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Toothache and Infection


Bernard J. Hennessy

, DDS, Texas A&M University, College of Dentistry

Reviewed/Revised Jan 2024
Topic Resources

Pain in and around the teeth is a common problem, particularly among patients with poor oral hygiene. Pain may be constant, felt after stimulation (eg, heat, cold, sweet food or drink, chewing, brushing), or both.

Etiology of Toothache

The most common causes of toothache (see table ) are

  • Dental caries

  • Pulpitis

  • Periapical abscess

  • Trauma

  • Erupting wisdom tooth (causing pericoronitis)

Toothache is usually caused by dental caries and its consequences.

Caries Caries Caries is tooth decay, commonly called cavities. The symptoms—tender, painful teeth—appear late. Diagnosis is based on inspection, probing of the enamel surface with a fine metal instrument... read more Caries (tooth decay) causes pain when the lesion extends through the enamel into dentin (resulting in sufficient demineralization of tooth structure to cause a cavitation in the outer surface of the tooth enamel). Pain usually occurs after stimulation from cold, heat, sweet food or drink, or brushing; these stimuli cause fluid to move within dentinal tubules to induce a response in the pulp. As long as the discomfort does not persist after the stimulus is removed, the pulp is likely healthy enough to be maintained. This is referred to as normal dentinal sensitivity, reversible pulpalgia, or reversible pulpitis.

Pulpitis Pulpitis Pulpitis is inflammation of the dental pulp resulting from untreated caries, trauma, or multiple restorations. Its principal symptom is pain. Diagnosis is based on clinical findings, and results... read more is inflammation of the pulp, typically due to advancing caries, cumulative minor pulp damage resulting from previous large restorations, a defective restoration, or trauma. It may be reversible or irreversible. Pressure necrosis frequently results from pulpitis. Pain may be spontaneous or in response to stimulation, particularly heat or cold. In both cases, pain lingers for a minute or longer. Once the pulp becomes necrotic, pain ends briefly (hours to weeks). Subsequently, periapical inflammation (apical periodontitis) or an abscess develops.

Periapical abscess may follow untreated caries or pulpitis. The tooth is extremely sensitive to percussion (eg, tapping with a metal dental probe or tongue blade) and chewing. The abscess may point intraorally and eventually drain or may become a cellulitis.

Tooth trauma can damage the pulp. The damage may manifest soon after the injury or up to decades later.

Pericoronitis is inflammation and infection of the tissue between the tooth and its overlying flap of gingiva (operculum). It usually occurs in an erupting wisdom tooth (almost always a lower one).


Rarely, sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Sinusitis results from untreated maxillary dental infection. More commonly, pain resulting from a sinus infection is perceived as originating in the unaffected teeth adjacent to the sinus, mistakenly creating the impression of a dental origin.


Evaluation of Toothache


History of present illness should identify the location and duration of the pain and whether it is constant or present only after stimulation. Specific triggering factors to review include heat, cold, sweet food or drink, chewing, and brushing. Any preceding trauma or dental work should be noted.

Review of systems should seek symptoms of complications, including face pain, swelling, or both (dental abscess, sinusitis); pain below the tongue, difficulty swallowing, and tongue elevation or protrusion (submandibular space infection); pain with bending forward (sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Symptoms include nasal obstruction and congestion, purulent rhinorrhea... read more Sinusitis ); and retro-orbital headache, fever, and vision symptoms (cavernous sinus thrombosis Cavernous Sinus Thrombosis Cavernous sinus thrombosis is a very rare, typically septic thrombosis of the cavernous sinus, usually caused by nasal furuncles or bacterial sinusitis. Symptoms and signs include pain, proptosis... read more ).

Past medical history should note previous dental problems and treatment.

Physical examination

Vital signs are reviewed for fever.

The examination focuses on the face and mouth. The face is inspected for swelling and is palpated for induration and tenderness.

The oral examination includes inspection for gum inflammation and caries and any localized swelling at the base of a tooth that may represent a pointing apical abscess. If no tooth is clearly involved, teeth in the area of pain are percussed for tenderness with a tongue depressor. Also, an ice cube or a dental refrigerant–chilled cotton pellet can be applied briefly to each tooth, removing it immediately once pain is felt. In healthy teeth, the pain stops almost immediately. Pain lingering more than a few seconds indicates pulp damage (eg, irreversible pulpitis Pulpitis Pulpitis is inflammation of the dental pulp resulting from untreated caries, trauma, or multiple restorations. Its principal symptom is pain. Diagnosis is based on clinical findings, and results... read more ). The floor of the mouth is palpated for induration and tenderness, suggesting a deep space infection.

Neurologic examination, concentrating on the cranial nerves, should be done in patients with fever, headache, or facial swelling.

Red flags

Findings of particular concern are

  • Headache

  • Fever

  • Swelling or tenderness of floor of the mouth

  • Cranial nerve abnormalities

Interpretation of findings

Fever is unusual with routine dental infection unless there is significant local extension.

Isolated dental condition: Patients without red flag findings or facial swelling likely have an isolated dental condition, which, although uncomfortable, is not serious. Clinical findings, particularly the nature of the pain, help suggest a cause (see tables and ). Because of its innervation, the pulp can perceive stimuli (eg, heat, cold, sweets) only as pain. An important distinction is whether there is continuous pain or pain only on stimulation and, if pain is only on stimulation, whether the pain lingers after the stimulus is removed.

Swelling at the base of a tooth, on the cheek, or both indicates infection, either cellulitis or abscess. A tender, fluctuant area at the base of a tooth suggests a pointing abscess.



Treatment of Toothache

  • Topical or oral analgesics

  • Sometimes rinses or systemic antibiotics

Analgesics (see Treatment of Pain Treatment of Pain Nonopioid and opioid analgesics are the main drugs used to treat pain. Antidepressants, antiseizure drugs, and other central nervous system (CNS)–active drugs may also be used for chronic or... read more ) may be given pending dental evaluation and definitive treatment. For severe dental pain, local nerve block injections with 0.5% bupivacaine hydrochloride and epinephrine 1:200,000 may relieve pain for many hours until the patient receives definitive dental care. A patient who is seen frequently for emergencies but who never receives definitive dental treatment despite availability may be seeking opioids.

How To Do Dental Nerve Blocks

Antibiotics directed at oral flora are given for most disorders beyond irreversible pulpitis (eg, necrotic pulp, abscess, cellulitis). It is not clear whether antibiotics are beneficial for irreversible pulpitis (1 Treatment reference Pain in and around the teeth is a common problem, particularly among patients with poor oral hygiene. Pain may be constant, felt after stimulation (eg, heat, cold, sweet food or drink, chewing... read more Treatment reference ). Patients with pericoronitis may also receive an antibiotic. However, antibiotics can be deferred if patients can be seen the same day by a dentist, who may be able to treat the infection by removing the source (eg, by extraction, pulpectomy, or curettage). When antibiotics are used, penicillin or amoxicillin is preferred. For patients who are allergic to penicillin, antibiotics such as clindamycin can be used with the warning of the possibility of Clostridioides difficile Clostridioides (formerly Clostridium) difficile–Induced Diarrhea Toxins produced by Clostridioides difficile strains in the gastrointestinal tract cause pseudomembranous colitis, typically after antibiotic use. Symptoms are diarrhea, sometimes bloody... read more –induced diarrhea.

An abscess associated with well-developed (soft) fluctuance is typically drained through an incision with a #15 scalpel blade at the most dependent point of the swelling. A rubber drain, held by a suture, may be placed. (See How To Drain a Tooth Abscess How To Drain a Tooth Abscess 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... read more .)

Pericoronitis or erupting third molars are treated with chlorhexidine 0.12% rinses or hypertonic salt-water soaks (1 tbsp salt mixed in a glass of hot water—no hotter than the coffee or tea a patient normally drinks). The salt water is held in the mouth on the affected side until it cools and then is expectorated and immediately replaced with another mouthful. Three or 4 glasses of salt water a day may control inflammation and pain pending dental evaluation.

Teething pain in young children may be treated with weight-based doses of acetaminophen or ibuprofen. Topical treatments can include chewing hard crackers (eg, biscotti) and chewing on anything cold (eg, gel-containing teething rings). Topical benzocaine can result in methemoglobinemia if used repeatedly or in large amounts and so is usually not recommended.

Treatment reference

  • 1. Fedorowicz Z, van Zuuren EJ, Farman AG, et al: Antibiotic use for irreversible pulpitis. Cochrane Database Syst Rev (12):CD004969, 2013. doi: 10.1002/14651858.CD004969.pub3. Update in: Cochrane Database Syst Rev 2:CD004969, 2016.

Geriatrics Essentials: Toothache

Older patients are more prone to caries of the root surfaces, usually because of gingival recession and medication-induced xerostomia Xerostomia Xerostomia is dry mouth caused by reduced or absent flow of saliva. This condition can result in discomfort, interfere with speech and swallowing, make wearing dentures difficult, cause halitosis... read more . Periodontitis often begins in young adulthood; if untreated, tooth pain and loss are common in old age.

Key Points

  • Most toothache involves dental caries or its complications (eg, pulpitis, abscess).

  • Symptomatic treatment and dental referral are usually adequate.

  • Antibiotics are given if signs of an abscess, necrotic pulp, or more severe conditions are present and if same-day dental care is not available.

  • Very rare but serious complications include extension of dental infection to the floor of the mouth or to the cavernous sinus.

  • Dental infections rarely cause sinusitis, but sinus infection may cause pain perceived as originating in the teeth.

Drugs Mentioned In This Article

Drug Name Select Trade
Marcaine, Marcaine Spinal, POSIMIR, Sensorcaine, Sensorcaine MPF , Xaracoll
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, Epinephrine Professional EMS, Epinephrine Professional with Safety Seal, epinephrinesnap , epinephrinesnap-v, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Amoxil, Dispermox, Moxatag, Moxilin , Sumox, Trimox
Cleocin, Cleocin Ovules, Cleocin Pediatric, Cleocin T, CLIN, Clindacin ETZ, Clindacin PAC, Clindacin-P, Clinda-Derm , Clindagel, ClindaMax, ClindaReach, Clindesse, Clindets, Evoclin, PledgaClin, XACIATO
Betasept, Chlorostat, DYNA-HEX, Hibiclens, Oro Clense , Peridex, Periogard, PerioRx , Perisol
7T Gummy ES, Acephen, Aceta, Actamin, Adult Pain Relief, Anacin Aspirin Free, Aphen, Apra, Children's Acetaminophen, Children's Pain & Fever , Children's Pain Relief, Comtrex Sore Throat Relief, ED-APAP, ElixSure Fever/Pain, Feverall, Genapap, Genebs, Goody's Back & Body Pain, Infantaire, Infants' Acetaminophen, LIQUID PAIN RELIEF, Little Fevers, Little Remedies Infant Fever + Pain Reliever, Mapap, Mapap Arthritis Pain, Mapap Infants, Mapap Junior, M-PAP, Nortemp, Ofirmev, Pain & Fever , Pain and Fever , PAIN RELIEF , PAIN RELIEF Extra Strength, Panadol, PediaCare Children's Fever Reducer/Pain Reliever, PediaCare Children's Smooth Metls Fever Reducer/Pain Reliever, PediaCare Infant's Fever Reducer/Pain Reliever, Pediaphen, PHARBETOL, Plus PHARMA, Q-Pap, Q-Pap Extra Strength, Silapap, Triaminic Fever Reducer and Pain Reliever, Triaminic Infant Fever Reducer and Pain Reliever, Tylenol, Tylenol 8 Hour, Tylenol 8 Hour Arthritis Pain, Tylenol 8 Hour Muscle Aches & Pain, Tylenol Arthritis Pain, Tylenol Children's, Tylenol Children's Pain+Fever, Tylenol CrushableTablet, Tylenol Extra Strength, Tylenol Infants', Tylenol Infants Pain + Fever, Tylenol Junior Strength, Tylenol Pain + Fever, Tylenol Regular Strength, Tylenol Sore Throat, XS No Aspirin, XS Pain Reliever
Advil, Advil Children's, Advil Children's Fever, Advil Infants', Advil Junior Strength, Advil Migraine, Caldolor, Children's Ibuprofen, ElixSure IB, Genpril , Ibren , IBU, Ibupak, 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, Toxicology Saliva Collection
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, HURRICAINE, HURRICAINE ONE, 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
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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