How To Drain a Tooth Abscess

• Periodontal or periapical abscess or cellulitis (ie, that began as a periapical abscess and is now spreading into adjacent soft tissues)

Absolute contraindications

• Signs of rapidly spreading infection (eg, high fever, tachycardia, tachypnea) or upper airway obstruction (eg, stridor, muffled voice): Such patients should be rapidly evaluated and managed in an emergency department.

• Infection spreading to the skin surface: Such patients should be referred to an oral and maxillofacial surgeon, for extraoral incision and drainage of the abscess.

Relative contraindications

• Infection in the path of needle insertion: Use nerve block, or other anesthesia.

• Coagulopathy*: When feasible, correct prior to procedure.

• Pregnancy: Avoid treatment in the 1st trimester if possible.

* Therapeutic anticoagulation (eg, for pulmonary embolism) increases the risk of bleeding with dental procedures, but this must be balanced against the increased risk of thrombosis (eg, stroke) if anticoagulation is reversed. Discuss any contemplated reversal with the clinician managing the patient's anticoagulation and then with the patient.

• Local anesthetic complications

• Spread of infection

• Failing to adequately drain the abscess

• Dental chair or a stretcher

• Light source for intraoral illumination

• Sterile gloves

• Mask and safety glasses, or a face shield

• Gauze pads

• Cotton-tipped applicators

• Dental mirror or tongue blade

• Suction

• Scalpels (#11 or #15 blade)

• Retractors (eg, Minnesota cheek retractor or tongue retractor)

• Needle driver

• Hemostat

• Suture (eg, 3-0 silk or other soft nonabsorbable suture)

• Penrose drain (1 cm) or substitute (eg, strip cut from a sterile glove)

Equipment to do local anesthesia:

• Dental aspirating syringe (with narrow barrel and custom injectable anesthetic cartridges) or other narrow barrel syringe (eg, 3 mL) with locking hub

• 25- or 27-gauge needle: 2 cm long for supraperiosteal infiltration; 3 cm long for nerve blocks

• Local anesthetic injections placed into an abscess may be ineffective (due to the low pH environment) so more solution than normal may be required. Be careful not to exceed maximum dose. Local injections also risk spreading the infection, so a dental nerve block, procedural sedation, or other anesthesia is preferred. Local infiltrations may be placed in uninfected tissue adjacent to an abscess if needed to supplement a nerve block.

• Do a periapical or panographic x-ray to verify the source of the infection, location and extent of bone destruction, and the type and extent of the abscess.

• Antibiotic prophylaxis for endocarditis should be given to certain high-risk patients prior to drainage of a tooth abscess.

• Microbiologic testing is not usually needed for localized abscesses, but should be done if the patient is immunocompromised, if the infection is recurrent, or if the patient has failed previous surgical/antibiotic therapy.

Abscesses that are drained by intraoral incision include:

• Periodontal abscess originating between the tooth and its gum line, with possible extension into adjacent fascial spaces (eg, vestibular or buccal space)

• Periapical abscess that has spread through the tooth, out the apex, through the surrounding bone, and into the surrounding soft tissues/fascial spaces

• Position the patient inclined, with the patient's head at the level of your elbows and the occiput supported.

• For the lower jaw, use a semi-recumbent sitting position, making the lower occlusal plane roughly parallel to the floor when the mouth is open.

• For the upper jaw, use a more supine position, making the upper occlusal plane roughly 60 to 90 degrees to the floor.

• Turn the head and extend the neck such that the abscess site will be accessible.

• Wear sterile gloves and a mask and safety glasses, or a face shield.

• Retract soft tissues (eg, cheek or tongue) to expose the abscess.

Provide anesthesia

• Use gauze to thoroughly dry the area. Use suction as needed to keep the area dry. Use a cheek or tongue retractor as needed to visualize the area.

• Apply topical anesthetic with cotton-tipped applicators, and wait 2 to 3 minutes for the anesthesia to occur.

• Do a site-appropriate nerve block, but only if the anesthetizing needle will not track the infection into uninfected tissue (refer to How To Do an Inferior Alveolar Nerve Block; How To Do an Infraorbital Nerve Block, Intraoral; How To Do a Mental Nerve Block; or How To Do a Supraperiosteal Infiltration).

• Alternatively (or if the nerve block is not adequate), do local infiltration (field block) around the abscess: Inject 1 to 2 mL into the mucosa anterior and posterior to the abscess, and then at sites along the circumference. Do not pass the needle into any infected tissue.

• Allow sufficient time for anesthetic to take effect (5 to 10 minutes).

• Consider sedation or other anesthesia if needed.

Incise and drain the abscess

• Palpate the abscess to determine its extent and the area where maximum dependent drainage can be obtained.

• Make a 1- to 2-cm incision into the abscess near its most fluctuant point but not into necrotic or friable tissue if possible. Try to enter perpendicular to underlying bone.

• Use suction and gauze squares to remove the exuding pus.

• Insert a hemostat into the full depth of the abscess space. Open the jaws to break up any loculations. Do this in multiple directions to open into the entire space. With each entry, once the jaws are opened, do not close them while in the abscess space, to avoid crushing vital structures and keep the jaws open as you remove the hemostat.

• Copiously irrigate the abscess space with sterile saline using a large syringe with a plastic IV catheter attached. Do not irrigate forcibly; all fluid introduced should be seen to passively flow back out and be suctioned up.

• For larger infections, insert a segment of Penrose drain (1 cm diameter) or a substitute (eg, a cut strip of sterile glove) to the full depth of the abscess space and secure it with a single nonabsorbable suture (eg, 3-0 silk) in healthy tissue near the edge of the incision.

• Patients with diabetes should monitor their blood sugar carefully.

• Encourage patients with significant infection to consume extra fluid and nutrition (ie, to compensate for poor oral intake prior to treatment of the infection and aid healing)

• Arrange dental follow-up in 1 to 2 days, to evaluate the drain for removal.

• A too-small incision will commonly result in tearing of mucosa; err on the side of too long (at least 1 to 2 cm).

• An incision that is not sufficiently deep will hamper effective drainage. In general, incise at least to the depth of the swelling, or down to bone (particularly important for abscesses that have spread by dissecting under the periosteum).

• For an abscess near the infraorbital or mental nerve, place the incision so as to avoid injury to these structures, and dissect carefully.

• If the initial level of anesthesia is suboptimal, preliminary drainage and copious irrigation to remove pus can improve the pH and allow additional local anesthetic to be more effective.