The formation process and the formation of the teeth is called Odontogenesis designated. More precisely, it is understood to mean the period in which the first appendages of the milk teeth are formed and the teeth of the permanent dentition erupt, including the development of the tooth ridge, the formation of tooth enamel, tooth crown, root and the entire tooth bed in the tooth support apparatus.
The formation process and the formation of the teeth is called odontogenesis.
Odontogenesis begins around forty days after ovulation, while the fetus is a few eight millimeters long. The development of teeth as a process is very complex. The tooth system forms the preliminary stage of the tooth with the tooth bell. A natural oral space is created.
Tooth enamel, root element, dentin and periodontal membrane develop during embryogenesis. The distinction between the tooth structures begins between the fifth and eighth week of pregnancy. They are divided into the tooth bar, knot, cap and bell stage, each of which has different processes of tooth development.
First, in the oral cavity of the fetus, the tooth strip grows from the inner layer of the ectoderm, which then extends into the middle layer that forms the jaw. Thickenings form on this layer, which prepare the actual milk teeth. Enamel caps arise from tooth buds, which in turn form dental papillae. The whole process leaves behind the construct of the enamel organ, which is initially cap-shaped in its shape and finally resembles a bell.
The tooth bud fulfills important functions, which include the dental papilla, the dental follicles and the enamel organ and consists of a collection of cells. In the dental papilla, cells are converted into odontoblasts, which later form dentin. The connection between the inner tooth epithelium and the dental papilla determines the overall shape of the tooth crown. Mesenchymal cells, in turn, are responsible for the formation of the tooth pulp.
The tooth follicles are also called tooth sacs. They prepare the tissue for the osteoblasts, centoblasts and fibroblasts, while the latter form the periodontal ligaments that connect the tooth to the tooth socket through a root element. This is where the various phases of tooth development take place, from the bud to the crown stage.
While the tooth system is being formed, the hard tooth tissue, also known as hard tooth substance, is also formed. This means the tooth crown, which consists of tooth enamel and dentin. The formation of tooth enamel is called amelogenesis in dentistry and takes place during the crown stage. Ameloblasts are responsible for the transport of certain proteins to produce tooth enamel.
Dentin is tissue that is similar to bone and is softer than tooth enamel. The development is called dentinogenesis and goes through three phases. During tooth formation, primary dentin is produced, then secondary dentin is produced by the tooth pulp and, through synthesis and subsequent reduction in size of the tooth pulp, irritant dentin.
The tooth bell is now delimited from the outside during the entire process. This happens through the outer enamel epithelium, while the highly prismatic inner enamel epithelium fills the inner surface. The latter faces the dental papilla and emerged from the mesenchyme. The enamel pulp lies between the inner and outer enamel epithelium.
Finally, towards the end of odontogenesis, the root element emerges, known as cementogenesis in dentistry, as the cells form cementoblasts. There are still many unanswered questions about the formation of the gums. It is known that the cells are anchored there by fiber-like structures that are the remains of the ameloblasts. The layer grows very quickly through cell division.
Tooth eruption occurs as a result of the increasing growth pressure in the process of odontogenesis and the slow advancement of the milk teeth. The process is known as teething and is very painful. Side effects are redness, swelling and slight infections, which can be associated with an increased body temperature.
Teething occurs as soon as the first teeth emerge in the baby's mouth and the mucous membrane overlying the teeth thins to reveal the tooth. When the tooth eruption takes place differs from person to person. It can take place early, but also late. It usually begins as soon as the milk teeth are fully developed. This is the case after about eight months. First the incisors grow, then the first molar, the canine and finally the second molar.
In the finished state, the milk teeth form the first set of teeth, followed by the failure of the milk teeth, the second and permanent set of teeth. This usually happens between the age of seven and nine, starting with the loss of the rear molars, and finally the central and lateral incisors. Finally, the front molars and canines are replaced with new teeth.
Some difficulties can arise during odontogenesis, which can lead to dental diseases. A late eruption is not one of them. However, z. B. form additional molars, associated with a developmental disorder of the tooth tissue.
In dentistry, a distinction is made between congenital and acquired disorders. Congenital can z. B. in the number of teeth, but also in the shape and size of the teeth. Due to a genetic defect, the enamel coating as a tooth coating can be completely missing. Dysodontia can also occur, which is understood to be a malformation of the tooth system. Acquired changes, however, occur through infections, injuries or z. B. rickets.
There are also misaligned teeth that result from a combination of acquired and congenital causes. This includes crowded teeth, whereby individual teeth are tilted or twisted and in some cases can even break out of the dental arch because the teeth have too little space in the jaw.