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11.
Neslihan Eminkahyagil DDS MSc PhD ; Selim Erkut DDS PhD 《Journal of prosthodontics》2006,15(5):316-320
Immediate chairside replacement of an extracted anterior tooth may contribute to a patient's comfort, treatment acceptance, and expectations of treatment; however, fabrication of a custom restoration in the anterior region of the mouth may result in an esthetic compromise for patients during the fabrication period. Chairside tooth replacement is an excellent application of fiber-reinforced composite resin technology. This article presents an innovative, affordable chairside procedure in which Ribbond Multi-Purpose Bondable Reinforcement Ribbon is used to replace a single extracted anterior tooth using the patient's own tooth. 相似文献
12.
Maria Pia Francescato P. Cok O. Radillo B. de Bernard 《Journal of human nutrition and dietetics》1988,1(5):321-327
A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision. 相似文献
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新型骨与软骨组织工程支架材料制备及其性能研究 总被引:14,自引:1,他引:13
目的:研究符合骨与软骨组织工程制备技术要求的新型支架复合材料;并确定其性能与结构优化设计的主要参数指标。方法:按不同CPPf(聚磷酸钙纤维)/PLL(L-聚乳酸)重量比及相同CPPfPLLA/NaCl颗粒重量比,采用溶铸颗粒沥取(Solventcasting particulte-leaching)法轩系列CPPf/PLLA支架复合材料;液体置换法,压缩性能测试及扫描电子显微镜观察其密度,孔隙度压缩模量及微结构特征;材料样品体外人工降解液直接浸渍法判定其生物降解性能,并观测其生物降解率,压缩碍及微结构由微孔海绵状过渡为纤维网状。随着支架材料在人工降解液中降解时间的延长,其降解率以0%-13.2%线性递增;压缩模量呈线性降低至1.10-2.78MP;材料横截面微结构则发生相应改变。结论 CPPf/PLLA支架复合材料具有高孔隙度的三维立体结构,良好的抗压缩性能和和解性能,经进一步优化设计后,可成为结构和性能符合各项要求的新与软骨组织工程支架材料。 相似文献
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尼莫地平复方丹参注射液治疗新生儿缺氧缺血性脑病疗效观察 总被引:1,自引:0,他引:1
目的观察尼莫地平联合复方丹参注射液治疗新生儿缺氧缺血性脑病(HIE)的疗效.方法 128例HIE患儿随机分为复方丹参注射液组32例,尼莫地平组,尼莫地平加复方丹参注射液,与对照组.结果复方丹参注射液组、尼莫地平组、尼莫地平加复方丹参注射液治疗组总有效率分别为81.3%(26/32)、80.0%(24/30)、97.1%(34/35),对照组总有效率为51.6%(16/31),P<0.05.结论尼莫地平与复方丹参注射液在治疗HIE时有协同作用,疗效显著,未见副作用发生. 相似文献
17.
Lasse Kanerva Maj-Len Henriks-Eckerman Tuula Estlander Riitta Jolanki Kyllikki Tarvainen 《Journal of the European Academy of Dermatology and Venereology》1994,3(2):157-168
Background Dentin-bonding systems contain sensitizing acrylates. They are increasingly used in dentistry, but only few cases of allergy have been encountered. Objective This study reports observations on eleven patients sensitized by acrylates in dentin-bonding compounds. Furthermore, the composition of dentin-bonding products was analysed and compared with the information given in the material safety data sheets. Methods Patch testing was performed to reveal allergic contact dermatitis, and chamber provocation tests to reveal possible respiratory sensitivity. Gas chromatography/mass spectrometry was used to analyse the chemical composition of the bonding products. Results The most common sensitizer in our material of eleven patients was 2-hydroxyethyl methacrylate (2-HEMA). Another putative sensitizer, BIS-GMA, used in dentin adhesives, did not cause sensitization. The typical allergic dermatitis localized to the fingertips (pulpitis). Seven of the eleven patients also developed paresthesia of the fingertips. One patient with positive patch test reactions to (meth)acrylates had pharyngitis hut no skin symptoms. One patient was sensitized because she had been patch tested with too high a concentration (undiluted) of dentin-bonding components. Material safety sheets gave inaccurate or wrong information about the contents. Conclusion Dentin-bonding acrylates are strong sensitizers, and even a single exposure may sensitize. 相似文献
18.
复合树脂作为临床常用牙科充填材料存在耐磨性差、聚合收缩大和牙本质边缘适应性不佳等问题。近年有研究发现预热可以改善复合树脂的性能,本文就预热复合树脂对其单体转化率、边缘微渗漏、机械性能以及牙髓的影响等方面进行探讨,以供临床参考。 相似文献
19.
目的观察深度烧伤和瘢痕切除创面进行猪脱细胞真皮与自体刃厚皮一步法与两步法复合移植的临床效果。方法2000年4月~2002年12月间用猪脱细胞真皮与自体刃厚皮复合移植修复深度烧伤创面或瘢痕切除创面16例,对一步移植法和两步移植法进行比较。结果一步移植法中,4例植皮完全成活,3例植皮95%以上成活,1例植皮80%成活;两步移植法中,5例植皮完全成活,3例植皮95%以上成活。均无1例补植皮。随访6个月~2年,一步和两步移植法中的复合移植皮肤外观、质地基本接近正常皮肤,瘢痕增生不明显。结论猪脱细胞真皮与自体刃厚皮复合移植是深度烧伤创面、瘢痕切除创面的良好修复材料,一步移植法可行、简便、实用。 相似文献
20.
Scott R. Dyer John A. Sorensen Lippo V.J. Lassila Pekka K. Vallittu 《Dental materials》2005,21(12):1104-1110
OBJECTIVES: Damage mechanics has been defined as the study of the initiation (initial failure) and accumulation of damage to and including rupture (final failure). This study was designed to evaluate the effect of increasing fiber-reinforced composite (FRC) substructure within a standardized fixed partial denture (FPD) model on the failure performance, in terms of damage mechanics. METHODS: The two FRC restorative systems, Targis/Vectris (TV) (Ivoclar Vivadent) and EverStick (ES) (Stick Tech with Gradia, GC Corp.), were used to restore the molar FPD model (1.5 mm axial and 2.0 mm occlusal reduction). Templates were used to standardize substructure designs with 0, 18, 43, and 66% cross-sectional FRC volume fraction (V(FRC)) of fiber substructure. Specimens (n = 5) were homogenized at 29 points and stored for 1 week at 37 degrees C in distilled water. Specimens were luted with calcium hydroxide, then statically loaded until failure. Initial failure (IF), final failure (FF) and the mode of failure were recorded. RESULTS: The lowest mean load to initial failure was 530 N (TV 18%) and the highest was 1208 N (ES 66%). Linear regression analysis calculated the Pearson's correlation coefficient (r) for the interactions between V(FRC) and IF (ES: r = 0.7879, TV: r = 0.6184), V(FRC) and FF (ES: r = 0.912, TV: r = 0.8152), and between IF and FF (ES: r = 0.892, TV: r = 0.7237). Unreinforced specimens universally fractured instantaneously. SIGNIFICANCE: The highest loads to initial and final failure were yielded by specimens with the highest cross-sectional V(FRC). 相似文献