Normal Radiographic Anatomical Landmarks

PRESENTATION OF NORMAL ANATOMICAL LANDMARKS ON INTRA ORAL PERIAPICAL RADIOGRAPHS.

ORAL AND MAXILLOFACIAL RADIOLOGY

1. NORMAL RADIOGRAPHIC ANATOMICAL LANDMARKS DR. DIVYA RANA

2. a b c a : enamel B : dentin C : pulp

3. Cervical burnout : Radiographs sometimes show Diffuse radiolucent areas With ill defined borders Present on mesial n distal Aspects of teeth in cervical region These regions appear between The edge of the enamel cap And the crest of the alveolar Ridge. It should not be confused with Root caries.

4. Lamina dura : It is a thin radio-opaque Layer Of dense bone surrounding the Tooth socket. It is thicker than the surrounding Trabecular bone and thickness Increases with increase in amount In the occlusal stress

5. Alveolar crest The gingival margin of the Alveolar process that extends Between the teeth is Apparant on radiographs As radiopaque line called Alveolar crest. It is considered as normal If it is not > than 1.5 mm From cej of adjacent teeth.

6. Periodontal ligament space PDL space is primarily composed of collagen, so appers as radiolucent Space between tooth root and lamina dura .

7. Cancellous bone : it lies between the cortical plates in both the jaws. It is composed of thin radiopaque plates and rods surronding many Small radiolucent marrow spaces.

8. Email Likd × Save Embed Landmarks of maxilla median palatine suture Nasal fossa Nasal septum Anterior nasal spine Incisive foramen Lateral fossa Maxillary sinus Malar bone Maxillary tuberosity Hamular process Nasolacrimal duct

9. Maxillary anterior region Nasal septum Nasal fossa Nasal spine Insicive foramen Nose Median palatine suture

10. A-Nasal septum B-Nasal fossa C-Anterior nasal spine D-Incisive foramen E-Median palatine suture a b c d e

11. Nasal cavities Nasal septum Anterior nasal spine Median palatine suture

12. 1 .Nasal septum (17): appears as a radio-opaque line that separates the two nasal fossa in the midline. 2. Anterior nasal spine (16): appears as a V-shaped radio-opaque structure in the midline above the incisive foramen. 3. Incisive foramen (12): or the anterior palatine fossa , it usually appears as a prominent radiolucent area above or between roots of two central incisors, it usually appears round or oval in shape and doesn’t exceed 6mm in diameter.

13. Palatal view Median palatine suture

14. Median palatine suture Appears as a vertically oriented Radiolucent line in true image projections through the midline. Usually prominent between the two central incisor roots in Young individuals.

15. Palatal view Incisive foramen

16. Red arrow points to periapical lesion periapical cyst

17. Red arrow : mesiodens mesiodens

18. Incisive canal cyst

19. Facial view Nasal septum

20. Facial view Nasal fossa

21. Soft tissues of nose

22. Red arrow : soft tissues of nose Green arrow :lip line

23. Floor of nasal fossa Maxillary sinus Lateral fossa Nose Maxillary canine

24. a: Floor of nasal fossa b: Maxillary sinus c: Lateral fossa a b c

25. Floor of nasal fossa (red arrow) and anterior border of maxillary sinus (blue arrows),forming the inverted (upside down ) Y

26. Lateral fossa : the radiolucency results from a depression Above and posterior to the lateral incisor. To help rule Out a pathology, look for an intact lamina dura Surrounding the adjacent bone.

27. The maxillary sinus surrounds The root of the canine, Which may be misinterpreted As pathology. Black arrows indicate the floor of the nasal fossa ,the max sinus (red arrows) has pneumatized bet the 2 nd PM And 1 st molar.

28. Sinus septum Zygomatic process Maxillary sinus Maxillary premolar region

29. a: Malar process c: Sinus septum d: Maxillary sinus a c d a c d

30. Maxillary sinus zygoma ptrygoid plate Hamular process Coronoid process maxillary tuberosity Maxillary molar region

31. Maxillary sinus : The maxillary sinus with Its thin bony walls, its thin mucosa, and its vast Air space, produce an Extremely dark image Deep to the maxillary Teeth. Its outlines, particularly its Floor, are clearly delineated By delicate radio-opaque lines

32. 1- body of zygoma 6- apices of roots 7 - floor of the sinus 8- septum of the sinus molar region

33. In general ,the floor of the sinus is Approximately coincidental with The location of the apices of the Roots of the upper teeth (bicuspids And first two molars ). But there is often as much as two Or even three mm of maxillary Bone between the root ends and Sinus floor.

34. In other cases the sinus floor dips so deeply between the roots of the Maxillary teeth that the latter appear to project into it for as much as One half of their length

35. Pneumanization :expansion of sinus wall into surrounding bone, usually in an area where teeth have been lost prematurely. It increases with age .

36. a c d e g e g d c a b f f A :max tuberosity e : zygoma (dotted lines) B : coronoid process f : max sinus C : hamular process g :sinus recess D: pterygoid plates Image of the imacted third molar superimposed

37. Malar ( zygomatic ) process. U or j- shaped Radio-opacity, often superimposed over the roots Of the molars, specially when using the bisecting Angle technique. The red arrows define the Lower border of the zygomatic bone.

38. Maxillary tuberosity : the rounded elevation located at the posterior aspect of both sides of the maxilla.

39. Malar bone : or the zygomatic Process. The inferior portion Of the malar bone appears As a radio-opaque, U shaped structure Related to the roots of the first Maxillary molar. It represents the Attachment of the zygomatic bone To the maxilla. Maxillary tuberosity : appears As a radio-opaque structure that Extends distally and upward from Posterior to maxillary sinus. It Represents the end of maxilla .

40. Black arrows : hamular process Purple arrows : pterygoid plates

41. Coronoid process : it is seen as a radio-opaque structure in maxillay molar iopa .

42. Hamular process: It is a bony spine extending from Pterygoid process of the sphenoid Bone. It appears as a radio-opaque Spine that is recorded on radiographs Distal to the tuberosity of maxilla And extends downward. Coronoid process of the mandible: Appears as a triangular radio-opaque structure projected into the same general area of max periapical film projections distal to the maxillary teeth.

43. The zygomatic process (green) is a U shaped rationality. Normally the Zygomatic bone posterior to this is very dense and radio-opaque. In this, however the max sinus has expanded into the zygomatic bone and makes the area more radiolucent (red). The coronoid process (orange), the pterygoid plates (blue) and the max tuberosity (pink) are also identified .

44. Nasolacrimal duct : It is seen in occlusal view of the maxilla as a round radiolucent area superimposed on the posterior region of the hard palate.

45. Landmarks of mandible Lingual foramen Genial tubercles Mental ridge Mental foramen Mental fossa External oblique line Internal oblique line Mylohyoid line Mandibular foramen Inferior alveolar canal Submandibular gland fossa Nutrient canals

46. Mandibular symphysis In a new born infant Symphysis Fracture

47. Mandibular incisor region mental fossa Lingual foramen Genial tubercle Mental ridge

48. a b c d C :mental ridge D: mental fossa A: lingual foramen b: genial tubercles

49. Lingual foramen : radiolucent ‘hole ’ in centre of genial tubercles. Lingual nutrient vessels pass through this foramen .

50. Lingual foramen It is set in the midline deep To the apices of the Anterior teeth. It appears as a small Radiolucent dot at the Symphysis area usually Surrounded by a radio Opaque structure.

51. Genial tubercles : radio-opaque area in the midline surrounding The lingual foramen

52. Genial tubercles : They appear as radio Opaque circle that surrounds the lingual foramen just below the apices of the Of the incisors.

53. mental ridge

54. Mental ridge : it is a bony prominence found on the labial Aspect of the mandible near its inferior border and extended From the premolar region to the symphysis area on wchich It takes an upward turn as it approaches it. It appears as a Radio opaque line below the apices of anterior teeth.

55. mental fossa : this represents the depression on the labial aspect of the mandible overlying the roots of the incisors. The resultant radiolucency may be mistaken for pathology

56. Nutrient canals : The arrows above identify nutrient Canals. They are most often seen in Persons with thin bone and in Those with high blood pressure Or advanced periodontitis . Nutrient canals

57. Mental foramen (3) It appears as a radiolucent, ill defined area between the apices of bicuspids. it represents the anterior Terminates of the mandibular canal.

58. 6- caries 7- prepared cavity 8- enostosis 9 –mental foramen

59. Mandibular premolar region A – mylohyoid ridge B - mandibular canal c – submandibular gland fossa d – mental foramen

60. b - Mandibular canal d -Mental foramen a- Mylohyoid ridge c - Submandibular gland fossa d b a c

61. mental foramen

62. Mandibular molar region A – external oblique ridge B – mylohyoid ridge C – mandibular canal D- submandibular gland fossa

63. A -External oblique ridge c - Mandibular canal B - Mylohyoid ridge D - Submandibular gland fossa a c b d

64. External oblique ridge - a continuation of the anterior border of ramus passing downward and forward on the buccal side of the mandible. It apperas as a radio-opaque line which usually ends anteriorly in the Area of the first molar. The red arrow points to the mylohyoid ridge .

65. The external oblique ridge (red) and the mylohyoid ridge (blue) Usually run parallel to each other , with the external oblique ridge Always being higher on the film .

66. Internal oblique ridge - It appears as a radio opaque Line, descending downwards And forward from coronoid Process, in a horizontal Position, stop at the third Molar area or become cotinuous With the mylohyoid line Its placed below the external Oblique ridge.

67. Mylohyoid ridge (internal oblique) – located on the lingual Surface of the mandible , extending from third molar area to Premolar region

68. Mandibular canal : arises at the mandibular foramen on the Lingual side of the ramus and passes downward and forward, Moving from the lingual side in the third molar region to the buccal Side in the premolar region. It contains the inferior alveolar nerves and vessels.

69. The mandibular canals (red arrows) usually runs very close to the molars Green arrow showing dilaceration of roots. The other film shows impaction at the superior border of the canal .

70. Bifid mandibular canal : cone beam section Cross section

71. Submandibular gland fossa

72. Submandibular gland fossa - It is a depression on the lingual Aspect of the mandible on which Submandibular glands are Present. It appears as a zone of Radiolucency below the Lower molars

73. A – external oblique ridge B – mylohyoid ridge c – mandibular canal D – submandibular gland fossa a b c d

74. THANK YOU PRESENTED BY: DR . DIVYA RANA