Orofacial infections - Treatment

Draining a dental abscess under LA

Typically for odontogenic infections which have now spread beyond the buccal bone, they can be drained under LA provided the infection has not spread to other deeper spaces. These patients will present characteristically with fullness in the buccal sulcus. Once you have made the decision that the infection is amenable to I&D under LA, gather the equipment.
You will need:
1) Local anaesthetic
2) Blade
3) Gauze
4) Saline in a syringe
5) Basic dental kit
6) Periosteal elevator/instrument which can be used to strip/lift the periosteum
7) Suction if possible

In terms of performing the drainage, the following steps can be used as guidance:
1) Administer LA
2) Identify the point of maximum fluctuance
3) Make an incision over the point of maximum fluctuance, ensure your blade goes down to bone and the direction of the incision is towards the bone NOT straight through the sulcus.
4) Ensure you are underneath the periosteum as there is where the pus will have collected
5) Explore the incision with needle holders to milk the pus
6) Irrigate the area and incision with saline
7) Oral antibiotics e.g. co-amoxiclav 625mg TDS 5 days (Remember to check allergy status)

When doing this procedure, do not suture the incision closed to allow continued drainage. Also, you need to ensure you are underneath the periosteum. There are numerous occasions where SHOs have made incisions and have not found any pus. However when a senior arrives and lifts the periosteum, a large volume of pus starts draining. Remember to take care in certain anatomical locations to prevent damage to underlying structures e.g. mental nerve, facial artery.

Figure 1. Buccal abscess with area of fluctuance [1]
Figure 2. Incision and drainage. NOTE the direction
of the incision [2]

Incision and drainage of an infected cyst under LA

The principles of draining a sebaceous cyst are very similar to a dental abscess however the main difference is that you will make a superficial incision to relieve the tension of the wound and allow the pus to escape.
This becomes especially important as these cysts may appear on areas of the face where vital structures may be located e.g. marginal mandibular branch of the facial nerve.
Equipment required:
1) Local anaesthetic
2) Blade
3) Gauze
4) Saline in a syringe
5) Instrument to explore incision
6) Suction if possible

1) Administer LA
2) Make a small superficial incision over the swelling
3) Apply pressure around the swelling to milk out the pus and explore the wound
4) At this stage you may wish to swab the pus for MC&S
5) Irrigate the wound thoroughly with saline
6) Oral antibiotics – flucloxacillin 500mg QDS 5-7 days
7) Leave the wound open to allow continued pus drainage and provide dressings

Figure 3. Branches of facial nerve [3]

When performing procedures on the skin especially the face, the location of the incision/excision should be considered with skin tension lines. These lines are referred to as Langer lines and have significant implications for the design of your surgical incision in terms of location. You should always aim to align your incision/excision with Langers lines to ensure there is minimal tension in the area. This minimises wound contraction and contributes to a more aesthetic outcome.

Figure 4. Langers lines [4]

I&D, exploration and debridement under GA

For patients who require drainage of the abscess under GA, it is important to be aware of the procedure they have undergone so that you understand how to manage them when they return to the ward.
It is important to remember that the main objectives of treating these patients is:
1) To secure the airway
2) Achieve drainage
3) Remove the source of the infection otherwise there will be a recollection
Generally whichever fascial spaces there are collections in, will be explored. This is why having a CT scan in these patients can be useful as it can guide where you need to make your incisions. Remember to always consider the underlying anatomy e.g. CN VII branches.

Returning to the ward

Once the operation has been completed, these patients will return to the ward with drains in-situ. There are many types of drains however in my experience, a corrugated drain is the most common one used, and they are sutured in place. The purpose of these drains is to keep the incision patent therefore allowing any pus which may remain to drain. Therefore they will also prevent any pus from recollecting.
The patient should also be written up for IV antibiotics. Intra-operatively, the surgeons will send a pus sample for MC&S. Therefore, you should be checking the micro results to ensure the correct antibiotics have been prescribed.
It’s important to be able to identify whether or not these patients are improving or perhaps may even be recollecting. As with most infections, you are looking to see a downwards trend in terms of WCC and CRP and an overall improvement in their observations. Patient’s themselves will let you know when they are feeling better.
If however, there is still a significant volume of pus being drained and a swelling redeveloping, raise this with a senior. Usually, the WCC and CRP will indicate persistent infection and in this case it is important to re-establish where the residual infection is. If a recollection of pus is suspected, your seniors may decide to request another CT scan.
In these cases, if the patient starts to deteriorate or the infection worsens, they may have to return to theatre for EUA, exploration and further debridement. With regards to trismus, this can take some time to improve therefore its worthwhile demonstrating jaw opening exercises to these patients for them to practice at home once they have been discharged.
As the patient is improving, the drains need to be removed. Note they are only removed once your seniors are happy that there is no remaining pus in the wound and there is no longer any drainage.

Patient should be sent home with oral antibiotics and ideally reviewed on an outpatient basis 5-7 days later.

Figure 5. Typical incision sites for extraoral incision and drainage [5]
Figure 6. Sublingual and buccal corrugated
drains [6]


[1] Image from: Buccal Mucosa & Alveolus [Internet]. OtoRhinoLaryngology Portal. 2020. Available from: https://www.drrahmatorlummc.com/buccalmucosaalveolus.htm
[2] Image from: File:Incision and drainage mouth.png - Wikimedia Commons [Internet]. Commons.wikimedia.org. 2020. Available from: https://commons.wikimedia.org/wiki/File:Incision_and_drainage_mouth.png
[3] Image from: Lesser Petrosal Nerve - an overview | ScienceDirect Topics [Internet]. Sciencedirect.com. 2020. Available from: https://www.sciencedirect.com/topics/neuroscience/lesser-petrosal-nerve
[4] Hosein, Mohammad & Motamedi, Mohammad & Mortazavi, Seyed & Behnia, Hossein & Yaghmaei, Masoud & Khodayari, Abbas & Akhlaghi, Fahimeh & Shams, Mohammad & Marandi, Rashid. (2013). Maxillofacial Reconstruction of Ballistic Injuries.
[5] Typical incision sites for extraoral incision and drainage. From Lui DW and Abubaker AO: Odontogenic Infection. In Kademani D and Tiwana PS, editors: Atlas of Oral and Maxillofacial Surgery, St. Louis, 2016, Saunders.
[6] Kassam K, Messiha A, Heliotis M. Ludwig’s Angina: The Original Angina. Case Reports in Surgery. 2013;2013:1-4.