Odontogenic sinusitis

Odontogenic sinusitis describes inflammation of the maxillary sinus secondary to dental pathology (e.g. dental caries, periapical abscess) or secondary to dental procedures (e.g. extraction, implants). 

OndotongeicOdontogenic sinusitis accounts for 105-40% of causes of chronic maxillary sinusitis.

Clinical presentation

Sinusitis is a clinical diagnosis that relies on the presence of signs and almost exclusively involvessymptoms such as facial pain/pressure/fullness, mucopurulent nasal drainage, nasal congestion/obstruction, and reduction in sense of smell. To establish a diagnosis of chronic sinusitis, these symptoms should be present longer than 12 weeks despite attempts at medical management. Dental pain in odontogenic sinusitis can occur but is often absent. Patients who have imaging evidence of sinus mucosal inflammation are not necessarily symptomatic.

Pathology

Odontogenic sinusitis results from the spread of infection or inflammation from the teeth to the maxillary sinus via perforation of the sinus floor and disruption of the Schneiderian membrane.

Etiology

Sources vary as to whether iatrogenic causes or dental pathology are more common causes of odontogenic sinusitis ⁴. IsolatedThey can be classified as the following ³:

Iatrogenic causes:

• oroantral communication/fistula following tooth extraction
• sinus lift procedure
• foreign body (e.g. dental restoration, root canal fillings, misplaced roots)

Non-iatrogenic causes:

• periapical inflammatory pathology/apical periodontitis (most common)
• marginal periodontitis, usually with severe vertical bone loss
• combined endodontic-periodontic pathology

Location

The tooth of origin is nearly always one of the maxillary molars or premolars, most commonly involving the first or second molars ⁴.

Radiographic features

CT

The most common finding that supports, but does not establish, a diagnosis of odontogenic sinusitis is mucosal thickening in the inferior maxillary sinus (>2 mm is abnormal, >10 mm is marked/severe). Unilateral and isolated maxillary sinus opacification should raise the possibility of an odontogenic cause.