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Allergy, Nose & Sinus

Sinusitis from a tooth infection (WARNING – GRAPHIC MEDICAL IMAGES)

February 10, 2020
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Dr Gan recently saw a patient, Mr A, who complained of left cheek pressure and fullness over the last one year. This was associated with a left blocked nose and postnasal drip (mucous dripping down the back of the nose). He has visited a few doctors and had four courses of oral antibiotics. The symptoms did improve with antibiotics and nasal douche (nose wash with salt water) but they never resolve completely.

Dr Gan performed a nasoendoscopy (scope through the nose) on Mr A. It showed a congested left sinus outflow track with an inflammatory polyp. Mucopus (mixture of mucous and pus) can be seen flowing from the sinus to the back of his nose and throat (resulting in postnasal drip). The rest of his ENT and head & neck examination was unremarkable.

 

Chronic Sinus Infection

A nasoendoscopic view of the left nose showing an inflammatory polyp

 

Mucopus

A nasoendoscopic view of the back of the left nose showing mucopus from the obstructed sinus outflow track

 

Based on the clinical history and nasoendoscopy findings, Mr A was diagnosed with chronic sinusitis (sinus infection). A sample of the mucopus from Mr A’s nose was taken for culture (sent to the lab to grow the bacteria for antibiotic sensitivity). Given the chronicity of his symptoms, Mr A was advised to undergo a CT scan (special series of X-rays) of his nose and sinuses to investigate the cause of his persistent or refractory sinusitis. However, Mr A was not keen and would like to be more conservative in his treatment.

As M A’s previous courses of antibiotics ranged from 5-7 days. The duration of treatment may have been inadequate for his sinus infection. Hence, Mr A was given a two weeks course of “strong” antibiotics along with nasal douche and nasal steroid sprays. Upon review in the clinic 2 weeks later, Mr A’s symptoms improved, but again still persistent and troubling to him. The culture from the nose did not show any bacterial growth. Mr A was left with limited options and agreed to undergo a CT scan of his nose and sinuses. The scan showed that his left cheek sinus (maxillary sinus) was completely filled with mucopus. It also showed that his left upper molar tooth has a dental cyst that has ruptured into the maxillary sinus.

 

Sinusitis from tooth infection

A CT scan of the nose & sinus showing a completely blocked and infected left maxillary sinus. There was also a left upper rear tooth (molar) with a cyst that has ruptured into the maxillary sinus

 

Mr A denied any toothaches but did complain of some sensitivity in his gums. He was referred to a dental surgeon who confirmed that the left upper molar dental cyst was infected. Hence, the protruded upper molar in the sinus was likely the source of Mr A’s recalcitrant left maxillary sinus infection. Mr A underwent left functional endoscopic sinus surgery (aka FESS or sinus surgery), extraction of the left upper molar/dental cyst and closure of the dental wound.

During surgery, there was copious amount of pus seen in the left maxillary sinus. This was flushed out completely. Immediately post surgery, Mr A felt the relieve from the pressure in his left cheek. Mr A was last seen about a month after surgery. His nose symptoms and pressure in the left cheek have completely resolved.

 

Sinus Infection

An endoscopic view of the opening of the left maxillary sinus in the nose during surgery. The scope is a 30 degrees scope looking out 30 degrees to the side.

 

Maxillary Sinus

After the pus was suctioned out, the back wall and floor of the maxillary sinus can be seen. This is a view on a 30 degree scope (looking to the side)

 

The roots of the upper molars (upper rear teeth) are very close to the floor of the maxillary sinus. In some patients, their upper molars may protrude into the maxillary sinus. An infected tooth in the sinus may be a cause of sinus infection. It is important to remove the cause or source of the sinus infection or the sinus infection will never clear.

 

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If you are experiencing persistent ENT symptoms or have concerns about your ear, nose, or throat health, our team is here to help. Book an appointment with our ENT specialist for a professional assessment and personalised care plan.

You may schedule your visit conveniently via WhatsApp at +65 9058 2480,, through our online enquiry form, or by calling +65 6253 7296. We look forward to supporting your ENT health with attentive and professional care.

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Dr Gan Eng Cern — ENT Specialist Singapore
Gold Award 2020
Best in Singapore
FAMS (ORL)
Senior ENT Specialist

Dr Gan Eng Cern

Ear, Nose & Throat Specialist · Rhinology & Endoscopic Skull Base Surgery

MBBS (Australia) MRCS (Edinburgh) MMed (ORL) Singapore FAMS (ORL)

Dr Gan is a fellowship-trained ENT specialist with deep expertise in rhinology and endoscopic skull base surgery. He completed subspecialty training at St Paul's Sinus Centre, University of British Columbia, Vancouver — a globally recognised centre for nose and sinus care. He has served as Senior Clinical Lecturer at NUS Yong Loo Lin School of Medicine and has published research in international peer-reviewed ENT journals.

Rhinology Fellowship — UBC Vancouver
Senior Lecturer — NUS Yong Loo Lin
7 Professional Awards
20+ Years ENT Experience
Published ENT Researcher
Speaks: English 中文 Bahasa Melayu Hokkien

Practical ENT articles written or medically reviewed by Dr Gan Eng Cern

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