Odontogenic sinusitis describes inflammation of the maxillary sinus secondary to dental pathology or dental procedures.
Odontogenic sinusitis accounts for 5-70% of cases of chronic maxillary sinusitis. It is the most common cause of unilateral maxillary sinusitis .
Sinusitis is a clinical diagnosis that relies on the presence of signs and symptoms 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.
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.
Sources vary as to whether iatrogenic causes or dental pathology are more common causes of odontogenic sinusitis . They can be classified as the following :
- oroantral communication/fistula following tooth extraction
- sinus lift procedure
- foreign body (e.g. dental restoration, root canal fillings, misplaced roots)
- periapical inflammatory pathology/apical periodontitis (most common)
- marginal periodontitis, usually with severe vertical bone loss
- combined endodontic-periodontic pathology
The tooth of origin is nearly always one of the maxillary molars or premolars, most commonly involving the first or second molars .
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.
Multiplanar evaluation of the maxillary molars and premolars and surrounding bone should be undertaken to identify a source, such as periapical lucency, periodontal bone loss, oroantral fistula, and exogenous dental reconstructive/restorative material.