Introduction
The maxillary sinus (Sinus maxillaris) is the largest paranasal sinus in pairs. It is of very variable shape and size. The floor of the maxillary sinus often shows protrusions, which are caused by the roots of the small and large posterior teeth.
The maxillary sinus is air-filled and lined with ciliated epithelium. There is a small exit to the nose, through which secretion can flow off and air exchange takes place. Due to its location in the upper jaw, it falls within the specialty of the ENT physician as a sinus cavity of the nose. At the same time, however, it also falls into the field of dentistry, since it is located in the upper jaw and is in direct contact with the lateral molars, from which diseases of the maxillary sinus can originate.
Anatomy of the maxillary sinus
The maxillary sinus is the largest sinus of the body. It is arranged in pairs and has the shape of a pyramid, with its base on the side of the nasal cavity and its tip ending towards the zygomatic process. The maxillary sinus is thus located below the eye.
The maxillary sinus is connected to the middle nasal passage via the hiatus semilunaris. The roof of the maxillary sinus is often very thin and also forms the floor of the orbit. The posterior border is pierced by various nerves and blood vessels, which are responsible for the supply of the maxillary sinus, but also of the teeth.
The sensitive innervation of the maxillary sinus takes place via the maxillary nerve. The floor of the maxillary sinus borders on the upper jaw and the hard palate. It also contains the superior dental plexus, a nerve plexus.
The anterior wall is thick and corresponds to the front side of the jaw. The maxillary sinus can be differently developed. In some people it is restricted to the upper jaw bone.
In the case of a pronounced aeration (pneumatization), the maxillary sinus may have various bulges. A distinction is made between the alveolar bay, the zygomatic bay, the infraorbital bay and the palatal bay. The alveolar bay has a spatial relationship with the upper tooth roots.
When removing the upper molars, a connection between the oral cavity and the maxillary sinus can be created. This can lead to germ transfer and inflammation of the maxillary sinus. The maxillary sinus is lined by respiratory ciliated epithelium, which is typical for the respiratory tract.
In 25 to 50% of the maxillary sinus, small partitions can be found pointing towards the palate. These partitions are called Underwood septa. The volume of the maxillary sinus can be up to 15 mL. The growth of the maxillary sinus is completed at the age of 20.
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