One of the paired elements of the facial part of the skull is the zygomatic bone. It forms a zygomatic arch, which is the border of the fossa of the temple.
Structural features
The zygomatic bone is a quadrangular flat element. It fastens the front (visceral) part of the skull with its brain region. In addition, with its help, the maxillary bone is connected with the sphenoid, temporal and frontal. All this creates a strong support for her.
There are three surfaces that make up the zygomatic bone. Anatomy distinguishes the buccal (lateral), temporal and orbital parts.
The first of them is convex. It with the help of three processes is connected with the maxillary bones, frontal and temporal lobes. The orbital part is involved in the formation of the lateral wall of the orbit and part of its bottom. The temporal is involved in the formation of the wall of the infratemporal fossa, and its plane is turned back.
Zygomatic bone surfaces
The orbital part is smooth, it participates in the formation of the anterior sections of the orbit, namely the part of its outer wall and lower section. Outside, this surface passes into the frontal-main process, and in front of it the infraorbital edge limits. A special cheek-eye hole is placed on it. The orbital surface of the frontal process contains a clearly visible elevation.
The temporal surface is inward and backward. She takes part in the formation of the anterior wall of the fossa of the temple. On it is the zygomatic-temporal opening. The temporal process of the zygomatic bone, extending from its posterior corner, is connected to the zygomatic process of the temporal bone. Together they form a zygomatic arch. Between them is the so-called temporal-zygomatic suture.
Another isolated bone surface is the zygomatic. It is smooth, convex in shape with a special tubercle and cheekbone-facial opening. Its upper semicircular edge is the border of the entrance to the orbit on the side and bottom. The frontal-main process (considered to be part of it) is the upper outer part of the indicated surface. In its front part it is expanded more than in the back. The zygomatic process of the frontal bone is connected with it. Between them is a maxillary suture. It is located on the posterior edge of the upper third of the process, called the frontal.
The zygomatic bone is also bonded to the large wing of the bone, called the sphenoid. Their connection forms a wedge-zygomatic zygomatic suture.
Features
Due to the size of this particular element of the facial skull, its shape and angles that are formed with the front surfaces, determine the
type of physique, gender, race, age.
Experts note 2 stages of development of the zygomatic bone: connective tissue and bone. It is noteworthy that 2-3 sites of ossification appear in the first trimester of pregnancy. They are already at 3 months of fetal development.
It is also noteworthy that through the orbital part of the bone with the help of a thin probe, it is possible to get through the perforating channel into the bones into the cheek-temporal and cheek-facial openings.
Possible injuries
With facial injuries, a fracture of the zygomatic bone cannot be ruled out. It is characterized by deformation and retraction of the corresponding area. In the lower eye area and in the area of the zygomatic arch, the so-called step can be seen. This causes problems when trying to open your mouth or make lateral movements with your
lower jaw. Fractures are also accompanied by retinal hemorrhages and loss of sensation, numbness in the infraorbital nerve.
If the zygomatic bone was displaced significantly, then nosebleeds from a part on the same side and visual impairment are possible, which patients describe as double objects. But an accurate diagnosis can only be made after an X-ray examination.
Treatment methods
If the fact of a fracture of the zygomatic bone was confirmed in the picture, then this means that it is necessary to restore its anatomical integrity. This is done by setting the debris in the correct position. After that, it is still desirable to fix them. If there were no biases, then the treatment is limited to drug therapy and the appointment of physiotherapeutic procedures.
Surgical recovery
Surgery is required only in exceptional cases. These include situations when the zygomatic bone of the skull was fractured, and its processes were displaced.
All surgical interventions can be divided into intraoral and extraoral. The methods of Limberg, Gillies, Dingman are well known. They relate to extraoral methods.
In some cases, its integrity can be restored through an incision in the oral cavity. If the zygomatic bone is fixed using titanium mini-plates, then this gives the most stable results.
After any type of intervention, it is important to avoid the possible displacement of bone fragments. To do this, restrict mouth movements, use liquid and soft foods, and not sleep on the damaged side of the face.
Description of extraoral methods
The Limberg method consists in the fact that through a special puncture (sometimes, however, they make a small cross-shaped incision) in the lower edge of the zygomatic arch, a single-tooth hook is inserted into the cavity. The integrity of the bone is restored by movement, which is done in the direction opposite to the displacement. When it is compared and set to the correct position, a characteristic click is heard. This restores the symmetry of the face. The step that was in the lower edge of the orbit also disappears.
In order to restore the integrity of the surface and replace the temporal process of the zygomatic bone, the Gillies method can be used. The operating doctor makes an incision in the scalp. At the same time, it dissects the skin, subcutaneous tissue and temporal fascia. An elevator is brought through the incision under the zygomatic arch or bone, and a gauze swab is inserted under it. Then, with a special tool that is used as a lever, the fragment is set in the correct position.
According to the Dingman method, a retractor is introduced into the infratemporal fossa through a 1.5-cm incision. Dissection is done in the lateral area of the eyebrow. In this case, after restoring the integrity of the bone surface, the author of the technique recommended applying a wire suture in the region of the lower edge of the orbit, where the frontal process of the zygomatic bone is located.
Intraoral methods
If it is necessary to remove some free-lying bone fragments, blood clots, parts of the mucous membrane, other methods of surgical interventions have been developed. This is possible only during intraoral operations, in which an audit of the maxillary sinus is done.
To restore the integrity of the bones, an incision is made in the region of the transitional fold of the alveolar process. At the same time, the periosteal mucous flap is exfoliated. This is done using a retractor or Buyalsky's scapula, which is carried out under the temporal process of the zygomatic bone.
During this operation, it is also possible to reduce fragments of the bottom of the orbits. For this, an iodoform swab is placed in the corresponding sinus. He must fill it tight in order to keep the bone elements for 10-14 days in the correct position. The end of the indicated swab is displayed in the lower nasal passage. To do this, pre-impose anastomosis.
You can fix the bone plane in the correct position with the help of titanium mini-plates or a wire suture applied in the region of the frontal process, the lower edge of the orbits, the ridge called the cheek-alveolar. But the first method is considered more reliable.
Special cases
In some situations, the use of implants is necessary. They are placed with defects in bone tissue. Doctors often recommend in special cases the use of ceramic implants based on hydroxyapatite in combination with titanium plates.
With appropriate indications, decompression of the infraorbital nerve can be performed. This is done by releasing the intracanal part of it and moving it into orbit. To eliminate bone defects in the alveolar ridge, implants made of titanium nickelide can be used. This requires the restoration of the epithelial lining of the sinuses with flaps from the cheek or graft from the palate. Such tactics can reduce the risk of maxillary sinusitis, which can develop after an injury.
Using external seams, it is possible to fix the zygomatic arch. To do this, sew a plate made of quick-hardening plastic to it. Under it, iodine gauze is necessarily laid. It helps to avoid pressure sores.