Dental and Teeth Facts and Information
Humans usually have 20 primary teeth (also called deciduous, baby, or milk teeth) and 32 permanent teeth.
Among primary teeth, 10 are found in the (upper) maxilla and the other 10 in the (lower) mandible. Teeth are classified as incisors, canines, and molars. In the primary set of teeth, there are two types of incisors, centrals and laterals, and two types of molars, first and second. All primary teeth are replaced with permanent counterparts except for molars, which are replaced by permanent premolars. Among permanent teeth, 16 are found in the maxilla with the other 16 in the mandible.
Third molars are commonly called "wisdom teeth" and may never erupt into the mouth or form at all. If any additional teeth form, for example, fourth and fifth molars, which are rare, they are referred to as supernumerary teeth.
For human teeth to have a healthy oral environment, enamel, dentin, cementum, and the periodontium must all develop during appropriate stages of fetal development. Primary (baby) teeth start to form between the sixth and eighth weeks in utero, and permanent teeth begin to form in the twentieth week in utero.
Enamel is the hardest and most highly mineralized substance of the body and is one of the four major tissues which make up the tooth, along with dentin, cementum, and dental pulp.
Dentin is the substance between enamel or cementum and the pulp chamber. It is secreted by the odontoblasts of the dental pulp.
Cementum is a specialized bony substance covering the root of a tooth. It is approximately 45% inorganic material (mainly hydroxyapatite), 33% organic material (mainly collagen) and 22% water. Cementum is excreted by cementoblasts within the root of the tooth and is thickest at the root apex.
The dental pulp is the central part of the tooth filled with soft connective tissue. This tissue contains blood vessels and nerves that enter the tooth from a hole at the apex of the root.
The gingiva ("gums") is the mucosal tissue that overlays the jaws. There are three different types of epithelium associated with the gingiva: gingival, junctional, and sulcular epithelium. These three types form from a mass of epithelial cells known as the epithelial cuff between the tooth and the mouth.
Most teeth have identifiable features that distinguish them from others. There are several different notation systems to refer to a specific tooth. The three most commons systems are the FDI World Dental Federation notation, the universal numbering system, and Palmer notation method. The FDI system is used worldwide, and the universal is used widely in the United States.
Teething is the process by which an infant's teeth sequentially appear by breaking through the gums. Teething may start as early as three months or as late, in some cases, as twelve months. Occasionally a baby may even have one or more teeth at birth. The typical time frame for new teeth to appear is somewhere between six and nine months.
Tooth Decay
Plaque is a biofilm consisting of large quantities of various bacteria that form on teeth. If not removed regularly, plaque buildup can lead to dental cavities (caries) or periodontal problems such as gingivitis. Given time, plaque can mineralize along the gingiva, forming tartar.
Dental caries, also described as "tooth decay" or "dental cavities", is an infectious disease which damages the structures of teeth.[43] The disease can lead to pain, tooth loss, infection, and, in severe cases, death. In the United States, dental caries is the most common chronic childhood disease, being at least five times more common than asthma.
Cosmetic dentistry
Cosmetic dentistry is very popular today because people the world over are realizing that they can change the way they look and feel relatively easily with the help of a cosmetic dentist. If you were born with unattractive teeth, if they are suffering the affects of aging, or if stress and bad dental care has finally caught up with you, a cosmetic dentist can help turn back the clock with a variety of dental procedures.
When a tooth is lost, dentures, bridges, or implants may be used as replacements. Dentures are usually the least costly whereas implants are usually the most expensive. Dentures may replace complete arches of the mouth or only a partial number of teeth. Bridges replace smaller spaces of missing teeth and use adjacent teeth to support the restoration. Dental implants may be used to replace a single tooth or a series of teeth. Though implants are the most expensive treatment option, they are often the most desirable restoration because of their aesthetics and function.
Discoloration of teeth may result from bacteria stains, tobacco, tea, coffee stains on teeth, foods with an abundance of chlorophyll, restorative materials, and medications. Stains from bacteria may cause colors varying from green to black to orange. Green stains also result from foods with chlorophyll or excessive exposure to copper or nickel. Amalgam, a common dental restorative material, may turn adjacent areas of teeth black or gray.
List of Dental Terms and Definitions
Articles
