Babies have deciduous tooth structures in their jaws that have not yet erupted. Generally, starting from the 6th month, the eruption event begins with the incisor milk teeth. In the baby who is 2 years old, 20 milk teeth are completed in the mouth. At the age of six, the six-year-old tooth, which will remain in the mouth permanently, erupts. From this moment on, the permanent tooth germs, which have completed their preparation in the palate, begin to take their place by melting the roots of the milk teeth. This period is called the mixed dentition period. Usually lasts up to 12 years

Tooth structure: The outermost is hard enamel, the middle is dentin, and the innermost pulp is the pulp. The pulp contains vascular and nerve networks. The root surface of the tooth is called cementum. It is surrounded by gingiva and periodontal tissue.

The tongue is a mobile organ. It allows us to taste the food. During the chewing process, it ensures that the food is taken to the teeth and then to the pharynx. Along with the teeth, it contributes to speech. In the sublingual region, there are rich vascular and nerve networks.

In the mouth, there are salivary gland canals opening into the mouth on the right and left at the level of the upper first molars. In the lower jaw, there are salivary gland duct openings that open into the mouth under the tongue. Thanks to the secretion called saliva, which is secreted from the salivary glands, the food is moistened and made soft and chewing is provided. There are also substances with antibiotic properties in saliva. These provide inactivation of harmful microorganisms for the body. Also, saliva contains enzymes that prepare food to be broken down, so we have to chew food thoroughly and swallow it.

Oral flora is a system that hosts many microorganisms. These microorganisms help to decompose food and protect the oral mucosa. This flora is present from birth.