oral medicine & Pathology

Abscess Associated with Odontogenic Infection : Imaging , clinical findings , pathology , treatment , epidemiology

   Abscess Associated with Odontogenic Infection

 

Epidemiology

  •  Dental infection and periodontal inflammation are common infections.
  • They may result in mandibular osteomyelitis if appropriate therapy is delayed.
  • Septicemia with resultant osteomyelitis is uncommon but may be encountered in the pediatric age group.
  • Mandibular osteomyelitis may spread into the adjacent medial pterygoid or masseter muscles resulting in masticator space infection.

Clinical Findings

  •   Osteomyelitis is associated with pain and fever.
  • In addition, patients with masticator space abscess will have varying degrees of trismus.
  • Clinical examination will reveal redness and swelling over the face.
  • A discharging sinus may also be evident on inspection.
  • Masticator space abscess usually occurs from an infected premolar or molar tooth from either the mandibular or the maxillary alveolar ridge

Pathology

  •   Patients with dental and periodontal disease usually have a history of poor oral hygiene.
  • In some patients the underlying cause is previous irradiation for head and neck malignancy.
  • The immune system may be further compromised by the institution of chemotherapy.
  • The most commonly cultured microorganism is StaphyLococcus. However, a wide variery of anaerobes may also be found.

Treatment

  •   The treatment consists of appropriate antibiotic coverage, removal of the infected tooth, and drainage of the masticator space abscess.

Imaging Findings

CT

  •  Mandibular osteomyelitis is characterized by osteolysis and erosion of the involved mandible.
  • This is associated with adjacent soft tissue swelling in the masseter or medial pterygoid muscle.
  • Infections of the mandible may extend deeply into the sublingual space or superficially into the buccal space.
  • Phlegmon is characterized by diffuse enhancement of the soft tissues.
  • An abscess will have a low attenuation center with enhancement of the surrounding soft tissues.
  • Air in the soft tissues may be present if the infection is due to gas-forming organisms

MR

  •  On T l -weighted M R imaging, the high signal intensiry of the mandibular marrow is replaced with intermediate signal intensiry in inflammatory tissue.
  • On T2-weighted images high signals can be seen in the marrow space and soft tissues of the masticator space.
  • There is diffuse enhancement of the soft tissue with infections due to phlegmon.
  • Abscess will show the characteristic enhancement.

Imaging Pearls

 In the evaluation of patients with a masticator space infection, bone algorithm must be obtained to evaluate for osteomyelitis of the mandibular or maxillary alveolar ridge from an infected tooth.

 

 

Abscess Associated with Odontogenic Infection 

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