Wilner F J, Oliver R G
Department of Dental Health and Development, Dental School, Heath Park, Cardiff CF4 4XY, UK.
J Orthod. 2000 Sep;27(3):261-6. doi: 10.1179/ortho.27.3.261.
The objective of the study was to evaluate a reproduction method that would enable the study of the enamel/ bracket/composite interface in vivo, and consisted of in vitro assessment of two different impression materials to compare reproduction of brackets bonded to extracted teeth followed by in vivo assessment of the superior material. In vitro standard edgewise brackets were bonded to two extracted teeth and impressions were taken using two different types of low viscosity silicone-based impression materials. A medium viscosity silicone impression material was used to support the original impression. Three impressions of both the gingival and occlusal aspect of the bracket base region were obtained using each of the impression materials. Replicas were then prepared for SEM viewing and these compared to SEMs of the real teeth for reproduction of detail. A 3-point Reproducibility Index was used to compare the SEM photographs of the comparable replicas. One impression material was clearly superior to the other and produced an acceptably accurate representation of the true clinical situation in three out of four samples. This material also performed well in the in vivo situation. The technique described is satisfactory for the production and analysis of SEM pictures of the enamel/composite/ bracket base interface in vivo.
本研究的目的是评估一种能够在体内研究牙釉质/托槽/复合材料界面的复制方法，该方法包括对两种不同印模材料进行体外评估，以比较粘结在拔除牙齿上的托槽的复制情况，随后对性能更优的材料进行体内评估。在体外，将标准方丝弓托槽粘结到两颗拔除的牙齿上，并使用两种不同类型的低粘度硅基印模材料制取印模。使用中粘度硅基印模材料辅助原始印模。使用每种印模材料对托槽基部区域的牙龈和咬合面各制取三个印模。然后制备复制品用于扫描电子显微镜（SEM）观察，并将其与真实牙齿的SEM图像进行比较，以评估细节的复制情况。使用三点再现性指数比较可比复制品的SEM照片。一种印模材料明显优于另一种，并且在四个样本中的三个样本中能够对真实临床情况做出可接受的准确呈现。这种材料在体内情况下也表现良好。所描述的技术对于体内牙釉质/复合材料/托槽基部界面的SEM图像的制作和分析是令人满意的。
