WO2012112069A1

WO2012112069A1 - Method for locating a patient's mandible head axis

Info

Publication number: WO2012112069A1
Application number: PCT/RU2011/000849
Authority: WO
Inventors: Евгений Михайлович РОЩИН; Валентин Дмитриевич ПАНТЕЛЕЕВ; Александра Владимировна РОЩИНА
Original assignee: Roschin Evgeniy Mikhailovich; Panteleev Vanlentin Dmitrievich; Roschina Aleksandra Vladimirovna
Priority date: 2011-02-18
Filing date: 2011-11-02
Publication date: 2012-08-23
Also published as: RU2454180C1

Abstract

The invention relates to medicine. The method for locating a patient's mandible head axis consists in specifying dermal points made of an X-ray contrast substance or material on a patient's skin and subsequently taking a computer tomogram in a lateral projection reflecting the above-mentioned points, and drawing, on the computer tomogram, a first line from the upper edge of the acoustic meatus to a point corresponding to the lower edge of the eye socket, from said line drawing a perpendicular line downwards passing tangentially along the rear convex edge of the articular mandible head, then drawing a perpendicular line downwards passing tangentially along the front convex edge of the articular mandible head, and a lower line passing through the neck of the joint, said line being parallel to the first line, determining a point within the outlined zone, which point is the patient's mandible head axis, and the coordinates of said point in relation to the projections of the dermal points on said X-ray photograph, and then transferring the projection of the point of the patient's mandible head axis on said X-ray photograph to the patient's skin in the area of the dermal points applied earlier.

Description

The method of finding the axis of the head of the lower jaw of the patient

Technical field

The invention relates to medicine, namely to diagnostics in dentistry to determine the area of placement of the axis of the head of the lower jaw of the patient. State of the art

Muscular-articular dysfunctions cause patients discomfort in the maxillofacial region and facial pain. The cause of these complaints is in many cases occlusion disorders. The basis for the diagnosis of such disorders is a functional analysis of the dentition, the main purpose of which is to establish a relationship of violations). According to the articulation of the lower jaw with the pathology of occlusion of the dentition, masticatory muscles and temporomandibular joint (TMJ), V.A. Khvatova believes that muscular-articular dysfunctions in case of occlusal disorders can be represented as follows. Due to the altered muscle function, the movements of the lower jaw are carried out in such a way as to avoid occlusal obstacles. There is an asymmetry of muscle activity and topography of the temporomandibular head, trauma to the nerve endings of the joint capsule, appendage zone, and a violation of the hemodynamics of the TMJ tissue. Thus, of particular importance in the diagnosis of muscular-articular dysfunctions is the determination of the topography of the TMJ heads, in particular the determination of the location of the axis of the head of the lower jaw of the patient.

Known clinical and laboratory research methods, such as palpation of TMJ, the nature of mouth opening, assessment of occlusion, occlusion, identification and characterization of supercontacts, functional tests, analysis of jaw models and so on give indirect information about the topography of the TMJ heads.

Known instrumental methods for visualizing the TMJ, such as X-ray and magnetic resonance imaging of the temporomandibular joint region (V.A. Khvatova "Diagnosis and treatment of functional occlusion disorders" Guide. Publishing house of the NMD, N-Novgorod, 1996, p. 68-77).

The x-ray method is an important part of the analysis of the dentition. However, survey radiographs are of little use for functional analysis, since the joint gap is not visible throughout, there are projection distortions, overlays of the surrounding bone tissue.

Known methods (such as radiography and magnetic resonance imaging of the TMJ region) allow the joint itself to be visualized with greater or less certainty, but it is not possible to accurately determine the position of the actual axis of the head of the lower jaw of the patient.

A known method of finding the axis of the head of the lower jaw by setting the calculated point in front of the ear of the patient, which will display the axis of the head of the lower jaw on the skin of the patient. (GROSS M. D., MATEWS J. D. "Normalization of occlusion", M, "Medicine", 1986, p. 148, 149, translated from English GROSS M. D., MATHEWS JD "Occlusion in Restorative Dentistry" , Churchill Livingstone, Edinburgh, London, Melbourne and New York, 1982).

According to this method, during most medical procedures, the position of the terminal hinge axis, transferred from the patient to the articulator using the facial arch, is set at the point average on the skin on the side of the articular heads. It is called the “arbitrary articulated axis” and is located 13 mm from the top of the tragus on the line connecting the top of the tragus and the outer corner of the eye (p. 149, Fig. 198 “a”). This point is marked on the skin, and the detail of the facial arch imitating the articular head is placed on the mark (Fig. 198 "6"). When transferred to the articulator, the specified part of the facial arch is located directly under the axis of rotation of the part simulating the articular head.

The disadvantage of this method is the mismatch of the calculated point through which the axis passes with the axis of the head of the lower jaw.

There is a method of finding the axis of the head of the lower jaw of the patient, which consists in the fact that on a line passing through the point of Po (the upper edge of the ear canal) to the point O (the lowest edge of the orbit) in the direction of the point O at a distance of 12 mm fix the point from which, down a line towards the tragus, perpendicular to the Po-O line, measure 4 mm and put a point that is the axis of the head of the lower jaw of the patient (D. Seifert, V. Jerolimov and V. Carek “Terminal Hinge Axis - Hobo Point - Frankfurt Horizontal Relations ”, Coll. Antropol. 24 (2000) 2: p. 479-484, Received for publication September 21, 2000). This decision was made as a prototype for the claimed method.

The disadvantage of this method is that it is derived on the basis of an examination of patients with at least 28 teeth with a clear occlusal contact who did not have any injuries and orthodontic treatment or intervention. For other patients with deviations due to various reasons, the application of this method does not always allow reliable information about the point of the actual position of the axis of rotation of the head of the joint of the lower jaw using only this known coordinate method.

Disclosure of invention

The present invention is aimed at achieving a technical result, which consists in accurately finding the axis of the head of the lower jaw of the patient and increasing the level and accuracy of treatment of any complexity. The specified technical result is achieved by the fact that the method of finding the axis of the head of the lower jaw of the patient consists in the placement of cutaneous points from a radiopaque substance or material on the patient’s skin and the subsequent removal of a CT scan in lateral projection with the reflection of these points, while the first cutaneous point is placed on the line, passing from Tragus medialis to the deepest point of the orbit, at a distance of 11 mm from Tragus medialis towards the orbit, the second cutaneous point is placed at a distance of 4 mm on the line, emanating from the first cutaneous point, which is perpendicular to the line from Tragus medialis to the deepest point of the orbit, the third and fourth cutaneous points are located 2 mm apart from the second cutaneous on a line parallel to the line from Tragus medialis to the deepest point of the orbit , on a CT scan, they draw the first line from the upper edge of the ear canal to the point corresponding to the lower edge of the orbit, from this line draw a perpendicular line downward, passing tangentially along the posterior convex edge of the articular the ovaries of the lower jaw, then draw a perpendicular line downward, running tangentially along the front convex edge of the joint head of the lower jaw and the lower line passing through the neck of the joint, which parallel to the first line, define a point inside the outlined zone, which is the axis of the head of the lower jaw of the patient, and it the coordinates with respect to the projections of the cutaneous points on this radiograph, and then the projection of the point of the axis of the head of the lower jaw of the patient on this radiograph is transferred to the patient’s skin in the area previously applied cutaneous points.

These features are significant and are interconnected with the formation of a stable set of essential features sufficient to obtain the desired technical result. Disclosure of invention

The present method is illustrated by drawings, in which:

figure 1 - the position of the first radiopaque point;

FIG. 2 - the position of the second, third and fourth radiopaque points;

FIG. 3 - the formation of the zone of the head on the x-ray.

The best embodiments of the invention

The basis of the claimed method is the statement that it is necessary to control the cutaneous projection of the axis of the head of the lower jaw using X-ray examination methods (computed tomography) of the temporomandibular joint, because the position of the joint of the lower jaw can be shifted (forward, backward, downward). Therefore, the average proposed cutaneous points do not in all cases correctly display the axis of the head of the lower jaw. All cutaneous points are performed with a radiopaque substance (marker) or metal balls or pieces (in the form of circles) of aluminum foil are glued to the places corresponding to these shocks.

The claimed method is implemented by the following sequence of actions.

1. On the patient under examination, along the line from Tragus medialis to the deepest point of the orbit, put the first point on the patient’s skin with a radiopaque substance (Fig. 1). The location of the first point is 11mm anterior to Tragus medialis in the line shown.

2. Next, the next point is placed 4 mm higher (above the first point). This second point is placed on the line coming from the first point, which is perpendicular to the line from Tragus medialis to the deepest point of the orbit (Fig. 2).

3. The next third and fourth cutaneous points are located at a distance of 2 mm on the sides (anterior and posterior) from the second point. These two points are plotted on a line parallel to the line from Tragus medialis to the deepest point of the orbit (Fig. 2).

The setting of these points is carried out in an approximate projection of the location of the articular head of the lower jaw.

In order to control and find exactly the axis of the articular head of the lower jaw, it is necessary to perform an X-ray examination of the joint area.

4. On a CT scan in lateral projection draw a line from the point of Po (the upper edge of the ear canal) to point O (the lowest edge of the orbit). A perpendicular downward line is drawn from this line, passing tangentially along the posterior convex edge of the articular head of the lower jaw. Next, draw the next perpendicular line downward, passing tangentially along the front convex edge of the articular head of the lower jaw. The bottom line passes through the neck of the joint, and it is drawn parallel to the line passing through the points of Po-O (Fig. 3).

5. Thus, we get a limited area in which we find relative to the set points the middle axis of the articular head of the lower jaw.

Subsequently, the position of the axis on the skin is corrected (by counting from cutaneous marks directly or through a similarity) and thereby obtain an accurate image of the axis of the articular head of the lower jaw on the skin.

Inside the outlined zone, a point is determined which is the axis of the head of the patient's lower jaw, and its coordinates with respect to the projections of the cutaneous points on this radiograph, and then the projection of the point of the axis of the patient's lower jaw on this radiograph transferred to the patient’s skin in the area of previously applied cutaneous points.

The axis of the head of the lower jaw is the axis of rotation of the lower jaw. The exact location of this axis allows you to increase the level and accuracy of treatment of any complexity.

Industrial applicability

The present invention is industrially applicable, implemented, used in practice and shows high efficiency in reducing the installation time of control points that are reliable for a given patient and improving the quality of treatment.

Claims

Claim

The method of finding the axis of the head of the lower jaw of the patient, which consists in staging cutaneous points from a radiopaque substance or material on the patient’s skin and then taking a CT scan in lateral projection with the reflection of these points, while the first cutaneous point is placed on the line from Tragus medialis to the deepest points of the orbit, at a distance of 1 1 mm from the Tragus medialis towards the orbit, the second cutaneous point is placed at a distance of 4 mm on a line starting from the first cutaneous point, which is perpendicular the line from Tragus medialis to the deepest point of the orbit, the third and fourth cutaneous points are located 2 mm apart from the second cutaneous on a line parallel to the line from Tragus medialis to the deepest point of the orbit, the first line is drawn on a CT scan the upper edge of the auditory meatus to the point corresponding to the lower edge of the orbit, draw a perpendicular line down from this line, passing tangentially along the posterior convex edge of the articular head of the lower jaw, then draw a perpendicular a downward line running tangentially along the front convex edge of the joint head of the lower jaw and a lower line passing through the neck of the joint, which is parallel to the first line, define a point inside the outlined zone, which is the axis of the head of the lower jaw of the patient, and its coordinates with respect to the projections of the cutaneous points on this x-ray, and then the projection of the axis point of the head of the lower jaw of the patient on this x-ray is transferred to the patient’s skin in the area of previously applied cutaneous points.