Odontogenic sinusitis involving the frontal sinus: is middle meatal antrostomy enough?

Objective/hypothesis: Inflammatory conditions of the posterior maxillary teeth may cause odontogenic sinusitis (OS), which most commonly involves the maxillary sinus due to its proximity to those teeth. The infective process frequently spreads outside the maxillary sinus, involving the anterior ethmoid and the frontal sinuses. The underlying odontogenic condition must be addressed before or during the surgical procedure. The role of frontal sinusotomy in this setting has not been studied. The aim of this study is to present the surgical outcome of patients who presented with OS involving the frontal sinus and were managed by middle meatal antrostomy alone. Study design: Prospective cohort study. Methods: All patients operated in our department due to OS involving the frontal sinus from November 2015 to December 2017 were recruited. Their demographics, complaints, imaging and endoscopic findings, surgical features and outcome were analyzed. Results: Twenty-five patients (male-to-female ratio 9:16) with a median age of 49 years (IQR = 43–53) were enrolled. The maxillary, frontal and anterior ethmoid sinuses were involved in each case, and each patient underwent maxillary middle meatal antrostomy alone. The median follow-up was 10 months, and no signs of active frontal disease were detected by postoperative endoscopy in any patient. Conclusion: Frontal sinusotomy is apparently not necessary to resolve OS involving the frontal sinus. The frontal sinusitis may reflect a reactive process that regresses spontaneously once the underlying odontogenic condition is addressed and a middle meatal antrostomy had been performed. Level of evidence: 2B.