Oberholzer Theunis G, Grobler Sias R, Rossouw Roelof J, Kotze Theuns J
Oral and Dental Research Institute, School for Oral Health Sciences, University of Stellenbosch, Tygerberg, South Africa.
SADJ. 2003 Mar;58(2):48-53.
Polymerisation shrinkage and the associated stress on composite resins and surrounding structures have been regarded as a major cause of leakage and clinical failures in modern polymer restorations. The purpose of this study was to investigate the effect of an additional flowable compomer layer on the microleakage of Class V dental cavities, which were further filled with a compomer.
Cavities (32) were prepared in human premolars, conditioned with a non-rinsing agent (Prime & Bond NRC) and treated with the bonding agent (Prime & Bond NT). Sixteen of these cavities were then lined with a layer of flowable compomer (Dyract Flow, approximately 0.5 mm) and further filled with Dyract AP. The other 16 cavities were filled without the flowable compomer. The specimens were thermo-cycled in a 0.5% basic fuchsin solution, sectioned and evaluated for dye penetration using a scoring system of 0 to 4.
Lower microleakage values were found at the enamel as well as at the dentine sides when a layer of Dyract Flow was used as a liner. Furthermore, significantly (p < 0.05) lower microleakage was found in enamel than in dentine for both layered and unlayered restorations.
It can be concluded that a layer of flowable compomer (i.e. Dyract Flow) in a cavity under a compomer may be recommended to improve the marginal seal of a restoration.
聚合收缩以及复合树脂和周围结构上的相关应力被认为是现代聚合物修复体中渗漏和临床失败的主要原因。本研究的目的是调查额外的可流动复合共聚体层对Ⅴ类牙洞微渗漏的影响,这些牙洞进一步用复合共聚体填充。
在人类前磨牙上制备32个洞,用非冲洗剂(Prime & Bond NRC)进行预处理,并用粘结剂(Prime & Bond NT)进行处理。然后,其中16个洞用一层可流动复合共聚体(Dyract Flow,约0.5毫米)衬里,并用Dyract AP进一步填充。另外16个洞不使用可流动复合共聚体进行填充。将标本在0.5%碱性品红溶液中进行热循环,切片,并使用0至4的评分系统评估染料渗透情况。
当使用一层Dyract Flow作为衬里时,在釉质和牙本质侧均发现较低的微渗漏值。此外,对于分层和未分层修复体,釉质中的微渗漏明显(p < 0.05)低于牙本质。
可以得出结论,对于复合共聚体修复下的牙洞,推荐使用一层可流动复合共聚体(即Dyract Flow)来改善修复体的边缘封闭性。