Pediatric Bitewing Exposure to Organs of the Head and Neck Through the Use of Juvenile Anthropomorphic Phantoms

Background: A literature review revealed that there is a lack of valid data on bitewing exposure dosimetry to the head and neck organs of pediatric patients. Here we are determining the actual dose to two anthropomorphic juvenile (5 yr old and 10 yr old) phantoms. Objective: To yield dosimetric measurements on the X-ray exposures to the organs of the head and neck from bitewing radiographs taken of two juvenile CIRS phantoms using round and rectangular collimation for both film and digital radiography. Methods and Materials: Two anthropomorphic CIRS juvenile phantoms (5yr old and 10 yr old) were exposed for bitewing radiographs using a Gendex 765 x-ray machine at the manufacturers pre-set film and digital pediatric settings for both rectangular and round collimation. Optically Stimulated Luminescence (OSL) dosimeters were placed in 21 head and neck pre-manufactured slots in each phantom. All exposures were repeated 15 times and divided by 15 to evaluate the average dose per view. Average organ dose calculated in micro Gray was based on 4 bitewing views. Organ fractions irradiated were determined from ICRP-89. Organ equivalent doses and overall effective doses (micro Sieverts) were based on 4 bitewing views and the ICRP-103 tissue weighting factors. Results: Radiation exposures using rectangular and round collimators were about the same for both phantoms. The effective dose in micro Sieverts for the 5 year old ranged from a low of 1.8 (digitalrectangular) to a high of 3.1 (film-round). The 10 year old ranged from a low of 1.5 micro Sieverts (digital-rectangular) to a high of 2.8 (filmrectangular) and 2.7 (film-round). Thyroid and other organ doses were low, with the highest doses seen in the glands, extrathoracic airway, and the oral mucosa. Conclusions: This was the first study utilizing juvenile CIRS phantoms in conjunction with OSL dot dosimetry to provide organ dose data from pediatric bitewing radiographs. Digital imaging and rectangular collimation along with pediatric machine settings must be used so that the ALARA concept in relation to children’s head and neck exposure may be maximized.