Tooth Wear: Attrition

• Lesions leading to tooth destruction are categorized into carious and non-carious lesions.
• Understanding the etiology and symptoms of these lesions is essential for comprehensive operative treatment.
• Non-carious lesions originate from non-microbial factors, causing defects in tooth structures.

Tooth Wear

• Refers to the wearing away of tooth structure, and includes attrition, abrasion, and erosion.
• It can be caused by natural or unnatural forces, as well as other underlying conditions

Attrition

• Is the mechanical wear of teeth from direct frictional forces between natural contacting teeth.
• A normal physiological process, related to aging.
• Can be accelerated and made more aggressive by parafunctional forces like bruxism and clenching.
• This can result to:
• Flattening of incisal or occlusal surfaces, leading to "wear facet formation."
• Enamel wearing off, with dentin exposure.
• Loss of vertical dimensions of teeth.
• Flattening of proximal contour and decreased mesio-distal tooth dimensions.
• Hypersensitivity and a negative change in appearance.
• Deficient ability to chew and check biting.
• Vulnerability to caries.

Abrasion

• The mechanical loss of tooth structure occurs from direct friction between teeth and external objects.
• Mechanical loss happens due to an abrasive medium that comes into contact with the teeth.
• A pathological and age-dependent process.
• Common types:
• Toothbrush abrasion: Most common, caused by improper brushing.
• It results in localized cervical lesions on labial and buccal tooth surfaces with linear outlines.
• Pipe-smoking depression abrasion: Occurs at the corner of the arch

Erosion

• Erosion constitutes chemo-mechanical loss of a tooth’s structure, mainly due to acids and not due to microorganisms.
• A pathological and age-dependent process.
• Etiology:
• Extrinsic factors: These are usually caused by exposure to environmental acid fumes from battery factories and acidic water in swimming pools.
• Dietary factors: High intake of acidic food and drinks such as lemon juice, grapefruit juice, acidic candies, and carbonated beverages.
• Medications: Low pH medications, such as high uses of Vitamin C “L-ascorbic acid” & acetylsalicylic acid “aspirin”, are potential causes.
• Poor oral hygiene is also can be a contributing factor.
• Intrinsic factors: Gastric acid reaches the oral cavity, such as, frequent vomiting, gastroesophageal reflux, peptic ulcers, or psychological disorders such as stress-induced psychosomatic vomiting, anorexia, and bulimia nervosa, can impact erosion.
• Clinically: Glazed crescent-shaped or dished cervical lesions predominately occur on the face of the teeth with smooth edges and no demarcation.
• Lesions associated with frequent regurgitation occur on the lingual, incisal, and occlusal surfaces.

Abfraction

• A wedge-shaped defect transpires at the neck of the teeth because unbalanced, traumatic occlusal/mastication forces expose at least one tooth to a multitude of tense lateral stresses.
• Micro-fractures form and propagate over time, perpendicular to the long axis of the stresses until cervical enamel and dentin break

Enamel Hypo-calcification

• A defect in enamel resulting from improper matrix mineralization due to injury to ameloblasts, despite well formation of the matrix.
• Affected enamel areas will not be defective and appear as chalky white areas.
• Defects can vary from isolated pits to widespread linear defects or patches.

Enamel Hypoplasia

• Defect in enamel because of improper matrix formation, caused by injuries to ameloblasts.
• This creates defective areas in enamel.
• Commonly seen on anterior teeth and first molars in the form of pitted-and-grooved areas in opaque white or brownish color.

Dental Fluorosis

• The appearance of enamel changes because of fluoride over-consumption during tooth development and presents as both white patches and severe mottled brown teeth.
• Mainly affects permanent teeth.
• Clinical severity hinges of fluoride intake, for both dosage and time.

Discoloration

• A deviation is from the normal tooth shade and color.
• Not a destructive lesion, this affects the individual both socially and psychologically.
• Etiology can be extrinsic or intrinsic:
• Extrinsic: Due to surface staining from food, drinks, smoking, and certain drugs.
• Easy to resolve by cleaning and polishing the teeth through scaling.
• Intrinsic: Created from pathological changes inside teeth tissues and the result of enamel hypoplasia or hypo-calcification.
• Tetracycline staining in pregnant females during tooth formation.

Fracture

• Is a loss of tooth structure from traumatic injuries like a blow or sudden biting on a hard substance.
• Clinical findings will depend on the type of break.
• A simple fracture of enamel (chipping).
• A fracture of enamel and dentin (with or without pulp involvement).
• A total loss of crown structures.
• A fracture of tooth root.
• A total avulsion of the tooth.

Malformation

• A deviation from the normal shape of a tooth.
• Usually occurs due to heredity.
• Shape deviations include micro-dontia or macro-dontia
• The most common type is the peg-shaped lateral incisor tooth which is smaller in size than the surrounding structure.