Dental

(den'-tal). Pertaining to the teeth. D. Apparatus, the teeth, together with the alveoli in which they are implanted, and the jaws; also a set of artificial teeth. The instruments and appliances employed in dental operations are likewise so termed. D. Arches, arcades dentaires. The arches formed by the teeth when arranged in their sockets in the alveolar borders, or the arch formed by the alveolar proce of each jaw. D. Arteries, the arteries supplying the teeth. See Arteries, Table of D. Atrophy, atrophia dental is. See Atrophy of the Teeth. D. Bone, dentine. The o eous part of a tooth. D. Canals, the canals that perforate the alveoli, and give pa age to the blood-ve els and nerves that enter the teeth at the extremities of their roots. See Canal . D. Caries, caries of the teeth. D. Cavity, cavitas pulpse; cavum dent is; antrum dentale. The pulp-cavity. The cavity occupied by the dental pulp in the interior of a tooth. Its shape resembles that of the tooth; it is larger in young persons than in old, and when the teeth suffer great lo of substance, either from mechanical or spontaneous abrasion, it sometimes becomes completely obliterated. See Abrasion of the Teeth. D. Engine, a machine first introduced in 1870, but since greatly improved, and which has almost wholly superseded the use of hand-burs and drills. It is operated like a dental lathe, and po e es a flexible cable, or an adjustable arm and hand-piece, which afford great facility of movement and adaptation. By means of attachments to the hand-piece, drills can be operated at a right angle with the shaft, at an acute angle, or with a backward inclination of nearly forty-five degrees. Burnishers, discs, etc., are also adapted to these dental engines. D. Excavator, an instrument employed for the removal of the decayed part of a tooth, preparatory to the operation of filling. D. Exostosis. See Exostosis of the Teeth. D. File, a file manufactured for operations on the teeth. See File , Dental. D. Forceps. See Forceps for Extracting Teeth. D. Glands. See Gland . D. Groove, a furrow on the lower border of the upper jaw early in fetal lite, in which the teeth are developed. D. Laboratory, a room or place where the operations connected with mechanical dentistry are performed. D. Necrosis, odontonecrosis. 'see Necrosis of the Teeth. D. Neuralgia, aform of neuralgia the immediate e