Читать книгу Anatomy and Embalming - Charles Otto Dhonau - Страница 40

—In the human body we find two sets of teeth. One appearing in childhood, and are known as milk teeth, twenty in number, the permanent teeth replacing these about the sixth year.

There are thirty-two permanent teeth, divided into four incisors, two canines, four bicuspids and six molars.

Teeth are made up of three different substances, which are known as enamel, dentine and cement.

The enamel is a very hard substance, the hardest in the body, and may be compared to quartz. The enamel covers the entire tooth down as far as the gums.

The cement is a continuation of the enamel below the gums, and is closely adherent to the dentine. The cement consists of bone tissue, but the lamellae as a rule do not contain Haversian canals.

The dentine is, next to the enamel, the hardest tissue of the tooth, and composes the main body of the tooth. The pulp cavity is found within the center of the tooth, with the opening toward the jaw bone. The tooth is nourished by a nutrient artery and vein and nerve which pass into the pulp of the tooth.