Abfraaktio

Abfraaktio, commonly known in English as abfraction, refers to a proposed mechanism of tooth structure loss at the cervical region of a tooth. It describes wedge-shaped non-carious cervical lesions believed to result from stresses and flexure of the tooth under occlusal loading, rather than from decay or direct surface contact alone.

Mechanism: Concentrated tensile stresses at the cervical area arise during biting or grinding, especially under lateral movements or bruxism. These stresses may cause microfractures in enamel and dentin and progressive loss of tooth structure at the cementoenamel junction. Lesions are typically wedge-shaped with the apex at the CEJ. The abfraction concept has been debated, and many clinicians view NCCLs as multifactorial, involving abrasion and erosion in addition to occlusal stress.

Diagnosis and clinical features: Diagnosis is clinical: lesions near the gingival margin, often asymptomatic, though some patients report sensitivity. Radiographs rarely show the defect. Differential diagnosis includes abrasion from toothbrushing, attrition from wear, erosion from chemical exposure, and caries in atypical locations.

Treatment and management: Management aims to address contributing factors and restore function and aesthetics when needed. This may involve occlusal analysis and stabilization (night guard or bite adjustment), restorative approaches with composite or porcelain veneers when indicated, and preventive counseling. Prognosis varies with lesion size, activity, and control of contributing factors.

History and terminology: The term abfraaktio reflects the historical concept that occlusal stress causes cervical lesions. The concept emerged in the late 20th century and remains controversial; current views emphasize multifactorial etiologies and individualized treatment plans.