The orofacial region has a complex anatomy. There are many structures that can cause pain. These include mucosa, soft tissue, muscles, joints, sinuses, blood vessels and viruses. In addition, the region is innervated by several major nerves: the trigeminal, facial, glossopharyngeal and vagus cranial nerves, and the first, second and third cervical spinal nerves. However, by far, the greatest cause of pain in the region is dental in origin (>87%).