Lecture 2 (chapter 27) Normal Radiographic Landmarks

Question 1

This is the air-filled radiolucent area inside the nasal cavity.

Answer 1

nasal fossa

Question 2

This is the thin line of bone that separates the right and left nasal cavities. In the radiograph, it appears as a radiopaque line.

Answer 2

nasal septum

Question 3

This is a thin line of bone that forms the lower boundaries of the nasal fossae. This structure appears as a curved, radiopaque line.

Answer 3

floor of nasal cavity

Question 4

This structure appears as a thin, radiolucent line between the central incisors. This line represents the area where the bony plates come together to form the palate.

Answer 4

midline suture

Question 5

The nose can be seen as a soft tissue shadow, usually radiopaque, along the roots of the maxillary incisors.

Answer 5

shadow of the nose

Question 6

This structure appears as a radiopaque area at the base of the nasal septum. It represents a bony protuberance to which the nasal cartilage is attached.

Answer 6

anterior nasal spine

Question 7

This structure is an opening through which the nasoplatine nerves and artery pass. This area appears as a radiolucent, oval-shaped structure between the central incisors. Also called nasopalatine foramen.

Answer 7

Incisive foramen

Question 8

This appears as a radiolucent area between the lateral incisor and the canine. This structure represents a depression in the surface of the maxilla in that area.

Answer 8

lateral fossa

Question 9

This is a radiopaque line separating the nasal fossa and the maxillary sinus that appears around the maxillary canine region.

Answer 9

Anterior wall of the maxillary sinus

Question 10

This fossa may be seen in the canine region because of an indentation in the surface of the maxillary in that area (this is also known as the lateral fossa).

Answer 10

Canine fossa

Question 11

This is a “Y” shaped, radiopaque line that represents the intersection of the nasal cavity wall and the maxillary sinus wall

Answer 11

Inverted Y

Question 12

This structure is seen as a thin, radiopaque line that represents the front wall of the maxillary sinus.

Answer 12

Inferior border of the maxillary sinus

Question 13

This is an air-filled space above the maxillary premolars and molars and appears radiolucent.

Answer 13

Maxillary sinus

Question 14

This radiopaque ‘U’ shape appears superimposed over the maxillary molars and represents the bony structure that joins the maxilla and the zygoma.

Answer 14

Zygomatic process of the maxilla

Question 15

This bony structure appears as a bulge distal to the maxillary molars and at the end of the maxillary alveolar ridges.

Answer 15

Maxillary tuberosity

Question 16

This bony projection, which appears radiopaque and extends downward from the medial pterygoid plate, is located behind the maxillary tuberosity region.

Answer 16

Hamulus

Question 17

This thin, radiopaque line is often seen over the maxillary premolar area

Answer 17

Floor of the nasal fossa

Question 18

This structure may be seen in a molar projection that is placed extremely to the distal. It appears as finger-shaped projection extending upward from the mandible distal to the maxillary molars.

Answer 18

Coronoid process of the mandible

Question 19

These thin, radiopaque lines appear within the sinuses and represent bony walls that form the compartments of the sinuses

Answer 19

Sinus septum

Question 20

If mandibular radiograph is exposed using an extreme negative angulation, it can be seen as a radiopaque ridge below the anterior teeth.

Answer 20

Inferior border of the mandible

Question 21

This structure appears as a tiny, radiolucent hole below the roots of the mandibular central incisors. This foramen provides an opening through which a small blood vessel is able to pass.

Answer 21

Lingual foramen

Question 22

These bony projections surround the lingual foramen and appear as a radiopaque ring around it.

Answer 22

Genial tubercles

Question 23

The mental ridge is a bony prominence on the external portion of the mandible which extends in a sloping fashion from the premolar area to the central incisors. It appears as a radiopaque, curved ridge below the mandibular anterior teeth.

Answer 23

Mental ridge

Question 24

These can be seen as radiolucent lines extending downward from the mandibular anterior teeth. These canals provide a mean for the blood vessels and nerves to reach the teeth

Answer 24

Nutrient canals

Question 25

Often this soft tissue can be seen as a radiopaque, curved line that appears below the crowns of the mandibular teeth.

Answer 25

Lip line

Question 26

Bony protuberances often seen as small, rounded, radiopaque areas superimposed on the roots of the teeth in the canine and premolar regions of the mandible.

Answer 26

Mandibular tori

Question 27

This structure provides a means for the blood vessels and nerves to supply the lower lip. It appears as a radiolucent, round- or oval-shaped area located near the apices of the mandibular premolars. This structure is often misinterpreted as some type of periapical lesion.

Answer 27

Mental foramen

Question 28

This canal extends the length of the mandible and provides a passageway for blood vessels and nerves. It appears as a radiolucent band following the roots of the mandibular posterior teeth.

Answer 28

Mandibular canal

Question 29

This ridge is a bony prominence that provides an attachment site for the mylohyoid muscle to the internal surface of the mandible. It is seen as a wide, curved, radiopaque line extending downward and anteriorly in the molar region. It is often superimposed over the roots of the molar teeth. Also called the internal oblique ridge.

Answer 29

Mylohyoid ridge

Question 30

This ridge provides an attachment site for the buccinator muscle. It appears as a wide, curved, radiopaque line that travels down from the ramus of the mandible to near the third molar teeth

Answer 30

External oblique ridge

Question 31

This is a depressed area on the lingual side of the mandible. It appears radiographically as a radiolucent area below the internal oblique ridge.

Answer 31

Submandibular fossa