Surgical Aspects of the Maxillary Antrum Flashcards
What shape is the maxillary antrum?
Pyramidal shape
Apex is facing laterally
What is the roof of the antrum?
Orbital floor (brittle and thin) = more likely to fracture - where infraorbital nerves come through Infraorbital bundle traverses
Medial wall of the maxillary antrum?
Lateral wall
Contains ostium
Cartilaginous in places
Floor of the maxillary antrum?
Alveolar process of maxilla Hard palate Thinnest near tooth bearing alveolus In children adjacent to nasal floor In adults 5-10mm lower Close to apices of teeth
Anterior wall of the maxillary sinus?
The cheek area
- Also forms lateral wall with lateral maxilla
- Should call antero-lateral wall
- Contains canine fossa = infection of canine can extend into maxillary sinus
- Thinnest part <2mm thick
- Good for surgical access
What does the maxillary sinus drain into?
Drains into nose via ostium
Ostium is halfway up the medial wall
Efficient cilia - beat towards ostium
What is an oro-antral communication?
An open communication between the oral cavity and maxillary sinus
Floor can extend from molar region to canine
Root apices closely associated
Most common tooth/root to have an OAC?
Palatal root of first molar
How to diagnose an OAC?
Clinical/radiographic signs:
- Movement of antral lining during respiration
- Emanating bubbles from socket during respiration
- Hollow sound when aspirating socket
- Fogging of mirror
- Extracted tooth attached to concave bone or fractured tuberosity
- Post op radiograph - defect sinus floor
Conservative management of OACs?
Many OACs undetected
- Heal spontaneously
Instructions
- No nose blowing
- OHI
Antibiotics - broad spectrum (penicillin)
Splints
Decongestants (eucalyptus oil)
Active treatment for OACs?
Suturing
- Resorbable/non-resorbable
- Packing - resorbable/oxidised cellulose
Non-resorbable - fistula: BIPP (ismuth iodoform paraffin paste), ribbon gauze
Splints
Antibiotics, decongestants
What is a fistula?
Communication of the oral cavity and maxillary sinus lined by epithelium (>7 days after surgery)
What can a healed OAC form?
An oro-antral fistula
Signs and symptoms of oro-antral fistula?
Purulent discharge
Bad taste
Liquid discharge through nose
Air escape - both directions (do NOT do acutely)
- Can have false negative result due to infection/debris
Episodic sinusitis
Nasal voice
Epistaxis
Prolapse of antral mucosa into mouth
Whistling noise
Radiographic evidence - CBCT/Occipitomental
Types of surgical repair?
Buccal advancement flap
Buccal fat pad graft
Palatal rotation/palatal finger flap
Trapezoid flap
Surgical closure - buccal advancement flap features?
Raise full thickness mucoperiosteal buccal flap
Release periosteal fibres to bring it over the OAC
If a fistula cut the fistula out as well as the flap to remove the epi lining
Good success rate
Low morbidity
Good blood supply
BUT decrease in vestibular sulcus depth - prosthetic implications (E.G. difficulty with dentures)
Palatal rotation flap?
Relies on greater palatine artery Length/width ratio important - >2.5 = flap necrosis Painful donor site Seldom used, useful for larger OAFs Leave to heal by secondary intention
Buccal fat pad graft features?
Do a buccal advancement flap and take buccal fat and pull it into the hole before closing it up
What epi lines the maxillary sinus?
Lined by respiratory epithelium (ciliated pseudostratified columnar epithelium)
What is the largest paranasal sinus?
Maxillary sinus
Functions of the maxillary sinus?
Reduces weight of skull
Voice resonance
Humidification
Mucous production
Anatomical borders of the maxillary sinus?
Infraorbital surface of maxilla (Superior) Alveolar process (Inferior) Lateral wall of nose (Medial) Zygoma (Lateral) Maxilla (Anterior/medial/lateral)
OAC risk factors?
Long/ankylosed roots Lone standing molar Hypercementosis, bulbous roots Loss of apical periapical bone Pneumatisation of sinus Impacted upper molar Poor technique - excessive force Cleft lip and palate Root fracture
Risk factors of OACs?
Thinner antral floor (1-7mm)
Bone resorption related to chronic apical periodontitis
Early and complete increase risk of OAC
OAC management?
<2MM:
- Promote spontaneous healing
- Gentle irritation of socket and debridement of sharp bone
- Resorbable haemostatic agent (surgicel)
- Suturing loose edges
- Antral regime and review
- Vacuum splint
2-4mm = conservative vs surgical repair - assess risk factors
> 4mm or OAF = surgical repair
Common displaced foreign objects?
How to avoid displacing objects?
Upper 3rd molars 0.3-3.8% of iatrogenic cases of foreign body entrapment
Upper 6 palatal root >3rd molar > 2nd molar root
Avoid apical pressure
Controlled pressure and safe technique
Transalveolar approach of retrieving a displaced foreign object?
- Fill sinus with saline - use suction to retrieve root
- 2 or 3 sided buccal flap - flap design should permit closure with advancement:
- Flap elevated subperiostally
- Bone removal to enable visualisation and removal of interdental septae
- Retrieve root with tweezers
- Closure with buccal advancement (+/- fat pad or collagen membranes)
How to retrieve a displaced foreign object?
- Alveolar approach
- Caldwell-Luc approach
- Functional endoscopic sinus surgery (FESS)
Retrieve
Light
Suction
Locations - is it between mucosa and alveolar bone or between intact sinus lining and floor of sinus
Caldwell-Luc procedure?
Create incision in lateral aspect (premolar region)
Create buccal window = access into sinus
Flush object out
Pros caldwell-luc?
Trapdoor approach Good access Preserves alveolar bone Method of choice for delayed procedures Direct vision
Cons of caldwell-luc?
Trauma, loss of vitality to adjacent teeth Fistula formation Epistaxis Intraorbital nerve damage - Neuralgia - Paraesthesia
Functional endoscopic sinus surgery features?
Conservative
Maxillary sinus access via enlarged middle meatus antrosotomy
Minimises complications associated with surgical options
Expensive, time consuming
Risks of functional endoscopic sinus surgery?
Risks - infection, epistaxis, CSF leak, difficulty retrieving posterior/inferior or large foreign body
When choosing to delay retrieving a displaced foreign object, what should you do?
Document info (size, position) Radiograph - PA, OPT, OM, CT Suture socket Antibiotics Refer
Fractured tuberosity features?
Most distal aspect of maxilla Contains socket of 3rd molar Fracture - cause for concern: - Large OAC - Stability issue later for prosthetics Associated with upper molar extractions - usually 7, 8
Fractured tuberosity risk factors?
Divergent/dilacerated/ankylosed roots Removal of impacted upper molar Lone standing upper molar Pneumatised maxillary sinus Increased age Poor technique - Uncontrolled force, inadequate maxillary alveolus support, excessive elevation
Clinical signs of fractured tuberosity?
Tooth and tuberosity are felt to move synchronously with extraction
Fracture noise
Palatal tear
Bleeding
Assess - continue vs abandon extraction, immediate vs delayed repair?
How to manage fractured tuberositys IF it’s still attached to the periosteum? (realising fracture early)
- Rigid spliting to adjacent teeth (composite and ortho wire)
- Soft diet, antibiotics, rebook for surgical extaction in 6-8 weeks) - Or section crown to enable roots and tuberosity to heal and suture
- Soft diet, antibiotics. Rebook for surgical extraction 6-8 weeks - Remove fractured tuberosity (if small) - subperiosteal dissection of mucoperiosteum off the fragment
If fractured tuberosity completely separate from soft tissues +/- OAC management?
Smooth sharp edges residual bone
If no OAC - suture and antral regime and review
If OAC - treat according to defect size and antral regime and review
Symptoms of sinusitis?
Bacterial or viral Mimic toothache Nasal discharge Pressure - tender Pain when bending over/lying down
Tx of chronic sinusitis?
Bacterial - broad spectrum antibiotics (amoxicillin - if not working then co-amoxiclav), decongestants
- If not resolved refer to ENT
Chronic - antral wash out, nasal surgery
