9 - Maxillary sinuses Flashcards
What are the sinuses in the skull?
- frontal
- ethmoidal air cells
- sphenoid
- maxillary
What is the function of the paranasal sinuses?
- resonance of voice
- warm inspired air (via their blood supply)
- reduce weight of skull
Describe the maxillary sinus.
- the largest air sinus
- also known as the maxillary antrum
- pyramid shaped cavity within the maxilla
- average 15ml volume
Describe the openings of the maxillary sinus.
- middle meatus aka hiatus semilunaris
- opening is 4mm diameter
- located superiorly on medial wall of sinus
- mucosa lined
Describe the relationship of the maxillary roots and the maxillary sinus.
- can sometimes project into floor of maxillary sinus
- roots can perforate bone so that only mucosa covers them
- sometimes the bone is very thin, this is only of concern if an extraction is required or there is pathology assoicated with the roots
Describe the epithelium of the sinus.
Pseudostratified ciliated columnar epithelium
What is the function of the cilia in the epithelium of the maxillary sinus?
- mobilise trapped particulate matter and foreign material in the sinus
- move material towards the ostia for elimination via the nasal cavity
What is the clinical significance of the maxillary sinus in dentistry?
- OAC
- OAF
- root in antrum
- sinusitis
- benign and malignant lesions
Describe the flap design for a buccal advancement flap.
- 3-sided flap design
- relieving incisions should be parallel (ish) medial and distal up towards the buccal sulus
- raise the flap
- trimming buccal bone is sometimes required
- incise/score periosteum to ensure flap can be closed without tension (fresh blade)
- suture socket and relieving incisions
How may patients present with an OAF?
- fluid comes out their nose when they drink fluids
- nasal quality of speech
- issues playing instruments
- smoking/using straw difficult
- bad taste/odour or post nasal drip
- pain/sinusitis symtoms
- unilateral drainage / salty drainage
How do you manage an OAF?
- excise sinus tract prior to performing buccal advancement flap
- antral washout sometimes performed (unpleasant for patent but aids with sinus cleanse)
What are the different flap design options for closing an OAC/F?
- buccal advancement flap
- buccal fat pad with buccal advancement flap
- palatal flap
- bone graft/collagen membrane
Describe a buccal fat pad with buccal advancement flap.
- incisions are extended into buccal sulcus
- buccal fat is pulled down from fat pad
- fat is sutured into socket with dissolving stitches
- buccal advancement flap as normal
- can result in facial asymmetries
Describe a palatal flap.
- flap design cut into palatal
- rotated to cover socket
- sutured into place
- can be very painful as exposed bone is left where flap was cut
What are the causes of maxillary tuberosity fracturein extraction?
- single standing molar
- unknown unerupted molar/wisdom tooth
- pathological gemination/concrescence
- extracting in wrong order
- inadequate alveolar support
What is the correct order for extracting upper teeth?
Start most posterior
How do you diagnose a fractured tuberosity?
- noise
- movement visually or by supporting hand
- more than one tooth moving
- tear in soft tissue of palate
How do you manage a fractured tuberosity?
if discover early
- stop XLA
- reduce and stabilise
- with splint OR
- orthodontic buccal arch wire bonded with composite
if discover post XLA
- dissect out and close wound primary
If the fractured tuberosity is splinted, what are the next steps?
- remove/treat pulp
- ensure tooth is out of occlusion
- consider antibiotics
- POI
- remove tooth surgically 4-8 weeks later
How do you diagnose a root in the antrum?
Confirm radiographically +/- CBCT
How can roots in the antrum be retrieved?
- via extraction socket with suction and small curettes (close as OAC)
- Caldwell-Luc approach via buccal window in buccal sulcus
- ENT
What are the causes of sinusitis?
- viral infection (inflammation and oedema block ostia)
- mucociliary clearance pattern altered by allergens, inflammation
- bacterial overgrowth
What are the signs and symptoms of sinusitis?
- facial pain/headache
- pressure
- congestion/nasal obstruction
- paranasal drainage
- hyposmia (decreased sense of smell)
- fever/fatigue
- dental pain/ear pain
- halitosis
- cough
- anaesthesia/parathesia over cheek
What dental causes can present similarly to sinusitis?
- periapical abscess
- periodontal infection
- deep caries
- recent extraction socket
- TMD
- neuralgia
What findings on examination indicate sinusitis?
- discomfort on palpation of infraorbital region
- diffuse pain in maxillary teeth
- equal TTP of multiple teeth in same region
- pain worsens with head movement
What is the management of sinusitis?
SDCEP:
- usually self limiting
- advise local measures
- steam inhalation - antibiotic prescription
What risk is associated with the use of ephedrine nasal drops?- do not prescribe anymore (SDCEP)
Causes atrophy of the lining (do not use for more than 7 days)
When antibiotics be prescribed for sinusitis?
- persistent symptoms and or
- purulent discharge lasting at least 7 days OR
- symptoms are severe
what antibiotic to prescribe for sinusitis
Phenoxymethylpenicillin
- 500mg
- 5days
- four times a day
Doxycycline
- 100 mg
- 7 days
- 2 capsule on 1st day, 1 capsule afterwards
How do fungal infections affect the sinuses?
- rare
- can be cause of non resolving sinusitis
- can cause expansion of bony walls by increased mucus secretion and fungal growth
How does trauma cause sinusitis?
Violating the integrity of the bony cavity and sinus membrane
What can cause trauma to the maxillary sinuses?
- sinus wall fracture
- orbital floor fracture
- RCT
- tooth extractions
- dental implants/sinus lifts
- deep perio treatment
- nasal packing
- NG tubes
- nasal intubation
What other pathology should be considered in the sinuses?
- bengin sinus lesions (polyps, mucoceles, mucous retention cysts)
- odontogenic cysts/odontogenic tumours expanding into sinus
- malignant lesions
