Comparison of dosimetry methods for panoramic radiography: Thermoluminescent dosimeter measurement versus PC-based Monte Carlo method calculation

Abstract

Purpose The purpose of this study was to evaluate the patient radiation dose of panoramic radiography calculated with PC-based Monte Carlo software (PCXMC) compared to thermoluminescent dosimeter (TLD) measurement. Appropriate input values for dose-determining factors in PCXMC were also proposed. Materials and Methods Tissue-absorbed doses and the effective dose from panoramic radiography were measured with TLD and with PCXMC under various conditions. The calculated PCXMC doses were compared with those measured with TLD.

Results The effective doses calculated with PCXMC showed differences by 9.6% to 51.2% compared to the doses measured with TLD. Reference points on Y and Z-axis were the sensitive factors when calculating effective dose. The differences between the highest and the lowest organ dose were 0.32 and 0.10 mGy respectively for PCXMC calculation and TLD measurement.

Conclusion The effective dose calculated with PCXMC was mostly higher than the dose measured with TLD, and the absorbed doses varied by organ more severely in the PCXMC calculations than in the TLD measurements. The effective dose obtained from PCXMC calculations was dependent on input values for dose-determining factors. Standard values for each dose-determining factor required to apply PCXMC to panoramic radiography were suggested in this study.