Intra Oral radiographic anatomical landmarks

Intraoral radiographic anatomic landmarks

2. Importance of knowing normal
anatomy :
1- correct film mounting requires a good
knowledge of normal radiographic anatomy.
2- To be able to detect abnormal findings.

3. APPERANCE OF THE TEETH &
SURROUNDING STRUCTURES

4. Crown
Root
Enamel
Dentin
Pulp
Teeth & Supporting
Structures
Apex
PDLS
Lamina
Dura
DEJ

5. Pulp
Horn
Chamber
Canal

6. Alveolar Crest
DEJ
CEJ
The alveolar crest appears flat and smooth bet the
teeth

7. Alveolar crest appears pointed & sharp bet the teeth

8. TYPES OF BONE SEEN IN DENTAL RADIOGRAPH:
1- CORTICAL BONE
2- CANCELLOUS BONE

9. CORTICAL BONE means outer layer
The cortical bone is also referred to as compact bone, is very
dense and contains no marrow space. This bone seen surrounding
the tooth (lamina dura) and carried over the alveolar crest.
Cortical bone resist the passage of the x-ray beam and appears
radiopaque.
CORTICAL BONE

10. Cancellous bone
Cancellous bone means arranged like a lattice
Cancellous bone is the soft spongy bone that is located between the
two layers of dense cortical bone.
It has a spider web appearance , it’s composed of numerous bony
trabeculae that form a lattice- like network of intercommunicating
spaces filled with marrow spaces

11. Trabecular Pattern in anterior maxilla
The trabeculae is thin
& numerous, forming
a fine, granular,dense
pattern& the marrow
space small and
relatively numerous.

12. Trabecular Pattern in
posterior maxilla
Similar to anterior
maxilla, the marrow
spaces may be
slightly larger.

13. Trabecular Pattern in
anterior mandible
The trabeculae thicker&
fewer than in the
maxilla, with large
marrow spaces.
Coarser pattern with
trabecular plates
oriented more
horizontally

14. Trabecular Pattern in
the posterior mandible
Trabecular plates
oriented more
horizontally.
Marrow space
comparable to ant.
Mand. But larger.

16. Follicle

18. Dental Papilla

19. Anterior Maxillary Projection

20. Nasal fossa(nasal cavity)
A pear-shaped
compartment of bone
superior to maxilla.
Radiographically.
 large radiolucent area
above the maxillary
incisors.

21. Nasal Septum
 a vertical bony wall that
divides the nasal cavity
into RT & LT fossa, it is
formed by two bones and
cartilage.
Radiographically:
Vertical radiopaque partition
divide the nasal cavity.super
imposed over the median
palatal suture

22. Floor of Nasal Cavity
Is a bony wall formed by the
palatal processes of the
maxilla & horizontal portion
of palatine bone,extends
bilaterally away from ANS.
Radiographically:
dense radiopaque band of bone
above the maxillary incisors.

23. Anterior Nasal Spine
Is a sharp projection of
the maxilla located at
the anterior & inferior
portion of the nasal
cavity.
Radiographically:
V-shaped Radiopaque area at
the intersection of the floor of
the nasal cavity & the nasal
septum.

24. Intermaxillary Suture
Median palatal suture.
Joint bet the 2 palatine
processes of the maxilla
Extends from alveolar
crest through ANS,to the
posterior hard palate
Radiographically:
Thin radiolucent line bet the
maxil central incisors, Uniform
width

25. Soft Tissue Outline of Nose
The nose can be
seen as a soft tissue
shadow, usually
radiopaque, along the
root of the maxillary
incisors.

26. Incisive Foramen
Is opening through
which the
nasopalatine nerve &
vessels pass.
Radiographically:
Radiolucent,oval shaped
Variable size and shape.
Variable position, due to
angulation of x-ray beam

27. Nasopalatine Canal
Transmits
nasopalatine nerves
and vessels.
Terminates in
incisive foramen.
Not always seen.

28. Superior Foramina of the
nasopalatine canal

29. Nasolacrimal Canal

30. Inferior nasal Conchae
Concha shell- shaped
thin curved plate of bone
extend from the lateral
wall of the nasal cavity.
Radiographically:
Diffuse radiopaque mass
or projection within the
nasal cavity.

31. Nasal Mucosa

32. Lateral fossa(canine fossa)
Is a smooth
depressed area of the
maxilla bet the canine
& lateral incisor.
Radiographically:
Radiolucency bet canine
and lateral inc.
the appearance varies
depend on the anatomy

33. Maxillary Premolar & Molar projection

34. Inverted “Y” of Ennis
Inverted Y refers to
intersection of nasal
fossa and maxillary
sinus.
Radiographically:
Radiopaque upside-
down “y” above the max
canine

35. Nasolabial Fold/ Cheek Mass

36. Maxillary Sinus
Paired cavities of bone
within the maxilla .
Located above the max
pre-molar & molar
Radiographically:
Radiolucent area
surrounded by radiopaque
line above the apices of max
pre-molar & molar

37. Maxillary sinus-septa

38. Maxillary sinus and Nutrient
canals
Tube like passageways
through the bone that house
BV & nerve to maxillary teeth.
Radiographically:
Narrow radiolucent band
bounded by two thin
radiopaque line representing
the cortical bone

39. Maxillary Sinus
Floor of sinus extends
to alveolar crest due
to missing teeth

42. Floor / Wall of Maxillary Sinus
Wavy outline of the
sinus

43. Maxillary Tuberosity
Is rounded prominence of
bone that extend post to
max 3
rd
molar region.
Radiographically:
Radiopaque bulge distal to
3
rd
molar region

44. Hamulus(hamular process)
Is a small hook-like
projection of bone that
extend from the medial
pterygoid plate
Posterior to max tuberosity
region
Radiographically:
Radiopaque hook-like
projection.
Varies in length, shape &
density

45. Zygomatic process of the maxilla
A bony projection of the
maxilla that articulates
with the zygoma.(dense
bone)
Radiographically:
J or U ahaped radiopacity
superior to max 1
st
molar
region

46. Zygoma(Malar bone)
It is comprised of dense
cortical bone.
Articulation of cheek bone
with the zygomatic process
of maxilla
Radiographically:
Diffuse radiopaque band that
extend posteriorly from the
zygomatic process of maxilla

47. All Those Horizontal Lines!

48. Alveolar Ridge

49. Floor / Wall of Maxillary Sinus

50. Zygomatic Arch (Inf. Border)

51. Zygomatic Process of Maxilla

52. Floor of Nasal Cavity

53. Tuberosity

54. Marked prominence of
bone on the ant ramus of
the mand.
Coronoid Process
Radiographically:
Triangular radiopacity
superimposed over,or
inferior to the max
tuberosity region

55. End of Part I

56. Anterior Mandible

57. Anterior mandible

58. Genial Tubercle
Tiny bumps of bone that serve
as attachment site for
genioglossus and geniohyoid
muscles.
Located on the lingual aspect
of the mand.
Radiographically:
Ring-shaped radiopacity
below the apices of the man
incisors

59. Genial Tubercle

62. Lingual Foramen
Tiny opening or hole in bone
located on the internal surface of
mand,near the midline &
surrounded by genial tubercles
Radiographically:
Small radiolucent dot inf to
the apices of man incisore

63. Nutrient Canals
Tube-like passageway
through bone that house
nerves & blood vessels
Seen in area of thin bone
Radiographically:
Vertical radiolucent lines

65. Mental Ridge
Is a linear prominence of cortical
bone on the external surface of
the ant portion of the man.
It extend from the premolar to the
midline & slop upward
Radiographically:
Thick radiopaque band
Superimpose over the mand
ant teeth.

66. Mental fossa
Scooped-out, depressed area
of bone on the external
surface of the ant man
Radiographically:
Radiolucent area bet the
alveolar ridge and mental
ridge.

67. Mandibular Premolar & Molar projection

68. Mental foramen
Is an opening located on
the ext surface of the
mand in the mandibular
premolar region.
Radiographically:
Small round or void
radiolucency in the apical
area of premolar

69. Posteriorly Positioned Foramen

70. Mandibular Posterior Region

71. Alveolar Ridge

72. External Oblique Ridge
Linear prominence of
bone located on the exter
surface of the body of the
mand
Radiographically:
Radiopaque band extend
downward & forward from the
ant border of the ramus of the
mand,it ends in the mand 3
rd

molar area

73. Mylohyoid Ridge (Internal oblique ridge)
Linear prominence of bone on
the internal surface of the
mand,it extend from the molar
region downward & forward
toward the lower border of the
mand symphysis
Radiographically:
Dense radiopaque band
Superimposed over root of
mand teeth

74. Mandibular Canal
Tube-like passageway through
bone that travels the length of
the mand.
Extend from mand foramen to
mental foramen& house inferior
alveolar nerve and vessels
Radiographically:
Radiolucent band outlined by two
thin radiopaque lines.
Below or superimposed over the
apices of the molar teeth

75. Submandibular Fossa
A scooped-out, depressed
area of bone on the internal
surface of the mand below
mylohyoid ridge
Radiographically:
Radiolucent area in molar
region

76. Inferior Border of Mandible
Dense radiopaque
band of bone

77. Thin inferior border of
mandible
Socket outline

78. The End