TDA Online Continuing Dental Education

Exam for Abfraction Lesions - Where Do They Come From? - Exam 43

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Description: The theory of non-carious cervical lesions (NCCLs) suggests that tooth flexure arising from cyclic, eccentric occlusal forces causes their formation and progression in vulnerable cervical regions of teeth. The etiology is still controversial. Attrition, corrosion, abrasion and stress-corrosion might act alone or in combination to initiate and perpetuate lesions. This review of the literature provides the basis for the diagnosis that can be used in consideration of treatment options.

1. Non-carious cervical lesions (NCCLs) are associated with all of the following EXCEPT:

a. Intermittent vertical occlusal loads
b. Tensile forces at or near the cemento-enamel junction (CEJ)
c. Eccentric occlusal loading
d. Flexing stresses throughout the tooth

2. Non-carious carious lesions are more prevalent near the CEJ, on the buccal sides of maxillary premolars because:

a. Cervical enamel exhibits greater porosity
b. There are greater opportunities for remineralization on buccal surfaces
c. The distance between buccal cusps and their centers of resistance are longer than that of lingual cusps
d. Of horizontal tooth brushing

3. All of the following support a greater prevalence of NCCLs among older patients EXCEPT:

a. Multiple missing teeth
b. Diminished quality and buffering capacity of the saliva
c. Heightened incidences of crazing and vertical microfracturing in enamel
d. More frequent tooth brushing with highly abrasive dentifrice

4. Research suggests that eccentric occlusal forces might increase the formation of NCCLs in teeth with coronal cavity preparations by all of the following mechanisms EXCEPT:

a. Changes in the occlusal-cervical width of Class V cavity preparations
b. Cuspal deflection that varies as the square of the length of the cusp in MOD cavity preparations
c. Peak tensile and shear stresses that are greatest near the CEJ
d. A barreling effect during centric loading that results in compression at the CEJ

5. A higher incidence of NCCLs among bruxers is associated with all of the following EXCEPT:

a. Higher eccentric occlusal loading during parafunction
b. Increased total tooth contact time
c. More frequent occlusal contacts
d. Longer contact strokes against cuspal inclines
e. Horizontal forces that induce only compressive stresses in the cervical area