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How To Drain a Tooth Abscess


Peter J. Heath

, DDS, MD, American Board of Oral and Maxillofacial Surgery

Reviewed/Revised Jul 2022 | Modified Sep 2022

Intraoral incision and drainage of an uncomplicated tooth abscess is done to provide analgesia and limit further and deeper spread of the infection.


  • 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 Pulmonary Embolism (PE) Pulmonary embolism (PE) is the occlusion of pulmonary arteries by thrombi that originate elsewhere, typically in the large veins of the legs or pelvis. Risk factors for pulmonary embolism are... read more Pulmonary Embolism (PE) ) increases the risk of bleeding with dental procedures, but this must be balanced against the increased risk of thrombosis (eg, stroke Overview of Stroke Strokes are a heterogeneous group of disorders involving sudden, focal interruption of cerebral blood flow that causes neurologic deficit. Strokes can be Ischemic (80%), typically resulting... read more Overview of 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

  • Antiseptic oral rinse (eg, chlorhexidine, 0.12%)

  • 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:

  • Topical anesthetic ointment* (eg, lidocaine 5%, benzocaine 20%)

  • Injectable local anesthetic such as lidocaine 2% with or without epinephrine† 1:100,000, or for longer duration anesthesia, bupivacaine 0.5% with or without epinephrine† 1:200,000

  • 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

* CAUTION: All topical anesthetic preparations are absorbed from mucosal surfaces and toxicity may result when dose limits are exceeded. Ointments are easier to control than less-concentrated topical liquids and gels. Excess benzocaine rarely may cause methemoglobinemia.

† Maximum dose of local anesthetics: Lidocaine without epinephrine, 5 mg/kg; lidocaine with epinephrine, 7 mg/kg; bupivacaine, 1.5 mg/kg. NOTE: A 1% solution (of any substance) represents 10 mg/mL (1 gm/100 mL). Epinephrine causes vasoconstriction, which prolongs the anesthetic effect. Patients with cardiac disease should receive only limited amounts of epinephrine (maximum 3.5 mL of solution containing 1:100,000 epinephrine); alternatively, use local anesthetic without epinephrine.

Additional Considerations

Relevant Anatomy

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.

Step-by-Step Description of Procedure

  • 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

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.


  • Instruct the patient to apply warm, moist compresses frequently, take an NSAID (nonsteroidal anti-inflammatory drug, such as ibuprofen 400 mg every 6 hours), and rinse the mouth with warm salt water every 2 to 3 hours for 3 to 5 days (or until follow-up appointment) to stimulate local blood flow and help relieve pain.

  • Patients with diabetes should monitor their blood sugar carefully.

  • Unless the infection was very localized, give an oral antibiotic (eg, amoxicillin 500 mg 3 times a day for 7 days, or clindamycin 300 mg 4 times a day for 7 days).

  • 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.

Warnings and Common Errors

  • 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.

Tricks and Tips

  • 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.

Drugs Mentioned In This Article

Drug Name Select Trade
Betasept, Chlorostat, Hibiclens, Oro Clense , Peridex, Periogard, PerioRx , Perisol
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Ela-Max, GEN7T, Glydo, Gold Bond, LidaMantle, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , Lidomar , Lidomark, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
Advocate Pain Relief Stick, Americaine, Anbesol, Anbesol Baby , Anbesol Jr , Banadyne-3, Benzodent, Benz-O-Sthetic, Boil-Ease, Cepacol Sensations, Chloraseptic, Comfort Caine , Dry Socket Remedy, Freez Eez, Little Remedies for Teethers, Monistat Care, Orabase, OraCoat CankerMelts, Orajel, Orajel Baby, Orajel Denture Plus, Orajel Maximum Strength, Orajel P.M., Orajel Protective, Orajel Severe Pain, Orajel Swabs, Orajel Ultra, Oral Pain Relief , Oticaine , Otocain, Outgro, Pinnacaine, Pro-Caine, RE Benzotic, Topex, Topicale Xtra, Zilactin-B
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Marcaine, Marcaine Spinal, POSIMIR, Sensorcaine, Sensorcaine MPF , Xaracoll
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Midol, Midol Cramps and Body Aches, Motrin, Motrin Children's, Motrin IB, Motrin Infants', Motrin Junior Strength, Motrin Migraine Pain, PediaCare Children's Pain Reliever/Fever Reducer IB, PediaCare Infants' Pain Reliever/Fever Reducer IB, Samson-8
Amoxil, Dispermox, Moxatag, Moxilin , Sumox, Trimox
Cleocin, Cleocin Ovules, Cleocin Pediatric, Cleocin T, CLIN, Clindacin ETZ, Clindacin-P, Clinda-Derm , Clindagel, ClindaMax, ClindaReach, Clindesse, Clindets, Evoclin, PledgaClin, XACIATO
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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