Tooth strip and periodontal apparatus

The teeth are relatively firmly anchored in the upper jaw by means of the so-called periodontium. In order to be able to fulfil the various protective functions, the periodontium consists of different parts in both the upper and lower jaw. Small but deep indentations within the jawbone (lat.

alveoli) contain the root part of each tooth. In addition, the periodontium consists of the superficial gums (lat. Gingiva propria), the tooth cement (Cementum) and the periodontal membrane (Desmodont or Periodontium).

A closer look at the periodontium quickly reveals that the individual teeth are not absolutely fixed in the jawbone. This would be rather counterproductive considering the forces acting on the teeth during the chewing process. In reality, each individual tooth is suspended in the alveolus by collagen fiber bundles, the so-called Sharpey fibers.

The tooth thus remains relatively mobile and the forces and pressure loads during the chewing process can be effectively distributed over a larger area. The load acting on each individual tooth is thus greatly reduced. Furthermore, the tension of these collagen fibre bundles during the chewing process prevents the roots of the teeth from pressing too deeply into the jawbone under the influence of the pressure.

Origin (embryology)

Historically, there are two parts of the skull, the facial and the cerebral skull. While the brain skull is formed by the bones that form a protective shell around the brain, the facial skull defines the basic features of the human face. The upper jaw, in turn, is a part of this facial skull.

It is in contact with various other bony structures and cavities and for this reason, in addition to its chewing function, it also fulfils a protective function.The upper jaw, for example, forms the floor of the eye socket (lat. Orbita) and thus surrounds the lower part of the eyeball. Furthermore, the upper jaw forms the lateral wall of the nasal cavity (lat.

Cavum nasi) and a large part of the hard palate (lat. Pallatum durum). However, one should not imagine the upper jaw as a compact, dense bone, because it contains one of the largest cavities in the area of the skull, the so-called maxillary sinus (lat.

Sinus maxillaris). During the development of an embryo, six so-called gill arches are formed, which in vertebrates develop from the head intestine. Each of these gill arches has its own gill arches artery, a gill vein, a gill arch nerve and various muscle and cartilage systems.

The upper jaw (lat. Maxilla) itself, just like the lower jaw (lat. Mandibula), develops from the first of these six gill arches.

The so-called mandibular arch is therefore indispensable for the formation of the masticatory organ. In addition, all masticatory muscles, the outer part of the carotid artery (Arteria carotis externa), the maxillary artery (Arteria maxillaris) and the fifth cranial nerve (Nervus trigeminus) develop from the first gill arch. The cartilage of the first jaw arch is used to form both the lower jaw and the upper jaw. In addition, the bony palate is formed from this gill arch, and two of the three ossicles (hammer and ambos, the stapes is formed from the second gill arch).