Study on unpolymerized area in the surface layer of light activated composite resins

本研究的目的是确定表面未聚合层的实际情况，并制定相应的临床对策。因此，首先对表面未聚合层进行了研究，得到以下结果：在树脂初始固化后，修复体的固化程度随着时间的推移而继续增加，但未聚合层在修复体表面继续聚合，这可能是表面降解的原因。许多临床程序;尝试了使用基质、延长照射时间、在光单元端部上使用白色尖端保护器等，这些技术先前被报道用于提高修复体表面上的固化程度。不幸的是，表面区域的固化程度显著提高，但不能防止层的出现。最好的方法是通过精加工和抛光工序去除涂层， ...更多信息 这一刻。因此，为了确定未聚合层的实际范围，必须借助于努普硬度测量作为参数来检测商业产品的表面区域中的相对适当固化的面积。因为，未聚合或未充分固化的区域可能出现在表层。从照射表面正下方的区域到沿照射方向的沿着深度进行努普硬度测量，以获得硬度-深度曲线。根据曲线上的峰值硬度，可以确定必须通过抛光去除的树脂产品的深度。结论如下：首先，光活化复合树脂应在腔中过量填充（约0.5mm）。初凝后，必须通过精加工或抛光程序去除多余的材料。因此，可以在修复体上暴露具有最佳表面纹理的表面。少

The purpose of this study was to determine the actual situation of the unpolymerized layer in the surface area and make up some clinical counterplan for it. Therefore, Firstly, the study on the unpolymerized layer in the surface was conducted.The following results were obtained. After initial setting of the resin, the degree of cure for the restoration continues to increase with time, but the unpolymerized layer continuously remaines at the surface of restoration, that might be the cause of surface degradation. Many clinical procedures ; using a matrix, prolonged irradiation time, using a white tip protector on the light unit end, and so on , which techniques were previously reported to improve the degree of cure on the surface of the restoration, were attempted. Unfortunately, the degree of cure at the surface area was remarkably improved but the apperance of the layer could not be prevented. It is the best way that the removal of layer by finishing and polishing procedures, at the pr … More esent moment. Therefore, in order to determine the actual range of the unpolymerized layer, the relatively properly cured area in the surface region of the commercial products has to be detected by means of the Knoop hardness measurement as a parameter. Because, the area where is unpolymerized or inadequately cured might be appeared at the surface layer. The Knoop hardness measurements were carried out from the area just below the irradiation surface to the depths along the irradiation direction, to obtain the hardness vs. depth curve. From the peak hardness on the curve, it is possible to determine the depth of resin products which must be removed by polishing.The conclusions are as follows.At first, the light activated composite resin should be overfilled ( approximately 0.5 mm ) in the cavity. After initial setting, the excess material must be removed by finishing or polishing procedure. Consequently, it is possible to expose the surface having the best surface texture on the restoration. Less