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

      4.1.5 Differential diagnosis

       Amelogenesis imperfecta

       Dentinogenesis imperfecta

       Tooth defects from trauma

      4.1.6 Diagnosis

       History: diet, habits (clenching/bruxism), use of pipes and smokeless tobacco, tooth‐brushing techniques, regurgitation of gastric contents (bulimia, gastro‐oesophageal reflux disease), etc.

       Clinical examination: location and type of wear facets and tooth defects

      4.1.7 Management

       Attrition: no treatment is required unless symptomatic or aesthetically unpleasant

       Abrasion: restorative treatment for tooth defects to avoid abrasion

       Switch to a minimally abrasive toothpaste

       Erosion: removal of the cause

       Fluoride application for dentinal hypersensitivity and use of a straw for soft drinks

       Medical referral for those with a history of bulimia or gastro‐oesophageal reflux disease

      4.1.8 Prognosis

       Prognosis is good with appropriate restorative treatment

4.2 Pathological Resorption of Teeth

      4.2.1 Definition/Description

       Resorption of teeth:A condition associated with either a physiological or a pathological process resulting in the loss of dentin, cementum, and/or bonePhysiological resorption is a feature of shedding of deciduous teethOnly pathological resorption of permanent teeth is discussed in this chapter

       External resorption:Resorption is initiated in the periodontium and initially affects the external surfaces of the toothExternal resorption may be further classified as surface, inflammatory, or replacement resorption, or by location as cervical, lateral, or apical resorption

       Internal resorption:A defect of the internal aspect of the root following necrosis of odontoblasts because of chronic inflammation and bacterial invasion of the pulp tissue

      4.2.2 Frequency

       External resorption: common

       Internal resorption: rare

      4.2.3 Aetiology/Risk Factors

       Causes of external resorption:Periapical periodontitisImpacted tooth pressing on the root of an adjacent tooth as evidenced on radiographyUnerupted teeth over time may show signs of resorptionReplanted teethPressure from periapical granuloma, cysts or tumoursOrthodontic treatment (common)

       Causes of internal resorption:Unknown (idiopathic)

      4.2.4 Clinical Features

       External resorption:Asymptomatic in most casesLocalized to one tooth or a group of teethMay occur on any surface of the root and occasionally on the crown of an unerupted tooth

       Internal resorption:AsymptomaticClinically, a ‘pink spot’ may be seen at the centre of the crown

      4.2.5 Radiographical features

       External resorption:Apex of the root is shortened (Figure 4.2a)Opening of the apical foramen may be visibleResorbed areas may show irregular marginsRadiodensity of the resorbed area shows variation

       Internal resorption:May be an incidental finding on radiographsRoot canal or pulp chamber shows enlarged radiolucent area (Figure 4.2b)Resorbed area may be symmetrical and the walls may balloon outMargins of the resorbed area are smooth and clearly defined

      4.2.6 Microscopic Features

       External resorption:Numerous multinucleated dentinoclasts near the resorbed surfaceResorbed areas may show deposition of osteodentin (sign of repair)Granulation tissue in large areas of resorption

       Internal resorption:Cellular and vascular fibrous connective tissueMultinucleated dentinoclastsInflammatory cells: lymphocytes, histiocytes and polymorphonuclear leukocytesPresence of woven bone as a sign of repair processFigure 4.2 Resorption. (a) External: cropped orthopantomograph shows external resorption of roots of 47 caused by impacted 48. (b) Internal: radiograph showing radiolucency in the dentinal wall of the pulp chamber of first mandibular molar.(Source: by kind permission of Dr Amar Sholapurkar, James Cook University School of Dentistry, Cairns, Australia.)

      4.2.7 Differential diagnosis

       Carious lesions for internal resorption and periapical lesions for external root resorption should be considered in the differential diagnosis

      4.2.8 Diagnosis

       History of dental procedures (orthodontic treatment in particular)

       Radiography (cone beam computed tomography preferred)

      4.2.9 Management

       External resorption:Identification and elimination of the cause

       Internal resorption:Root canal treatment

      4.2.10 Prognosis

       Good prognosis if the cause has been identified and eliminated and appropriate treatment is carried out

4.3 Hypercementosis

      4.3.1 Definition/Description

       Apposition of excess amounts of normal cementum on the root surface

       Also called cemental hyperplasia

       Two types occur: isolated and diffuse

      4.3.2 Frequency

       The prevalence of hypercementosis is not well established

      4.3.3 Aetiology/Risk Factors

       Isolated (single or a group of teeth) hypercementosis:Most cases are idiopathic and age relatedSome cases show periapical pathosis, parafunctional occlusal trauma, and lack of functional opposition

       Diffuse or generalized (involving all teeth) hypercementosis:May be associated with various syndromes and systemic diseases, such as Paget's disease of bone, acromegaly, thyroid goitre, calcinosis, arthritis, and rheumatic fever

      4.3.4 Clinical Features

       Asymptomatic