups. Two groups of specimens were immersed in distilled water for 30 days to hydrate the teeth. Five other groups of embedded denture teeth were stored in air at room temperature for 30 days. RESULTS: Analysis of variance indicated statistically significant differences between groups (P < 0.001). CONCLUSION: The greatest bond strengths to denture teeth were in acrylic resins polymerised with pressure and wetted with monomer. The bond strengths of hydrated and unhydrated samples gave similar results both with acrylic resins and composites.