Periapical periodontitis or apical periodontitis (AP) is an acute or chronic inflammatory

lesion A lesion is any damage or abnormal change in the tissue of an organism, usually caused by injury or diseases. The term ''Lesion'' is derived from the Latin meaning "injury". Lesions may occur in both plants and animals. Types There is no de ...

around the apex of a tooth root, most commonly caused by

bacteria Bacteria (; : bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of Prokaryote, prokaryotic microorganisms. Typically a few micr ...

invasion An invasion is a Offensive (military), military offensive of combatants of one geopolitics, geopolitical Legal entity, entity, usually in large numbers, entering territory (country subdivision), territory controlled by another similar entity, ...

of the pulp of the tooth. It is a likely outcome of untreated

dental caries Tooth decay, also known as caries,The word 'caries' is a mass noun, and is not a plural of 'carie'.'' is the breakdown of teeth due to acids produced by bacteria. The resulting cavities may be a number of different colors, from yellow to black ...

(tooth decay), and in such cases it can be considered a

sequela A sequela (, ; usually used in the plural, sequelae ) is a pathological condition resulting from a disease, injury, therapy, or other trauma. Derived from the Latin word meaning "sequel", it is used in the medical field to mean a complication or ...

in the

natural history Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...

of tooth decay,

irreversible pulpitis Pulpitis is inflammation of dental pulp tissue. The pulp contains the blood vessels, the nerves, and connective tissue inside a tooth and provides the tooth's blood and nutrients. Pulpitis is mainly caused by bacterial infection which itself is ...

and pulpal necrosis. Other causes can include

occlusal trauma Occlusal trauma is the damage to teeth when an excessive force is acted upon them and they do not align properly.Bibb, CA: Occlusal Evaluation and Therapy in the Management of Periodontal Disease. In Newman, MG; Takei, HH; Carranza, FA; editors: ...

due to 'high spots' after restoration work,

extrusion Extrusion is a process used to create objects of a fixed cross section (geometry), cross-sectional profile by pushing material through a Die (manufacturing), die of the desired cross-section. Its two main advantages over other manufacturing pro ...

from the tooth of root filling material, or bacterial invasion and infection from the

gums The gums or gingiva (: gingivae) consist of the mucosal tissue that lies over the mandible and maxilla inside the mouth. Gum health and disease can have an effect on general health. Structure The gums are part of the soft tissue lining of the ...

. Periapical periodontitis may develop into a

periapical abscess A dental abscess is a localized collection of pus associated with a tooth. The most common type of dental abscess is a periapical abscess, and the second most common is a periodontal abscess. In a periapical abscess, usually the origin is a ...

, where a collection of pus forms at the end of the root, the consequence of spread of infection from the tooth pulp (

odontogenic infection An odontogenic infection is an infection that originates within a tooth or in the closely surrounding tissues. The term is derived from '' odonto-'' (Ancient Greek: , – 'tooth') and '' -genic'' (Ancient Greek: , ; – 'birth'). The most common ...

), or into a

periapical cyst Commonly known as a dental cyst, the periapical cyst is the most common odontogenic cyst. It may develop rapidly from a periapical granuloma, as a consequence of untreated chronic periapical periodontitis. Periapical is defined as "the tissues ...

, where an

epithelial Epithelium or epithelial tissue is a thin, continuous, protective layer of cells with little extracellular matrix. An example is the epidermis, the outermost layer of the skin. Epithelial ( mesothelial) tissues line the outer surfaces of man ...

lined, fluid-filled structure forms. Etymologically, the name refers to inflammation ( Latin, ''-itis'') around (''peri-'' ) the root tip or apex (''-apical'') of the tooth (''-odont-''). Periradicular periodontitis is an alternative term.

Diagnosis

The radiographic features of periapical inflammatory lesions vary depending on the time course of the lesion. Because very early lesions may not show any radiographic changes, diagnosis of these lesions relies solely on the clinical symptoms. More chronic lesions may show lytic (radiolucent) or sclerotic (radiopaque) changes, or both.

Classification

Classification of periapical periodontitis is usually based on whether the process is acute/symptomatic or chronic/asymptomatic. (''Note:'' alternative names for periapical periodontitis include 'apical periodontitis' and 'periradicular periodontitis'.)

Acute periapical periodontitis

Acute (or symptomatic) periapical periodontitis.... Malaise throbbing pain due to Inflammation within periodontal ligament

Chronic periapical periodontitis

Chronic (or asymptomatic) periapical periodontitis.

Related lesions

In addition to

es, periapical periodontitis can give rise to various related lesions, including

periapical granuloma Periapical granuloma, also sometimes referred to as a radicular granuloma or apical granuloma, is an inflammation at the tip of a dead (nonvital) tooth. It is a lesion or mass that typically starts out as an epithelial lined cyst, and undergoes a ...

s and

cysts A cyst is a closed Wikt:sac, sac, having a distinct Cell envelope, envelope and cell division, division compared with the nearby Biological tissue, tissue. Hence, it is a cluster of Cell (biology), cells that have grouped together to form a sac ...

. A periapical granuloma (also referred to as an 'apical granuloma' or 'radicular granuloma') is a mass of chronically inflamed

granulation tissue Granulation tissue is new connective tissue and microscopic blood vessels that form on the surfaces of a wound during the healing process. Granulation tissue typically grows from the base of a wound and is able to fill wounds of almost any size ...

that forms at the apex of the

root In vascular plants, the roots are the plant organ, organs of a plant that are modified to provide anchorage for the plant and take in water and nutrients into the plant body, which allows plants to grow taller and faster. They are most often bel ...

of a nonvital (dead) tooth. (Although not a true

granuloma A granuloma is an aggregation of macrophages (along with other cells) that forms in response to chronic inflammation. This occurs when the immune system attempts to isolate foreign substances that it is otherwise unable to eliminate. Such sub ...

, given the absence of granulomatous inflammation, the term 'periapical granuloma' is widely accepted.)

Treatment

Treatment options may include antibiotic therapy (in the short term, augmented by

chewing gum Chewing gum is a soft, cohesive substance designed to be chewed without being swallowed. Modern chewing gum is composed of gum base, sweeteners, softeners/plasticizers, flavors, colors, and, typically, a hard or powdered polyol coating. Its tex ...

), root canal therapy, or extraction.

Epidemiology

Periapical periodontitis of some form is a very common condition. The prevalence of periapical periodontitis is generally reported to vary according to age group, e.g. 33% in those aged 20–30, 40% in 30- to 40-year-olds, 48% in 40- to 50-year-olds, 57% in 50- to 60-year-olds and 62% in those over the age of 60. Most epidemiologic data has been generated in European countries, especially Scandinavia. While millions of root canal treatments are carried out in the United States alone each year, total numbers of such cases do not provide reliable indicators of frequency, even for symptomatic periapical periodontitis (given that root canal treatment is not always indicated or complied with, and may also be performed in the absence of periapacial periodontitis).

References

External links

{{Oral pathology Periodontal disorders