Which rest type is located at the cingulum or just incisally to it and has a slightly rounded inverted V-shaped form?

Which rest type is located at the cingulum or just incisally to it and has a slightly rounded inverted V-shaped form?

• A. Occlusal rest
• B. Incisal rest
• C. Lug/ball rest
• D. Crescent rest

Answer: (D)

The rest that sits on the lingual surface of an anterior tooth at the cingulum (or just incisally to it) with a slightly rounded inverted V shape is designed to follow the natural contour of the cingulum and provide a stable, compact seat without interfering with the incisal edge or posterior chewing surfaces. This location lets the rest resist anterior-posterior and tipping forces effectively while staying hidden on the tongue side, preserving esthetics and function. The inverted V with a gentle rounding matches the curvature of the cingulum, distributing forces to the abutment tooth without encroaching on adjacent contacts. In contrast, an occlusal rest is placed on posterior occlusal surfaces, an incisal rest sits on the incisal edge, and lug/ball rests have different shapes and placements, so they don’t match the specific cingulum region and the characteristic inverted V form.

The rest that sits on the lingual surface of an anterior tooth at the cingulum (or just incisally to it) with a slightly rounded inverted V shape is designed to follow the natural contour of the cingulum and provide a stable, compact seat without interfering with the incisal edge or posterior chewing surfaces. This location lets the rest resist anterior-posterior and tipping forces effectively while staying hidden on the tongue side, preserving esthetics and function. The inverted V with a gentle rounding matches the curvature of the cingulum, distributing forces to the abutment tooth without encroaching on adjacent contacts. In contrast, an occlusal rest is placed on posterior occlusal surfaces, an incisal rest sits on the incisal edge, and lug/ball rests have different shapes and placements, so they don’t match the specific cingulum region and the characteristic inverted V form.