D Caries



Introduction
Caries have been a constant nuisance to humans, decaying teeth can become a major problem for those affected. It is certainly not the oldest pathology, nor the one of the greatest prevalence throughout humankind, but the information that can be extrapolate from such pathologies is great. The aim of this paper is to outline the pathology of caries and the influence that these have had on the human populations affected. Caries or caries dentium is the common name for tooth decay. It is a local disease, which is characterized by an irreversible and permanent destruction of the tooth hard tissue, enamel. Thus spreads the destruction to the rest of the tooth and, and possibly leading to tooth loss and possibly infections in other areas, more specifically through the maxillary or mandibular areas.
Also I have included some other defects that are import and not only to the observation of caries but overall pathologies and their implications for the individuals affected. In this paper I will attempt to outline the causes of this disease and some of the numerous factors that cause it, as many have a hand in the process. Also I will show how these changes were brought about and how these affected the individuals with caries.

Systemic Disturbance
To begin I will introduce the reader he to other defects that affect the same area and should be considered when any analysis of the area is to be understood. Any disturbance, such as severe infection can disrupt enamel formation. That disruption of enamel formation will leave an enduring record as a disorientation of enamel prisms. Because the human dental growth sequence is known, the age at which the enamel disturbance occurred can be determined from the location of the disturbance within the enamel. A standard chart for dental development can be consulted for this purpose. There is extensive literature (now in excess of 500 articles) on the epidemiology and etiology of enamel defects. Many of which have been investigations using laboratory animals
There are two types of enamel developmental disturbance of interest to the paleopathologist (1) Microdefects are histological structures known as Wilson bands. These are accentuated brown striae of Retzius. The most celebrated of these is the neontal line, reported by Schour in 1936 If the disturbance is short in duration and the enamel formation resumes, that disturbance is recorded as a narrow band seen in the section of enamel under a light microscope. That evidence of enamel formation disruption and recovery is called a Wilson band. Wilson bands are thin layers of abnormally structured enamel marking the position of the active ameoloblasts at the time of insult. Wilson bands are sometimes called\'pathological brown striae\' in the literature. This descriptive term is a nice way to describe the bands, which contain \'sudden changes in prism direction associated with atypical rod forms.\' Wide neonatal lines are associated with traumatic births. Wilson bands appear to represent brief periods of stress lasting from one to five days.
The examination of teeth for histological disturbance is destructive; therefore, this technique is not used of rare ancient hominid teeth. 2) Macrodefects are defects visible on the tooth surface. They are known as hypoplasias. These can vary in appearance from small pits or furrows to large, deep grooves or even large areas of missing enamel. Typically these defects are horizontal grooves that are called chronological or linear (enamel hypoplasias. They seem to reflect impairment of enamel formation for weeks or months, while Wilson lines record events limited to one or a few days. If the enamel formation does not resume, the defect can be viewed macroscopically as a transverse area of depressed enamel, this is known as enamel hypoplasia, Enamel hypoplasias show a predilection for anterior teeth and for the cervical and middle thirds of tooth crowns. Investigators have shown statistical associations between enamel hypoplasias and a variety of clinical conditions of which we will only mention a few here: premature birth, malnutrition, fluorosis, high fever, localized trauma and systemic metabolic distress such as gastrointestinal disorders.

Dental plaque
Dental plaque is a mixed microbial biofilm growing on teeth and is the prime aetiological agent of the two main oral diseases, dental caries and periodontal disease. The microbial composition of plaque varies between individuals and the location on