Dental treatment with fluoride at various stages of tumor therapeutic irradiation

摘要

Malignant tumors in the head-neck area are treated by irradiation therapy [1]. Despite a carefully planned irradiation it is inevitable, that healthy neighbouring tissue, i.e. bones, mu-cosa, teeth and even the salivary gland, is damaged by the irradiation. For the teeth, this means that shortly after the first applied irradiation doses (2 Gy) defects on the tooth substance are identified [2]. The reason for this dental damage, the so-called radiation caries [3], is primarily the structural change of the tissue caused by irradiation. The mechanical properties are significantly deteriorated; fissures and an increasing roughness of the surfaces are observed [4]. The additional change of the oral environment enhances the radiogenic caused tooth destruction due to the changed composition of saliva and the reduction of salivary flow favoring plaque, demineralization and increased carious microorganisms [2, 5] and enhances the radiogenic caused tooth destruction. The mechanical properties however change only marginally [6].Preventive normal oral hygiene will be more intense if it is combined with regular fluoridation of teeth, because a lower caries increase was observed [2]. In addition, the use of solutions containing calcium and phosphate complementary to fluoride application is recommended [7] to apply remineraliz-ing substances such as calcium and phosphate.Another approach suggested by Thiel [8] is the daily application of high-concentrated fluoride via gel carriers before beginning the radiation therapy.The aim of this study is to compare how the hardness and elasticity are affected by various preventive measures - remin-eralization after irradiation, before every radiation fraction, and during irradiation.