Final answer:
The area where adjacent teeth touch each other on their proximal surfaces is called the contact area. This area is important for maintaining tooth alignment, chewing function, and preventing food impaction.
Step-by-step explanation:
The area on proximal surfaces where adjacent teeth in the arch touch each other is called the contact area. This region is crucial as it maintains the position of the teeth within the arch, supports proper chewing function, and helps protect against food impaction. The teeth are supported by structures like the alveolar processes, and are held in place by the periodontal ligament, which also plays a role in the structural integrity and positioning of the teeth.