Periapical abscess occurs as a result of bacterial infection of the tooth and the surrounding structures, most commonly on the grounds of dental caries and tooth decay. Focal inflammation and abscesses can produce intense pain, and the diagnosis can be achieved through physical examination. Treatment includes antibiotics, root canal procedure, and sometimes resection of the gums to allow for pus drainage.
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 , commonly accompanied with redness of the gums and swelling. In most severe cases, facial asymmetry may be observed because of intense swelling.
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.
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:
Treatment principles include several approaches:
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 . 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 . 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 .
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 , 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 . 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 , 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.