不同种类的熔模材料对铸造冠蜡型边缘适合性的影响

目的:研究不同种类的熔模材料对铸造冠蜡型边缘适合性的影响。方法:制作模拟后牙全冠预备体外形的标准帽状试件及圆管,于试件上制作铸造冠熔模蜡型。共完成4组。其中前三组熔模蜡型各采用一种类型的嵌体蜡制作,每组10个蜡型。第4组熔模蜡型采用前面使用的三种嵌体蜡分别与两种颈缘蜡匹配制作,共完成60个蜡型。在体式显微镜下观察测量熔模蜡型的边缘浮出量。结果:前两组熔模蜡型的边缘浮出量无显著性差异(P>0.05)。与其后两组比较均有显著性差异(P<0.05)。第三组松风嵌体蜡制作的熔模蜡型与第四组熔模蜡型间无显著性差异(P>0.05)。结论:松风嵌体蜡优于其他两种类型的嵌体蜡。颈缘蜡对边缘适合性的改善效果良好,两种颈缘蜡与三种嵌体蜡匹配性好。     

铸模焙烧温度对Plat—Ⅱ型铸造陶瓷全冠适合性的影响

本实验用500℃,550℃,600℃,650℃四种铸模焙烧温度铸造Plat-Ⅱ型铸造陶瓷(PCC—Ⅱ型)全冠48个,每组12个,用磷酸锌粘固粉粘固于各自的代型上,测试各组冠,各个部位的粘固剂厚度,比较其适合性,探讨了PCC—Ⅱ型的最适铸模焙烧温度.结果表明:四种焙烧温度铸造的Plat-Ⅱ型铸造玻璃陶瓷全冠适合性有显著差异,600℃组边缘浮升量最小(x=37.35μm);同一组冠的颊舌向、近远中向边缘浮升量无显著差异;同一冠的龈缘和(牙合)面粘固剂厚度远大于轴壁.     

不同制作工艺对金属基底边缘适合性影响的实验分析

目的：比较CAD／CAM制作的蜡熔模和树脂熔模与传统滴蜡法制作的蜡熔模对金属基底边缘适合性影响的差异。方法：采用标准模具制作标准代型18个,随机分为A、B、C三组,每组6个,A组代型滴蜡法制作蜡熔模,B组代型CAD／CAM制作蜡熔模,C组代型CAD／CAM制作树脂熔模。每一代型及熔模进行四点标记,分别进行包埋铸造,按标记点就位,对每一个代型就位后的金属基底用Leica显微镜在四个标志点对垂直边缘缝隙进行拍照,用Image-ProPlus6．0进行测量后,使用SAS9．13对结果进行方差分析及t检验。结果：A组：68．20±24．30μm;B组：46．31±23．43μm;C组：60．58±21．87μm。所有试件的垂直边缘缝隙均在120μm以内。经方差分析及t检验,三组之间（P=0．0061）差异有统计学意义,A、C两组（P=0．2600）之间差异无统计学意义,A组与B组（P=0．0027）、B组与C组（P=0．0343）之间差异均有统计学意义。结论：CAD／CAM制作的蜡熔模与CAD／CAM制作的树脂熔模、传统滴蜡法制作的蜡熔模相比,经铸造后的试件具有较好的边缘适合性。CAD／CAM与传统铸造法结合能获得边缘适合性良好的修复体。     

熔模类型及放置时间对冠熔模精度影响的研究

目的:研究3种不同熔模材料的蜡型及放置时间对冠熔模精密性的影响。方法:用同一标准模具翻制30个石膏代型,随机分为3组,每组10个,分别用日本松风公司、德国BEGO公司和国产的嵌体蜡在石膏代型上采用滴蜡法各制作10个熔模,于蜡型完成0、10、20、30、60、120、240min后,用投影测量仪测量蜡型边缘的浮出量,比较其边缘的密合性。结果:3种材料的冠蜡型在前20min的边缘浮出量与20min后的边缘浮出量有高度差异性(P<0.01),30min的边缘浮出量与60、120、240min的浮出量无差异性(P>0.05);在各个时间点,松风蜡及BEGO蜡的边缘浮出量和国产蜡的边缘浮出量有高度差异性(P<0.01),在0、10和20min,松风蜡与BEGO蜡间有差异性(P<0.05)。结论:不同种类的熔模材对冠蜡型的精度影响不同,在本试验中,松风蜡冠熔模的密合性较好;熔模完成后在0min时精度最高,30min后对精度的影响较小。     

压接技术对蜡熔模边缘适合性影响的实验研究

目的探讨压接作用在蜡熔模制作时对蜡熔模边缘适合性的影响。方法制作模拟后牙全冠外形的标准代型及圆管,然后分别采用压接法（实验组）和滴蜡法（对照组）各制作12个蜡熔模,测量蜡熔模制作完成尚未脱离代型、脱离代型0.5 h、脱离代型24 h后蜡熔模与代型的垂直边缘缝隙和水平边缘缝隙,计算完全边缘缝隙。结果蜡熔模在制作完成尚未脱离代型时,实验组与对照组的完全边缘缝隙之间有统计学差异（P<0.05）。放置0.5 h与放置24 h相比较,实验组、对照组蜡熔模的完全边缘缝隙均有统计学差异（P<0.01）。结论压接技术可提高蜡熔模的边缘适合性,蜡熔模的放置时间会影响蜡熔模的边缘适合性。     

3D打印多单位固定桥蜡型熔模基底冠适合性研究

［摘要］目的 分析与探讨3D打印制作多单位固定桥基底冠熔模蜡型的适合性。方法 统一制作相同前牙6个单位固定桥模型50个, 随机分成两组,其中实验组25个,对照组25个。实验组用3D打印制作基底冠树脂蜡型,对照组用传统手工浸蜡方式制作基底冠蜡型。采用扫描电镜比较基底冠与模型的密合性,每个模型取4点,分别为固定桥两端基牙的唇侧、舌侧边缘,同时对两组金属基底冠就位与外形修整技师所耗时间进行比较。 结果 3D打印制作的多单位前牙固定桥其基底冠的稳定性、适合性均优于传统手工浸蜡法,并可以显著缩短技师操作时间。 结论 3D打印制作固定桥熔模蜡型具有良好的适合性和稳定性,值得在口腔修复工艺中应用与推广。     

纯钛基桩与其镍铬合金全冠的粘接固位力研究

目的　旨在探讨现有的三种常用水门汀在纯钛种植体基桩上的全冠固位力差异。方法　通过精密机床技术加工凹形龈缘种植体基桩的纯钛代型 10个 ,按全冠要求制作熔模 ,常规包埋后用烤瓷合金 (镍铬合金 )铸造。用自凝塑料包裹全冠 ,通过万能实验机测量记录分别用氧化锌丁香酚、磷酸锌、玻璃离子水门汀粘接后的全冠固位力大小。结果　氧化锌丁香酚、磷酸锌、玻璃离子水门汀粘接的冠固位力分别为 6 1.5 0± 7.40N、2 81.35±2 3 .2 2N、2 46 .95± 2 0 .10N。结论　在纯钛基桩上 ,氧化锌丁香酚水门汀提供的冠固位力要远小于永久性粘固剂 ,磷酸锌水门汀表现出的冠固位力显著高于玻璃离子     

不同种类的熔模材料对铸造冠边缘适合性影响的实验研究

目的 :观察磷酸盐包埋材料内部膨胀受不同种类熔模材料软化温度的作用和对铸造冠边缘适合性的影响。方法 :制作模拟后牙全冠外形的标准帽状试件及圆管 ,于试件上制作 3 0个熔模 ,并随机分为 3组 ,每组 10个熔模。每组分别采用不同的熔模材料制作熔模。第 1组采用软质嵌体蜡制作 ,第 2组采用硬质嵌体蜡制作 ,第3组采用自凝复合树脂制作 ,3组均按照Dentaurum包埋材料的使用说明进行有圈包埋 ,采用与Dentaurum包埋材料配套的DentaurumNiCrMo合金进行铸造。铸造冠在原标准帽状试件上试合 ,在扫描电镜下测量铸件的边缘浮出量。结果 :前 2组间的边缘浮出量无显著性差异 (P >0 .0 5 )。第 3组与前 2组间的边缘浮出量有显著性差异(P <0 .0 5 )。结论 :不同熔模材料的软化温度对铸造冠边缘适合性有影响。熔模材料软化温度越高 ,铸造冠边缘浮出量越明显。     

《口腔颌面修复学杂志》第6卷关键词索引

(按汉语拼音字母顺序排列)BBennett角A R C U S digm a下颌运动轨迹记录仪获取牙合架参数精确度的研究(李鸿波冯海兰)(2):86白色念珠菌配戴可摘义齿对口腔白色念珠菌的检出及基因分型的影响(颜世果戚向敏林荔梅等)(4):280比色板In-C eram渗透陶瓷技工比色板的色度学研究(伊元夫温宁王忠义等)(1):16边缘1180颗金属烤瓷冠与牙龈健康关系调查(李荣宋宏杰王凌成等)(2):93边缘浮出量不同种类的熔模材料对铸造冠蜡型边缘适合性的影响(侯晓冲王忠义王宝成)(1):30边缘适合性不同种类的熔模材料对铸造冠蜡型边缘适合性的影响(侯晓冲王忠义王宝成)…     

影响瓷甲冠适合性的因素

甲冠适合性一般认为是存在于预备牙与修复体组织面间的间隙,大的边缘间隙,菌斑在近龈缘处聚积而增加了继发龋和牙周病的产生,同时边缘完整性的丧失,不同区域适合性的差异可引起应力集中,而降低修复体的强度。材料与方法 60个上颌切牙与尖牙,30个制备成1 mm的方型台肩,30个制备成深凹面。用 Vita 铂型芯陶瓷,Vitadur-N 牙本质和牙釉质瓷制作全冠。烧结后,去除两组中半数冠的箔片。用三种粘固剂(磷酸锌粘固剂,玻璃离子粘固剂,复合树脂粘固剂)分别粘周5个未去除箔片的冠和5个去除箔片的冠到两组预     

Evidence of the validity of a model of determinants of quality of restorative dental care

A model describing the relationship between self-reported quality of restorative dentistry and dentist characteristics for 119 Montana general dentists is presented. The best predictors formed a significant model explaining 22% of the variance of the quality measure. Results are contrasted with a previous estimation of the model for 102 Washington general practitioners. Evidence for the external validity of the model is presented.     

不同剂型玻璃离子水门汀溶解性比较研究

目的:研究、比较不同剂型玻璃离子水门汀的溶解性和表面微观形态改变,为临床使用提供依据.方法:将3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)及GC玻璃离子水门汀(双糊剂型)分别在人工唾液中浸泡30 d,冷热循环15000次,烘干测重,比较前后质量变化,计算溶解率,并用扫描电镜观察表面微观改变.结果:不同剂型的玻璃离子水门汀溶解率由高到低分别为3M树脂加强型玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(水粉剂型)、GC玻璃离子水门汀(双糊剂型).3种玻璃离子水门汀经浸泡溶解后,SEM扫描表面微观形态可观察到GE玻璃离子水门汀(双糊剂型)表面形态改变较少,其他2组玻璃离子水门汀表面微观改变较多.结论:双糊剂型玻璃离子水门汀理化性能及溶解率均低于传统水粉剂型,是未来临床修复治疗的的良好选择.     

Evaluation of efficacy of chemiluminescence for diagnosis of leukoplakia

ObjectiveLeukoplakia is the most common potentially malignant disorder preceding oral cancer. Chemiluminescence has been developed as an adjunct to conventional examination for the diagnosis of these potentially malignant disorders. This study was conducted to assess the efficacy of chemiluminescence in the diagnosis of leukoplakia and to compare the results with histopathological examination.Study designA total of 50 patients with leukoplakia were included from the outpatients attending the Department of Oral Medicine and Radiology, Dental Hospital, Bengaluru, Karnataka, India. These patients were subjected to conventional oral examination followed by chemiluminescent examination with Vizilite (Zila, Fort Collins, CO, USA) and biopsy for histopathological confirmation.ResultsThe sensitivity, specificity, positive predictive value, and negative predictive value of chemiluminescence were 93.75%, 55.56%, 78.95%, and 83.3%, respectively. The overall accuracy of chemiluminescence was 80%. A statistically significant association was observed between histopathology results and chemiluminescence results.ConclusionAlthough it is an easy, safe, minimal time consuming, and noninvasive technique, it has only adjunctive utility and it does not replace biopsy for the diagnosis of leukoplakia.     

正畸患者切牙影像失真发生情况分析

目的研究正畸患者曲面体层片上的切牙影像失真发生情况，并分析其原因。 方法从中山大学附属口腔医院放射科影像数据库中选取500例正畸患者的曲面体层片和头影测量侧位片，所有曲面体层片均采用咬合杆投照，分别从切牙牙体影像放大、缩小、牙根变短、根尖模糊等评价指标分析上下颌切牙影像失真的发生情况，在头影测量侧位片上测量中切牙根尖-对颌切牙切缘的距离，探讨切牙影像失真发生的原因。采用SPSS 19.0统计软件对所得数据进行统计学检验。 结果500例患者中，切牙牙体影像正常者共417例，切牙牙体影像失真者共83例，影像失真发生率16.6%，其中切牙牙体影像放大17例、牙体影像缩小0例、牙根变短30例，牙根影像变短伴模糊36例。影像失真患者的根尖-切缘距离大于影像正常的患者，差异有统计学意义（F = 5 187.18，P = 0）；影像失真患者的覆盖值大于影像正常的患者，差异有统计学意义（F>477，P = 0）。 结论严重牙颌面畸形如反 、深覆盖是导致曲面体层片的切牙影像失真的主要原因之一。     

Design of clinical trials of traditional therapies of periodontitis

The present paper on the design of clinical trials of periodontal therapy first addresses the issue of the etiology of periodontal disease. It is suggested that most if not all forms of destructive periodontal disease are caused by microorganisms and that there are different forms of disease with different microbial etiologies. The progressive nature of destructive periodontal disease is subsequently discussed and it is emphasized that, in a given patient, periodontal sites which show signs of inflammation and attachment loss may not over a period of several months and years show further sign of attachment loss. The present methods of assessing periodontal disease do not allow us to discriminate between potentially active and inactive sites in untreated patients. The significance and variability of indicators of periodontal disease such as bleeding on probing, probing pocket depth and probing attachment level measurements are discussed. The errors inherent in the various measurements are analyzed and suggestions are presented describing how alterations in any of the above parameters could be identified and presented in a clinical trial. Of concern for the statistical analysis of clinical data of periodontal disease is the definition of the "experimental unit". For a number of years, the "experimental unit" in periodontal trials was the patient. It is clear, however, that different sites within the same individual show different patterns of disease progression and lesion morphology and often respond differently to periodontal therapy. Statistical analyses must consequently be designed which recognize differences in site-to-site infection and lesion morphology within a common host. Until such analyses are available, the investigator should be wary of pooling data within the same individual, since such pooling may obscure meaningful alternatives which may take place in individual periodontal sites. Some goals of periodontal therapy are subsequently identified. 4 goals are discussed more in detail, namely: to establish conditions which will allow the patient to maintain a dentition without further breakdown of the periodontium; to reduce pocket depth to establish an anatomy in the dentogingival region which with proper maintainance care will prevent the re-establishment of the subgingival infection; to gain attachment as a result of treatment; to assess the effect of a certain chemotherapeutic agent on periodontal disease.     

Experimental evidence of formation of imines in the course of reduction of hydrazones

The reduction of hydrazones is generally suggested to proceed through a reductive cleavage of the nitrogen–nitrogen bond followed by a reduction of the carbon–nitrogen bond. This sequence of reduction processes is here supported for fluorenone (V) and benzophenone (VI) hydrazones as well as by a comparison of the reduction of fluorenone and benzophenone hydrazonium ions (I,III) with corresponding imines (II,IV). Another proof of the presence of imines as intermediates is the splitting of four-electron waves of hydrazones V and VI and hydrazonium ions I and VIII into two waves at pH < 2. This has been interpreted as due to differences in slopes dE_1/2/dpH and pK_a-values of protonated hydrazine derivatives on one side and corresponding imines on the other. In this pH-range imines formed in reductions of VI and VIII are reduced in a single two-electron wave, those of I and V in two one-electron steps. Fluorenone imine (II) is sufficiently stable to allow recording of time-independent current–voltage curves between pH 6 and 11. In this pH-range the imine (II) is reduced in two one-electron steps. Benzophenone imine (IV) has been found stable between pH 4.6 and 12. At pH 4.6–8 the reduction of the imine IV takes place in a single two-electron step, at pH 8–12 in two one-electron steps. Final proof of the initial cleavage of the N–N bond is presented by comparison with the reduction of nitrones.     

比色板标准与非标准色标识别差异的初探

目的 测试口腔修复学专业研究生对比色板标准色标与非标准色标颜色识别的差异,评价、分析口腔修复学专业研究生临床实际比色能力,为探讨临床比色教学方法提供客观的基础数据.方法 选择具有1～5年临床工作经验、排除色觉识别障碍、经过色彩学知识培训的口腔修复学专业研究生62名.从比色板A(Lineargnide)的29个标准色标中通过随机数字表抽取7个色标作为标准色标,以比色板B(Vita Bleachadgnide 3D-Master)中的7个色标作为非标准色标,在D55标准光源下,以比色板C(Vita 3D-Master)作为比色工具,对标准色标和非标准色标进行比色测试.计算受试者对两种色标比色的总体准确率;统计比色正确的人数分布,并进行Monte Carlo确切概率法检验;统计比色结果在明度、饱和度、色相上的等级偏差,并进行Wilcoxin符号秩和检验.结果 受试者对标准色标比色的总体正确率为45.9%(199/434),对非标准色标比色的总体正确率为9.0%(39/434);对两种色标比色正确的人数分布的差异有统计学意义(P<0.001);对两种色标比色结果的明度等级偏差[分别为0.2(0.1～0.3)、0.4(0.4～0.5)]、饱和度等级偏差[分别为0.2(0.1～0.4)、0.5(0.4～0.6)]的差异均有统计学意义(P<0.01),色相等级偏差[分别为0.3(0.1～0.4)、0.3(0.1～0.4)]的差异无统计学意义(P=0.079>0.01).结论 口腔修复学专业研究生对比色板非标准色标颜色的识别能力明显低于对标准色标颜色的识别能力.     

正常青年Monson球面半径的测量研究

目的测量正常青年Monson球面半径。方法选择60名(男30名,女30名)正常青年制取全口印模,应用立体摄影成像的原理与方法对Monson球面半径进行测量和统计学处理。结果Monson球面的半径平均为10.173 cm,大于理论值10.160 cm,差异有显著性(P<0.01);男、女性球面半径差异无显著性。结论本实验所得到的数据可作为全口义齿修复中记录颌位关系的一个参量。     

连续波热牙胶充填技术根尖封闭性能的评估

目的体外实验比较不同器械预备根管后连续波热牙胶根管充填技术的根尖封闭能力。方法离体双根管上颌前磨牙随机分为机用ProFile预备组和不锈钢K锉预备组,分别采用连续波热牙胶充填技术和冷侧压法进行根管充填,用染料渗透法和透明标本法测量根尖微渗漏,评价各组根尖封闭能力。结果各组根尖微渗漏距离无统计学差异(P>0.05)。结论连续波热牙胶充填技术与冷牙胶侧方加压充填技术的根尖封闭能力无显著性差异;对直根管和轻度弯曲的根管,不同器械根管预备后其根管充填效果无明显影响。