Demineralization Of Enamel After Radiotherapy, In Vitro And In Situ Irradiations

Introduction: Radiogenic effects on enamel as an early stage for radiation induced caries are still discussed in controversy. The drawback of existing studies on direct radiogenic enamel degradation is the lacking comparability of the results. Objective: The aim of this study is to provide evidence for direct effects of radiation on enamel in contrast to the well-known damage post-radiationem induced in the oral environment. Material and Methods: 1: totally impacted, surgically extracted teeth (n = 10) 2: teeth irradiated in vitro (500 - 2500 Gy) (n = 20) 3: irradiated in situ (experimental enoral; 60 Gy) (n = 20) 4: radiotherapy (extraction after 18 days; 36 Gy) (n = 20) 5: radiotherapy (extraction after 2.5 years; 60 Gy) (n = 20) Demineralization: lactic acid gel (pH = 5.0) up to 270 min CLSM-histology: prospective after 0, 90, 180, 270 min etch. Interpretation of micro-morphological and micro-morphometric criteria (extension of the demineralized area) Conclusions: Enamel after radiotherapy and in vitro irradiated enamel is more vulnerable to acid attack than sound enamel. Keywords: radiotherapy, radiation caries, enamel, demineralization, in vitro