Justification of methodology of research of elektrovozoremontnij

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Before you begin to develop psychologically and physically substantiated methods of research of elektrovozoremontnij the tooth nerve, it was necessary to solve a number of issues. The answers were supposed to form the basis of this method.
As already noted above, the main measure of anxiety is minimal (threshold) the intensity of irritation that can cause agitation tissue. As irritants are different kinds of energy. However the best from inadequate irritants is the electric current, as it has a number of advantages: current strength and duration of its validity can be easily and precisely dosed out, irritation can be repeated many times in a row without damage to tissue. Electric current is the only stimulus that allows you to explore a variety of tissues, little or no exposed other irritants.
For the study of excitability of the teeth in the dental clinics was widely used until the mid-fifties of the current century AC the city network, which used a small step-down transformers. Individual doctors used with apparatus for galvanization. In both cases was determined threshold voltage in arbitrary units.
It was necessary to go to the definition of the threshold current. And for this it was necessary to know, at currents which forces generally react teeth. Already the first preliminary studies have shown that the excitation of nerve of the tooth sufficient currents of very low intensity, measured by microampere (thousandths of milliampere), and it concerned all teeth (starting from the Central incisor and finishing the third molars).
The second issue was the type of current. Which of them is better to use - constant or variable (from a city network)? As very precisely, you can only measure the power of direct current (and without precise definition of threshold power it was impossible to think of creation of a precise methodology of the study of excitability of nerve of the tooth), we chose him AC, moreover, that it was about a very weak currents. But soon we realized that without AC will be hard to do. In the study DC in some cases, faced with the phenomenon of polarization, impairing and sometimes the definition of the threshold. The essence of this phenomenon is as follows.
In Windows Explorer second kind (and hence in the tissues of the human body) electric current is the motion of charged particles in opposite directions. On his way to the poles of the current source of charged particles meet a huge number of semi-permeable membranes that the particles pass, others are detained. These barriers electromotive force in the opposite direction skipped current. This electromotive force can be significant.
When passing through the body of the AC during each half-cycle is also changed the concentration of ions in a semi-permeable membranes. But arisen within one half-period changes of the concentration shall be resolved in the next half-cycle current reverse direction, resulting in the phenomenon of polarization are not as pronounced as with direct current. With increasing frequency, when the current is faster changes its direction, the phenomenon of polarization is becoming less pronounced. That is why the resistance of tissues more direct current than the variable, and the higher the frequency, the lower the resistance.
Next was the question of where to put the electrodes are both on one tooth or a tooth, and the second on any area of the body. The first option we have from the beginning seemed impractical. When placing both of the electrodes on the tooth current passes through the crown and to get a reaction from the root of the pulp was impossible. In addition, by this method, it is impossible to know what pole and when (at the circuit or open circuit) feeling. That's why we chose the so-called pseudounipolar methods: one electrode lead with an area of 300 - 400 cm2 with hydrophilic pad soaked with warm tap water, put on the hand or forearm; as active electrode is placed on the tooth, we first used a wire made of pure silver, covered by electrolytic the silver chloride (depolarizes electrode).