Effect Of X-ray On The Topographical Properties Of Human Teeth

Objectives: Objectives: Rapid tooth loss occurs from radiotherapy, which is given for most malignant cancer treatment. In fact, it is the major cause of tooth loss. This study was performed with the intentions of finding out how much damage the exposure to radiation causes to the topography of human enamel and dentine.
Methods: Methods: Human third molars (n=50) randomly placed into five different tests, including a controlled group (no radiation). Energy of high level X-rays were exposed to the test groups (2Gy/day, 5days/week; including a 10Gy group, a 30Gy group, a 50Gy group, and a 70Gy group), tested (0.5N/m, 24⁰C, 35%H) by Atomic Force Microscopy (AFM), the 3D surface topography images were taken (1Hz, 256lines), and statistically analyzed (ANOVA ,Kolmogorov-Smirnov and Shapiro-Wilk, T-test, p<0.05).
Results: Results: The results of the radiation dose-response analysis for enamel and dentine indicated a statistically significant change with dose. The 3D morphological images of the irradiated groups were shown that the crystals on sound human enamel（Fig.1b）and dentine(Fig.1a) surface revealed a series of orderly particles, arranged and closely contacted while irradiated sites showed increasing cracks and arranged disorderly with unclear outline, there had also been an increase in the troughs, and in the height of each peak(Fig2,3). Properties of the surface topography for the enamel and dentine revealed a significant response relationship to the dosage given (P<0.05).
Conclusions: Conclusion: Once the teeth were exposed to the radiation their surface roughness not only increased, but were also prone to the micro-tensile, and reduced strength. Furthermore, the changes in the topographical areas of the hard dental tissue was susceptible to the increase of caries, on the other hand, the hard dental tissue could possibly lead to a quick development of caries.