Background: This study aimed to estimate and compare the absorbed dose, lifetime cancer risk and mortalities due to cone-beam computed tomography (CBCT) and panoramic examinations on patients. Materials and Methods: The exposure factors were applied to 332 patients in two age groups (6-10, and ˃18-year-old). The dose-area product (DAP) values were measured for CBCT and panoramic radiographies. Organ absorbed doses and effective doses were calculated based on the collected parameters applying PCXMC software. The risk of exposure-induced death (REID) and cancer risks were estimated by BEIR VII phase 2 model at different age groups and genders for the two dental radiography modalities. Results: Salivary glands was the largest contribution of the organ absorbed dose and effective dose in both CBCT and panoramic radiographies. The mean (±SD) REID values (per ten million) in CBCT were obtained at 35.6±5.2 for females and 29.01±1.8 for males, in the pediatric group, and were 31.1±2.2 for females and 25.71±2.02 for males in the adult group for all cancers. In addition, these values for panoramic radiography were 10.2±1.2 and 6.61±1.2 for women and men, respectively, in the pediatric group, and were 5.3±1.06 and 3.01±1.12 in the adult group. The mean REID values were higher significantly in CBCT compared to panoramic, and also in the pediatric than adult groups (p˂0.05). Conclusion: CBCT had a significantly higher level of radiation risks compared to panoramic radiography. Therefore, clinicians should request CBCT examinations by considering their determents and benefits.