Radiopaque Structures - ANSWER Dense structures. Allow less radiant energy to pass
through. Electrons reach receptor with less energy. Results in white (light) image.
Radiolucent Structures - ANSWER Less dense structures. Allow radiant energy to pass
through. Electrons reach image receptor with high energy, causing dark image.
Mandible - ANSWER Single bone of lower jaw. Radiopaque.
Maxilla - ANSWER Two bones that form upper jaw and part of palate. Joined at midline
by the maxillary suture. Radiopaque.
Ramus - ANSWER Vertical portion at each end of mandible. Radiopaque.
Body of mandible - ANSWER Curved portion of mandible that connects rami. Radio-
paque.
Condyle of mandible - ANSWER Ball-like top of ramus which forms the hinge between
temporal bone and mandible. Part of TMJ. Appears in extraoral images. Radiopaque.
Midsagittal Plane - ANSWER midline, divides the body into equal left and right halves
Orbit - ANSWER Eye cavity, extraoral images. Radiolucent.
Frankfort Plane - ANSWER Imaginary line from bottom of eye socket to the ear canal.
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, Inverted Y - ANSWER Junction of lateral wall of nasal fossa and wall of maxillary sinus.
Above maxillary canine. Radiopaque.
Maxillary Sinus - ANSWER Air-filled cavity above maxillary premolar and molars. Radiolu-
cent, outline radiopaque.
Nutrient Canals - ANSWER Passageways through bone that supply teeth. Called pulp tis-
sue once they enter tooth. Radiolucent vertical lines.
Internal Oblique Ridge - ANSWER Line of bone on internal aspect of mandible. Near api-
ces of molars. Radiopaque band may run parallel to external oblique ridge.
Mandibular Canal - ANSWER Passageway through bone extending length of mandible for
inferior alveolar nerve. Radiolucent band outlined by two radiopaque lines (cortical bone lin-
ing).
External Oblique Ridge - ANSWER Radiopaque band near crown of mandibular molars.
Line of bone on external aspect of mandible.
Alveolar Ridge - ANSWER Bony ridge that contains alveoli (tooth sockets). Radiopaque.
Mental Foramen - ANSWER Two openings on mandible supplying lower lip with blood
vessels. Located in apical region of mandibular premolars. Small round radiolucent area.
Mental process - ANSWER Line of bone on external surface of anterior mandible. Thick
radiopaque band (upside down V)
Zygoma - ANSWER Cheek bone. Radiopaque on extraoral images.
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through. Electrons reach receptor with less energy. Results in white (light) image.
Radiolucent Structures - ANSWER Less dense structures. Allow radiant energy to pass
through. Electrons reach image receptor with high energy, causing dark image.
Mandible - ANSWER Single bone of lower jaw. Radiopaque.
Maxilla - ANSWER Two bones that form upper jaw and part of palate. Joined at midline
by the maxillary suture. Radiopaque.
Ramus - ANSWER Vertical portion at each end of mandible. Radiopaque.
Body of mandible - ANSWER Curved portion of mandible that connects rami. Radio-
paque.
Condyle of mandible - ANSWER Ball-like top of ramus which forms the hinge between
temporal bone and mandible. Part of TMJ. Appears in extraoral images. Radiopaque.
Midsagittal Plane - ANSWER midline, divides the body into equal left and right halves
Orbit - ANSWER Eye cavity, extraoral images. Radiolucent.
Frankfort Plane - ANSWER Imaginary line from bottom of eye socket to the ear canal.
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, Inverted Y - ANSWER Junction of lateral wall of nasal fossa and wall of maxillary sinus.
Above maxillary canine. Radiopaque.
Maxillary Sinus - ANSWER Air-filled cavity above maxillary premolar and molars. Radiolu-
cent, outline radiopaque.
Nutrient Canals - ANSWER Passageways through bone that supply teeth. Called pulp tis-
sue once they enter tooth. Radiolucent vertical lines.
Internal Oblique Ridge - ANSWER Line of bone on internal aspect of mandible. Near api-
ces of molars. Radiopaque band may run parallel to external oblique ridge.
Mandibular Canal - ANSWER Passageway through bone extending length of mandible for
inferior alveolar nerve. Radiolucent band outlined by two radiopaque lines (cortical bone lin-
ing).
External Oblique Ridge - ANSWER Radiopaque band near crown of mandibular molars.
Line of bone on external aspect of mandible.
Alveolar Ridge - ANSWER Bony ridge that contains alveoli (tooth sockets). Radiopaque.
Mental Foramen - ANSWER Two openings on mandible supplying lower lip with blood
vessels. Located in apical region of mandibular premolars. Small round radiolucent area.
Mental process - ANSWER Line of bone on external surface of anterior mandible. Thick
radiopaque band (upside down V)
Zygoma - ANSWER Cheek bone. Radiopaque on extraoral images.
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