A picture shows multiple V-shaped cervical restorations in a patient with bruxism. What is the most likely cause of this pattern?

In a bruxer, excessive occlusal loading creates flexural stress that concentrates at the cervical third of teeth, producing the classic deep, narrow, V-shaped cervical lesions of abfraction. Attrition would show wear on occlusal/incisal contact surfaces (not cervically), abrasion implies a foreign object/habit cause, and erosion has a smooth, shallow, non-V-shaped appearance from acid exposure.