Impact of imaging protocol and tube current adjustment on the radiation dose in CBCT imaging of mandibular incisors.

OBJECTIVES

This study aimed to assess the impact of imaging protocols involving tube current (mA) adjustment on the equivalent and effective radiation dose for cone-beam computed tomography (CBCT) of mandibular incisors using the corresponding periapical radiography as clinical reference.

METHODS

An anthropomorphic head and neck phantom equipped with 24 thermoluminescent dosimeters (TLDs) was used to evaluate radiation exposure across seven imaging protocols: high-dose CBCT (4.0, 7.1, and 10 mA), low-dose CBCT (3.2, 4.5, and 6.3 mA), and standard periapical radiography (7 mA). Equivalent and effective radiation doses were calculated according to tissue-weighting factors outlined in ICRP Publication 103.

RESULTS

Effective dose increased proportionally with tube current, ranging from 53 to 175 µSv in high-dose protocols and from 8.6 to 18 µSv in low-dose protocols. Periapical radiography yielded the lowest effective dose (1.4 µSv). The highest equivalent doses were recorded for the salivary glands and oral mucosa across all protocols.

CONCLUSIONS

CBCT protocols with reduced tube current significantly decrease radiation exposure. The lowest setting tested (3.2 mA) resulted in an effective dose comparable to six periapical radiographs. These findings support the implementation of low-dose CBCT for complex endodontic diagnostics, particularly during initial evaluations, in alignment with the ALADAIP principle.