One of the most challenging factors affecting impression quality and good marginal fit is the gingival retraction method, which aims to separate the gingiva from the tooth to expose the finishing line of the prepared ...One of the most challenging factors affecting impression quality and good marginal fit is the gingival retraction method, which aims to separate the gingiva from the tooth to expose the finishing line of the prepared tooth. Bleeding and contamination from the crevicular fluid may compete for space with the impression material within the sulcus, leading to indistinct preparations and a lack of detail at the margin. In addition, such procedures might damage the PDL and cause permanent recession. Flowable composite cable, as opposed to traditional retraction cords, offers the proper marginal seal and visibility during the impression record because of its lower viscosity, improved adaptability, and elastic properties. The aim of this report is to present a brand-new, innovative method for controlling gingival hemorrhage in addition to the gingival retraction in restorative and prosthodontic treatment by utilizing a flowable composite during the final impression record procedure. In these case reports, the flowable composite cord technique is used instead of traditional gingival cords to modify and refine the gingival tissue before taking the traditional final impression or digital scan. Two cases were done for patients undergoing fixed prosthodontics and veneer treatment within a 2-year follow-up period. In addition, the flowable composite cord was used as temporary restoration before the final prosthetic cementation or under the provisional crowns. As a result, clean and healthy gingival tissues render cementation of the final prosthesis quicker and easier to perform. The patients in both cases claimed that their prosthodontic treatments, which involved the application of a flowable composite cord to temporarily retraction the gingiva, had produced good outcomes at the yearlong follow-up. In conclusion, the flowable composite cord technique is found to be a useful tool to improve the quality of impressions in fixed prosthodontics by providing excellent access for impression material to record fine details of the fin展开更多
文摘One of the most challenging factors affecting impression quality and good marginal fit is the gingival retraction method, which aims to separate the gingiva from the tooth to expose the finishing line of the prepared tooth. Bleeding and contamination from the crevicular fluid may compete for space with the impression material within the sulcus, leading to indistinct preparations and a lack of detail at the margin. In addition, such procedures might damage the PDL and cause permanent recession. Flowable composite cable, as opposed to traditional retraction cords, offers the proper marginal seal and visibility during the impression record because of its lower viscosity, improved adaptability, and elastic properties. The aim of this report is to present a brand-new, innovative method for controlling gingival hemorrhage in addition to the gingival retraction in restorative and prosthodontic treatment by utilizing a flowable composite during the final impression record procedure. In these case reports, the flowable composite cord technique is used instead of traditional gingival cords to modify and refine the gingival tissue before taking the traditional final impression or digital scan. Two cases were done for patients undergoing fixed prosthodontics and veneer treatment within a 2-year follow-up period. In addition, the flowable composite cord was used as temporary restoration before the final prosthetic cementation or under the provisional crowns. As a result, clean and healthy gingival tissues render cementation of the final prosthesis quicker and easier to perform. The patients in both cases claimed that their prosthodontic treatments, which involved the application of a flowable composite cord to temporarily retraction the gingiva, had produced good outcomes at the yearlong follow-up. In conclusion, the flowable composite cord technique is found to be a useful tool to improve the quality of impressions in fixed prosthodontics by providing excellent access for impression material to record fine details of the fin
文摘目的 :评估流动性双重固化复合树脂核材料在短时超高强度照射下的聚合效果。方法 :将双重固化流动性复合树脂核材料(regular dentine,Para core)注满单端开口的长方体形不透光硅橡胶模具中,将光固化灯紧贴开口端,以1000 m W/cm^2持续照射10、20 s或以3200 m W/cm^2持续照射3、6 s。试件避光保存1 h后取出,测量试件纵断面距照射光源1~10 mm间,以1 mm为间隔共10个深度的努氏显微硬度以判断聚合效果。试件继续避光保存24 h后,重复上述测量。采用SPSS 16.0软件包对数据进行统计学分析。结果:除3200 m W/cm^2、3 s光照射条件无法引发光固化反应外,在其余光照射条件下,试件在光影响深度内的硬度值在光照后24 h都显著高于单纯化学固化产生的硬度值,但光照射对试件的影响深度有限。在试件的光影响深度内,随着光照射时间的延长,试件的硬度值得到显著提高;而试件在3200 m W/cm^2、6 s和1000 m W/cm^2、20 s条件下光照射后24 h的硬度值无显著差异。结论:3200 m W/cm^2光强度照射时间必须延长到6 s,才能保证引发流动性复合树脂核材料的光固化反应,并获得合适的聚合效果。
