Schratter-Sehn A U, Schmidt W F, Kielhauser R, Langer H, Kärcher K H
Abteilung für Strahlentherapie, Kaiser-Franz-Josef-Spital, Wien.
Strahlenther Onkol. 1992 Jan;168(1):35-8.
In patients with metallic dental fillings radiation therapy to the oral cavity can cause mucous membrane lesions, which are more severe than expected. They appear as circumscribed erosions, opposite to metallic fillings and are caused by an increase in radiation dose through secondary radiation due to the higher density and atomic number of the filling material. This dose increase can be directly measured with 0.1 mm thin sheets of graphite-loaded TLD's (LiF, Vinten). For Co-60 gamma rays a commercial amalgam filling caused a dose increase by a factor of 1.7. The half value layer for this additional radiation was measured to be approximately 0.4 mm tissue. In order to avoid painful mucous membrane ulcerations which are even more a problem if hyperfractionated treatment schedules are used, we constructed individual dental shields for each patient. As shielding material we used a dental impression material (Optosil P+1 Bayer). This method was tested in 35 patients, in all of them circumscribed mucous membrane ulcerations could be avoided. The method proved to be fast and simple and was very well tolerated by all patients.
对于有金属牙填充物的患者，口腔放疗会导致比预期更严重的黏膜损伤。损伤表现为与金属填充物相对应的局限性糜烂，是由于填充物材料的较高密度和原子序数通过二次辐射导致辐射剂量增加所致。这种剂量增加可用0.1毫米厚的含石墨热释光剂量计（LiF，Vinten）薄片直接测量。对于钴-60伽马射线，一种市售汞合金填充物使剂量增加了1.7倍。测得这种额外辐射的半价层约为0.4毫米组织。为避免疼痛的黏膜溃疡（如果采用超分割治疗方案，这一问题会更严重），我们为每位患者制作了个性化牙罩。我们使用一种牙科印模材料（Optosil P+1拜耳公司）作为屏蔽材料。该方法在35名患者中进行了测试，所有患者均避免了局限性黏膜溃疡。该方法证明快速简便，所有患者都能很好耐受。
