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。     

4种义齿基托树脂力学性能比较

目的 :比较 4种义齿基托树脂的力学性能 ,为临床选择材料提供指导。方法 :按临床制作义齿的步骤制备试样 ,在材料试验机上测定材料的冲击强度、弯曲强度、弹性模量和布氏硬度 ,描绘弯曲试验的应力 应变曲线 ,并对断面进行显微分析。结果 :4种义齿基托树脂 (上海珊瑚、山西长治、Luciton199、Meliodent)的冲击强度分别为 (9.94± 2 .2 5)kJ/m2 、(6.55± 1.85)kJ/m2 、(13 .76± 4.3 1)kJ/m2 、(13 .70± 3 .71)kJ/m2 ,弯曲强度分别为 (75.2 7± 3 .2 4)MPa、(78.88± 7.66)MPa、(80 .47± 3 .2 7)MPa、(76.72± 3 .14 )MPa ,弹性模量分别为 (3 .0 8± 0 .15)GPa、(2 .96± 0 .10 )GPa、(2 .63± 0 .11)GPa、(2 .56± 0 .12 )GPa ,布氏硬度分别为(2 4.15± 1.3 4 )kg/mm2 、(2 3 .43± 1.65)kg/mm2 、(2 0 .86± 1.2 6)kg/mm2 、(18.49± 1.71)kg/mm2 。结论 :4种基托树脂材料相比 ,”上海珊瑚”和”山西长治”基托树脂硬而脆 ,Luciton 199基托树脂硬而强 ,Meliodent基托树脂硬而韧     

表面处理对义齿基托修理弯曲强度的影响

目的：观察义齿基托树脂断面丙酮化学处理对树脂粘接修理后的弯曲强度的影响。方法：制作４８个６５ｍｍ×１０ｍｍ×２.５ｍｍＰＭＭＡ热凝树脂试样,进行上三点弯曲试验,将压断后的试样随机分为６组,断面经常规预备后采用三种表面处理 方法：无处理、ＭＭＡ单体涂刷３０ｓ、丙酮涂刷３０ｓ,分别用自凝和热凝树脂修理,然后在材料试验机上测定其弯曲强度。结果：丙酮处理热凝树脂修理组和自凝树脂修理组的弯曲强度高于同种树脂修理的无处理组和ＭＭＡ处理组（Ｐ＜０．０１）,丙酮处理热凝树脂修理组的弯曲强度最高,其强度恢复率为达９４．１４％;自凝和热凝树脂修理其弯曲强度无处理组和ＭＭＡ处理组无显著性差别（Ｐ＞０．０５）,其强度恢复率为原来的５０％～６０％。结论：丙酮化学处理树脂断面可提高义齿基托修理后的抗弯强度。     

氧化锌晶须填料对义齿基托树脂力学性能的影响

目的：研究添加氧化锌晶须对基托树脂力学性能的影响。方法：将氧化锌晶须按不同的质量百分比加人基托粉中,分为空白对照组、1％、3％、5％、7％等5组。根据ISO标准测试各组的力学性能,并对试样断面进行扫描电镜观察。结果：随着氧化锌晶须用量的增加,复合材料的弯曲强度、弯曲弹性模量、显微维氏硬度呈先升后降的趋势。当氧化锌晶须用量为5％时,以上指标测得值最高,分别为（109．00±2．70）MPa、（3645．30±198．68）MPa、（20．57±0．85）kg／mm^2,树脂基托较对照组弯曲强度提高18．29％、弯曲弹性模量提高16．07％、显微维氏硬度提高29．94％。结论：氧化锌晶须填料显著增强了基托树脂的力学性能。     

不同类型义齿清洁剂对着色热凝基托树脂和树脂人工牙的清洁效果

目的:比较不同类型义齿清洁剂对着色热凝基托树脂和树脂人工牙的清洁效果.方法:将40块规格相同的热凝基托树脂试件和40颗贺利氏树脂人工中切牙,浸泡于咖啡、绿茶和酱油的混合液中4周,各随机分为4组(n=10),按使用说明分别浸泡在Polident、Steradent清洁片配成的溶液、质量分数为0.5％次氯酸钠溶液和蒸馏水(对照组)中4h,使用色差仪和电子比色仪分别测量热凝基托树脂和树脂人工牙着色前后、清洁剂浸泡后的色度值,计算试件处理前后的色差(△E)并进行统计学分析.结果:在着色前后,4组热凝基托树脂和4组树脂人工牙△E无统计学差异(P＞0.05).在着色后与清洁后的△E值,0.5％次氯酸钠组＞ Polident组和Steradent组＞蒸馏水组(P＜0.05);Polident组与Steradent组之间无统计学差异(P＞0.05).在着色前与清洁后,蒸馏水组的△E大于其他3组(P＜0.05);其他3组之间无统计学差异.结论:0.5％次氯酸钠、Polident和Steradent对着色热凝基托树脂和树脂人工牙均有有效的清洁效果,其中0.5％次氯酸钠优于Polident和Steradent,Polident和Steradent效果相同.     

义齿基托树脂的力学性能研究

通过测试４种商品义齿基托树脂的弯曲强度，冲击强度，挠度及弹性模量，评价了采用可见光，热和微波聚合的基托树脂的力学性能，结果显示：热处理效果优于光和自凝处理，在热处理中，水热优于热压，热压优于微波加热。     

改进自凝义齿基托树脂机械性能的研究

目的 :本研究是在自凝塑料的液剂中加入一定量的高沸点丙烯酸酯 ,用统计方法对改变后的基托材料的力学数据进行分析处理 ,考察它们对固化后的材料力学性能的影响。方法 :在 6 4.0 0mm× 10 .0 0mm× 2 .5 0mm的模具中将四种材料各制备 15个试样 ,抛光后在 37℃的蒸馏水中恒温 2 4h备用。将制备好的试样于WD - 10A万能材料试验机上测试挠度和挠曲强度 ,加荷速度 0 .75mm/min。再在 6 0 .0 0mm× 5 .0 0mm× 4.0 0mm的模具中将四种材料各制备 15个试样 ,在JX - 4型金属冲击强度试验机上测试冲击强度。所有数据进行方差分析 (a =0 .0 5 )。结果 :在自凝牙托水中加入 5 %的二甲基丙烯酸三甘醇酯组 ,其冲击强度下降 ,挠曲强度不变 ,挠度下降 ;加入 5 %的甲基丙烯酸 - 2 -乙基己酯组 ,挠曲强度、冲击强度、挠度均增加 ;加入 2 .5 %的甲基丙烯酸 - 2 -乙基己和二甲基丙烯酸三甘醇酯组 ,其挠曲强度和冲击强度均增加 ,但挠度不变。结论 :在自凝牙托水中加入一定比例的二甲基丙烯酸三甘醇酯和甲基丙烯酸 - 2 -乙基己酯 ,能在一定程度上改善自凝义齿基托的性能     

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。     

Impact of ZrO2 nanoparticles addition on flexural properties of denture base resin with different thickness

PURPOSEThis study aimed to evaluate the effect of incorporating zirconium oxide nanoparticles (nano-ZrO₂) in polymethylmethacrylate (PMMA) denture base resin on flexural properties at different material thicknesses.MATERIALS AND METHODSHeat polymerized acrylic resin specimens (N = 120) were fabricated and divided into 4 groups according to denture base thickness (2.5 mm, 2.0 mm, 1.5 mm, 1.0 mm). Each group was subdivided into 3 subgroups (n = 10) according to nano-ZrO₂ concentration (0%, 2.5%, and 5%). Flexural strength and elastic modulus were evaluated using a three-point bending test. One-way ANOVA, Tukey''s post hoc, and two-way ANOVA were used for data analysis (α = .05). Scanning electron microscopy (SEM) was used for fracture surface analysis and nanoparticles distributions.RESULTSGroups with 0% nano-ZrO₂ showed no significant difference in the flexural strength as thickness decreased (P = .153). The addition of nano-zirconia significantly increased the flexural strength (P < .001). The highest value was with 5% nano-ZrO₂ and 2 mm-thickness (125.4 ± 18.3 MPa), followed by 5% nano-ZrO₂ and 1.5 mm-thickness (110.3 ± 8.5 MPa). Moreover, the effect of various concentration levels on elastic modulus was statistically significant for 2 mm thickness (P = .001), but the combined effect of thickness and concentration on elastic modulus was insignificant (P = .10).CONCLUSIONReinforcement of denture base material with nano-ZrO₂ significantly increased flexural strength and modulus of elasticity. Reducing material thickness did not decrease flexural strength when nano-ZrO₂ was incorporated. In clinical practice, when low thickness of denture base material is indicated, PMMA/nano-ZrO₂ could be used with minimum acceptable thickness of 1.5 mm.     

Elastic modulus and flexural strength comparisons of high-impact and traditional denture base acrylic resins

Background

Fractures of acrylic resin dentures are a common occurrence in clinical dentistry. The denture may be fractured accidentally when dropped or while in service in the mouth due to flexural fatigue.

Objectives

The aim of this study was to compare the elastic modulus and the flexural strength between two heat-cured acrylic resins used in denture bases: a high-impact resin (Lucitone 199) and a traditional resin (Rodex).

Materials and methods

Rectangular strips of Lucitone 199 and Rodex (10 samples each) were fabricated and stored in artificial saliva at 37 °C for 2 weeks. The specimens were subjected to a three-point flexural test. The data were statistically analysed with Student’s t-test (p ⩽ .05).

Results

The high-impact acrylic resin had a lower elastic modulus (p = .000) and higher flexural strength (p = .001) compared to the traditional acrylic resin.

Conclusion

Within the limitations of this study, it can be concluded that the high-impact acrylic resin is a suitable denture base material for patients with clinical fracture of the acrylic denture.     

不同热加工方式对义齿树脂材料物理性能的影响研究

目的研究不同热加工方式对聚甲基丙烯酸甲酯义齿物理性能的影响.方法采用3种不同热加工方式:常规水浴、低温12 h水浴和低温24 h水浴聚合法,制作50 mm×6 mm×4 mm的树脂试样,用Charpy冲击试验机测量其冲击强度;制作64 mm×10 mm×2.5 mm的树脂试样,用电子万能试验机测量其弯曲强度和弯曲模量.结果常规水浴组、低温12 h组和低温24 h组不同热加工方式制作试样的冲击强度、弯曲强度逐渐升高,弯曲模量逐渐降低.结论本实验中低温长时间聚合的义齿其物理性能最佳.     

3种“活动矫治器”基托材料热压处理前后性能比较

目的:比较咬合诱导"活动矫治器"3 种基托材料的弯曲强度、冲击强度、粗糙度、弹性模量和色度,为临床选择材料提供依据.方法:以日进齿科材料有限公司生产的自然义齿基托聚合物Ⅱ型(以下简称日进)、日本株式会社而至生产的而至快速自凝基托树脂(以下简称而至)、上海二医张江生物材料有限公司生产的义齿基托树脂液Ⅱ型和上海医疗器械股份有限公司齿科材料厂生产的义齿基托树脂Ⅱ型(以下简称混合) 3 种基托材料为研究对象,对基托材料进行热压处理;测试挠曲强度、冲击强度、粗糙度及测试色度.测试结果用SPSS 12.0软件进行方差分析和Tamhane T2检验.结果:同一材料的"加压处理组"和"未加压处理组"比较,所有材料冲击强度的改变均有统计学意义,除此以外,个别材料挠曲强度和色度的改变有统计学意义.对于不同材料同一性能的比较,冲击强度:而至＞"混合"＞日进;挠曲强度:日进＞"混合"＞而至;弹性模量:日进＞"混合"＞而至;粗糙度:而至>日进>"混合".结论:热压处理可以作为提高活动矫治器的基托性能的手段;3 种材料比较,各有长短.医师应该结合治疗实际情况选择最合适的材料.     

义齿清洁剂对热固化型基托树脂物理及机械性能的影响

目的 评价5种义齿清洁剂对热固化型基托树脂颜色稳定性、表面粗糙度、弯曲强度的影响。方法 热固化型基托树脂试样浸泡于保丽净、澳多—C、Protefix、0.2%葡萄糖酸氯己定、雅克菱义齿清洁剂以及蒸馏水中,后测量试样颜色的改变(ΔE)、粗糙度值、弯曲强度。结果 0.2%葡萄糖酸氯己定、雅克菱义齿清洁剂的颜色改变较对照组显著较大;将ΔE值用NBS（美国国家标准局）单位来表示,所有组对应的人色差感觉程度均为感觉轻微。对于表面粗糙度和弯曲强度,不同浸泡处理组间无统计学差异。结论 热固化型基托树脂使用义齿清洁剂180 d后,0.2%葡萄糖酸氯己定、雅克菱浸泡后颜色稳定性较差,但为临床可接受。保丽净、澳多—C、Protefix对材料均无影响。     

In vitro comparison of two different materials for the repair of urethan dimethacrylate denture bases

PURPOSE

The purpose of this in vitro study was to investigate the flexural properties of a recently introduced urethane dimethacrylate denture base material (Eclipse) after being repaired with two different materials.

MATERIALS AND METHODS

Two repair groups and a control group consisting of 10 specimens each were generated. The ES group was repaired with auto-polymerizing polymer. The EE group was repaired with the Eclipse. The E group was left intact as a control group. A 3-point bending test device which was set to travel at a crosshead speed of 5 mm/min was used. Specimens were loaded until fracture occurred and the mean displacement, maximum load, flexural modulus and flexural strength values and standard deviations were calculated for each group and the data were statistically analyzed. The results were assessed at a significance level of P<.05.

RESULTS

The mean "displacement", "maximum load before fracture", "flexural strength" and "flexural modulus" rates of Group E were statistically significant higher than those of Groups ES and EE, but no significant difference (P>.05) was found between the mean values of Group ES and EE. There was a statistically significant positive relation (P<.01) between the displacement and maximum load of Group ES (99.5%), Group EE (94.3%) and Group E (84.4%).

CONCLUSION

The more economic and commonly used self-curing acrylic resin can be recommended as an alternative repair material for Eclipse denture bases.     

注塑基托树脂力学性能的检测

目的：对Vertex注塑基托树脂的力学性能进行研究,为临床开展注塑技术提供理论依据。方法：分实验对照两组,实验组为注塑基托树脂,对照组为临床常用热凝基托树脂,按照2种基托树脂的操作步骤要求进行试样制备,对不同基托树脂的试样在材料试验机上测定其冲击强度、弯曲强度、弹性模量和布氏硬度,并对断面进行电子显微分析。结果：注塑基托树脂和热凝基托树脂的冲击强度分别为6.01±0.50KJ/mm^3,7.35±0.93KJ/mm^3,（P〉0.05）,弯曲强度为104.44±3.07MPa,90.19±6.88MPa,（P〈0.05）,弹性模量为2.1±0.2GPa,2.4±0.1Gpa,（P〉0.05）,布氏硬度为12.17±0.93kg/mm^2,19.57±2.89kg/mm^2,（P〈0.05）;两种基托树脂的微观结构有明显不同,注塑基托树脂内部分布着许多粒径颗粒。结论：Vertex注塑基托树脂不仅具有热凝基托树脂的抗冲击能力,还具有良好的抗弯性能,韧性佳,是一种比较好的义齿基托树脂。