Management of the maxillary antrum Flashcards
Why is the maxillary sinus important in dentistry?
- roots of the upper molars/ premolars closely related to the antrum and share a common innervation
- peri-operative complications such as OA communication, roots in antrum, fracture tuberosity, extruded root canal materials
- sinus pathology can cause symptoms like toothache - most commonly dentists are asked to establish if the pain is of dental or antral origin
- sinus pathology can present in the mouth or may be seen on a dental radiograph
What is a worrying sinus pathology that can present inside the mouth?
maxillary sinus cancer - can cause erosion of the bone into the mouth and present as an intra-oral lesion
What may a maxillary sinus cyst cause in the mouth?
displacement of teeth and a communication between the sinus and the mouth
What are the paranasal sinuses?
- air-containing sacs lines by ciliated epithelium communicating with the nasal cavity
- 4 pairs - frontal, ethmoid, sphenoid, maxillary
Label these
What is the general shape and volume of the maxillary sinus?
pyramidal shape, volume of 15-30ml
What measurements is the largest maxillary sinus?
3.5 x 2.5 x 3.2cm
Where is the floor of the maxillary sinus in relation to the nasal floor?
12mm below
When does the maxillary antrum develop, and at what ages does it reach key sizes?
develops at 3 months IUL, 30% size by 9yrs, full size 18yrs and continues to enlarge as we age
What anatomy is the maxillary sinus related to?
the orbit, infra-orbital nerve, nasolacrimal duct, posterior teeth and lateral wall of the nose, pterygopalatine fossa and maxillary artery
Where does the maxillary sinus drain?
into the middle meatus through a 2.4mm diameter ostium which is two thirds up the medial wall of the sinus
What is the physiological role of the maxillary sinus?
poorly understood
What radiographs would be used to view the maxillary sinus?
- occipitomental
- DPT, periapicals
What imaging techniques would be used to view the maxillary sinus if you believed something was occupying it?
CT scan/MRI
endoscopy also commonly used now, antral tap used to be used to allow drainage
What pattern do the ciliated epithelium of the maxillary sinus beat in?
beat in spiralling pattern up to the ostium, against gravity
What is transillumination of sinuses?
scope with light put up the patient’s nose, if the sinus illuminates it is healthy, if not then it indicates there is something present in the sinus
What will extrusion of material through the root apex into the antrum result in?
as you have introduced a foreign body into a sterile cavity an inflammatory reaction will happen and the patient will likely get infection/sinusitis
What is the consequence and treatment of root displacement into the maxillary antrum?
by introducing foreign body covered in bacterial contaminants into the sterile antrum it will cause a bacterial infection, so you wouldn’t want to leave a displaced root in the sinus so surgery would be required to remove it, and because a communication has been created this will need to be closed
What does this CT scan show?
molar tooth displaced into the maxillary antrum
What are the common pathologies of the maxillary sinuses?
- infective sinusitis - bacterial, viral, fungal, 10% dental origin, OAF
- non-infective sinusitis - allergic, vasomotor, septal deviation predisposes, foreign body (roots/teeth)
- fractures
- tumours/cysts
What do most infective sinusitises follow on from?
viral infection e.g. a cold or the flu
Usually what is acute infective sinusitis, and what bacteria commonly cause it?
- bacterial infection which follows a viral infection
- commonly caused by Strep. Pneumoniae, H. influenzae but Moraxella catarrhalis, Staph. Auereus and alpha haemolytic strep also found
How is acute infective sinusitis diagnosed?
diagnosis on clinical grounds no need for radiograph other than radiographs used to rule out odontogenic infection
Why does leaning forward worsen the pain felt in acute infective sinusitis?
the fluid in the sinuses will move forward and put pressure on the anterior superior alveolar nerve
What are the signs and symptoms of acute infective sinusitis?
pain, tenderness across area worsens on bending over, without swelling, posterior teeth TTP, post nasal drip, mucoputulent discharge
- maxillary toothache
- poor response to nasal decongestants
- history of coloured discharge
- purulent nasal secretion
What does this image show about the maxillary sinuses?
sinus on left full of mucopurelent discharge that isn’t discharging through the ostium
sinus on right also has a fluid level but not as full
How is acute sinusitis managed?
most fit and healthy people only need something to encourage discharge of the sinus, something that will open up the ostium
- mucolytics, inhalation for 2 weeks
- antimicrobials only in severe cases or immunocompromised - need to be effective against penicillinase producing bacteria therefore augmentin, doxycycline, clarithromycin
In order, what does the SDCEP ‘drug prescribing for dentists’ suggest to use for management of acute sinusitis?
- inhalations to facilitate draining of the sinuses
- epinephrine nasal drops 0.5% 3/day for 1 week
- Pen V 500mg 4/day for 7 days
- doxycycline 100mg for 1 week, 200mg on the first day
What issues may predispose someone to sinusitis?
mechanical obstruction of ostium
- oedema of nasal mucosa
- polyps
- septal deviation
impaired mucus clearance
- poor ciliary action
- abnormally thick or sticky mucus (e.g. in cystic fibrosis)
What is chronic sinusitis?
ongoing low-grade symptoms of sinusitis
How may chronic sinusitis be treated?
drainage (antral lavage, intranasal antrostomy) and metronidazole with amoxycillin/erythromycin
If an OAF is not present, what may chronic sinusitis be suggestive of?
immunocompromise
What may chronic sinusitis be caused by?
OAF, possible anatomical drainage problem e.g. deviated nasal septum etc.
What would be done if chronic sinusitis is being caused by an OAF?
surgical closure of OAF defect
What is this?
antral mucocoele- cyst that has formed in the antral lining
What may an antral cyst/mucocoele cause?
mechanical blockage of ostium restricting drainage, may result in chronic sinusitis
What does this show?
mechanical obstruction of the ostium by a displaced root
What are some significant complications of sinusitis?
- brain abscesses
- orbital cellulitis
- cavernous sinus thrombosis
What is OAC caused by?
caused following extraction of posterior teeth, tuberosity fracture, middle third fracture, also malignancy/pathology
What are the symptoms of an OAC?
passage of fluid down nose, passage of air into mouth, alteration of voice, unilateral apistaxsis or nasal obstruction
What will happen if an OAC which has not spontaneously closed by itself is left untreated?
fistula develops which can cause persistent sinusitis, unilateral nasal discharge, intra-oral antral polyp, cacogeusia and facial pain
How is the risk of OAC assessed and consented for?
- extracting any upper molars and occasionally premolars, particularly older patients as sinus increases in size as we age
- if the radiograph suggests a close relationship
- inform the patient of the risk, what to expect afterwards if this happens
- outline how this complication is managed
What do the yellow and blue arrows point to and what does this indicate?
yellow - where alveolus stops
blue - floor of sinus
superimposition of root apices over sinus
If you know you have created an oro-antral communication what should you do?
- ideally close immediately - buccal advancement flap
- plate or modified denture
- antibiotics, ephedrine drops, mucolytic inhalations
- avoid nose blowing
- if communication of greater than 5mm spontaneous closure unlikely
Summary of management of maxillary sinuses lecture
