Radiology · single question
Which radiograph is essential for orthodontic diagnosis of SKELETAL relationships?
Show answer and explanation
Correct answer: A. Lateral cephalometric
- A. CORRECT. Only the lateral cephalogram allows quantitative assessment of skeletal relationships. It is taken in a standardized, reproducible position with known magnification, permitting measurement of SNA, SNB, ANB, the mandibular plane angle, incisor inclinations and the soft tissue profile, and allowing superimposition to evaluate growth and treatment change over time.
- B. The panoramic is a valuable screening film for tooth presence, eruption, pathology and third molars, but its distortion and lack of standardization make it unsuitable for skeletal measurement.
- C. Bitewings assess interproximal caries and crestal bone levels only.
- D. Occlusal films are used for localizing impacted teeth, salivary calculi and palatal pathology — not skeletal analysis.
Note: The standard orthodontic records set: lateral cephalogram, panoramic, intraoral and extraoral photographs, and study models or a digital scan. The ceph answers the skeletal question — is this a dental or a skeletal problem, and if skeletal, is it maxillary, mandibular, or both, and in which plane of space?