A periapical abscess may initially be asymptomatic, but in most cases, patients present with intense, throbbing or sharp-shooting pain at the site of the abscess formation. The affected tooth is tender when pressure is applied and chewing on the side where the abscess is formed is usually avoided by the patient because of pain. Intraoral swelling is usually observed on physical examination [6], commonly accompanied with redness of the gums and swelling. In most severe cases, facial asymmetry may be observed because of intense swelling.

Constitutional symptoms, such as fever, malaise, and proximal lymphadenopathy rarely appear and occur in cases of severe inflammation of the tooth and the surrounding structures.

Although very rarely, a periapical abscess may transform into a chronic infection, due to the development of sinus tracts, which serve as channels through which pus is partly drained and can potentially cause complications, such as dissemination of infection to other sites.

• Cervical Lymphadenopathy

  Patients may present with pain, edema, and purulent discharge localized to the site of pathology with or without fever and tender cervical lymphadenopathy 1. [radiopaedia.org]

• Fever

  Perform blood culture in severe cases with signs of systemic infection - both aerobic and anaerobic cultures should be obtained if the patient reports fever. [symptoma.com]

  This occurred in a 78-year-old female patient that presented with general weakness and fever. We revealed that she had a periapical abscess. The blood culture was positive for D. pneumosintes and S. exigua; however, identifying them was challenging. [ncbi.nlm.nih.gov]

  Fever and malaise intensify when the infection penetrates the bone marrow of the jaw, producing osteomyelitis. [healthcentral.com]

  […] odontogenic infection (2% of all apical radiolucencies) Clinical features Severe pain localized swelling and erythematous overlying mucosa Extreme tenderness to persussion and to pressure on chewing Slight extrusion of the tooth non- vital, mobile tooth fever [50roots.blogspot.com]

• Malaise

  Constitutional symptoms, such as fever, malaise, and proximal lymphadenopathy rarely appear and occur in cases of severe inflammation of the tooth and the surrounding structures. [symptoma.com]

  Malaise. Tender lymph nodes. Figure 6-4. - Periapical abscess. [medical.tpub.com]

  • Patient may exhibit raised temperature and malaise. • Fractured and/or discolored tooth crowns/fillings. • The cervical & submandibular lymph nodes tender to palpation. 15. [slideshare.net]

  Cellulitis—spread of infection along fascial planes, breaks through bone; small percentage of patients; Etiology: odontogenic infection, could be trauma or infection elsewhere (rare) Clinical Features: diffuse swelling, tissue is tense, patient looks sick, fever, malaise [oralpathology.blogspot.com]

  Presence of fever and general malaise (feeling poorly) An X-ray image of the tooth may not show changes The patient’s pain is typically relieved to some extent by application of cold substances to the affected tooth, and they often present to the dentist [toothiq.com]

• Chills

  Dental abscesses can also make you generally ill, with nausea, vomiting, fevers, chills, and sweats. [webmd.com]

  If someone develops fever, chills, nausea, or vomiting as a result of a dental abscess, see a doctor. [emedicinehealth.com]

  As the abscess is an acute inflammatory reaction, fever, chills and a general body ache is usually experienced. The lymph nodes on the affected side becomes enlarged and tender in nature. [healthhype.com]

• Sepsis

  Fungal periapical abscesses are a rare and, yet undescribed, potential source of systemic sepsis in the burn intensive care unit. [ncbi.nlm.nih.gov]

  […] infection) are Pain, Swelling, erythema, and Suppuration usually Localized to the affected tooth, even if the abscess can eventually spread causing a severe odontogenic infection which is characterized by local and Systemic involvement culminating in sepsis [gulfdoctor.net]

  You might even develop sepsis — a life-threatening infection that spreads throughout your body. If you have a weakened immune system and you leave a tooth abscess untreated, your risk of a spreading infection increases even more. [mayoclinic.org]

• Fatigue

  The individual may also complain of fever, headache, and general fatigue. An untreated abscess eventually erodes a small channel (sinus) through the jawbone to the surface of the gum. [nmihi.com]

  In more severe cases, when abscesses are large, symptoms such as fever and enlarged lymph nodes may be present, and patients may experience malaise and fatigue. These symptoms indicate that the infection is severer. [symptoma.com]

  […] complications include: Fever Headache Nausea Diarrhoea Swollen lymph glands Pain spreading to the jaw, ear or neck on the same side as the infected tooth Difficulty opening your mouth (trismus) Difficulty breathing or swallowing (dysphagia) General fatigue [dentaly.org]

• Toothache

  When to seek help If you have a toothache or notice evidence of an abscess on your gum, visit your dentist. Even if the abscess drains and the pain decreases, a visit to the dentist for complete treatment is crucial. [ndcs.com.sg]

  Experts say that there are some dental infections that can lead to extremely severe complications if not treated on time and dental abscess is one of them It is said that toothache is one of the most difficult-to-bear pains and as most of us avoid going [timesofindia.indiatimes.com]

  A dental abscess is a collection of pus which can cause toothache and other symptoms. If you suspect that you have a dental abscess, see a dentist as soon as possible for treatment. [patient.info]

• Trismus

  […] have an abscess tenderness of your tooth and surrounding area, especially to touch and on biting, intense, throbbing pain which disturbs sleep sensitivity to food and drink that is very hot or very cold, fever difficulty in opening your mouth (known as trismus [ndcs.com.sg]

  Increased mobility (mostly periapical abscess) Pressure or percussion tenderness (mostly periapical abscess) Extrusion Regional lymph node involvement More severe infection Trismus, indicating involvement of the masticator space Difficulty swallowing [emedicine.medscape.com]

  Inflammatory edema, often complicated by trauma from the opposing tooth, leads to swelling of the flap, pain, tenderness, and a bad taste caused by pus oozing from beneath the flap. 7 Regional lymphadenopathy is common, and cellulitis and trismus (inability [aafp.org]

  […] the mouth More serious symptoms which may indicate dental abscess complications include: Fever Headache Nausea Diarrhoea Swollen lymph glands Pain spreading to the jaw, ear or neck on the same side as the infected tooth Difficulty opening your mouth (trismus [dentaly.org]

• Jaw Pain

  History: 50 year old man with jaw pain. Periapical tooth abscess: Coronal CT image of the face reveals a periapical lucency near one of the right maxillary molars (yellow arrow). [radiologypics.com]

  On Wednesday I had some minor jaw pain in the morning and by 10 PM it looked like I was smuggling a golf ball in my cheek. I had already made an appointment with my dentist and I called my GP and got put on ABX (amoxicillin). [community.babycenter.com]

  Cases in jaws; occurs in mandible bicuspid & molar region - children & young adults. Maxilla is seldom affected, reason not clear. Toothache or jaw pain & bony hard swelling on outer surface of jaw – usually for several weeks duration. [slideshare.net]

• Loose Tooth

  […] as the affected tooth or gum pain that's worse when lying down, which may disturb your sleep redness and swelling in your face a tender, discoloured and/or loose tooth shiny, red and swollen gums sensitivity to hot or cold food and drink bad breath and [nhs.uk]

  Pain, erythema, and swelling Cellulitis Irrigation, antibiotics if cellulitis also present Tooth fracture Broken tooth Clinical examination and radiography Pulpitis and sequelae Fillings, with or without RCT, extraction Tooth luxation Loose tooth Clinical [aafp.org]

• Facial Pain

  Symptoms of sinusitis include: a blocked or runny nose facial pain and tenderness a high temperature (fever) of 38°C (100.4°F) or above Sinusitis often clears up without treatment but, if necessary, antibiotics may be prescribed. [your.md]

  Conditions causing dental pain on first presentation may include pulpitis (reversible or irreversible), periapical periodontitis, dental abscess, as well as cracked tooth syndrome and other oro-facial pain disorders. [nature.com]

• Facial Edema

  If treatment is delayed, the infection may spread through adjacent tissues, causing cellulitis, varying degrees of facial edema, and fever. The infection may spread to osseous (bony) tissues or into the soft tissues of the floor of the mouth. [healthcentral.com]

• Headache

  The individual may also complain of fever, headache, and general fatigue. An untreated abscess eventually erodes a small channel (sinus) through the jawbone to the surface of the gum. [nmihi.com]

  • SYSTEMIC SYMPTOMS: Fever, tiredness, headache, loss of sleep, irritation are present. • Application of ice to some extent relieves pain in contrast to heat which aggravates pain. [endodontics-endodontics.blogspot.com]

  However, pain arising from nondental sources such as myofascial inflammation, migraine headache, maxillary sinusitis, nasal tissues, ears, temporomandibular joints, and neuralgias always must be considered and excluded. 4 CARIOUS ORIGIN Dental caries [aafp.org]

  […] mouth from the infection Swelling and reddening of the face or gums Bleeding from the gums A tooth that is loose and/or discoloured A pea-sized bump inside the mouth More serious symptoms which may indicate dental abscess complications include: Fever Headache [dentaly.org]

• Insomnia

  […] dental abscess include: pain in the affected area when biting or when touching the affected area sensitivity to cold or hot food and liquids a foul taste in the mouth fever a generally unwell feeling difficulties opening the mouth swallowing difficulties insomnia [medicalnewstoday.com]

The diagnosis of periapical abscess can be made on physical examination, by inspection of the oral cavity, and examination of the site where the patient reports pain and swelling. However, the original periapical lesion may not be easy to identify right away, because of possible tissue destruction created by inflammation and infection.

Nevertheless, the diagnosis of periapical abscess should include the following diagnostic steps:

• Evaluate possible underlying risk factor - numerous conditions, as mentioned, predispose patients to development of periapical abscesses, and should be investigated, but primary causes include dental caries and tooth decay.
• Perform a complete blood count, to evaluate the presence of leukocytosis in the blood. Usually, when leukocyte levels are high, the predominant cell type will be neutrophilic.
• Perform blood culture in severe cases with signs of systemic infection - both aerobic and anaerobic cultures should be obtained if the patient reports fever.
• Radiography can help to exclude other localization - it is important to distinguish periapical abscesses from other forms, such as periodontal abscesses, and X rays may initially help in identifying the exact site of lesion.

• Leukocytosis

  […] breaks through bone; small percentage of patients; Etiology: odontogenic infection, could be trauma or infection elsewhere (rare) Clinical Features: diffuse swelling, tissue is tense, patient looks sick, fever, malaise, lethargy, high erythro sed. rate, leukocytosis [oralpathology.blogspot.com]

  Perform a complete blood count, to evaluate the presence of leukocytosis in the blood. Usually, when leukocyte levels are high, the predominant cell type will be neutrophilic. [symptoma.com]

Treatment principles include several approaches:

• Root canal procedure - smaller lesions, as well as localized and uncomplicated periapical abscesses result in infection of the pulp and damage of proximal blood vessels and nerves, which mandates their removal and cleaning. This procedure comprises the removal of the pulp, as well as of infected and damaged structures, abscess drainage and resolution of infection, with appropriate replacement and filling of removed structures. After the procedure, subsequent irrigation with disinfectant material is performed to prevent recurrences.
• Surgical care - in the setting of accumulated pus in the gums and tooth surroundings, surgical incision and drainage is recommended, in order to drain the abscess and pus. In more severe cases, tooth removal may be recommended [7].
• Symptomatic therapy - since patients often present with severe pain, non-steroidal anti-inflammatory drugs (NSAIDs) such as ibuprofen and diclofenac are prescribed to reduce pain, but also because of their anti-inflammatory properties.
• Antibiotic therapy - Treatment of periapical abscesses with antibiotics is usually reserved for larger abscesses [8], and therapeutic choices include metronidazole, clindamycin, and amoxicillin [9].

In most cases, periapical abscesses occur in the setting of a localized infections, and bacteria rarely spread to adjacent structures and distant sites. However, spread of infection to the adjacent bone and sinuses have been observed, as well as dissemination to the central nervous system and other sites through circulation, but these occurrences are quite rare. In terms of the periapical abscesses themselves, those that have extended to the floor of the mouth or to the neck may result in partial airway obstruction, and necessitate prompt treatment, usually through surgical incision, to allow for the pus to be drained.

Periapical abscess is a bacterial infection, and pathogens that have been associated with this infection include Bacteroides spp., Fusobacterium, Actinomyces, Peptostreptococcus, Prevotella oralis and Prevotella melaninogenica, as well as Streptococcus viridans [3]. Most of these organisms are commensal hosts of the oral flora and enter the pulp, leading to the formation of abscesses when the structure of the tooth is breached, which is the case in dental caries, tooth decay, or mechanical trauma. Recent advances in microbiological testing have resulted in the discovery of other pathogens as causative agents of this type of infection, including Treponema spp., Atopobium, Bulleidia extructa, and Mogibacterium species, as well as Cryptobacterium curtum [4]. Up to a third of the microorganisms isolated in these cases produce beta-lactamases, which significantly reduces treatment options.

This form of abscess is most commonly observed in young children, and associated factors include a thinner enamel because of ongoing tooth development, but also poor hygiene, which is still an issue linked to socioeconomic factors, as well as failure to seek dental care. In addition, several developmental and acquired conditions have been linked with periapical abscesses, including abnormal development of the enamel (such as dens invaginatus, or dens evaginatus), as well as dentin malformations, which can be observed in dentine dysplasia, dentinogenesis imperfecta, osteogenesis imperfecta, and familial hypophosphatemia. Acquired conditions may include buccal cysts which become infected [5].

In adults, the formation of periodontal abscesses are much more common than periapical abscess.

The pathogenesis of periapical abscess starts with the formation of dental plaques and erosion of the outer layers of the tooth - the enamel and dentin layers. These two structures protect the tooth pulp from harmful pathogens, and once their structure is breached (as seen in the cases of dental caries or tooth decay), bacteria may enter the pulp, which is supplied with blood vessels and nerves. Once the bacteria reach the local circulatory system, the immune system recognizes the presence of bacteria, and produces an inflammatory reaction, leading to the migration of leukocytes, and production of pre-inflammatory cytokines. All these events lead to pus accumulation and abscesses, which are in this case formed at the apex of the root of the tooth. 

Prevention of periapical abscesses can be achieved through proper dental hygiene, as well as regular dental examinations. Regular teeth cleaning, according to instructions given by the dentist in terms of technique and frequency, as well as other steps involved in dental hygiene should be implemented, and these steps may effectively reduce the risk of any dental disease.

Fluoridation of communal drinking water has been implicated as the most effective large-scale preventive measure against dental caries [10], and the development of other dental diseases including periapical abscesses, while fluoride supplementation is recommended in fluoride-deficient areas. 

Periapical abscess and focal inflammation of the root of the tooth occurs due to penetration of bacteria into the pulp, because of preceding dental caries and plaque formation, which facilitates the entry of bacteria into the soft tissues of the tooth [1]. Once the bacteria penetrate through enamel and dentin, they reach the pulp, which contains blood vessels and nerves; then, they cause an inflammatory reaction, as well as the formation of pus, leading to the development of abscesses [2], which can occur both in the tooth itself, or in the surrounding structures, such as the gums. the term "periapical abscess" implies the formation of this collection of pus at the apex of the root of the tooth.

Patients with periapical abscesses usually present with intense pain, and difficulty in chewing on the side where the abscess is located, while systemic symptoms, such as fever, malaise, and proximal lymphadenopathy occur in more severe cases. With successful treatment, the abscess will resolve, but the underlying dental issues, such as caries and dental decay must be managed properly. If this condition is left untreated, dissemination of bacteria into the surrounding structures, including the proximal bones and sinuses may occur, while dissemination into the central nervous system and distant sites are quite rare. Nevertheless, prompt treatment should be initiated, which comprises root canal procedure, possibly antibiotics, and if necessary, gum resection, to allow for the drainage of pus.

A periapical abscess is a collection of pus in the region of the root of the tooth and the surrounding tissue, caused by a bacterial infection. In most cases, periapical abscessesare formed because the protective structures of the tooth, the crown and the underlying dentin, are damaged because of dental carries, or tooth decay. In this way, bacteria are able to reach the soft tissues of the tooth, the pulp, which is supplied by blood vessels and nerves, and this is the initial site where the bacteria establish an infection. Our immune system recognizes the presence of bacteria, mobilizes white blood cells and releases different enzymes which aid in fighting against the bacteria. As a result of the interaction between the immune system and bacteria, pus is formed, and its accumulation results in  an abscess.

Patients often complain of severe pain in the region of abscess formation, and usually describe it as throbbing and sharp. Swelling of the gums may also be noticed, as well as tenderness of the tooth and the surrounding area, while chewing on the side where the abscess has formed will be rather painful. In more severe cases, when abscesses are large, symptoms such as fever and enlarged lymph nodes may be present, and patients may experience malaise and fatigue. These symptoms indicate that the infection is severer.

A physician, or dentist, may examine the oral cavity and observe the changes in the surrounding regions of the tooth and the state of tissue affected by inflammation. Accompanying tests can include a complete blood count to evaluate signs of possible infection, and an X-ray of the teeth. After evaluation, appropriate therapeutic strategies will be implemented.

Uncomplicated and small abscesses may burst and drain spontaneously, but usually, the recommended treatment is the root canal procedure, which involves complete cleaning of the affected tooth, and removal of inflamed and dead tissue, with subsequent drainage of pus from the tooth canal. After removal of tissue, the tooth will be disinfected, and filled with appropriate material, in order to prevent recurrences. In addition to root canal, surgical incision of the abscess and drainage may be recommended as well, while antibiotic therapy is reserved for patients with severe infections, and those with symptoms such as fever and enlarged lymph nodes. The prognosis is generally good and abscesses may cause no harm if treated promptly and properly, but if left untreated, the infection may spread into the surrounding tissue, such as the bones and the sinuses, or it may gain a chronic course, which can be a debilitating issue for patients and require prolonged treatment and care.

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