In the maxillae, masticatory pressures on the dental arch are dissipated by being deflected upward over strengthened pillars of bone and around pneumatic cavities. These function in much the same way as does an arch in the wall of a building. Certainly nature's upper facial accommodations for stress distribution equal in beauty and efficiency the Gothic cathedral's, with the additional bonus of serving functions other than mechanical as well.

As a separate entity, the mandible must accommodate masticatory pressures within its body and relay them for dissipation. Thus alveolar trabecular bone is continuous with the cancellous bone that comprises the inner body of the mandible. Below the teeth, the trabeculae unite into a strong trajectory that leads force away from the dental arch. This trajectory, the dental trajectory (1), increases in strength and bulk as it runs posteriorly along the body of the mandible and ascends through the ramus (2) toward the condylar process (3) and the temporomandibular joint. Its strength is quite apparent on the inner surface of the ramus, where it forms a distinct ridge, called the ridge of the mandibular neck (3a).

At the condylar process some of the masticatory forces are transmitted to the base of the skull over the temporomandibular articulation. However, the mere fact that the stresses must pass through a resilient joint also serves to dissipate them. The power of masticatory pressure is amply demonstrated in those individuals who suffer sharp pains, headaches, and other discomforts as a result of temporomandibular joint dysfunction.

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