Periapical periodontitis


Periapical periodontitis or apical periodontitis is an acute or chronic inflammatory lesion around the apex of a tooth root, most commonly caused by bacterial invasion of the pulp of the tooth. It is a likely outcome of untreated dental caries, and in such cases it can be considered a sequela in the natural history of tooth decay, irreversible pulpitis and pulpal necrosis. Other causes can include occlusal trauma due to 'high spots' after restoration work, extrusion from the tooth of root filling material, or bacterial invasion and infection from the gums. Periapical periodontitis may develop into a periapical abscess, where a collection of pus forms at the end of the root, the consequence of spread of infection from the tooth pulp, or into a periapical cyst, where an epithelial lined, fluid-filled structure forms.
Etymologically, the name refers to inflammation around the root tip or apex of the tooth. 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 or sclerotic changes, or both.

Classification

Classification of periapical periodontitis is usually based on whether the process is acute/symptomatic or chronic/asymptomatic.

Acute periapical periodontitis

Acute periapical periodontitis.

Chronic periapical periodontitis

Chronic periapical periodontitis.

Related lesions

In addition to periapical abscesses, periapical periodontitis can give rise to various related lesions, including periapical granulomas and cysts. A periapical granuloma is a mass of chronically inflamed granulation tissue that forms at the apex of the root of a nonvital tooth.

Treatment

Treatment options may include antibiotic therapy, 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.