Assessment of Cytotoxicity, Genotoxicity

Yaxin Wang60 enrolled

Overview

Goal: The goal of this observational study is to evaluate the genotoxic and cytotoxic effects of OPG and CBCT on exfoliated buccal mucosal cells Main question: Does CBCT cause greater genotoxic and cytotoxic effects on buccal mucosal cells compared with OPG? Buccal epithelial cells were gently exfoliated from participants scheduled to undergo OPG or CBCT imaging. Samples were collected twice-immediately before exposure and again 10-12 days afterward. All participants provided written informed consent prior to inclusion in the study.

Study Type

OBSERVATIONAL

Enrollment

Conditions

Genotoxicity Cytotoxicity Ionizing Radiation Exposure Dental X-Ray Exposure

Eligibility

Sex: ALLMin age: 15 YearsMax age: 50 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: Underwent routine dental imaging using OPG or CBCT (no additional radiation for research purposes). Age 15-25 years or 40-50 years at the time of enrolment. Able and willing to provide written informed consent (or consent from a legal guardian for minors). Agreed to provide pre-exposure and follow-up buccal epithelial cell samples. Exclusion Criteria: History of systemic diseases, including but not limited to leukemia, lymphoma, rheumatic disorders, or diabetes mellitus. Prior exposure to head-and-neck radiotherapy, immunosuppressive drugs, or cytotoxic medications. Presence of active infectious diseases or acute/chronic inflammatory conditions at the time of enrolment. Clinically visible oral pathological lesions, including mucosal abnormalities, gingivitis, or periodontitis. Use of removable intra-oral prostheses or appliances (e.g., dentures, orthodontic appliances). Engagement in smoking, alcohol consumption, or betel-nut chewing. Diagnostic or therapeutic X-ray exposure within the preceding 3 months. Previous or current oral mucosal diseases, including oral lichen planus, recurrent aphthous stomatitis, oral candidiasis, HSV infection, leukoplakia, oropharyngeal carcinoma, mucous membrane pemphigoid, or pemphigus vulgaris. Presence of persistent local irritants, including ill-fitting dental prostheses, sharp teeth/restorations, chemical irritation (acidic foods, alcohol-based mouthwash), or recurrent thermal injury.

Outcomes

Primary Outcomes

Primary outcome: Change in micronucleated buccal epithelial cells measured by the Buccal Micronucleus Cytome Assay (MN per 2,000 cells)

Micronucleated buccal epithelial cells will be quantified using the Buccal Micronucleus Cytome Assay following Sarto et al. (1987) criteria. For each participant, 2,000 exfoliated buccal cells will be evaluated at two time points: 1. immediately before dental X-ray exposure, and 2. approximately 10 ± 2 days after exposure. The primary analysis will report the change in the number of micronucleated cells per 2,000 cells (post-pre difference). Micronuclei are identified based on size, morphology, staining characteristics, and separation from the main nucleus. Higher post-pre values indicate greater genotoxic response.

Time frame: 10 ±12 days after exposure