Determining the height of the bite

In the literature, many methods of determining the height of the bite. The greatest theoretical and practical value in two ways: anthropometric and anatomical and physiological. Anthropometric method. In medicine, has long sought to establish regularities in the structure of the human body. There are about 115 canons by which the proportionality test of the human body. So, for example, is known canon "golden section" seizing. He proposed a special compass to determine the proportion of the face. There is a Fridshes law on which the horizontal line connecting the pupils, head divides into two equal parts. The upper half, in turn, is divided into frontal and scalp. The lower half is divided by a horizontal line into two parts: the first - the root of the nose to the chin, and the second - from the root of the nose to the line of the pupil. Face is divided into three parts by four horizontal lines: one running along the border of the hair, the second - on top of the eyebrow, and the third - through the nose, and a fourth - a chin point. In the literature, there are indications of the possibility to use these laws to determine the height of the bite in prosthetics edentulous jaws. For example, if in the absence of teeth lost height of bite, remain unchanged middle and upper part of the face. Measuring the distance from the brow to the wings of the nose, can be properly set the height of bite. It is interesting to offer, that the distance between the pupils to line closing of the lips is the distance from the root of the nose to the chin in serried teeth. However, these canons are based on purely theoretical assumptions and anatomically unfounded. Canons determine the average proportion of persons without regard to individual differences. Furthermore, parts of morphological variants, characterized by imbalances.

V. Vorobiev wrote that "some individuals, depending on gender, age, race, constitution, from the effects of social and professional conditions of existence and the effects of certain pathological factors are more or less deviate from the ideal proportions of the respective canons."

P. Lesgaft also believes that these proportions are approximate and cannot therefore serve as the basis of the morphological law. Thus, the anthropometric method of determining the height of occlusion should be found to be incorrect. Anatomical and physiological method. In determining the height of the bite anatomical and physiological methods guided by conventional anatomical entity, the configuration of its soft tissues and physiological state of the rest of the mandible. The latter is the main reference in this stage. Further correction configuration entity, moving forward or backward lips or cheeks, smoothing wrinkles on the face produced by expanding or narrowing the arch occlusal ridges, thickening or thinning of these or other areas, but not by changing the height of the bite. If there is a match between the physiological and aesthetic features, you can be sure that the height of the bite properly assessed. If there is no match, you must set the height of the bite on the physiological characteristics, and aesthetic shortcomings eliminate the formation of artificial gums and related artificial teeth. As mentioned earlier, the position of the lower jaw in a state of physiological rest is the source for determining the height of the bite and the establishment of the central occlusion.Gubskaya AI (1954) physiological rest position was as follows: "the lower jaw hang down from the top by 1-2 mm, lips are closed, the language freely in the mouth and the tip of the front part of the sky, the musculature is in a state of tonic tension ".

E.I. Gavrilov (1968) writes that in the position of relative rest jaw muscle energy costs in comparison with the state of functional activation are minimal. Economical use of muscle power is the main feature of the tonic state under the control of the higher nerve centers. In turn, the tone of the masticatory muscles - is the sustainable reduction of reflex related to conservation of the characteristic position of the lower jaw. The basis of all voluntary muscles tone is miotatic reflex. Based on the above physiological nature resting position, this condition can be defined as follows: the rest position - it is a condition of the lower jaw to the top, where all the chewing muscles are in a state of minimal and balanced tonic tension. To determine the height of the bite of physiological rest offer the patient to utter the sound "m" or "and" or any phrase. After these functional tests lower jaw is set to physiological rest. Anatomical feature here is an easy stress-free closing of the lips. Kemeny said that his lips only fit together without stress, when the teeth bite block or do not touch, and between them is clearance of 2-3 mm. Tight coupling of the lips is the result of reducing not only the circular muscles of the mouth, and muscle closers. They are in a functional unity and interaction with muscle-discoverers. Only at coordinated action of these two muscle groups may dense closing lips. This means that only the lips may be in tension, a loose state where the lower jaw is in a state of physiological rest. In the literature, a large number of measurement devices in the form of compasses and rulers, with emphasis to the chin, with which the authors propose to measure the height of physiological rest. These devices, however, are not widely known. Line with the emphasis not like, apparently, because the topography of the chin does not match the horizontal fence line, at right angles to the vertical part. Also raises objections method of physiological rest height and the height of the bite compass because of its inaccuracy and inconvenience. For measuring the physiological rest and height of bite usually use dental spatula. The blunt end of a spatula, pre-painted carbon paper or chemical quarantine, mark a point or a line at the root of the nose, around its fixed part. Trowel applied to the soft tissues of the upper lip and chin with no pressure on them. The index finger of the right hand placed below the chin, slowly moving up to light contact with the soft tissues of the chin. The data obtained measurements corresponding to a height of physiological rest, mark a line on the plate of wax paper or in the middle of the face. The second line is carried by 2-3 mm below the first, and thus find the desired height of bite. To verify the height of occlusion functional tests. Examinee offer utter the words: "echo", "convincing", "right", etc. If the height of the bite is correct, between the occlusal ridges formed space equal to 2-3 mm. If the sample size in functional occlusion between the rollers is less than or greater than 3.2 mm, the height of the rollers refine by cutting them with a layer of wax or increasing it. Rules and methods determine the centric. Subject to certain rules and techniques can accurately establish a central occlusion. If errors occur, in most cases, they can be immediately detected and eliminated. Rules and procedures can be divided into main, auxiliary and control.

Basic rules and techniques:

1. The patient's head should be in the upright position, and the chin - at elbow doctor, to be little effort to set the jaw in the central occlusion.

2. Wax Strips with which fixed upper and lower occlusal rollers should be well warmed up and is located in the middle of the lower platen.

3. Thumb and forefinger of his left hand hold and push the base to the top of the upper jaw and the lower jaw to the base. Palm of the right hand placed on the chin patients referred lower jaw back and up to the full and uniform contact occlusal ridges.

4. We cannot allow the patient to close his jaw arbitrarily, since in most cases the lower jaw must be installed in the wrong position.

5. Active movement of the lower jaw back and up must be done from a position of un-opened mouth and half-closed, when the articular head is moved from the top of the articular tubercles and are on their lower slope. From this position it is easy to establish the lower jaw in centric.

6. With significant atrophy of the alveolar process of the lower jaw is expedient to do on the vestibular surface of the lower roller of 54:45 teeth, two wax lip-lock. Placed at the ends of these glides index finger and thumb of his left hand, which was pressed to the lower base of the alveolar process and thus prevent its backward movement.

7. After determining the centric bases with rollers removed from the mouth, is immersed in cold water, then wipe with a cotton swab and placed on the model. Heated spatula cut the excess wax, squeezed between the bite block, and smooth over the burner flame roughness on their labial surfaces. When orthognathic bite edge rollers with facially throughout must be on the same level, without steps.

Helper methods and rules:

1. Offer the patient to bite your fingers on the side sections of the rollers.

2. Offer the patient to raise the tip of the tongue to the palate and swallow with saliva. The lower jaw is pulled back and placed in the central occlusion.

3. Offer the patient close his teeth, and, without opening them, to make 2-3 swallowing.

4. Before fixing the mandible in centric relation to the patient to make some offer of swallowing movements, this raises the swallowing reflex and the lower jaw is in the distal position, not moving forward, even when muscle tension-vydvigateley.

5. By the middle of the upper edge of the oral basis reinforce the wax ball. At the closing jaws of the patient offer to touch the tip of his tongue. With this move the lower jaw language set in the central occlusion.

Functional method of determining the centric in establishing a central Bite to consider the reflexive nature of this relationship and from that adhere to the following basic rules:

1. The patient does not need to know about the purpose of your event, as only an untrained person can perform the necessary acts automatically, unconsciously, therefore, correctly.

2. Hands of a doctor should be involved in the process of fixing and Bite, that is impossible to maintain bases in the cylinders to "guide" the jaw to the back position, since it usually causes a reaction.

3. Bases and bite block should be strong enough, evenly and at the same time link up with correctly shaped boundaries.

To relax the muscles of the patient is invited to quickly calculate for 2 minutes.

Simultaneously well heated strip wax, then quickly impose it on the lower roller. Enter the bases in the mouth and ask the patient to swallow saliva. During swallowing reflex lower jaw is set in central occlusion. Bite the wax bases are then cooled and transferred to a plaster model of the jaw.

Comparative evaluation of methods of fixation of the mandible in centric in the literature, many methods of fixation n / h in central occlusion. In comparative evaluation plays a significant role complexity. Sophisticated methods and techniques can be applied only when compared to the simple and accessible methods they provide higher quality performance. The fixation of the wax cylinders centric with metal staples made by three U-shaped clips, they are administered in a heated state by crampons forceps in the upper and lower rollers - two in 54:45 / 54:45 and one in 1:1 / 1:1. The disadvantage of this method consist in the fact that the artificial teeth can be installed only in bitelock, where no split strengthening the upper and lower models. In the articulator, which require separate gipsum - before the top models, and then the bottom, fastened with staples model can not be plastered in a spatially correct position.

Gysi extra oral proposed method of determining the central occlusion. When using this method bases should be made of solid material - shellac, plastic, and occlusal rollers - made of thermoplastic material. After determining the occlusal plane and the height of the bite on smooth rollers to the vestibular surface of the lower roller on a level with him with two arcs attached plaque. To the vestibular surface of the top roller on one level with him respectively arrangement of teeth, plaque attached springy pin that in working condition must be 2 mm below the roller. The middle part of the plate covered with a thin layer of melted black wax. Bases with rollers and devices attached to them are introduced into the mouth patient, offer him close his jaw and produce for 1-1.5 min. movements of the lower jaw to the right and to the left to muscle fatigue. As a result of these movements in the wax forms an angle with the top towards the front. The coincidence of the pin with the top corner corresponds

Date: 2015-01-02; view: 1242