Radiographic Features of Head and Neck Trauma

1. TRAUMA
Dr. Hadi Munib
Oral and Maxillofacial Surgery Resident

2. OUTLINE
• Introduction
• Applied Radiology
• Traumatic Injuries to the teeth
• Traumatic Injuries to the Facial Bones
• Monitoring of Healing for Fractures

3. INTRODUCTION
• Radiologic examination is essential for evaluating trauma to the
teeth and jaws.
• The presence, location, and orientation of fracture planes and
fragments can be determined, and the involvement of nearby vital
anatomic structures can be assessed.
• Foreign objects that have become embedded within the soft
tissues as a result of trauma can be detected.
• Follow-up images are useful in evaluating the extent of healing
after an injury and long-term changes resulting from the trauma.

4. APPLIED RADIOLOGY
• The ideal imaging study may be difficult to perform after trauma
because of the nature of the injury and patient discomfort.
• Prescription of the appropriate images should be ordered only
after a careful clinical examination, in some cases this is not
always possible.
• If plane radiography is to be used, multiple images should be
made at differing angles, including at least two views made at
right angles to each other.
• In many centers, computed tomographic imaging (CT) has
replaced plane radiography as the standard imaging modality.

5. APPLIED RADIOLOGY
• Intraoral
• Panoramic
• Lateral oblique projections of the mandible for dento-alveolar
and mandibular injuries
• Posteroanterior
• Waters
• Submentovertex
• Towne
• Lateral projections for midface and skull injuries.

6. APPLIED RADIOLOGY
• Panoramic image may be useful for localizing the area of an injury, it may not have
the image resolution to reveal injuries involving the anterior mandible or maxillae
or the teeth.
• Dentoalveolar trauma always requires intraoral images to obtain adequate
anatomic detail.
• A minimum of two intraoral periapical images should be made at different
horizontal x-ray beam angulations.
• Occlusal views may be particularly useful depending on the severity of the trauma
and the ability of the patient to open the mouth.
• If a tooth or a large fragment of a tooth is missing, a chest or abdominal image may
be considered to locate the tooth.
• Placing an intraoral film or receptor in the mouth adjacent to the traumatized soft
tissue and then exposing it.
• If the laceration is in the tongue, a standard mandibular occlusal image may be
exposed or the tongue can be protruded and then imaged.

9. APPLIED RADIOLOGY – MANDIBULAR FRACTURES
• Panoramic image may be a good initial image to make for assessing
mandibular fractures, the intraoral cross-sectional occlusal view of the
mandible may provide important information about body or alveolar
process fractures in the tooth-supporting areas.
• What if there’s no Panoramic X-Ray  Lateral oblique views of the
mandible should be made.
• The open mouth Towne view may be particularly useful in cases of
suspected trauma to the mandibular condylar head and neck areas.
• These views are important to supplement lateral views of the
temporomandibular joint, especially in cases of nondisplaced greenstick
fractures of the condylar neck.
• For suspected multiple and complex fractures of the mandible, CT is the
imaging modality of choice.
• Magnetic resonance imaging may be useful to assess soft tissue injury to
the temporomandibular joint capsule or articular disk.

10. APPLIED RADIOLOGY
• Although some centers continue to rely on plane radiography for
suspected localized trauma to the maxillofacial skeleton.
• CT is the imaging method of choice for more widespread complex
fractures.
• RADIOGRAPHIC SIGNS OF FRACTURE
• Fractures are often erroneously referred to as “lines” in spite of their
three-dimensional nature.
• Fractures represent planes of cleavage through a tooth or bone, and
these planes extend deep into the tissues.
• Fractures may be missed if the plane of the fracture is not aligned with
the direction of the incident x-ray beam on a single-plane image.

11. APPLIED RADIOLOGY
• General signs that may indicate the presence of a fracture of a
tooth or bone:
1. The presence of one or two usually sharply defined radiolucent
lines within the anatomic boundaries of a structure.
2. A change in the normal anatomic outline or shape of the
structure.
3. A loss of continuity of an outer border.
4. An increase of the Radiopacity of the structure

12. TRAUMATIC INJURIES TO TEETH

13. CONCUSSION
• A crush injury to the vascular structures at the tooth apex and the periodontal
ligament resulting in inflammatory edema.
• No displacement and only minimal loosening of the tooth occurs.
• The injury may result in mild avulsion of the tooth from its socket, causing its occlusal
surface to make premature contact with an opposing tooth during mandibular
closing.
• The patient usually complains that the traumatized tooth is tender to touch, which
can be confirmed by gentle horizontal or vertical percussion of the tooth.
• The tooth may also be sensitive to biting forces, although patients will usually try to
modify their occlusion to avoid contacting the traumatized tooth.
• Radiographic Features
• The radiographic appearance of a dental concussion may be subtle.
• No radiographic changes may be found or localized widening of the apical periodontal
ligament space may be seen

14. CONCUSSION
• Reduction in the size of the pulp chamber and root canals may
develop in the months and years after traumatic injury to the teeth
• This may be particularly evident in teeth that are still developing.
• If the pulp becomes necrotic, there may be no further deposition of
(secondary) dentin as the odontoblasts and the pulpal stem cell
populations die. The development of rarefying osteitis may ensue, and
in rare cases, internal root resorption
• Management; conservative and slight adjustment of the opposing
teeth (if necessary) or the application of a flexible splint.
• Periodic monitoring in the first year with repeated vitality testing and
radiographs are indicated.

16. LUXATION
• Dislocation of the tooth from its socket after severing of the periodontal
attachment.
• Teeth are both abnormally mobile and displaced.
• Subluxation of the tooth denotes an injury to the supporting structures of
the tooth that results in abnormal loosening of the tooth without frank
dislocation.
• Depending on their magnitude and direction, traumatic forces can cause
• Intrusive luxation (into the alveolar process)
• Extrusive luxation (movement of tooth out of its socket).
• Lateral luxation (movement of a tooth in a direction other than both).
• In intrusive and lateral luxation, comminution or crushing of the alveolar
process may accompany tooth dislocation.

17. LUXATION
• Temporary or permanent changes to the dental pulp  The
movement of the apex and disruption of the circulation
• If the pulp survives the traumatic incident, the rate of dentin
formation may accelerate and continue until it obliterates the
pulp chamber and root canal.
• This may take place in permanent and deciduous teeth.
• Subluxated teeth are in their normal location but are abnormally
mobile.
• Clinical crowns of intruded teeth may appear reduced in height

18. LUXATION
• Usually two or more teeth are involved in luxation injuries.
• The teeth most frequently affected are the deciduous and permanent
maxillary incisors.
• The mandibular teeth are seldom affected
• Radiographic examinations of luxated teeth may demonstrate the extent of
injury to the root, periodontal ligament, and alveolar process.
• A radiograph made at the time of injury serves as a valuable reference point
for comparison with subsequent radiographs.
• The minor damage associated with subluxation may be subtle and limited
to elevation of the tooth from its socket.
• Widening of the apical portion of the periodontal ligament space.
• Elevation of the tooth may not be radiographically apparent.

19. LUXATION
• Intrusion may result in partial or total obliteration of the apical
periodontal ligament space.
• Multiple radiographic projections may be necessary to show the
direction of tooth displacement and the relationship of the
displaced tooth to adjacent teeth and the outer cortex of bone.
• A tooth that has been extruded may demonstrate varying degrees
of apical widening of the periodontal ligament space, depending on
the magnitude of the extrusive force.
• Management; Digital Pressure, Splint, Extraction?

20. INTRUSION VS. EXTRUSION

21. AVULSION
• Complete displacement of a tooth from the alveolar process.
• Direct trauma when the force is applied directly to the tooth
• Indirect trauma when indirect force is applied to teeth as a result of the jaws
striking together.
• Avulsion occurs in about 15% of traumatic injuries
• Fights being responsible for the avulsion of most permanent teeth and
accidental falls accounting for the traumatic loss of most deciduous teeth.
• Maxillary central incisors are the most commonly avulsed teeth from both
dentitions.
• Most often only a single tooth is lost.
• Typically this injury occurs in a relatively young age group when the
permanent central incisors are just erupting.
• Fractures of the alveolar process and lip lacerations may be seen with an
avulsed tooth.

22. AVULSION
• In a recent avulsion, the lamina dura of the empty socket is
apparent and usually persists for several months.
• The missing tooth may be displaced into the adjacent soft tissue.
• A soft tissue image of the lacerated lip or tongue should be made.
• In some instances new bone within the healing socket may be
very dense and simulate a retained root tip
• Management; Re-implantation, HBSS, Saliva, Milk as storage
mediums

24. DENTAL CROWNS FRACTURES
• Fractures of the dental crown account for about 25% of traumatic
injuries to the permanent teeth
• 40% of injuries to the deciduous teeth.
• The most common event responsible for the fracture of permanent
teeth is a fall, followed by accidents involving vehicles and blows from
foreign objects striking the teeth.
• Fractures involving only the crown normally fall into three categories:
• 1. Fractures that involve only the enamel without the loss of enamel
substance (infraction of the crown or crack)
• 2. Fractures that involve enamel or enamel and dentin with loss of tooth
substance but without pulpal involvement (uncomplicated fracture)
• 3. Fractures that pass through enamel, dentin, and pulp with loss of
tooth substance and exposure of the pulp (complicated fracture)

25. DENTAL CROWNS FRACTURES
• Fractures of the dental crowns most frequently involve anterior
teeth.
• Infractions or cracks in the enamel are quite common but
frequently are not readily detectable.
• Illuminating crowns with indirect light causes cracks to appear
distinctly in the enamel.
• Histologic studies show that they pass through the enamel but not
into the dentin.
• The pattern and distribution of these cracks are unpredictable
and apparently relate to the trauma.

26. DENTAL CROWNS FRACTURES
• Uncomplicated crown fractures that do not involve dentin
usually occur at the mesio-incisal or disto-incisal corners of the
maxillary central incisor.
• Loss of the central portion of the incisal edge may also occur.
• Fractures that involve dentin can be recognized by the contrast
in color.
• The exposed dentin is usually sensitive to chemical, thermal, and
mechanical stimulation.
• In deep fractures, the pink blush of the pulp may be appreciated
through the thin remaining dentin wall.

27. DENTAL CROWNS FRACTURES
• Uncomplicated fractures that involve both the enamel and the
dentin of permanent teeth are more common than complicated
fractures are.
• In contrast, the incidence of complicated and uncomplicated
fractures is about equal in the deciduous teeth.
• Complicated crown fractures are distinguishable by bleeding from
the exposed pulp or by droplets of blood forming from pinpoint
exposures.
• The pulp is visible and may extrude from the open pulp chamber if
the fracture is old.
• The exposed pulp is sensitive to most forms of stimulation.

28. DENTAL CROWNS FRACTURES
• Radiographic Features
• Information regarding the location and extent of the fracture and the
relationship of the fracture plane and fragment to the pulp chamber.
• The stage of root development of the involved tooth can be assessed with
radiography.
• This initial image also provides a means of comparison for follow-up
examinations of the involved teeth.
• The prognosis for teeth with fractures limited to the enamel is quite good
• Pulpal necrosis develops in fewer than 2% of such cases.
• If a fracture involves both dentin and enamel, the frequency of pulpal necrosis
is about 3%.
• Management; Smoothening, Bonding Agent, Composite Restoration, RCT
or Extraction

30. DENTAL ROOT FRACTURES
• Uncommon and account for fewer than 7% of traumatic injuries to permanent
teeth
• About half that many in deciduous teeth.
• The deciduous teeth are less firmly anchored in the alveolar process.
• Most root fractures occur in maxillary central incisors.
• The coronal fragments are usually displaced lingually and slightly extruded.
• The closer the fracture plane is located to the apex, the more stable the tooth is.
• When testing the mobility of a traumatized tooth, place a finger over the
alveolar process, if movement of only the crown is detected, a root fracture is
likely.
• This is most often observed in the anterior region of the mandible where root
fractures are infrequent.
• Root fracture is usually associated with temporary loss of sensitivity, the
sensitivity of most teeth returns to normal within about 6 months.

31. DENTAL ROOT FRACTURES
• Radiographic Features
• May occur at any level and involve one or all the roots of
multirooted teeth.
• Most of the fractures confined to the root occur in the middle
third of the root.
• The ability of an image to reveal the presence of a root fracture
depends on the relative angulation of the incident x-ray beam to
the fracture plane and the degree of distraction of the fragments.
• Longitudinal root fractures are relatively uncommon but are
most likely in teeth with posts that have been subjected to
trauma.

32. DENTAL ROOT FRACTURES
• Differential Diagnosis
• The superimposition of soft tissue structures such as the lip, ala of
the nose, or nasolabial fold over the image of a root may suggest a
root fracture; the soft tissue image of the lip line usually extends
beyond the tooth margins.
• Pulpal Necrosis happens in around 20 – 24% of Root Fractured
Teeth
• Fractures in the middle or apical third of the root of
permanent teeth can be manually reduced to the proper
position and immobilized.

35. VERTICAL ROOT FRACTURES
• Fracture planes that run lengthwise from the crown toward the apex of
the tooth.
• Usually both sides of a root are involved.
• The crack is usually oriented in the facial lingual plane in both anterior
and posterior teeth.
• These fractures usually occur in the posterior teeth in adults, especially
in mandibular molars.
• They are usually iatrogenic, after insertion of retention screws or pins
into teeth.
• Uncrowned posterior teeth that have been treated endodontically are
most at risk.
• Large occlusal forces are another etiology for vertical root fracture,
particularly in restored teeth.

36. VERTICAL ROOT FRACTURES
• Persistent low-level dull pain, often of long duration, the so-called cracked
tooth syndrome.
• This pain is elicited by applying pressure to the involved tooth.
• Rarefying osteitis or a history of repeated failed endodontic therapy.
• Definitive diagnosis can be made only by inspection after surgical exposure.
• If the central ray of the x-ray beam lies along the plane of the fracture, the
fracture may be visible as a radiolucent line on the image.
• Radiography is not useful in their early stages.
• Later, if rarefying osteitis develops, there will be evidence of bone loss.
• The widening of the periodontal ligament space and this bone loss may not be
centered at the apex but often positioned more coronally toward the alveolar
crest.

37. VERTICAL ROOT FRACTURES
• Single-rooted teeth with vertical root fractures must be
extracted.
• Multirooted teeth may be hemisected and the intact remaining
half of the tooth restored with endodontic therapy and a crown

39. COMBINATION OF CROWN/ROOT FRACTURES
• Involve both the crown and root(s).
• Crown/root fractures usually involve the pulp.
• About twice as many affect the permanent as the deciduous teeth.
• Most fractures of the anterior teeth are the result of direct
trauma.
• Many posterior teeth are predisposed to such fractures by large
restorations or extensive caries.
• The plane of a typical crown/root fracture of an anterior tooth
extends obliquely from the labial surface near the gingival third of
the crown to a position apical to the gingival attachment on the
lingual surface

40. COMBINATION OF CROWN/ROOT FRACTURES
• Displacement of the fragments is usually minimal.
• Crown/root fractures occasionally present with bleeding from the pulp.
• These teeth are sensitive to occlusal forces that may cause separation of
the fragments,
• Usual complaint of pain during mastication.
• These fractures are often not visible on the radiographic image because
the x-ray beam is rarely aligned with the plane of the fracture.
• Vertical crown/root fractures that are oriented in a mainly tangential
orientation relative to the direction of the x-ray beam are readily
apparent on the image. [Not common]

41. COMBINATION OF CROWN/ROOT FRACTURES
• Management
• If the coronal fragment includes as much as 3 to 4 mm of clinical
root, removal of the residual root is recommended.
• If the crown/root fracture is vertically oriented, prognosis is poor
regardless of treatment.
• If the pulp is not exposed and the fracture does not extend more
than 3 to 4 mm below the epithelial attachment, conservative
treatment is likely to be successful.

42. TRAUMATIC INJURIES TO FACIAL
BONES

43. INTRODUCTION
• Facial fractures most frequently affect the zygomatic bones or
mandible and the maxillae.
• Radiography plays a crucial role in the diagnosis and management of
traumatic injuries to these and the other facial bones.
• Superficial signs of injury such as soft tissue swelling, hematoma
formation, or hemorrhage from a laceration or abrasion
• Localized injuries may be investigated with plane radiography.
• Two views of the injured site at right angles to one another to assess
the presence, location, extent, and displacement of a fracture.
• CT is the imaging modality of choice.

44. MANDIBULAR FRACTURES
• The most common mandibular fracture sites are the condyle, body, and
angle, followed less frequently by the Parasymphyseal region, ramus,
coronoid process, and alveolar process.
• Trauma to the mandible is often associated with other injuries, most
commonly concussion and other fractures, usually of the maxillae,
zygomatic bones, and cranial vault.
• Most common causes of mandibular fractures are assault, falls, and
sports injuries.
• About half of all mandibular fractures occur in individuals between 16
and 35 years old.
• Injuries in males are reportedly three times more common than in
females.
• Weekends

45. MANDIBULAR BODY FRACTURES
• The mandible is the most commonly fractured facial bone.
• A fracture of the mandibular body on one side is frequently
accompanied by a fracture of the condylar neck on the opposite
side.
• Trauma to the anterior mandible may result in unilateral or
bilateral fractures of the condylar necks.
• When a localized heavy force is directed posteriorly to the
mandible, there may be fractures of the angle, ramus, or even the
coronoid process.
• In children, fractures usually occur in the anterior region

46. MANDIBULAR BODY FRACTURES
• Classified as being either favorable or unfavorable, depending on
the orientation of the fracture plane.
• Unfavorable fractures are those in which the action of muscles
attached to the mandibular fragments displace the fragments
away from one another.
• If a fracture plane in the body of the mandible slants obliquely
posteriorly and inferiorly from the base of the anterior border of
the ramus, the masseter and medial pterygoid muscles may
displace the ramal fragment superiorly and away
• In favorable fractures, the muscle action tends to reduce the
fracture.

47. MANDIBULAR BODY FRACTURES
• Clinical Features
• Frequently the patient has swelling and a deformity that is
accentuated when the patient opens the mouth.
• A discrepancy is often present in the occlusal plane, and
manipulation may produce crepitus or abnormal mobility.
• Intraoral examination may reveal ecchymosis in the floor of the
mouth.
• In the case of bilateral fractures to the mandible, a risk exists that
the digastric, mylohyoid, and omohyoid muscles will displace the
anterior mandibular fragment posteriorly and inferiorly, causing
impingement on the airway.

48. MANDIBULAR BODY FRACTURES
• Intraoral, Occlusal, Panoramic, Postero-Anterior View and CT scan.
• The margins of fracture planes usually appear as sharply defined
radiolucent lines of separation that are confined to the structure of
the mandible.
• Displacement of the fragments results in a cortical discontinuity or
“step” or an irregularity in the occlusal plane.
• Occasionally, the margins of the fracture overlap each other,
resulting in an area of increased Radiopacity at the fracture site.
• Nondisplaced mandibular fractures may involve one or both buccal
and lingual cortical plates

49. MANDIBULAR BODY FRACTURES
• An incomplete fracture involving only one cortical plate is often
called a greenstick fracture; usually occur in children.
• An oblique fracture that involves both cortical plates may cause
some diagnostic difficulties if the fracture lines in the buccal and
lingual plates are not superimposed.
• Differential Diagnosis
• The superimposition of soft tissue images.
• A narrow air space between the dorsal surface of the tongue
and the soft palate superimposed across the angle of the
mandible in a panoramic X-ray.
• Management; Antibiotics and Reduction

53. MANDIBULAR CONDYLE FRACTURES
• Divided into condylar neck fractures and condylar head fractures.
• Condylar neck fractures are more common and are located below
the condylar head.
• Condylar neck fracture  the head is usually displaced
medially, inferiorly, and anteriorly; contraction of the lateral
pterygoid muscle.
• Fractures of the condylar head may result in a vertical cleft
dividing the condylar head fragments or may produce multiple
fragments in a compression-like injury.
• Almost half the patients with condylar fractures also have
fractures in the mandibular body.

54. MANDIBULAR CONDYLE FRACTURES
• The clinical symptoms are not always apparent.
• The preauricular area must be carefully examined and palpated.
• The patient may have pain on opening or closing the mouth or
trismus from local swelling.
• An anterior open bite may be present with only distal molar contacts
and there may be deviation of the mandible on opening.
• A significant feature may be the inability of the patient to protrude
the mandible because the lateral pterygoid muscle is attached to the
condyle.
• Nondisplaced fractures of the condylar process may be difficult to
detect on plain radiographic or panoramic images.

55. MANDIBULAR CONDYLE FRACTURES
• CT is the imaging modality of choice
• In children younger than 12 years, most fractured condyles show a
radiographic return to normal morphology after healing, whereas in
teenagers the remodeling is less complete.
• The extent of remodeling is also greater with fractures of the condylar
head than with condylar neck fractures with displacement of the
condylar head.
• The most common deformities are medial inclination of the condyle,
abnormal shape of the condyle, shortening of the neck, erosion, and
flattening.
• Early condylar fractures commonly result in hypoplasia of the
ipsilateral side of the mandible.

59. FRACTURES OF THE ALVEOLAR PROCESS
• Simple fractures of the alveolar process may involve the buccal or
lingual cortical plates of the alveolar processes of the maxillae or
mandible.
• Commonly these fractures are associated with traumatic injuries to
teeth that are luxated with or without dislocation.
• Several teeth are usually affected, and the fracture plane is most often
horizontally oriented.
• Some fractures extend through the entire alveolar process and the
fracture plane may be located apical to the teeth or involve the tooth
socket.
• These are also commonly associated with dental injuries and extrusive
luxations with or without root fractures.

60. FRACTURES OF THE ALVEOLAR PROCESS
• A common location of alveolar fractures is the anterior maxilla.
• Simple alveolar fractures are relatively rare in the posterior segments of the
arches.
• In this location, fracture of the buccal plate usually occurs during removal of a
maxillary posterior tooth.
• Fractures of the entire alveolar process occur in the anterior and premolar
regions and in an older age group.
• Marked malocclusion with displacement and mobility of the fragment, and
when the practitioner tests the mobility of a single tooth, the entire fragment
of bone moves.
• The teeth in the fragment will have a recognizable dull sound when percussed
and the attached gingiva may have lacerations.
• The detached bone may include the floor of the maxillary sinus, in which case
bleeding from the nose on the involved side may occur as well as ecchymosis
of the buccal vestibule.

61. FRACTURES OF THE ALVEOLAR PROCESS
• Radiographic Features
• Periapical radiographs will often not reveal fractures of a single
cortical wall of the alveolar process.
• A fracture of the anterior labial cortical plate may be apparent on an
occlusal radiograph or on a lateral Extraoral image of the mandible if
bone displacement happened.
• Fractures of both cortical plates of the alveolar process are usually
apparent
• The closer the fracture is to the alveolar crest, the greater the
possibility that root fractures are present.
• It may be difficult to differentiate a root fracture from an overlapping
fracture line of the alveolar bone

62. FRACTURES OF THE ALVEOLAR PROCESS
• Management
• Repositioning the displaced teeth and associated bone fragments
with digital pressure.
• Gingival lacerations are sutured.
• Teeth that have lost their vascular supply may eventually require
endodontic treatment.
• A soft diet for 10 to 14 days is recommended.
• Antibiotic coverage is provided because of communication with
tooth sockets.

64. MIDFACIAL FRACTURES

65. ORBITAL BLOW-OUT FRACTURES
• Generated as a result of a direct blow to the orbit by an object that is
too large to enter the orbital cavity.
• One or more of the walls of the orbit are damaged, but the orbital rim
remains intact.
• The most common fractures involve the medial wall of the orbit formed
by the lamina papyracea of the ethmoid bone and the floor of the orbit
that separates this space from the maxillary sinus.
• Periorbital edema is a common feature as is enophthalmos.
• Eye movements may be restricted if one or more of the periorbital
muscles becomes entrapped in the bony defect created by the fracture.
• If the ethmoid air cells are involved, there may be epistaxis.

66. ORBITAL BLOW-OUT FRACTURES
• Radiographic Features
• The Waters view or CT may demonstrate a discontinuity of the
lamina papyracea in a medial wall blow-out fracture.
• The accumulation of soft tissue in the roof of the maxillary sinus in
an orbital floor blow-out.
• Coronal CT may show the classic “trap door” appearance of the
displaced orbital floor to best advantage.
• Soft tissue CT images will show soft tissue densities or air-fluid
levels in the adjacent ethmoid air cells or maxillary sinus or
herniation of periorbital fat and entrapment of periorbital muscle
through the bony defect in the orbital floor.
• Management; Surgical Repair

69. ZYGOMATIC FRACTURES
• Unilateral fractures involving the zygomatic bone may include tripod
fractures.
• In which the zygomatic bone and adjacent areas of the maxillary,
frontal, sphenoid, and temporal bones may be involved, or
• Zygomatic arch fractures, in which the zygomatic process of the
temporal bone is fractured.
• Bilateral zygomatic fractures can occur in association with Le Fort
type II and III fractures
• Injuries to the zygomatic bone or arch usually result from a forceful
blow to the cheek or side of the face.
• Although zygomatic bone injuries may displace the fragment(s)
medially, support by the adjacent temporalis and masseter muscles
may limit displacement.

70. ZYGOMATIC FRACTURES
• Flattening of the upper cheek with tenderness and dimpling of the skin
over the side of the face may occur.
• Some clinical characteristics of zygomatic fractures may not be
apparent much longer than an hour after trauma because they may be
masked by edema.
• Periorbital ecchymosis and hemorrhage into the sclera (near the outer
canthus) occur.
• Unilateral epistaxis (for a short time after the accident), anesthesia or
paresthesia of the cheek, and compromised eye movements.
• The presence of diplopia suggests a significant injury to the floor of the
orbit.
• Mandibular movement may be limited if the displaced zygomatic bone
impinges on the coronoid process.

71. ZYGOMATIC FRACTURES
• The radiographic examination may provide the only means of
determining the presence and extent of the injury.
• The occipitomental (Waters) view provides a good image of the
zygomatic bone and midface.
• An underexposed Submentovertex projection (the so-called jug-handle
view) provides a good view of the zygomatic arch and can often show
the V-shaped deformity of the zygomatic process of the temporal bone.
• CT is the imaging modality of choice for these fractures
• The zygomatic arch may fracture at its weakest point, about 1 cm
posterior to the zygomaticotemporal suture.
• Fractures do not usually occur through the zygomatico-maxillary
suture.
• Management; No treatment; Reduction

73. LE FORT FRACTURES

74. INTRODUCTION
• All Le Fort fractures include fractures of one of the pterygoid plates of
the sphenoid bone
• May be bilateral, they are most often unilateral.
• The radiographic interpretation of fractures of the midface is difficult
because of the complex anatomy in this region and the multiple
superimpositions of structures.
• CT is the diagnostic imaging method of choice for complex facial
fractures; multiple image slices in orthogonal planes through the face,
allowing for the display of osseous structures without the
complication of overlapping anatomy that is problematic with plane
radiography.
• CT also provides suitable image detail to detect secondary changes

75. LE FORT I (HORIZONTAL FRACTURES)
• Relatively horizontal fracture in the body of the maxilla that results in
detachment of the alveolar process and adjacent bone of the maxilla
from the middle face.
• The fracture plane passes superior to the roots of the teeth and nasal
floor and posteriorly through the base of the maxillary sinus and the
tuberosity to the pterygoid processes.
• In the unilateral fracture, an auxiliary fracture exists in the midline of
the palate.
• The unilateral fracture must be distinguished from a fracture within
the alveolar process that does not extend to the midline or involve the
pterygoid plates posteriorly.
• Fractures of the mandible (54%) and zygomatic bone (23%) may also
be found in these patients.

76. LE FORT II (HORIZONTAL FRACTURES)
• If the fragment is not distally impacted, it can be manipulated by holding
onto the teeth.
• If the fracture line is at a high level, the fragment may include the pterygoid
muscle attachments, which pull the fragment posteriorly and inferiorly.
• The posterior maxillary teeth contact the mandibular teeth first, resulting in
an anterior open bite, retruded chin, and long face.
• If the fracture is at a low level, no displacement may occur.
• Swelling and bruising about the eyes, pain over the nose and face, deformity
of the nose, and flattening of the middle of the face.
• Epistaxis is inevitable, and occasionally double vision and varying degrees of
paresthesia over the distribution of the infraorbital nerve may occur.
• Manipulation may reveal a mobile maxilla and crepitation.

77. LE FORT I (HORIZONTAL FRACTURES)
• Radiographic Features
• CT imaging will reveal an air-fluid level or radiopacification in the maxillary
sinus.
• Coronal images may reveal the plane of the fracture extending posteriorly
through the maxilla, whereas coronal or axial images together may reveal
involvement of the pterygoid plates posteriorly.
• Three-dimensional reconstructions of the CT data set may show the plane of
the fracture to greatest advantage
• Management
• If the fracture is not displaced and is at a relatively low level in the maxilla, it
can be treated by intermaxillary fixation.
• Those that are high, with the fragment displaced posteriorly or with
pronounced separation, require craniomaxillary fixation in addition to
intermaxillary fixation

81. LE FORT II (PYRAMIDAL FRACTURES)
• Pyramidal shape on posteroanterior skull images.
• It results from a violent force applied posteriorly and superiorly
through the base of the nose.
• This force separates the maxilla from the base of the skull.
• The fracture plane extends from the bridge of the nose inferiorly,
laterally, and posteriorly through the nasal and lacrimal bones,
the orbital floor and inferior rim obliquely, and inferiorly across
the maxilla and posteriorly to the pterygoid processes.
• The frontal and ethmoid sinuses are involved in about 10% of
cases, especially in severe comminuted fractures.

82. LE FORT II (PYRAMIDAL FRACTURES)
• Clinical Features
• Le Fort II injury results in massive edema and marked swelling of the middle third of the
face.
• Typically, ecchymosis develops around the eyes within minutes of the injury.
• The edema is likely to be so severe that it is impossible to see the globes.
• The conjunctivas over the inner quadrants of the eyes are bloodshot, and if the zygomatic
bones are involved, this ecchymosis extends to the outer quadrant.
• The broken nose is displaced because the face has fallen, and the nose and face are
lengthened.
• An anterior open bite occurs.
• Epistaxis is inevitable, and cerebrospinal fluid rhinorrhea may also result.
• By applying pressure between the bridge of the nose and the palate, the “pyramid” of
bone can be moved.
• Double vision and variable degrees of paresthesia over the distribution of the infraorbital
nerve.

83. LE FORT II (PYRAMIDAL FRACTURES)
• The radiographic examination reveals fractures of the nasal bone, frontal
process of the maxilla, infraorbital rim, and orbital floor.
• More inferiorly and posteriorly, there would be involvement of the
zygomatic bone or zygomatic process of the maxilla, separation of the
zygomatico-maxillary suture, and fracture of the lateral wall of the
maxillary sinus and the pterygoid plates.
• Involvement of the ethmoid air cells, and frontal and maxillary sinuses,
would result in thickening of the sinus
• Management; reduction of the displaced maxilla by intermaxillary
fixation, open reduction, and interosseous wiring of the infraorbital rims
and plating of the accompanying fractures of the nose, nasal septum, and
orbital floor.

86. LE FORT III (CRANIOFACIAL DISJUNCTION)
• Midface fracture results when the traumatic force is of sufficient magnitude to
completely separate the middle third of the facial skeleton from the cranium.
• The fracture plane usually extends from the nasal bone and frontal process of
the maxilla or nasofrontal and maxillofrontal sutures, across the orbital floor,
through the ethmoid air cells and sphenoid sinus to the zygomatico-frontal
sutures
• More posteriorly and inferiorly, the fracture plane passes across the
pterygomaxillary fissure and separates the bases of the pterygoid plates from
the sphenoid bone.
• If the maxilla is displaced and freely movable, a fracture must also have
occurred in the area of the zygomaticotemporal suture.
• The zygomatic bone or zygomatic arch is involved, these injuries are
associated with multiple other maxillary fractures.
• Mandibular fractures are also observed in half the cases.

87. LE FORT III (CRANIOFACIAL DISJUNCTION)
• Clinical Features
• Craniofacial disjunction produces a clinical appearance similar to that of a
pyramidal fracture.
• The soft tissue injuries are severe, with massive edema.
• The nose may be blocked with blood or blood clot, or cerebrospinal fluid
rhinorrhea may be present.
• Bleeding may occur into the periorbital tissues and the conjunctiva, and a
number of eye signs of neurologic importance are likely to be present.
• “Dished-in” or concave deformity of the face is characteristic of this fracture
pattern, as is an anterior open bite because of the retroclined positions of the
maxillary incisors with only the posterior teeth in occlusion.
• Intraoral and Extraoral palpation reveals irregular contours and step
deformities, and crepitation is also apparent when the fragments are moved

88. LE FORT III (CRANIOFACIAL DISJUNCTION)
• Radiographic Features
• It is virtually impossible to document these multiple fractures with plain films.
• CT images in concert with the clinical information are required.
• The main radiographic findings are distractions of the frontonasal,
frontomaxillary, zygomaticofrontal, and zygomaticotemporal sutures and
fractures through the nasal bone, frontal process of the maxilla, orbital floor,
and pterygoid plates.
• Associated fractures involving the walls of all the paranasal sinuses will result
in radiopaque air-fluid levels with mucosal thickening.
• Three dimensional reconstructions show the fracture planes and the large
bone fragments.
• Management; Control of Hemorrhage, Suturing, Fixation

92. MONITORING THE HEALING AFTER TRAUMA
• Radiographic examination of the facial bones after trauma is usually necessary to
measure the degree of reduction from treatment and to monitor the continued
immobilization of the fracture site during repair.
• Typically, monitoring of this type is accomplished by use of plain radiography.
• The monitoring of fracture repair should include examination of both the alignment
of the cortical plates of the involved bone and remodeling and remineralization of the
fracture site.
• During normal healing the fracture line increases in width about 2 weeks after
reduction of the fracture.
• This results from the resorption of the fractured ends and small sequestered
fragments of bone.
• Evidence of remineralization usually occurs 5 to 6 weeks after treatment.
• Unlike the long bones of the skeleton, rarely is a callus formed in healing jaw
fractures.

93. REFERENCES
• Chapter 29: Trauma to the Teeth and Facial Structures

94. THANK YOU!