Читать книгу Handbook of Oral Pathology and Oral Medicine - S. R. Prabhu - Страница 116

1  2.1 Definition/Description

2  2.2 Frequency

3  2.3 Aetiology/Risk Factors/Pathogenesis

4  2.4 Classification of Caries

5  2.5 Clinical Features

6  2.6 Differential Diagnosis

7  2.7 Diagnosis

8  2.8 Microscopic Features

9  2.9 Management

10  2.10 Prevention

 Dental caries is an infectious, transmissible disease resulting in destruction of tooth structure by acid‐forming bacteria found in dental plaque (an intraoral biofilm) in the presence of fermentable carbohydrates

 The infection results in the loss of tooth minerals that begins with the outer surface of the tooth and can progress through the dentin to the pulp, ultimately compromising the vitality of the tooth

 60–90% of schoolchildren worldwide; the disease is most prevalent in Asian and Latin American countries

 Biofilm acid‐producing bacteria metabolize sugars and produce acids that lower the biofilm pH creating conditions that demineralize tooth enamel and dentin

 Acid‐producing bacteria are Mutans streptococci and Lactobacillus species

 Acids produced include lactic, acetic, formic and propionic acids. These acids are capable of demineralizing enamel and dentin

 Cycles of demineralization and remineralization continue in the mouth in the presence of cariogenic bacteria, fermentable carbohydrates and saliva

 Plaque microorganisms, substrate, susceptible tooth and time are essential factors for the development of caries

 Classification is based on:Rate of progression: acute and chronic cariesAffected dental hard tissues: enamel, dentin and cemental (root surface) cariesLocation on the tooth surface involved: pit and fissure caries, approximal/smooth surface caries and root surface caries (Table 2.1)Table 2.1 American Dental Association caries classification system: Site Definitions‐OriginSource: Based on Ismail, A.I., Tellez, M., Pitts, N.B. et al. (2013). Caries management pathways preserve dental tissues and promote oral health. Community Dentistry and Oral Epidemiology 41 (1): e12–e40.SiteDefinitionPit and fissureThe anatomical pits or fissures (clefts or valleys in the tooth surface) of the teeth at the occlusal, facial or lingual surfaces of posterior teeth OR the lingual surfaces of the maxillary incisors or caninesApproximal surfaceThe contact point(s) between adjacent teethCervical and smooth surfaceThe cervical area or any other smooth enamel surface of the anatomic crown adjacent to an edentulous space (toothless space); may exist anywhere around the full circumference of the toothRootThe root surface apical to the anatomic crown

 Asymptomatic in the initial stages

 Mild pain, tooth sensitivity when carious lesion gets larger

 Visible cavity in the tooth

 Brown, black or white chalky discoloration

 Oral malodour

 Decay at a location that has not previously experienced decay

 Appears at a location with a previous history of caries

 Frequently found on the margins of fillings and other dental restorations

 A lesion on a tooth that was previously demineralized but was remineralized before causing a cavitation

 Severe decay on multiple surfaces of many teeth (Figure 2.1)

 Those at risk: individuals with xerostomia, poor oral hygiene, drug‐induced dry mouth, large sugar intake and radiation to the head and neck region

 Treatment options include therapeutic and preventive strategies, including diet modificationsFigure 2.1 Rampant caries(source: From Mary A. Aubertin. 2014. Common Benign Dental and Periodontal Lesions. In: Diagnosis and Management of Oral Lesions and Conditions: A Resource Handbook for the Clinician, ed. Cesar A. Migliorati and Fotinos S. Panagakos, IntechOpen, doi: 10.5772/57597).

 Rampant dental caries in infants and toddlers; also known as baby‐bottle caries

 Most likely affected teeth: maxillary anterior deciduous teeth (Figure 2.2)

 Cause: allowing children to fall asleep with sweetened liquids in their bottles or feeding children sweetened liquids multiple times during the day

 Education of parents/carers to follow healthy dietary and feeding habits to prevent the development of early childhood caries is important

 Rampant caries often found in methamphetamine users and is often called ‘meth mouth’

 The dental symptoms of methamphetamine users include poor oral hygiene, gingival inflammation, xerostomia, rampant caries and excessive tooth wearFigure 2.2 Early childhood caries(source: by kind permission of Dr Sadashivmurthy Prashanth, JSS Dental College, Mysuru, India).Figure 2.3 Caries in a methamphetamine user(source: From Mary A. Aubertin. 2014. Common Benign Dental and Periodontal Lesions. In: Diagnosis and Management of Oral Lesions and Conditions: A Resource Handbook for the Clinician, ed. Cesar A. Migliorati and Fotinos S. Panagakos, IntechOpen, doi: 10.5772/57597).

 The pattern of caries is distinctive: it tends to start near the gums and involves the buccal smooth surface of the posterior teeth and the interproximal space of the anterior teeth, and progresses to complete destruction of the coronal portion of the tooth (Figure 2.3)

 The key to successful dental treatment is cessation of methamphetamine use.

 Radiation caries is a complication of head and neck cancer radiotherapy

 Typical radiation caries is characterized by enamel erosion and dentin exposure (Figure 2.4)

 Indirect effects of radiotherapy include changes in salivary quantity and composition, together with alteration of the oral flora. These changes are widely regarded as the major causes of radiation cariesFigure 2.4 Radiation caries(source: by kind permission from Dr Vlaho Brailo, School of Dental Medicine, University of Zagreb, Zagreb, Croatia).

 Management of radiation caries includes management of xerostomia and restorative treatment radiation‐induced dental caries. Glass ionomer cements have proved to be a better alternative to composite resins in irradiated patients.

 Hypoplastic enamel

 Hypocalcified enamel

 Fluorosis

 Stains

 History

 Clinical examination: initially a chalky white spot lesion

 Blowing air across the suspected tooth surface is useful

 Later stages cavitation

 Radiography/laser detection

 Early enamel lesion shows:Conical lesion with its apex towards dentinLesion shows four distinct zones of differing translucency (Figure 2.5a and b)Translucent zone (deepest zone)Figure 2.5 (a) Early approximal enamel caries. Undecalcified section of a precavitation stage of enamel caries showing a cone‐shaped carious lesion on the proximal surface of the tooth with its apex towards dentine. The intact surface layer and the body of the lesion are visible. Evidence of early demineralization of dentine is seen beneath the amelodentinal junction deep to the carious enamel lesion. This is due to the diffusion of acids from the enamel lesion into the dentine. The dentine also shows numerous dead tracts. (b) Early pit and fissure enamel caries. Undecalcified section showing precavitation stage of enamel caries surrounding an occlusal pit. The dense surface zone, main body of the lesion, dark zone and peripheral translucent zones are visible.(Source: by kind permission of David Wilson, Adelaide, Australia.)Dark zone (superficial to the translucent zone)Body of the lesion (extends from beneath the surface zone to the dark zone)Surface zoneCaries reaches enamel–dentin junction and spreads laterally, undermining the enamel

 Characteristics of enamel preceding cavitation:Translucent zone:1% mineral lossDark zone:2‐4% mineral loss overall. A zone of remineralization behind the advancing front becomes evidentBody of the lesion:5‐25% mineral lossSurface zone:1% mineral loss

 Dentin caries shows a conical lesion with broad base at the enamel–dentin junction and apex towards pulp

 Bacterial colonies infiltrate dentinal tubules (Figure 2.6 a and b)

 Three zones of dentinal caries seen:zone of demineralizationzone of bacterial penetrationzone of dentine destructionFigure 2.6 Dentine caries. (a) Carious tooth with clinical crown lost to decay. Note bacterial colonies infiltrating dentinal tubules(source: by kind permission of Associate Professor Kelly Magliocca, Department of Pathology and Laboratory Medicine, Winship Cancer Institute at Emory University, Atlanta, GA, USA).(b) Decalcified section showing softened dentinal tubules filled with colonies of bacteria. Multiple clefts caused by spreading infection of dentine are visible(source: by kind permission of David Wilson, Adelaide, Australia).

 Goal: preserve tooth structure and prevent further spread

 Non‐cavitated lesions: arrest of caries by remineralization (optimum oral hygiene and topical fluoride application) and reduction of frequency of refined sugar intake (non‐operative treatment)

 Cavitated lesions: dental restorations with dental amalgam, composite resin, porcelain etc.

 Tooth extraction: non‐restorable carious teeth

 Dental sealants

 Oral hygiene maintenance

 Dietary modification

 Use of fluoridated water (0.7–1.0 ppm) during tooth development periods

 Topical fluoride applications (fluoride toothpaste, varnish, and mouth wash)

1 Featherstone, J.D.B. (2008). Dental caries: a dynamic disease process. Australian Dental Journal 53: 286–293.

2 Machiulskiene, V., Campus, G., Carvalho, J.C. et al. (2020). Terminology of dental caries and dental caries management: consensus report of a workshop organized by ORCA and Cariology research group of IADR. Caries Research 54: 7–14.

3 Major, I. (2005). Clinical diagnosis of recurrent caries. Journal of the American Dental Association 136 (10): 1426–1433.

4 Odell, E.W. (2017). Dental caries. In: Cawson's Essentials of Oral Pthology and Oral Medicine, 9ee (ed. E.W. Odell), 53–70. Edinburgh: Elsevier.

5 Petersen, P.E., Bourgeois, D., Ogawa, H. et al. (2005). The global burden of oral diseases and risks to oral health. Bull World Health Organ 83: 661–669.

6 Philip, N., Suneja, B., and Walsh, L.J. (2018). Ecological approaches to dental caries prevention: paradigm shift or shibboleth? Caries Research 52: 153–165.

7 Pitts, N., Zero, D., and Partnership, C.P. (2012). White Paper on Dental Caries Prevention and Management. A summary of the current evidence and the key issues in controlling this preventable disease. Geneva: FDI World Dental Federation.