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. Investigator...