Statement of Problem: Panoramic radiography seems necessary at examination, diagnosis and treatment plan phases of removable prostheses treatment since most of the patients who request removable prostheses treatment have retained root fragments, impacted teeth, cycts and tumors that might not otherwise be detected.
Purpose: The aim of the present study was to investigate the incidence rate of retained roots, impacted teeth and suspected pathologic conditions in panoramic radiographics of patients referred to removable prosthodontics departments of four dental schools and five public centers.
Materials and Methods: In this case series study, 1232 panoramic radiographs were analyzed to detect retained root fragments, impacted teeth and pathologic conditions.

Results: From among 850 panoramic radiographs of patients seeking complete denture, the incidence rates of impacted teeth, retained roots and pathologic lesions were 1.3%, 9.5% and 4.0% respectively.Also from 382 panoramic radiographs of removable partial denture patients the corresponding measures were 2.9%, 11% amd 0.1%.
Conclusion: Due to the significant and evident problems in residual ridge, as well as pathologic conditions of the remaining teeth structures and their supporting tissues as partial prosthesis base, the necessity for panoramic radiographics in edentolous and semi- edentulous patients is reemphasized.