The arrangement, type, and number of teeth which are variously located in the oral or the pharyngeal cavities, or in both. Teeth are found in areas where there is an underlying supporting structure of cartilage or bone and where stomodeal ectoderm is present. The bones with which these structures are usually associated are the mandible (both the cartilaginous bones and the dentary), the premaxillaries, and the maxillaries. However, in certain vertebrates, the vomerine, palatine, parasphenoid, and pterygoid bones may be involved; and in many fishes, teeth are also found on the branchial arches.