Introduction: Dento-alveolar trauma to the maxillary incisors often requires combined clinical and radiographical follow-up. The number of radiographs can add up substantially in particular cases, which subsequently results in a higher patient’s absorbed radiation dose. As a consequence from the X-ray beam’s downward angulation, the thyroid gland potentially receives a substantial amount of radiation, both from the primary beam as from the scattered radiation. 

Aim: Assess the absorbed radiation dose by the patient’s thyroid gland by means of Personal Computer X-ray Monte Carlo calculations (PCXMC® 2.0 software), taking into account voltage, milli-Ampères, exposure time, vertical projection angle, beam collimation and age of the patient. 

Results: The use of a longer focus-to-skin distance and a rectangular collimator resulted in a significant lower radiation dose to the thyroid gland. The latter was irrespective of the patient’s age. The dose to the thyroid gland was significantly higher in younger subjects. The impact of the vertical projection angle was not similar for all age categories Conclusion: The dose to the thyroid gland seems to be mostly affected by the size of radiated surface, the focus-to-skin distance and the milli-Ampère exposure time product. The study assessed only the absorbed radiation dose by the thyroid gland under different radiographic exposures, mimicking real clinical circumstances and did not did not assess image quality. Therefore the results should be interpreted with care. 

Keywords: Dento-alveolar trauma; Radiographs; PCXMC®; Children; Thyroid glands radiation.