EFFECT OF LIMITED VOLUME CONE BEAM COMPUTED TOMOGRAPHY ON MICRONUCLEI CELLS COUNT OF BUCCAL MUCOSA

Ionizing radiation is a well-known mutagen and carcinogen in the human population which has both direct and indirect effects on the tissues. It can damage the tissues through different mechanisms like breakage, cross linking of DNA strands, change or loss of the base and disruption of hydrogen bonds. These radiations cause changes in the buccal mucosa, salivary glands, dentin and enamel leading to xerostomia, mucositis and radiation related caries.

Buccal mucosal cells are under direct radiation exposure in dental radiographic techniques and act as the primary target for radiation-induced damage. Also, it has a highly proliferative epithelial cells and can be easily collected and studied. Micronuclei, an anomaly structure, originates from the chromosome fragments or whole chromosomes that lag behind at anaphase during nuclear division under physical and chemical factors. The micronucleus index has become one of the standard cytogenetic endpoints and biomarkers used in genetic toxicology in vivo or in vitro2. In healthy epithelial tissues these MNi ranges from 0.5 to 2.5 MNi /1000 cells. The studies have shown an increase in their frequency in individuals exposed to radiation or other genotoxic agents.

However, these studies observed the effect on the micronuclei at small and medium FOV, but the radiation induced damage is seen mostly at smaller FOVs which involves high resolution, thereby causing more radiation exposure.

Keeping this in mind, the aim of this study is to observe and correlate the mean micro nucleated cell count of the buccal epithelial cells with the help of PAP smear after CBCT exposure at different voxel sizes (90 and 200) at small FOV. This could prove beneficial and shed light on the cytogenetic damage and malignant conversion potential of buccal mucosa after CBCT.