title: A quantitative comparison of paralleling long-cone and bisection-of-angle periapical radiography.
abstract: Quantitative data permit the variability comparison of crown-root ratios computed from periapical films of a single central incisor taken by five technicians using the bisection-of-angle and the paralleling long-cone techniques. The paralleling long-cone technique produces significantly less distortion and is less variable. It is the method of choice for assessing natural root resorption and resorption due to orthodontic therapy.
mesh_terms: D006801:Humans; D011856:Radiographic Image Enhancement; D011861:Radiography, Dental / Q000379:methods*; D012189:Retrospective Studies; D014092:Tooth Root / Q000000981:diagnostic imaging*