Periapical pathology l Oral pathology MCQs

 

Periapical pathology ; Acute and chronic apical periodontitis , Acute , chronic and phoenix apical abscess (describing histopathology , radiographically and treatment of each disease) l Oral pathology MCQs for dental students

 

Periradicular Pathology

• Periradicular tissue consists of root cementum, periodontal ligament and the alveolar bone. The apical periodontium is highly cellular structure enriched with blood and lymphatics as well as sensory and motor nerve fiber supplying both pulp and periodontium.

• Periradicular pathology are mostly of pulpal origin. Irritation or injury of the periradicular tissue as a result of bacterial or traumatic insult result in inflammatory response which form the basis of the most of the periodontal pathologies

Periradicular pathology of pulpal infection origin:

1. Acute apical periodontitis
2. Chronic apical periodontitis
3. Acute apical abscess
4. Chronic apical abscess
5. Phoenix abscess
6. Periapical cyst
7. Condensing osteitis

Acute apical periodontitis

• is a localized inflammation of the periodontal ligament in the apical region caused due to irritants of pulpal pathosis diffusing into the periradicular tissue or occlusal trauma.

• It is very painful condition, tooth is tender.

• The tooth remains painful until the bone begins to be resorbed or the fluid is drained, or irritants are removed.

• The irritants such as bacteria, bacterial toxins, disinfecting medications, debris, disintegration products pushed into the periradicular tissues, or traumatic insult of the periapical tissues are the principle culprit for initiating and perpetuating the inflammatory condition.

• The condition is associated with the exudation of plasma and emigration of inflammatory cells from the blood vessels into the periradicular tissues.

• The release of mediators of inflammation leads to breakdown of the periodontal ligament and their action on the nerve fibers in the periradicular tissues partially explain the presence of pain.

• Radiograph may show thickening of the periodontal ligament space. The pulp vitality tests are essential and results must be correlated with other diagnostic information in order to determine if inflammation is of pulpal origin or from occlusal trauma.

Chronic apical periodontitis or chronic periradicular periodontitis

• is a relatively low-grade, longstanding inflammatory response to canal bacteria and irritants. Chronic apical periodontitis is commonly referred to as 'periapical granuloma'.

• The lesion is characterized by a granulomatous tissue with predominance of lymphocytes, plasma cells, and macrophages surrounded by a relatively uninflamed fibrous capsule made up of collagen, fibroblasts, and capillary buds.

• Clinically, this lesion is usually asymptomatic and is revealed radiographically by the presence of an apical radiolucency.

Acute periapical abscess

• It is an acute inflammatory condition of the apical periodontium characterized by localized collection of the pus in a cavity formed by the disintegration of the periradicular tissues.

• The frequent cause of acute apical abscess is a rapid influx of microorganisms, or their products, from the root canal system.

• The tooth is painful and is tender. An obvious intra oral -extraoral swelling may or may not be present.

• The swelling usually remain localized, but may become diffuse and spread widely to other areas. The patient may have fever, and malaise.

• Radiographic features vary from a thickening of the periodontal ligament space to the presence of a frank radiolucency.

• Abscess should be drained by opening the tooth, or in severe cases, through extra or intra oral incision.

• The involved tooth should be tried to be saved through endodontic treatment.

Chronic apical abscess

• is a suppurative inflammatory lesion of long standing due to the chronic proliferative response to low grade periapical infection or trauma.

• Clinically there may be small growth of inflammatory tissue seen in vestibule or gum region and is called a parulis.

• The involved tooth may be tender and painful.

• Microscopic feature includes proliferation of fibroblasts, vascular elements, and the infiltration of macrophages and lymphocytes.

• In addition to the chronic inflammatory response, macrophages and lymphocytes elicit an immune response.

• The purpose of the immune system is to neutralize or destroy a stimulus (antigen or bacteria).

• The treatment is the establishment of drainage and the endodontic treatment of the involved tooth if the tooth is periodontally sound, in other cases involved tooth should be extracted.

Phoenix abscess

• is an acute exacerbation of an existing chronic inflammation. Phoenix abscess result due to an increase in the virulence of the bacteria or decrease in the patient's resistance.

Periapical or periradicular cyst

• Established cystic apical periodontitis: is a direct sequel to chronic apical periodontitis, but not every chronic lesion develops into a cyst.

• Periapical cyst has its origin due to the stimulation and proliferation of the epithelial rests of malassez by  the existing inflammatory condition.

• Periapical cyst is a three-dimensional epithelial lined cavity filled with fluid.

• There are two distinct categories of radicular cysts, namely, those containing cavities completely enclosed in epithelial lining (Bay cyst or apical pocket cyst), and those containing epithelium-lined cavities (true cyst)that are open to the root canals.

Condensing ostitis

• A very low-grade, subclinical response may lead to an increase in the bone density rather than resorption.

• This lesion may be clinically asymptomatic and radio graphically can demonstrate increased trabeculation and opacity.

• Microscopically, dense bone with growth lines is prevalent with a mild chronic inflammatory infiltrate in the marrow spaces.

• The lesion may show regression following endodontic treatment of the diseased tooth.