What is an Oro-Antral Communication (OAC)?
This is a communication between the maxillary sinus /
antrum and the oral cavity / mouth.
What is an Oro-Antral Fistula?
If an OAC is not treated, this can become lined with
epithelium (skin). Hence, an oro-antral fistula is an
epithelised tract linking the maxillary sinus to the mouth;
the tract becomes 'permanent'.
(Alternative names for an OAC / OAF include oro-antral
fistulæ & oral fistulæ, sinus perforations and antra-oral
|Photos of Oro-Antral Communications
|CT Scan Showing Oro-Antral Fistula
|When an OAC is created, it allows the flow of food, smoke or fluid from the mouth
into the nose - not just these but also bacteria, fungi and viruses. This can set up a
maxillary sinusitis, which depending on how long the communication lasts for, may
either yield an acute / chronic maxillary sinusitis.
Causes of OAC’s:
The vast majority of OAC's are created when upper molars and premolars are
removed (almost 50%), tumours (18.5%), bone infections (osteomyelitis) (11%),
operations to access the maxillary sinus (Caldwell-Luc procedures) (7.5%), trauma
(7.5%), dentigerous cysts (3.7%), correction of septal perforations (3.7%),
perforation of the sinus floor from the tooth socket when trying to remove an upper
tooth and localised florid gum disease (HIV-related periodontitis) or tooth-tip
infections (chronic apical infection).
As a very broad generalisation, the following may be thought to predispose to an
OAC being formed:
- Proximity of sinus floor / tuberosity
- Thickened tooth cement (hypercementosis) / tooth fused to jaw bone
- Infected teeth / long-standing decay
- Marked periodontitis / gum disease
- Previous history of OAC’s.
Treatment of the Acute OAC:
If an OAC has been created, then:
- Do not probe the defect
- Promote good blood clot
- The gingival / gum margins around the socket should be approximated as
close as possible
- Physical agents placed in the socket to stop excess bleeding (Surgicel,
Spongostan or Haemocollagene)
- Antibiotics should be prescribed (Amoxycillin, Doxycycline)
- Nasal decongestants can be used (Ephedrine nasal drops, Oxymetazoline)
- Steam inhalations can be used (Menthol & Eucalyptus)
- Antiseptic mouth-wash should be used (Corsodyl)
- No nose-blowing or smoking
How to Recognise the Chronic OAC / OAF:
The OAC is likely to become chronic if:
- OAC is greater than 5mm in diameter
- Gingival tissues / gums around the socket can’t be approximated
- Post-op régime is not followed
- Wound dehiscence / breakdown
- Enucleation of a dental / dentigerous cyst
- May develop 4 – 6 weeks post-extraction
- Problems with smoking, eating or drinking
- Cacogeusia / foul taste
- Chronic maxillary sinusitis
- Antral polyp herniating into the mouth
- Purulent (pus) discharge from nose
Treatment of the Chronic / Larger OAC / OAF:
- The OAC is assessed with X-rays & CT's.
- The OAC may still spontaneously close if a cover plate used.
- If the OAC / OAF needs closing, pre-op antibiotic & decongestant régime
(starting 3 – 7 days pre-op).
The OAF is closed using the following flaps:
Buccal Advancement Flap most common. Described by Rehrmann & made
popular by Berger.
- Antibiotics (Amoxycillin, Doxycycline)
- Nasal decongestants (Ephedrine nasal drops, Oxymetazoline)
- Steam inhalations (Menthol & Eucalyptus)
- Antiseptic mouth-wash (Corsodyl)
- No nose-blowing or smoking
|Last Updated 5th September 2017
|Various Treatment Modalities for the Closure of Oro-Antral Communications