Is functional endoscopic sinus surgery (FESS) indicated prior to tooth extraction in cases of odontogenic sinusitis?

FESS Should NOT Be Performed Prior to Tooth Extraction in Odontogenic Sinusitis

The evidence strongly supports addressing the dental source first through tooth extraction and medical management, reserving FESS only for cases that fail initial dental treatment or have specific high-risk features.

Treatment Algorithm for Odontogenic Sinusitis

First-Line Approach: Dental Treatment + Medical Management

• Initial treatment should consist of tooth extraction (addressing the odontogenic source) combined with antibiotics and saline nasal irrigation 1, 2
• Approximately 67% of odontogenic sinusitis cases caused by dental caries and periapical abscess resolve with dental treatment and medical management alone, without requiring FESS 1
• Antibiotics should target both aerobic and anaerobic pathogens, with amoxicillin/clavulanic acid 1g three times daily plus metronidazole 500mg three times daily for 7-10 days being a reasonable regimen 3

Indications for Early or Concurrent FESS

FESS should be considered upfront or early in the following specific scenarios:

• Ostiomeatal complex (OMC) involvement on CT imaging - this increases the likelihood of requiring FESS by 37-fold (OR 37.3) 4
• High Lund-Mackay scores - patients requiring FESS had significantly higher scores (8.3 vs 3.7), with each point increase doubling the odds of needing surgery (OR 2.0) 1, 4
• Active smoking - increases odds of requiring FESS by 33-fold (OR 33.4) 1
• Presence of oroantral fistula (OAF) - all patients with OAF in one study required FESS 4, though combined FESS with OAF closure by local flap shows excellent outcomes 5
• Retained dental hardware in the sinus - all such patients required FESS 4
• Recent dental procedure as the etiology - increases odds of requiring FESS by 7.4-fold (OR 7.4) 4

When FESS Becomes Necessary After Initial Treatment

• Persistence of signs and symptoms beyond 3 weeks despite dental treatment and appropriate antibiotics warrants CT evaluation and consideration for FESS 3
• Approximately 33-48% of odontogenic sinusitis patients ultimately require FESS after failing dental and medical management 1, 4
• FESS is indicated when there is radiographic evidence of persistent disease with clinical symptoms including facial pain/pressure, purulent discharge, or nasal congestion lasting more than 4 weeks despite appropriate treatment 6

Critical Pitfalls to Avoid

Do not perform FESS before addressing the dental source - the tooth extraction must occur to eliminate the primary infectious nidus. FESS alone without dental treatment will likely fail, as the ongoing odontogenic source will perpetuate the sinusitis 2.

Do not delay dental treatment in favor of prolonged medical management - while antibiotics are important adjunctive therapy, they cannot cure odontogenic sinusitis without source control through tooth extraction 1, 2.

Do not assume all odontogenic sinusitis requires FESS - two-thirds of cases resolve with dental treatment alone, making routine upfront FESS unnecessary and potentially exposing patients to avoidable surgical risks 1.

Multidisciplinary Coordination

• When graft material or foreign bodies are dislocated inside the sinus, simultaneous or coordinated FESS with intraoral approach may be necessary 3
• Consultation between oral surgeons and otolaryngologists is recommended before performing procedures like the modified Caldwell-Luc approach to determine if simultaneous FESS is needed 6
• The modified Caldwell-Luc approach (accessing maxillary sinus through canine fossa) can be effective in 89% of odontogenic sinusitis cases without requiring FESS 6