abnormal tooth structure
Introduction
Introduction Refers to the abnormal development of teeth caused by various obstacles during tooth development or matrix calcification during tooth development, and leaves permanent defects or marks on the tooth tissue. Common enamel dysplasia, teeth Insufficient development, dental fluorosis and tetracycline stained teeth.
Cause
Cause
The cause of abnormal tooth structure
The tooth tissue can reflect the past development of the individual. During tooth development, the body's nutrition, metabolism, severe systemic diseases, etc. can affect the developing tooth tissue, causing stunting and leaving permanent defects or traces. Uneven flat sulcus or pit-like defects appear on the surface of the enamel; in severe cases, the cusp or margin is atrophied, the molar or double-toothed surface loses normal fissure morphology, and even some parts of the crown are exposed.
Examine
an examination
Related inspection
Oral endoscopic oral X-ray examination
Examination of abnormal tooth structure
First, enamel hypoplasia (enamel hypoplasia): due to different stages of tooth development, the enamel matrix is blocked when the severity of the formation is different, the time is long, the clinical enamel substantial defects are not the same.
(1) The band shape is due to the enamel development disorder occurring in the same period, and the width of the band reflects the long time of the time of the obstacle. The nest is the destruction of clustered enamel cells, which is called enamel hypoplasia.
(2) The enamel is affected during calcification. The crown has only hardness and color change, the surface is rough white enamel, and there is no substantial defect called calcification.
Clinically divided into mild and severe cases according to the degree of disease:
(1) Mild: The enamel is normal in shape, no substantial defect or obvious horizontal stripes. The enamel is white and opaque, the surface is loose and rough, the permeability is high, and the external pigmentation is yellowish brown.
(2) Severe: The enamel of the tooth surface has a substantial defect, which is a band or a hollow. In severe cases, the entire tooth surface is honeycomb-shaped or even enamel-free.
Chronic apical periodontitis infection of the deciduous teeth causes enamel hypoplasia of the bicuspid teeth. Because most of the enamel is defective, it is easily mistaken for the root of the deciduous teeth and is removed. Therefore, it is carefully identified according to age and morphology.
Second, dentin hypoplasia: is a disease characterized by chromosomal dominant or invisible inheritance.
Type I dentine hypoplasia, accompanied by bone tissue dysplasia.
Type II dentin hypoplasia, simple dentin dysplasia, no other organ abnormalities, also known as hereditary opalescent dentin.
Diagnosis
Differential diagnosis
Symptoms of abnormal tooth structure
Abnormal tooth size:
Oversized teeth, also known as giant teeth. Giant teeth are often accompanied by insufficient number of teeth. In the early stage of tooth germ formation, two adjacent tooth germs are squeezed by external force to fuse into a giant tooth. The hyperfunction of the pituitary gland can also cause huge deformity of the teeth, which is seen in acromegaly. patient.
Too small teeth, seen in individual teeth, such as the maxillary incisor, the second double canine, the third molar. These teeth are considered to be a manifestation of degeneration of the chewing organs. Dwarf of the whole mouth is seen in the spleen of hypothyroidism and dwarfism in which the pituitary thyroid hormone is insufficiently secreted. In addition, ectodermal dysplasia or congenital children often have small teeth.
Abnormal tooth nodules or annulus: The central tip is the excessive growth of the central nodule of the premolar, forming a cusp that is higher than the occlusal surface. Because the central tip of the deformity is related to ethnic inheritance, it is only found in the ethnic groups of the East, such as China, Japan, the Philippines, and other Mongolian pedigrees.
Fusion teeth: often due to the fusion of two normal embryos, this fusion can be complete or incomplete during tooth development. The cause of fusion is generally thought to be caused by stress, when mechanical pressure causes the two developing tooth germs to squeeze together and gradually fuse. If the pressure occurs before the calcification of the two teeth, a fully fused giant tooth is formed. If the pressure occurs after the development of the crown is completed, the root fusion is formed into one, and the crown is divided into two. Sometimes only part of the dentin, enamel fusion, the root canal can be one or two. In deciduous teeth, especially the anterior teeth of the anterior teeth are most common.
During the development of the tooth, the glazed indentation indents a tooth germ that is not completely separated, forming a crown that is completely or not completely separated, and has a common root, which is also called a twin tooth.
Fusion teeth are often accompanied by a reduction in the number of teeth. There are reports in the literature that fusion teeth have a genetic predisposition.
Abnormal pulp cavity: the pulp cavity is very large, especially the long axis of the medullary cavity is very long, and the root is very short. This type of tooth is called a bovine tooth, because it is found in the teeth of herbivores such as cattle. These features are named.
Incomplete tooth formation: The teeth are divided into two steps: tooth matrix formation and calcium salt deposition. If the dental cells are damaged, the deposition of calcium salts and the formation of the matrix are also affected, and the formation of the teeth is incomplete.
