Acute systemic DNA damage-related biomarker responses in adult orthodontic patients following radiographic investigations.

Ionizing radiation is a potent genotoxic carcinogen. In this study, acute DNA damage-related biomarker responses were evaluated in peripheral blood lymphocytes of adults undergoing radiographic investigations for orthodontic treatment. Patients (n = 22) for orthodontic treatment were divided into two groups: Group 1 - conventional radiographs (Orthopantomogram (OPG), Lateral Cephalogram (LC) and two Intra-oral periapical radiographs); Group 2 - Cone Beam Computed Tomography (CBCT). Peripheral blood samples (3 mL) were collected before and after radiography imaging. Gamma-H2AX (γ-H2AX) focus formation, micronucleus (MN) formation, and ferredoxin reductase (FDXR) gene expression were evaluated as biomarkers of exposure and response. The frequency of γ-H2AX focus and micronuclei increased significantly (p < 0.05 and p < 0.001) from pre- and post-radiography in both groups. FDXR showed significant upregulation and downregulation in Groups 1 and 2, respectively indicating divergent early transcriptional response between the groups. Conventional radiographs and low-dose CBCT exerted acute DNA damage-related biomarker responses in adult orthodontic patients. FDXR gene showed greater upregulation with conventional radiographs than CBCT. Group 1 and group 2 post-radiography showed no statistical difference when assessed with the three biomarkers for acute damage. Future studies with larger samples and long-term follow-up are needed to validate the findings and provide a basis for safety recommendations.