title: Effects of endodontic instrumentation using a macroradiographic subtraction technique: a preliminary investigation.
mesh_terms: D003786:Dental Pulp Cavity / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006801:Humans; D011858:Radiographic Magnification; D012390:Root Canal Therapy / Q000379:methods*; D013382:Subtraction Technique