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Cephalometric Analysis and Radiographic Interpretation Flashcards

7 cards from real ABO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

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  1. A patient presents with SNA = 82°, SNB = 76°, and ANB = 6°. Which diagnosis best describes this patient's skeletal pattern?

    Answer: Class II skeletal relationship due to mandibular retrusion

    ANB of 6° (>4°) with normal SNA (82°) and reduced SNB (76°) indicates a Class II skeletal pattern caused by a retrognathic mandible.

  2. Which cephalometric measurement is most directly useful for evaluating a patient's vertical skeletal pattern?

    Answer: FMA (Frankfort-Mandibular Plane Angle)

    The FMA reflects the divergence between the Frankfort Horizontal and the mandibular plane, directly indicating whether the patient has a hyperdivergent, normodivergent, or hypodivergent vertical pattern.

  3. The posterior nasal spine (PNS) is used as a posterior reference to construct which cephalometric plane?

    Answer: Palatal (maxillary) plane

    The palatal plane (ANS-PNS) connects the anterior nasal spine to the posterior nasal spine, representing the inclination of the maxillary base.

  4. According to Steiner's cephalometric analysis, the ideal position of the upper central incisor relative to the NA line is:

    Answer: 4 mm ahead and 22° to NA

    Steiner's norm places the upper incisor tip 4 mm ahead of the NA line and the long axis at 22° to NA, balancing incisor prominence with profile esthetics.

  5. In McNamara's cephalometric analysis, which measurement primarily evaluates the effective length and position of the maxilla?

    Answer: Co-A (Condylion to A point) distance

    In McNamara's analysis, the Co-A distance (from Condylion to A point) measures effective maxillary length, with norms based on the patient's sex and overall facial size.

  6. The cephalometric landmark Articulare (Ar) is located at the intersection of which anatomical structures?

    Answer: Posterior border of the mandibular ramus and the inferior surface of the cranial base

    Articulare is defined as the intersection of the posterior border of the mandibular ramus (or condylar neck) with the inferior border of the cranial base, used when the condyle is not well visualized.

  7. The cephalometric landmark Pogonion (Pg) is defined as which point on the mandibular symphysis?

    Answer: Most anterior point of the bony chin on the mandibular symphysis

    Pogonion is the most anterior point on the curvature of the mandibular symphysis, used to assess chin prominence and mandibular protrusion.