Maxillary Sinusitis of Endodontic Origin (MSEO)

What is Maxillary Sinusitis of Endodontic Origin (MSEO)?

Maxillary Sinusitis of Endodontic Origin (MSEO) is a sinus infection that originates secondarily to an endodontic infection in a posterior maxillary tooth. Some studies indicate that more than 40% of maxillary sinusitis cases are caused by a tooth infection. However, MSEO often goes undetected in routine ENT exams and conventional medical CT scans.

How is MSEO diagnosed?

Diagnosis of MSEO can be confirmed with a routine endodontic evaluation and Cone Beam CT (CBCT) imaging. A CBCT scan obtained on a high resolution setting will better detect the most subtle signs of MSEO. Symptoms of MSEO may include congestion, runny nose, post-nasal drip, facial pain, or foul odor. Surprisingly, the tooth responsible for the infection may feel completely normal.

What is the treatment for MSEO?

Conventional endodontic therapy leads to successful resolution of MSEO in many cases and sinus symptoms often resolve within a few weeks following treatment. A follow-up evaluation (no additional charge) is recommended to confirm resolution of MSEO. If signs or symptoms persist, you may be referred to your ENT for further evaluation and treatment.