Handbook of Oral Pathology and Oral Medicine. S. R. Prabhu

clefts with multinucleated giant cells, red blood cells, and areas of hemosiderin pigment (Figure 3.2c)Uninflamed layers of fibrous tissue at the peripheryPresence of osteoclasts

       Sequelae of periapical granuloma:Acute exacerbation can cause rapid enlargement of the lesion and may progress to abscess formationProliferation of the epithelial cell rests of Malassez associated with the inflammation may lead to the development of an inflammatory radicular cyst

      3.3.7 Differential Diagnosis

       Cracked‐tooth syndrome and acute periapical abscess to be differentiated from acute apical periodontitis

       Periapical lesions presenting as radiolucent lesions in the apical region of the roots (e.g. periapical cyst, chronic periapical abscess) to be differentiated from periapical granuloma

       Sometimes nasopalatine duct cyst (in maxillary anterior teeth) presents radiographical features mimicking those of periapical granuloma

      3.3.8 Diagnosis

       History

       Clinical examination

       Radiography

      3.3.9 Management

       Apical periodontitis:Identify and eliminate the cause: endodontic therapy is effectiveExtraction of the tooth if exudate is to be drained (apical abscess)Usually, antibiotics are not required for simple (non‐suppurative) cases of periodontitisPain management with analgesics

       Periapical granuloma:Endodontic treatmentExtraction of the tooth if tooth cannot be restored

3.4 Apical Abscess (Dentoalveolar Abscess)

      3.4.1 Definition/Description

      An odontogenic infection characterized by localization of pus in the structures that surround the teeth

      3.4.2 Frequency

       Shows a wide range of variation

       Common in children: accounts for 47% of all dental‐related attendances at paediatric emergency rooms in the United States

      3.4.3 Aetiology/Risk Factors

       Secondary to dental caries, trauma, or failed root canal treatment

       Bacteria and their toxic products enter the periapical tissues via the apical foramen and induce acute inflammation and pus formation

       Polymicrobial odontogenic infection:Anaerobic cocci, Prevotella speciesFusobacterium speciesViridans group streptococci

      3.4.4 Clinical and Radiographical Features

       Non‐vital tooth in most cases

       Involved tooth is tender to percussion

       Lower molars commonly involved

       In the initial stages there is no swelling, only intense, throbbing pain

       Gingiva related to the tooth is red and tender

       In established abscess buccal or labial painful gingival swellings (Figure 3.3a)

       Palatal swelling for maxillary molars is common

       Trismus due to pain and swelling

       Cervical lymphadenopathy is common

       Early dental abscesses, within the first 10 days, may not show any radiographical features

       Mild thickening of apical PDL, loss of lamina dura and loss of trabecular bone become evident as abscess advances (Figure 3.3b)

       Discharge of pus may occur in established abscess; pain subsides after the discharge of pus

       Complications include cellulitis/Ludwig's angina or osteomyelitis

       Life‐threatening complications include thrombophlebitis and septicaemia

       Complete blood count for leucocytosis

      3.4.5 Differential Diagnosis

       Acute periodontitis

       Infected radicular cyst

       Focal sclerosing osteomyelitis

       Periapical granulomaFigure 3.3 Apical abscess. (a) Presenting as a fluctuant gingival swelling; a decayed, broken down tooth with pulpal necrosis has caused this apical (periapical) abscess. Note draining pus via an intraoral sinus(source: Damdent, https://commons.wikimedia.org/wiki/File:Abces_parulique.jpg. Licensed Under CC BY‐SA 3.0.(b) Radiographical appearance of an established periapical abscess. Note the loss of periodontal ligament, lamina dura, and trabecular bone.

      3.4.6 Diagnosis

       History

       Clinical examination

       Radiography (periapical and panoramic views)

       Needle aspirate for aerobic and anaerobic cultures

       Blood culture studies

      3.4.7 Management

       Most dental abscesses respond to incision and drainage, root canal, or extraction. These procedures eliminate the source of infection

       Antibiotics are usually not recommended for localized abscesses

       If drainage is not possible or if the patient shows signs of systemic involvement, or is immunocompromised, antibiotics are required for a period of seven days

3.5 Condensing Osteitis

      3.5.1 Definition/Description

       Condensing osteitis refers to focal areas of bone sclerosis associated with apices of teeth with pulpitis or pulpal necrosis

       Also known as focal sclerosing osteitis and focal sclerosing osteomyelitis

      3.5.2 Frequency

       Occurs in 4–7% of population

      3.5.3 Aetiology

       Low‐grade inflammatory stimulus from an inflamed dental pulp

      3.5.4 Clinical Features

       Most frequently in young adults

       Asymptomatic

       Most lesions are discovered on routine radiography

      3.5.5 Radiographical Features

       Localized increased radiodensity