Anatomy Flashcards
(45 cards)
What is lamina dura?
teeth sockets are bounded by thin radiopaque layer of dense bone
– continues over crest of alveolar bone
What is alveolar crest? Where?
gingival margin of alveolar process between teeth (radiopaque line)
*continuous with lamina dura
– 1-2mm from crown/CEJ
What is the periodontal ligament space?
radiolucent space between the tooth root & lamina dura
*the constant pressure to bone surrounding root makes it more sclerotic/dense
What can a double PDL mean?
- convexity of proximal root surface
- two roots
What is cancellous/trabecular bone?
between cortical plates in both jaws
What pathologies can alter bone metabolism/trabeculation?
anemia, osteonecrosis, osteopetrosis
What is the anterior nasal spine?
- radiopacity at or just below junction of inferior end of nasal septum & inferior outline of nasal aperture
What structure meets at the anterior nasal spine?
floor of nasal cavity
What structure is superior to anterior nasal spine?
nasal septum
What is the intermaxillary suture?
“median suture”
- extends from alveolar crest between 8&9 posteriorly to distal aspect of hard palate
- uniform width
- variable shape (xray angulation)
What is the nasopalatine canal? What & where is the entrance? Exit?
- transmits nasopalatine nerves & vessels
- superior/Stenson foramina: usually 2 round/oval foramina in floor of nasal cavity
- incisive foramen (oral opening)
What is the incisive foramen?
- oral end of nasopalatine canal
- between 8 & 9 (if xray technique proper)
- variable size/shape
What is the nasal cavity?
located above oral cavity
- floor seen as thin radiopaque line
- inverted V in anterior region & straight line in posterior
Where do we typically see the intersection of the floor of the maxillary sinus & nasal cavity?
premolar level
What is the maxillary sinus?
- air-containing cavity lined with mucous membrane
- borders appear in PA radiographs as thin, irregular radiopaque lines
- may have septae
How does the nose appear in radiographs?
- soft tissue tip can be seen in projections of maxillary incisors superimposed over roots
- radiopaque entity
What is the lateral fossa?
– depression of maxilla near apex of lateral incisor
- diffuse radiolucency
What is the nasolacrimal canal?
- runs from orbit inferiorly to nasal cavity
**should NOT be seen in regular/good PA
Where can the nasolacrimal canal be seen? What shape?
- occasionally near apex of maxillary canine when steep vertical angulation is used (PA)
- lateral to maxillary molar; oval (occlusal)
What is the zygomatic process of the maxilla?
- radiopaque extension of the lateral maxillary surface that articulates with the maxillary process of the zygoma
What shape is the zygomatic process of the maxilla on a radiograph?
U shaped
What is the posterior extension of the zygomatic process of the maxilla?
- zygomatic bone
What is the nasolabial fold?
- oblique line demarcating a region that appears to be covered by a veil of slight radiolucency
- often traverses PA radiographs near premolar region
What is the pterygoid plates & hamular process?
- medial & lateral plates lie immediately posterior to tuberosity of maxilla
- process extends inferiorly from medial plate
