The milk teeth form already in the first year of life. During the growth process, the milk teeth are gradually replaced by the permanent ones.
What are baby teeth?
Schematic diagram showing the anatomy, structure and eruption of milk teeth. Click to enlarge. Because the human jaw is small in size during infancy and toddlerhood, milk teeth are formed first. At the age of about half a year, they start to grow out, which are mostly the central incisors. At the same time, as the child grows, the jaw expands to accommodate the permanent teeth in terms of tooth width and root length. The deciduous teeth usually start to fall out in the sixth year of life and this is caused by the permanent teeth forming behind the roots of the deciduous teeth. This stage of development is called the mixed dentition. By the age of 13, the deciduous dentition has usually been completely replaced by the permanent one. Including the wisdom teeth, which usually erupt from the age of 16, humans have 32 permanent teeth. However, the wisdom teeth do not grow out in everyone.
Anatomy and structure
The primary dentition consists of 20 teeth. Compared to permanent teeth, milk teeth have a thinner enamel layer, which is only one millimeter thick even on the occlusal surfaces. In addition, the mineralization of the enamel is of lower density. Milk teeth have fine, often curved roots, which are dissolved by the permanent teeth during tooth change. The incisors and canines each have one root, while the molars have two in the lower jaw and three in the upper jaw. The pulp of the milk teeth is larger than that of the permanent teeth. The larger dentinal tubules of the dental bone can prove to be disadvantageous, as they provide a better surface for bacteria to attack. Since the hard tissue layer over the pulp is also thinner, it cannot provide adequate protection against bacteria.
Functions and tasks
Deciduous teeth perform a space-keeping function by ensuring that each subsequent permanent tooth has an optimal place in the jaw. If the teeth are lost too early, this function can no longer be performed, which in turn can result in malocclusion. To prevent this, a dental partial denture must be made by a specialist, or a full denture if the milk teeth are completely missing. Furthermore, milk teeth are also of great importance for food intake. In order to avoid problems with biting and chewing, a correct tooth and jaw position is important. If they are not positioned correctly, the mouth may not be able to close properly, which in turn leads to a drying out of saliva and a higher susceptibility to caries. They also play a crucial role in phonation. For example, a prolonged or permanent gap between teeth has negative, lasting effects on the child’s speech. To prevent early loss of milk teeth and malocclusions, early care is important. In infancy, the teeth should be cleaned carefully with a cotton swab every day as soon as they erupt. Up to the second birthday, the teeth must be brushed once a day, then twice a day with special children’s toothbrushes and fluoride-containing pastes. In addition, regular dental checkups should be performed.
Complaints and diseases
Deciduous teeth can also be affected by caries. It can be caused on the one hand by insufficient or incorrect dental care and on the other hand by sugary food or drinks. The main cause of early childhood caries is mostly sugary and acidic drinks, e.g. instant baby teas, teas sweetened with sugar of all kinds or honey, children’s fruit juices, spritzers, iced tea, lemonades, cola, etc. Drinking and sucking on bottles too often can also cause tooth decay. This problem is called “baby bottle caries” and can be recognized by the fact that only the front teeth of the upper jaw are damaged and possibly destroyed. To prevent this type of caries, care should be taken to ensure that the child drinks only when thirsty. In addition, bottles should be replaced by drinking cups from the second year of life. The lactose in human breast milk is a two-fold sugar that is not broken down into glucose until it reaches the small intestine.However, bacteria that lead to caries require simple sugars, such as glucose and fructose, to multiply. So as long as the milk teeth only come into contact with the mother’s milk, there is no risk of caries. Nevertheless, other bacteria also enter the infant’s oral cavity via the mother’s skin and her own hands. Therefore, after breastfeeding, a child-friendly dental cleaning should be carried out. However, tooth decay can attack the teeth through supplementary feeding with baby porridge and other foods and lead to caries in the long term. Especially if brushing is not done after feeding. If a baby tooth is affected by caries, it may not be able to fall out by itself when the tooth changes. The affected tooth must then be extracted. Milk teeth can already cause problems when they grow out. During this process, the tooth has to push through the gum covering, which leads to irritation and slight swelling of the gums. As this reduces the space in the tissue for the nerves, most children feel pain. During this phase, especially infants are very restless.
Typical and common disorders
- Caries
- Early childhood caries
- Toothache
- Jaw misalignment (misalignment of teeth)
- Gum inflammation
