浸泡消毒对海藻酸盐印模三维尺寸稳定性影响的评价

目的评价海藻酸盐印模分别接受2%酸性戊二醛、2%碱性戊二醛、2%强化中性戊二醛、84消毒液(有效氯含量为0.3%)的30分钟浸泡消毒处理后的三维尺寸稳定性的变化。方法采用同一个标准模型制取印模。实验分为四个消毒处理组,不处理组作为对照组。采用三维坐标扫描机分析消毒处理后的印模灌制出模型的尺寸改变,精确度可达0.001mm。结果除了2%强化酸性戊二醛处理组各项指标均与对照组没有显著性差异以外(P>0.05),其余三个消毒处理组均在水平向、垂直向和角度等方面与对照组出现显著性差异(P<0.05)。结论2%酸性戊二醛浸泡消毒30分钟,对海藻酸盐印模的三维尺寸稳定性没有显著性影响。     

浸泡消毒对藻酸盐印模模型精度的影响

目的 了解戊二醛和二氧化氯对两种印模浸泡消毒后对模型精度的影响。方法 用标准试件制取贺利氏和红叶藻酸盐印模。每种材料取7组，1组用清水冲洗作为对照，其余各组分别用2％戊二醛和7．35mol／L（500ppm）二氧化氯浸泡10、20、30min后用超硬石膏灌模，静置24h后用电子数显游标卡尺测量模型并行统计分析。结果 两种印模在2％戊二醛中浸泡，除贺利氏浸泡10min外，其它各组较对照组均有形变（P〈0．05）；7．35mol／L二氧化氯浸泡，各组较对照组均无明显形变（P〉0．05）。结论 7．35mol／L二氧化氯对藻酸盐印模形变的影响比2％戊二醛小；用2％戊二醛和7．35mol／L二氧化氯浸泡消毒贺利氏和红叶两种藻酸盐印模，10min内不影响印模的精度。     

浸泡消毒对硅橡胶印模三维尺寸稳定性的影响

1 材料与方法:①标准模型:制作一个模拟牙弓的不锈钢标准模型,其上放置 4个轴面聚合度均为 6°的锥柱状代型A、B、C、D。用自凝聚丙烯酸甲酯制作配套的个别托盘。②消毒制剂: 2 % 酸性戊二醛和 2 % 碱性戊二醛 (鑫四环消毒技术开发中心); 2 % 强化中性戊二醛 (利康消毒高科技有限公司); 84消毒液(柯林龙安医学技术有限公司,实验中有效氯含量为 0 3 % )。③样本制备:测试用缩合型硅橡胶印模材(ColtèneSpeedex,瑞士ColtneAG公司 )。采用二次印膜法制取印膜。处理组浸泡时间均为 30min(中华人民共和国卫生部.消毒技术规范. 2002. 162 …     

玉洁新消毒液调拌藻酸盐印模材临床效果评价

目的:应用玉洁新消毒液调和藻酸盐印模材料拓取牙颌模型后,评价印模表面细菌含量及模型尺寸精度的变化。方法:取印模前用无菌棉拭子在志愿者前牙舌侧窝采样,而后用玉洁新消毒液漱口,3min后应用玉洁新消毒液调和藻酸盐印模材料取模,于印模所对应的前牙舌侧窝处取样,4h内送检,接种于营养琼脂平皿,37℃培养48h,进行细菌定性分析。再以同一金属模型为母模,应用玉洁新消毒液调和藻酸盐印模材料制取10个印模,以超硬石膏灌模,比较石膏模型与母模之间指标线段长度差异。结果:(1)消毒前有细菌存在,消毒后印模细菌阴性培养率为100%。(2)经测量灌制的石膏模型与母模之间指标线段长度形变率为0.15%-0.18%。结论:结果显示从统计学和临床的观测,应用玉洁新消毒剂自体消毒印模所合成的石膏模型并不引起显著的尺寸改变。     

浸泡消毒藻酸钾印模对模型尺寸稳定性的影响

目的使用不同消毒剂浸泡消毒口腔印模，观察其对模型尺寸稳定性的影响。方法制取塑料母模印模试件60件，按消毒剂不同随机分为3组，每组18个试件，分别浸没于2％强化中性戊二醛，0．5％次氯酸，0．1％碘伏中。每组再按消毒时间不同分3组，每组6个试件，分别浸泡10min、20min、30min后取出灌注模型。对照组6个试件直接灌注模型。24h后测量显微镜测量各组石膏模型6近远中径（MD），6颊舌径（LB），6｜6间距（CA），36间距（AP）线性长度值。SPSS10．0做统计学处理，统计藻酸钾印模浸泡前后模型尺寸有无显著改变及改变量。结果①使用析因设计两因素方差分析对模型测量值MD，LB，AP，CA进行分析。结果显示处理组P值均小于0．05，区组因素P值均大于0．05。②使用Dunnett-T检验把浸泡各时间组模型尺寸与浸泡前比较，结果显示浸泡10min模型线性长度与对照组均无显著性差别，浸泡20min，30min组各测量值与对照组相比均有显著性差异。结论①浸泡消毒藻酸钾印模，消毒剂种类不影响模型尺寸稳定性。消毒时间可影响模型尺寸稳定性。②随浸泡消毒时间延长，模型尺寸改变增大，浸泡30min内尺寸改变在临床允许范围内。     

浸泡消毒对硅橡胶印模三维尺寸稳定性的影响

目的：评价缩合型硅橡胶印模分别接受2%酸性戊二醛、2%碱性戊二醛、2%强化中性戊二醛、84消毒液（有效氯含量为0.3%）的30min浸泡消毒处理后的三维尺寸稳定性的变化。方法：用同一个标准模型制取印模,采用三维坐标扫描机分析消毒处理后的印模灌制出模型的尺寸改变,精确度达0.001mm。不处理组作为对照组。结果：只有84消毒液处理组的印模形变超出石膏及印模自身凝固形变可以解释的范围,其余3个消毒处理组的模型虽然在水平向、垂直向和角度等方面与对照组的差异具有显著性（P〈0.05）,但最终形变量仍可以为临床所接受。结论：2%戊二醛（不同酸碱性）浸泡消毒30min,对缩合型硅橡胶的三维尺寸稳定性没有显著影响。     

两种消毒液调拌藻酸盐印模材对印模尺寸稳定性的影响

目的：评价用两种消毒液直接调拌藻酸盐印模材对印模尺寸稳定性有无影响。方法：分别用蒸馏水、0．2％的次氯酸钠和0．1％的洗必泰调拌藻酸盐印模材,对同一试件制取20组印模,以蒸馏水调拌者为对照组。用超硬石膏灌模,40rain脱模静置24h测量模型三维标志点的长度再进行统计学分析。结果：试验组和对照组模型三维标志点长度无显著性差异。结论：0．2％的次氯酸钠或0．1％的洗必泰直接调拌藻酸盐印模材进行印模消毒不影响印模尺寸稳定性,可用于口腔科印模消毒。     

2％酸性戊二醛对藻酸盐印模浸泡消毒的效果评价

目的评价2％酸性戊二醛浸泡消毒对藻酸盐印模表面的变形链球菌“C”、白色念珠菌、大肠杆菌、金黄色葡萄球菌和枯草杆菌黑色变种芽孢的消毒效果。方法制作5cm×5cm大小无菌印模试件,分成5组,分别用变形链球菌“C”、白色念珠菌、大肠杆菌、金黄色葡萄球菌和枯草杆菌黑色变种芽孢5种菌液污染。采用2％酸性戊二醛对染菌印模进行浸泡消毒处理,以蒸馏水浸泡作为对照组。其后不同时间在印模试件表面取样、接种、培养,并进行CFU计数,计算抑菌率。根据抑菌率大小评价消毒效果。结果2％酸性戊二醛浸泡消毒10min,可对藻酸盐印模表面的变形链球菌“C”、白色念珠菌、大肠杆菌和金黄色葡萄球菌达到有效消毒,在实验限定的作用时间内对枯草杆菌黑色变种芽孢消毒无效。结论2％酸性戊二醛浸泡为有效的印模消毒方法,但不能达到高水平的消毒。     

新洁尔灭调拌消毒法对藻酸盐印模材料尺寸稳定性的影响

目的：研究藻酸盐印模材料与4种不同浓度新洁尔灭消毒液调拌对印模尺寸稳定性的影响。方法：用0.05%、0.10%、0.15%、0.20%新洁尔灭消毒液调拌藻酸盐印模材作实验样本,以蒸馏水调拌相同材料制取印模做对照,分别制取15组试件印模。用超硬石膏灌模,60min后脱模,石膏模型静置2h后,用高精度数显游标卡尺测量石膏模型,进行统计学分析。结果：实验组模型与对照组模型尺寸稳定性无显著性变化,4组实验组间比较,亦无统计学上的显著性差异。结论：0.05%、0.10%、0.15%、0.20%新洁尔灭消毒液调拌藻酸盐印模材不影响印模精度,0.20%新洁尔灭可作为临床上印模常规消毒方法。     

几种有效消毒方法对藻酸盐印模精度的影响

目的：比较几种有效的消毒方法对藻酸盐印模精度的影响，以寻求适合临床的消毒方法。方法：制作一个标准下颌牙列金属母模。采用3种有效的消毒方法（1500mg／L的NaClO消毒液浸泡消毒，1500mg／L的NaClO消毒液喷涂消毒及2％戊二醛消毒液浸泡消毒），分别按起效作用时间、起效作用时间延长10min和延长20min共分为9个实验组，每组均制备10个藻酸盐印模进行消毒处理后灌制模型，另外制取10个未消毒的藻酸盐印模作为对照组，用测量显微镜测量模型各标志点的距离，所得数据进行统计分析。结果：①1500mg／L的NaClO消毒液浸泡消毒10～30min对印模精度无明显影响。②1500mg／L的NaClO消毒液喷涂消毒藻酸盐印模45min时，出现统计意义显著的形变（P〈0．05）。③2％戊二醛消毒液浸泡处理50min、60min时，印模出现统计学意义显著的形变（P〈0．05）。结论：不影响藻酸盐印模精度的消毒方法为：1500mg／L的NaClO消毒液浸泡消毒10～30min，1500mg／L的NaClO消毒液喷涂消毒25～35min，2％戊二醛消毒液浸泡处理40min。     

The dimensional stability of impression materials and its effect on in vitro tooth wear studies

Objectives

To assess the dimensional stability of 8 impression materials over 12 weeks relevant to in vitro tribology studies.

Methods

Ten impressions from eight impression materials were taken of a metal block (ADA block) conforming to the American Dental Association specification for impression materials and of another metal block (custom block) which allowed measurements over a larger surface area. The impressions and blocks were scanned on a non-contacting laser profilometer (Taicaan^® - Southampton, UK) and using surface metrology software Boddies^® (Taicaan^® - Southampton, UK) measurements were made at 24 h, 2, 4, 8 and 12 weeks. The impression materials tested were [1] Aquasil^®, [2] Aquasil^® DECA, [3] Affinis^®, [4] Express^®, [5] Extrude^®, [6] Impregum^®, [7] President^® and [8] Take 1^®.

Results

Seven addition silicones and one polyether [6] were tested. [2] and [6] were monophasic, the rest were putty-wash. The results from impressions of the ADA block showed that all materials contracted compared to measurements obtained directly from the block [1] expanded over time (+31.5 μm) (p < 0.05). The results from the custom block showed that all materials contracted compared to direct measurements of the block. [4] and [7] expanded over time (+62 μm and +63.8 μm respectively). [8] contracted over time (−54.7 μm) (p < 0.05).

Significance

No material showed linear changes >1.5% and were stable for 12 weeks. Nevertheless, the range of changes would affect tribology studies were cut-offs lesser than the reported changes are selected. All impressions should be processed after similar time delays to reduce the errors introduced by dimensional changes.     

藻酸盐印模材料水粉比及印模放置时间对模型精度的影响

目的 :观察水粉比及印模放置时间对藻酸盐印模材制取全牙列模型精度的影响。方法 :制取一个标准下颌牙列金属母模。用 3种水粉比 ( 2 3∶10 ;30∶10 ;33∶10 )调拌藻酸盐印模材料 ,制取 30个模型 ,每组 10个。再用两种水粉比 ( 2 3∶10 ;30∶10 )各制取 30个印模 ,分别放置不同时间 ( 0、15、30min)灌制模型。用测量显微镜测量模型各标志点的距离 ,所得数据进行统计分析。结果 :①不同的水粉比制备印模 ,当水粉比为 33∶10时 ,66间线段长度的标准差异常增大 (s =0 .2 0 6) ,其余线段的长度变化无明显统计学意义 (P >0 .0 5 ) ;②随着放置时间的延长 ,印模出现收缩变形 ,统计有显著差异 (P <0 .0 1)。结论 :①适量增加水粉比 ,模型仍可获得较高的精度 ,但随着水粉比的增加 ,印模强度下降 ,容易变形 ;②随着放置时间的增加 ,印模收缩变形     

口腔印模消毒处理对模型精度的影响

目的:比较藻酸钾印模、琼脂藻酸钾联合印模和Express Putty硅橡胶印模分别用2％戊二醛、1％84消毒液不同方式、不同时间处理后对模型精度的影响。方法:用20mm×20mm×40mm标准试件制取藻酸钾、琼脂和硅橡胶印模。每种材料取45个,分9组,每组5个;一组用清水冲洗作对照组,其余各组分别用2％戊二醛、1％84消毒液喷涂后静止10min或浸泡10min、20min、30min后用超硬石膏灌模,静止2h后用螺旋测位仪测量模型。实验结果用SPSS 11.0统计软件包进行统计分析。结果:清水冲洗立即灌模与喷涂消毒处理相比,无显著性差异(P>0.05,);藻酸钾和琼脂印模材料浸泡前与浸泡后各时段相比,均有显著差异,且随着时间的增加,产生统计学显著意义的尺寸变化(P<0.01):Express Putty硅橡胶印模材料浸泡前与浸泡后各时段无显著性差异(P>0.05);2％戊二醛浸泡消毒对各种印模材料精度的影响与1％84消毒液相比,无显著性差异(P>0.05)。结论:2％戊二醛、1％84消毒液浸泡消毒藻酸钾印模、琼脂藻酸钾联合印模和Express Putty硅橡胶印模,在20min内不影响修复体制作的精度,可试用于临床。     

消毒剂对印模材料尺寸稳定性的影响

目的　比较质量分数为 2 %戊二醛溶液与新型有机氯消毒剂———爱尔施消毒液浸泡两种藻酸盐和两种硅橡胶印模材料后 ,对材料尺寸稳定性的影响。方法　用 6 0mm× 10mm× 10mm金属试件制取印模 ,分别在质量分数为 2 %戊二醛溶液与爱尔施消毒液中浸泡 10、2 0、30min ,用JXD - 2 5 0B型数显读数显微镜测量浸泡前和浸泡后各时段印模材料的线性长度。每种印模材料分成 2组 ,每组 10个 ,用SPSS 10 .0统计软件包对结果作统计学分析。结果　爱尔施消毒液对各种印模材料尺寸稳定性的影响与质量分数为 2 %戊二醛溶液相比无显著性差异(P >0 .0 5 ) ;ImpregumF硅橡胶和ExpressPutty硅橡胶印模材料浸泡后的体积变化小于红叶和Cavex藻酸盐印模材料。结论　爱尔施消毒液不会影响印模材料的尺寸稳定性 ,可试用于临床印模的浸泡消毒 ;硅橡胶印模材料的尺寸稳定性优于藻酸盐印模材料     

3D cone-beam C.T. imaging used to determine the effect of disinfection protocols on the dimensional stability of full arch impressions

AimThis study aimed to investigate the dimensional stability of irreversible hydrocolloid and polyvinylsiloxane (P.V.S.) impressions after exposure to four commercial disinfectants using cone-beam computed tomography (CBCT).Materials and MethodsTwo different impression materials were tested: irreversible hydrocolloid and P.V.S. Four disinfection solutions were applied: BirexSE, Opti-Cide3, COEfect MinuteSpray, and CaviCide Spray. Distilled water was used as a control group. Each solution remained in contact with the impression for 5 min. Additional contact time of 5 min compromises time for scanning. The materials were evaluated for dimensional stability after the impression of a maxillary complete edentulous template via CBCT before and after being in contact with the disinfectant agents. Measurements were assessed on the digital models from A-B, B-C, and C-A points. Paired analyses (Wilcoxon Signed Rank test or paired Student's t-test) were used to analyze each measurement before and after the contact with the disinfectant agents. The variance for each measurement was also analyzed via a one-way analysis of variance or Kruskal-Wallis.ResultsOverall, there were no statistical differences among the points measurements in the irreversible hydrocolloid or P.V.S. between initial and final assessments (p > 0.05). The used disinfectant agents in this study did not influence each measurement's variation on irreversible hydrocolloid or P.V.S. (p > 0.05). All agents showed an effect on the dimensional stability of both impression materials. The differences in the three dimensions ranged between 0.34 and 1.54%.ConclusionWithin 10 min of removing the impression from the master cast, is study's findings indicated that the four commercially available disinfectants did not influence the dimensional stability of irreversible hydrocolloid or P.V.S. Further studies should be performed to elucidate the antimicrobial effect of these solutions applied as a spray on the surface of irreversible hydrocolloid and P.V.S. impressions.     

Influence of border moulding on the dimensional stability of complete denture impression trays

In the process of making a final impression for complete dentures, the dimensional stability of the impression tray is an important factor. The aim of this study was to measure the dimensional stability of trays of different materials, namely shellac (SH), clear thermoplastic acrylic (TP) and self-curing acrylic (SC), during the process of border moulding. Changes were measured in upper and lower trays immediately after manufacture, following storage for 24 h, directly following border moulding and 1, 2 and 14 days after moulding.

The trays were manufactured on a metal master model on which nine reference points for the upper tray and eight for the lower were measured by means of a measuring microscope. The dimensional changes relative to the master model were calculated. Self-curing acrylic and thermoplastic trays proved to be stable during the process of border moulding. The lower impression trays of shellac suffered appreciable shrinkage and were considered unreliable.     

The dimensional stability of self-disinfecting alginate impressions compared to various immersion regimes

Alginate impressions of a master acrylic study model pair were made in order to assess the effect of various disinfection techniques on dimensional stability. Impressions were made using self-disinfecting alginate, traditional alginate which had been dipped or soaked in a disinfecting solution, and included was a control group which was not disinfected. Inter- and intra-arch linear measurements of the resultant study casts were made using a Reflex Metrograph. The small differences found for the variables measured were not statistically significant.