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

      3.2.4 Clinical and Radiographical Features

       Reversible pulpitis:Pain from cold test does not linger for longer than 30 secondsNo percussion sensitivityNo spontaneous painNo heat sensitivity

       Irreversible pulpitis:Pain from cold test lingers for longer than 30 secondsMay get pain from heat testMay have spontaneous painMay be percussion sensitiveSleep or work is affectedA patient may have difficulty locating the tooth from which the pain originatesRadiographically or clinically, deep caries may be visible

       Chronic hyperplastic pulpitis:Presence of a pink fleshy mass filling a carious cavity (pulp polyp; Figure 3.1)Usually single, rarely involving multiple teethNon‐tender or mildly tenderBleeds readily on probing

      3.2.5 Microscopic Features

       Acute pulpitis:Pulpal hyperaemiaFocus of acute inflammatory cell infiltrateFigure 3.1 Chronic hyperplastic pulpitis (pulp polyp) presenting as a fleshy mass in the carious cavity (white arrow).Destruction of odontoblastsFormation of an abscess in some cases

       Chronic pulpitis:Mononuclear cell infiltrate (chronic inflammatory cells)Focus of pulp necrosisAbscesses and pus formationWall of granulation tissue

       Chronic hyperplastic pulpitis:Mass composed of granulation tissueRich vasculatureChronic inflammatory cell infiltrateStratified squamous epithelial lining covers the surface of granulation tissue

      3.2.6 Differential Diagnosis

       Periodontal pain

       Dentin hypersensitivity

       Cracked tooth syndrome

       Dental trauma

       Idiopathic orofacial pain

       Pain from restorative procedures

       Pain of non‐odontogenic origin

      3.2.7 Diagnosis

       Based on history, clinical examination and testing

       Radiography detects carious lesions causing pulpitis

       Thermal tests

       Radiographical examination for clinically visible and non‐visible caries and for recurrent carries under restorations, lamina dura and periodontal ligament (PDL) space

      3.2.8 Management

      3.2.8.1 Reversible Pulpitis

       Remove the irritant or repair tooth structure (caries, exposed dentin, defective restoration)

       Continue to monitor the patient's symptoms

       Advise patient to return if symptoms persist or worsen

       Pain management with analgesics (ibuprofen and paracetamol)

       Antibiotics are not required

      3.2.8.2 Irreversible Pulpitis

       Pulpectomy of the offending tooth: complete removal of the pulp

       Root canal treatment

       Pain management with analgesics

       Antibiotics are not recommended

       Extraction if tooth cannot be saved

      3.2.8.3 Chronic Hyperplastic Pulpitis

       Extraction of the tooth

3.3 Apical Periodontitis and Periapical Granuloma

      3.3.1 Definition/Description

       Apical periodontitis refers to inflammation of the PDL surrounding the apex of the tooth caused by infection, bacterial products, or other irritants through the apex of the root. Usually, this occurs due to acute inflammation (acute apical periodontitis)

       Periapical granuloma, also known as chronic apical periodontitis, refers to formation of granulation tissue surrounding the apex of a non‐vital tooth arising in response to pulpal necrosis

      3.3.2 Frequency

       Prevalence of apical periodontitis shows variation

       Prevalence increases with age; by 50 years of age, one in two individuals will experience apical periodontitis

       In individuals over 60 years of age, the prevalence rises to 62%

      3.3.3 Aetiology/Risk Factors

       Bacterial invasion from the pulp

       Occlusal trauma from the high spots of restorations

       Irritants and inflammatory mediators from the necrotic pulp

       Endodontic procedures (iatrogenic)

       Gingival infection

      3.3.4 Clinical Features

       Apical periodontitis:Acute form is commonPain and tenderness of the tooth on slight touchMinutely extruded toothNo changes with hot and cold drinks or foodSequelae: may proceed to dental abscess or chronic apical periodontitis

       Periapical granuloma:Most cases are asymptomaticTooth involved is non‐vitalTooth is slightly tender to percussion

      3.3.5 Radiographical Features

       Apical periodontitis:Usually, no significant changes seenOccasionally, lamina dura may show haziness or slightly wide periodontal space

       Periapical granuloma:Presents as a radiolucent lesionA radiolucent lesion of a few millimetres in size is usually indistinguishable from a periapical cystAn affected tooth typically reveals loss of the apical lamina duraRoot resorption is not uncommonA radiolucent lesion associated with the root apex often has fuzzy borders (Figure 3.2a)Figure 3.2 Periapical granuloma. (a) Radiolucent lesion of periapical granuloma at the root apex of the non‐vital lateral incisor. (b) Photomicrograph showing apical connective tissue (black star) with chronic inflammatory cells and proliferating epithelial cells. Microscopic features demonstrate an evolving periapical cyst arising from periapical granuloma(source: by kind permission of Associate Professor Kelly Magliocca, Department of Pathology and Laboratory Medicine, Winship Cancer Institute at Emory University, Atlanta, GA, USA).(c) This photomicrograph shows cholesterol clefts and multinucleated giant cells in a mature periapical granuloma. These features are similar to those of periapical cyst.

      3.3.6 Microscopic Features

       Apical periodontitis:Engorged blood vesselsIntense infiltration of neutrophils

       Periapical granuloma:Chronically inflamed granulation tissue around apex of a non‐vital tooth shows:Lymphocytes, macrophages, and plasma cells intermixed with neutrophils and proliferating epithelial cells (cell rests of Malassez) within the granulation tissue (Figure