Maxillofacial RadiologyDr Rince MohammedJR2 OMFSGovt Medical College Kottayam
Introduction
The anatomy of maxillofacial region is the most complex in the body. Injuries of this region range from isolated injuries to complex facial
injuries involving the entire facial skeleton. Diagnostic imaging has played a central role in providing information
essential in diagnosis and treatment of these injuries.
Common imaging modalities
Plain radiographs (conventional) Computed tomography (CT) CBCT (Cone beam computed tomography) Magnetic resonance imaging (MRI) Ultrasonography Contrast enhanced imaging
(sialography ,arthrography,angiography )
Plain radiographs (conventional)
1-Intra-oral radiograph :
Intra oral Periapical radiographs (IOPA) Bite-wing Occlusal radiograph :
Maxilla (occlusal view )Mandible (occlusal view )
Intra oral Periapical radiographs (IOPA)
Indications
To diagnose periapical pathology To determine root morphology To study eruption of teeth To find out impacted teeth,root stumps,fracture of teeth To evaluate root apex formation
Bite-wing radiograph
Used for• Early recognition of proximal
caries.• Proximal marginal integrity of
restorations and crowns.• Calculus accumulation in the
proximal regions.• To assess alveolar bone height
Occlusal radiographs
INDICATIONS
To locate roots and supernumerary,unerupted, and impacted teeth.
To localize foreign bodies in the jaws and stones in the ducts of salivary glands.
To aid in the examination of patients with trismus. To obtain information about the location, nature, extent, and
displacement of fractures of the mandible and maxilla To determine the medial and lateral extent of pathologies
(e.g., cysts, osteomyelitis, malignancies) and detect disease in the palate or floor of the mouth
Extra oral radiographs
Panoramic radiography (O.P.G) Lateral cephalometric projection True lateral skull P.N.S view P.A skull view P.A mandible Submento vertex Lat oblique Tmj imaging
Orthopantomography
A technique for producing a single tomographic image of the facial structures that includes both the maxillary and mandibular dental arches and their supporting structures.
pantomography is derived from two words – panorama and tomography
Ortho - straight Panoramic - An unobstructed or a complete view of the object in
every direction Tomography – An xray technique for making radiographs of layers of
tissue in depth, without the interference of tissue above and below that level
Principle
As the tubehead rotates around the patient, the x-ray beam passes through different parts of the jaws, producing multiple images that appear as one continuous image on the film (“panoramic view”).
Indications-
Evaluation of- Trauma Location of third molars Extensive dental or osseous disease Known or suspected large lesions Tooth development Retained teeth or root tips TMJ pain Dental anomalies etc.
Ext. Auditory meatus
Mandibular condyle
Articular eminence
Coronoid process
Zygomatic bone
Ptregomaxillary FissureInf. orbital rimFloor of Maxillary sinus
Ant. wall of Maxillary sinusHard palate
Nasal fossa
Inf. Orbital canal and foramen
Zyg. process of Maxilla
Lat. ptreg. plate
Man. fossa
Inf. border of Mandible
C- Spine
Mental foramen Hyoid bone Inf. Alveolar canalExt. oblique ridge
Hard Tissue
Advantages…
Broad anatomic coverage Low patient radiation dose Convenience of examination Used in patients unable to open mouth
Disadvantages
Does not show fine anatomic details Magnification Distortion Overlapped image of teeth Expensive
Lateral cephalometric projection
USES
• It helps in the classification of skeletal and dental abnormalities.
• Study of craniofacial growth
• Recognizing and evaluating changes brought about by orthodontic treatment
• Cephalometrics helps in predicting the growth related changes and changes associated with surgical treatment.
• Pathologic changes in the skull , jaws or cranial base can be observed.
Porion (P):most superior point of EAM
Sella(S): Centre of hypophyseal fossa
Nasion(N):Frontonasal suture
Orbitale(O): Most inferior point of IO rim
N S O
P
Lateral cephalogram-land marks
PT point: most posterior point of PM fissure
Basion(Ba):most antr point of F magnum
PNS: tip of Postr nasal spine
ANS: tip of Antr nasal spine
PTPNSBa
Lateral cephalogram
Point A: deepest point of antr border of maxillary alveolar ridge concavity
Point B: deepest point of antr border of mandibular alveolar ridge concavity
Pogonion(Po): most anterior point of symphysis
A
BPogonion
Lateral cephalogram
Gnathion(Gn): midpoint of symphysis outline between Po & M
Menton(M): Most inferior point of symphysis
Gonion(G): most convex point along the infr border of mand ramusGn
MG
Lateral cephalogram
TRACING
Cephalometric analysis
The major use of radiographic cephalometry is in characterizing the patient’s dental and skeletal relationships.
William. B. Downs developed the first cephalometric analysis. This was later followed by other analyses by Steiner (1952), Tweed
(1953), Ricketts (1958), Sassouni (1969), etc
True lateral skull
To survey skull and facial bone for trauma or pathology.Nasopharangeal soft tissue, paranasal sinus and hard
palate.Condition affecting sella turcica, such as tumour of pitutary
gland in acromegaly.
Indications
Submandibular sialolith
35
05/03/2023
PA WATERS (P.N.S),(0.M)PROJECTION
Occipito Mental 30° (OM30) View Standard occipitomental (0° OM)
39INDICATIONS
Fractures of the cranium and the cranial base Middle third facial fractures, to show possible downward and
backward displacement of the maxilla Investigation of the frontal, sphenoidal and maxillary sinuses Conditions affecting the skull vault,
Paget’s disease Multiple myeloma Hyperparathyroidism
Conditions affecting the sella turcica, Tumor of pituitary gland in acromegaly
Posteroanterior skull (PA) projection:
Asymmetry
This projection shows the skull vault, primarily the frontal bones and the jaws.
The beam passes through the skull in a posterior to anterior direction.
Purpose: Asymmetry , Developmental abnormalities ,fracture of the skull vault.
Conditions affecting the cranium, particularly:Paget's diseaseMultiple myelomaHyperparathyroidism
Postero-anterior of the jaws (PA jaws/PA mandible)
Indications Fractures of the mandible lesions such as cyst or tumor in post 1/3 of
body & in ramus of mandible. condylar hypoplasia or hyperplasia
Posteroanterior radiographic view of a fracture of the left body and angle.
• The PA view is used to evaluate the entire mandible. However, the symphysis is often obscured by the cervical spine, and the condyles can be superimposed over the mastoid process and occipital bone.
• A Waters view or a basal view should be obtained to better evaluate the symphysis to negate the overlap of the cervical spin.
44 Submentovertex (base) projection
45 indications
Help to s tudy dest ruct ive les ion affect ing the pa late , pterygo id reg ion or base o f the sku l l , spheno ida l s inus .
Fractures o f zygomat ic arches ( JUG HANDLE) .
Lateral oblique
Left angle fracture on a left oblique radiographic image
47
Lateral Oblique Views - Largely replaced by panoramic views
Indications: Impacted third molars fractures of the ramus, body,condyle coronoid of the mandible.
48
49 Transcranial View
50
Indications• Arthritic changes on the articular surface.• To evaluate the joint’s bony relationship.
• Closed view- size of joint space, position of head of condyle, shape & condition of glenoid fossa & articular eminence.
• Open view- range & type of movement Comparison of both sides
Disadvantages :Superimposition of ipsilateral petrous ridge over the condylar neck
51
Transpharyngeal view
52 Indications
• Fracture of condylar head and neck of the mandible
53 Transorbital /ZIMMER view
54 Indications
The anterior view of the temporomandibular joint Medial displacement of fractured condyle Fracture of neck of condyle. There is minimum superimposition.
55
Reverse-towne projection(open mouth)
56
INDICATIONS:
• Suspected fracture of the condylar neck.
• Intracapsular fracture of the TMJ
• Shows posterolateral wall of maxillary sinus
57 Drawbacks of extra oral techniques
Magnification occurs due to the greater object to film distance used.
Details are not well defined.Contrast is reduced as the secondary
radiation produced by the soft tissues is more.
It is a 2- D image of 3- D structure.
CONCLUSION Thorough knowledge of the indications
of various extra oral techniques allows accurate and timely diagnosis of various maxillofacial pathologies. Further, we can arrive at a diagnosis with minimum number of x-rays there by reducing patient exposure to radiation.
DR ANKIT GOEL, SUBHARTI.