Structure and Functions (Magill’s Medical Guide, Sixth Edition)
Teeth are functional portions of the mouths of animals that assist them in processing food prior to swallowing. This process is called chewing, or mastication. Teeth are also primary offensive and defensive weapons for most animals. Many animals have no hands to grasp or capture food, and their teeth become the principal means of grabbing and killing prey. In humans, teeth not only process food but also have a sociological significance in displaying anger, friendliness, and desirability.
A tooth is composed of three basic parts: the crown, the dental pulp, and the root. The crown of the tooth is that portion exposed above the gingiva, commonly called the gums. The outer surface of the crown is covered by a hard, crystalline substance called enamel. Enamel is an almost completely inorganic material, calcium hydroxyapatite, and it is the hardest tissue in the human body. Underneath the enamel, the bulk of the crown is made up of a substance known as dentin. It, too, is quite hard, but it has more organic material, ground substance and nerve fibers, within it. The dentin is honeycombed by small tubules radiating from the dental pulp chamber at the center of the tooth. These tubules carry nerve fibers from the central nerve within the pulp to the junction of the enamel and dentin.
In the center of the crown is the pulp chamber. The pulp contains nerves and blood vessels that give sensations to and nourish the...
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Disorders and Diseases (Magill’s Medical Guide, Sixth Edition)
The principal scientific professions requiring knowledge of teeth and their surrounding structures are those of dentistry and dental hygiene. Dentists need to have thorough knowledge of the anatomy and physiology of the teeth and their surrounding structures in the mouth. They must be able to detect and treat diseases of the mouth and all its tissues. Dental caries, infected pulp, diseases of the periodontium, and tooth loss are treated by dentists. Dental hygienists aid dentists by treating and identifying diseases of the mouth. Their principal duty is to remove harmful deposits on the teeth, but hygienists also identify diseases of the teeth and periodontium. Using their anatomical and physiological knowledge of the teeth and surrounding structures, hygienists teach patients preventative techniques that can help prevent or halt the spread of dental disease.
Since the teeth and oral tissues are only a part of the body, knowledge of general human anatomy, physiology, and pathology is a must for dentists. Oral symptomatology discovered by dentists is often the first sign of a serious systemic disease. For example, a certain fruity odor on the breath is a sign of ketosis, which is a symptom of diabetes. Kaposi’s sarcoma, a rare type of skin cancer, is often manifested as lesions of the oral tissues; the presence of such lesions may be a strong indication that the patient has acquired immunodeficiency syndrome...
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Perspective and Prospects (Magill’s Medical Guide, Sixth Edition)
Recorded history and archaeological findings show that humans have tried to treat the teeth and their related diseases probably since the Stone Age. There has been speculation among archaeologists that the practice of trepanning, the surgical opening of the skull, could have been in response to severe toothaches as well as other pain in the head. Mutilation of the teeth by the Incas and Mayans was common in noble families; skulls have been discovered in burial sites of both nations showing the insertion of jade disks in slots filed into the front teeth.
In ancient Greece, Hippocrates wrote of treating a severe tumor of the jaw of a young man. After lancing the lesion, he wrote that the condition was morbid and that the young man would surely die. The Greeks also supposed that tooth decay was caused by small worms that bored into the tooth and ate it from within.
In medieval Japan, dentists were trained to extract teeth with their thumb and forefingers. They practiced on tapered wooden pegs pounded into a board. A soft wood was used at first for easier removal, then successively harder boards and pegs were introduced until the dentist could then remove a tooth from the jaw.
Most of the dentistry in the past was surgical removal of painful teeth. From the Middle Ages to the mid-nineteenth century, barbers performed extractions. Without the benefit of anesthetic, this practice was quite painful. Horace...
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For Further Information: (Magill’s Medical Guide, Sixth Edition)
Cook, Allan R., ed. Oral Health Sourcebook: Basic Information About Diseases and Conditions Affecting Oral Health. Detroit, Mich.: Omnigraphics, 1998. This handy reference source, which covers all aspects of dental health, includes helpful statistics on dental disease.
Ferracane, Jack L. “Using Posterior Composites Appropriately.” Journal of the American Dental Association 123 (July, 1992): 53-58. A discussion of the mechanical properties of acrylic composites, including resistance to wear and the use of bonded seals with this restorative material.
Foster, Malcolm S. Protecting Our Children’s Teeth: A Guide to Quality Dental Care from Infancy Through Age Twelve. New York: Insight Books, 1992. This book, meant for parents, is clear and easy to understand. A good starting point.
Langlais, Robert P., and Craig S. Miller. Color Atlas of Common Oral Diseases. 4th ed. Philadelphia: Lippincott Williams & Wilkins, 2009. Provides six hundred color photographs of the most commonly seen oral problems accompanied by descriptive text for each condition.
Parker, James N., and Philip M. Parker, eds. The Official Patient Sourcebook on Tooth Decay. San Diego, Calif.: Icon Health, 2002. Self-described as a reference manual for self-directed patient research, this book describes in clear detail relationships among types of tooth decay and relationships between...
(The entire section is 298 words.)