Oro-Antral Communications, Mouth-Sinus Holes

Exodontia.Info

Mouth-Sinus Holes
(Oro-Antral Communications)

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 &
oral fistulæ, sinus perforations and antra-oral fistulæ).

Photos of Oro-Antral Communications

CT Scan Showing Oro-Antral Fistula

When an OAC is created, it allows the flow of food,
smokeor fluid from the mouth into the nose - not just
these but also bacteria, fungi and viruses. This can set
up
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).

Predictive Factors:

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 / tooth fused to jaw bone
Infected teeth / long-standing decay
Marked periodontitis / gum disease
Lone-standing
Previous history of OAC’s.

Treatment of the Acute OAF:

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, S pongostan or Haemocollagene)
Antibiotics should be prescribed (Amoxycillin,
D oxycycline)
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).