Direct radiation-induced effects on dental hard tissue

Area of Science:

• Dental research
• Radiation oncology
• Materials science

Background:

• Radiation caries is a common radiotherapy complication, causing enamel erosion and dentin exposure.
• The precise mechanisms behind radiation caries development remain unclear.
• This study investigates the direct impact of radiation on dental hard tissues.

Purpose of the Study:

• To evaluate direct radiation effects on dental hard tissue.
• To understand the role of these effects in radiation caries formation.

Main Methods:

• Third molars were irradiated at 0, 30, and 60 Gy.
• Microhardness, elastic modulus, microstructure, and crystal properties were analyzed.
• Techniques included Vickers microhardness testing, atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray diffraction, and Raman microspectroscopy.

Main Results:

• Significant decreases in enamel microhardness and elastic modulus were observed at 30 and 60 Gy.
• Radiation caused enamel microstructure destruction, particularly near the dentino-enamel junction (DEJ).
• Enamel showed greater crystallinity reduction and an increased protein/mineral ratio compared to dentin.

Conclusions:

• Radiation directly impacts dental hard tissue properties, including mechanical, micro-morphological, crystalline, and chemical characteristics.
• Early destruction of enamel near the DEJ and reduced enamel crystallinity are linked to radiation caries.
• Findings highlight radiation's direct role in altering tooth structure, contributing to caries development.