Simplex (articulator Gizi), setting of artificial teeth according to Vasiliev

Articulator Is a device that reproduces the movements of the lower jaw relative to the upper jaw in different directions, which is necessary to create multiple correct ratios plastic teeth v prosthesis.

Such devices are divided into 2 groups: simplified and universal. The first group includes the Simplex articulator from Alfred Gizi. However, the setting of the teeth with his device is carried out according to Vasiliev.

How are two surnames related?

Alfred Gizi is the founder of the modern orthopedic dentistry and the classical theory of balancing. Its essence: the movements of the mandibular bone during chewing are cyclical, during the setting of the teeth, it is necessary to maintain contacts between all of them. In 1907 g. he proved that the solution to the problem would be recording the movements of the lower jaw of a particular patient and their technical reproduction.

Gizi believed that the joint directs the movements of the mandibular bone, therefore the devices invented and created by him are called "articular" devices. This is how the Gizi Simplex articulator was created. It belongs to the simplified group.

There were difficulties in the spatial orientation of the models in the device during plastering. The domestic orthopedic dentist, scientist M. Vasiliev proposed a device that solves the problem. This is how the method of setting artificial teeth according to Vasiliev appeared in the Gizi articulator.

Features of devices

Gizi device

The articulator is represented by the upper and lower frames, which are connected at 3 points: in the area of ​​2 articular and 1 incisal areas. They have a slope similar to the incisal and sagittal pathways.

A mobile vertical is installed in the front of the upper frame. pin, which rests against the platform of the lower frame and fixes the height bite. A horizontal pin is attached to it, with its sharp end facing the midline. Together with the protrusions on the lower frame, it forms a triangle with equal sides, inside it and fix the working models.

A horizontal pin is reinforced on the upper frame, its edges are located at the location of the articular heads of the mandibular bone. Due to this, it is possible to displace the frame and recreate movements in the temporomandibular joint and incisor point (that is, imitation of chewing).

The articulator of Gizi belongs to anatomical devices. It regulates the parameters of the articular and incisal pathways, that is, the personal characteristics of movements in the joint of a particular patient are taken into account.

Does not recreate physiological mouth opening. But for prosthetics, this is not significant. Simplex correctly transmits the lateral movements of the jaw, which is the main parameter when chewing and a condition for stabilizing the prosthesis (it cannot be dropped).

Vasiliev's device

The device is represented by a glass plate fixed on a substrate made of gypsum. Its location corresponds to the contact points of the articulator teeth. Mark on the plate: the middle line of the Gizi device and the line where the edges of the upper central incisors.

How the teeth are set

Start

Stages:

• the lower frame of "Simplex" is completely covered with plaster so that there is a gap between it and the edge of the horizontal pin;
• attach several (up to 4) softened sticks from wax;
• attach to them a glass plate in the shape of a trapezoid according to the marks on the articulator;
• cover with plaster the area between the base and the plate, then remove it;
• outside mark the line of the Gizi device and a line perpendicular to it;
• from above, the same plate is fixed with cement;
• go to the next stage.

Plastering models

The model of the maxilla with a wax template is placed on the glass plate of the Vasiliev device, in accordance with the central teeth. The vertical pin is fixed on the incisal platform, and the horizontal one in accordance with the midline of the face.

Plaster the model to the upper frame. Vasiliev's device is removed, the lower model is cast to the lower frame (the marks on the wax templates are connected at the same time).

Fixing landmarks

A trapezoidal plate is placed on the lower bite template. It has a notch for the middle horizontal pin.

The glass is fixed on the template with the maxillary template. Connect the articulator until the wax of the lower bite template is frozen. During this, the vertical pin must abut against the incisor platform. The glass is fixed with heated wax to the lower template. It is removed from the upper model, made anew and proceeds to the setting of the teeth.

Algorithm

Be sure to start with the upper central teeth. They are placed along the midline of the face.

The cutting edges are in contact with the glass. Fangs are set according to the same parameters. When setting the second teeth, the cutting edges should be 0.5-1 mm higher than the glass. The first premolar touches the buccal tubercle, the palatine is located 1 mm higher. The fifth tooth is in contact with both cusps.

First molar: contacts with glass only with the anterior palatine tubercle, the anterior cheek - 0.5 mm higher, the posterior buccal - 1.5 mm, and the posterior palatine - 1 mm. The seventh tooth has no contact with the glass, the posterior tubercles are 2-2.5 mm higher than the glass.

Thanks to this method, occlusal curves are obtained that correspond to the physiology dentoalveolar apparatus. The rules differ for different types of bite and position of the jaws. If necessary, the teeth contacts are corrected to avoid unnecessary ones. If you neglect these rules, the prosthesis will be released when chewing, and the temporomandibular joint will not function properly.