RU2035891C1 - Method for determining caries lesion intensity - Google Patents

Abstract

FIELD: medicine; stomatology. SUBSTANCE: method involves calculating mean hygienic value of the index in population in examining oral cavities of patients. Intensity index is calculated from a formula. EFFECT: simplified process, enhanced reliability in evaluating the degree of caries lesion. 1 dwg, 3 tbl

Description

 The invention relates to medicine, namely to dentistry and can be used for epidemiological examination of the population.

 No similar solutions were found.

The prototype of the invention is a method for determining the intensity of caries by diagnosing in the oral cavity carious, filled and extracted teeth (KPU) in each patient and then calculating KPU for the group examined according to the formula [1]
The disadvantage of the prototype is the complexity of the method due to the need to examine all the teeth of each patient, the use of various dental instruments, the calculation of individual KPU and the group examined by the formula, which also requires a lot of time. 6.5 minutes are spent on examination of 1 person, and 11 hours per 100 people.

 The aim of the invention is to simplify the method and reduce the time for examination.

a

+b
В просмотренных источниках информации указанные существенные признаки не обнаружены, что позволяет говорить о "новизне" изобретения.The goal is achieved by the fact that the indicator of the intensity of the disease of caries (Y) during an epidemiological examination is calculated taking into account the average value of the hygiene index (X) per group examined by the formula

a

+ b
In the reviewed sources of information, these essential features were not found, which allows us to talk about the "novelty" of the invention.

)) и интенсивностью заболевания кариесом ((

)), что позволило вывести новую формулу расчета результата эпидемиологического обследования, значительно упростить и сократить время на эту процедуру.In contrast to the prototype, the invention established a linear relationship between the hygiene index ((

)) and the incidence of caries ((

)), which allowed us to derive a new formula for calculating the result of an epidemiological survey, to significantly simplify and reduce the time for this procedure.

 The method is as follows.

 Take a group of examinees (10.20.100, etc. people), carry out staining with a tampon with methylene blue for 6 central teeth and calculate the hygiene index (X) according to the degree of staining for each person, then the average value of the hygiene index per group of examinees is substituted into formula Y = aX + b, and calculate the average value of the intensity of the disease of caries. Assessment of the intensity of caries KPU (Y) depending on GI (X) are according to table. 1.

 The derivation of the formula Y = aX + b and the calculation of the values of a and b (linear regression parameters) were carried out using the least square method (Lobatskaya N. L. Morozov Yu.V. Dunaev A.A. Higher mathematics. Minsk: Higher school, 1987, p.204-209).

 The calculation of indicators of the intensity of the disease of caries Y (KPU) depending on the hygiene index X (GI) was carried out using electronic computing technology and the programmed microcalculator Electronics MK-61 (according to the program proposed by the author from KSMI Asanov M. A. Statistical processing of the results chemiluminescent studies, Issues of chemiluminescence. NP cooperative "IRA" T.1, N 2, M. 1991, p.5).

представляет дискретную величину, изменяющуюся от 0 до 3 с шагом 0,25, следовательно, для каждого значения Х=х имеется свое распределение Y с определенными средними значениями и депрессией.Consider a random sample of paired observations (X, Y) from the studied population (children aged 15 years), where X (GI) is the hygiene index, Y (KPU) (caries +)

represents a discrete value, varying from 0 to 3 in increments of 0.25, therefore, for each value X = x there is a distribution Y with certain average values and depression.

и

существует корреляционная зависимость, т.е. изменение гигиенического индекса влечет за собой изменение математического ожидания Y показателя интенсивности.Between quantities

and

there is a correlation dependence, i.e. a change in the hygiene index entails a change in the mathematical expectation Y of the intensity indicator.

, где М математическое ожидание соответствующей величины;
σXσY- генеральные средние квадратические отклонения величины
Х и Y
В нашем случае коэффициент корреляции между Х и Y составил
r 0,9
Исходя из свойств коэффициента корреляции, делается вывод:
Связь между КПУ и гигиеническим индексом является тесной, т.к. r 0,9.The correlation coefficient is calculated by the formula:
Z

where M is the mathematical expectation of the corresponding value;
σXσY - general mean square deviations of the quantity
X and Y
In our case, the correlation coefficient between X and Y was
r 0.9
Based on the properties of the correlation coefficient, the conclusion is drawn:
The relationship between the CPU and the hygiene index is close, as r 0.9.

 The presence of a linear correlation between the two quantities X and Y is established. This dependence is described by the linear regression equation.

Y aX + b, where a is the regression coefficient;
b some parameter.

= aX+b
a,b параметры линейной регрессии

$\genfrac{}{}{0ex}{}{\text{по}}{\text{кв}}$ _а $\genfrac{}{}{0ex}{}{\text{методу}}{\text{дратов}}$ ^{наименьших}

Расчет на ЭВМ (см. источник выше) значений зависимости интенсивности заболевания кариесом Y (КПУ) от гигиенического индекса

(ГИ) на определенную группу осмотренных (только 15-летние подростки) с 90% доверительным интервалом приводится в табл. 2 (выборка из всего массива):
Анализ полученных конкретных данных на эту группу привел к уравнению вида:
Y 1,25 X +1
Результаты вычислений представлены на чертеже, на котором по оси абсцисс отложены значения гигиенического индекса

, а по оси координат Y (КПУ). Плюсами отмечены средние значения

и указаны их 90%-ные доверительные интервалы, сплошной линией выделено полученное уравнение линейной регрессии: Y 1,25 X + 1
Интенсивность заболевания кариесом в группе 15-летних подростков дана в табл. 3.The a and b values were calculated using the least squares method (see source above), for example
Yj dependent i 1,2.kj 1,2.l
Xi parameters n number of observations
Y _j = aX + b

= aX + b
a, b linear regression parameters

$\genfrac{}{}{0ex}{}{\text{by}}{\text{sq}}$ _and $\genfrac{}{}{0ex}{}{\text{method}}{\text{drat}}$ ^{the smallest}

Calculation on a computer (see source above) of the dependence of the intensity of the disease of caries Y (KPU) on the hygiene index

(GI) for a specific group of examined (only 15-year-olds) with a 90% confidence interval is given in table. 2 (selection from the entire array):
An analysis of the obtained specific data for this group led to an equation of the form:
Y 1.25 X +1
The calculation results are presented in the drawing, on which the values of the hygiene index are plotted along the x-axis

, and along the coordinate axis Y (CPU). Pluses marked average values

and their 90% confidence intervals are indicated, the solid line indicates the obtained linear regression equation: Y 1.25 X + 1
The intensity of caries in the group of 15-year-olds is given in table. 3.

(КПУ) 2,25+1 2,81+1 3,81 Следовательно, для подростков в возрасте 15 лет интенсивность кариеса при гигиеническом индексе 2,25 равно 3,81. Исходя из табл. 1, считают интенсивность заболевания умеренной.PRI me R. To determine the intensity of caries (KPU) in the group of 15-year-olds, the hygiene index X (GI) in this group is determined. Suppose for this group the average value of the hygiene index (X) is 2.25, we substitute it in the formula:

(KPU) 2.25 + 1 2.81 + 1 3.81 Therefore, for adolescents aged 15 years, the intensity of caries with a hygiene index of 2.25 is 3.81. Based on the table. 1, consider the intensity of the disease moderate.

 Thus, the use of the proposed method in epidemiological studies makes it possible, in comparison with the prototype, to obtain an objective quantitative assessment of the intensity of caries without separate long-term diagnosis in the oral cavity of caries, filled and extracted teeth, which can significantly reduce the time for examination due to the availability and simplification of the method. According to the proposed method, the determination of the intensity of caries in the group of 100 patients examined takes 1.5 hours instead of 11 hours according to the previous method.

Claims (1)

METHOD FOR DETERMINING THE INTENSITY OF CARIES DISEASE by examining the oral cavity and calculating the results, characterized in that, in order to simplify the method, the rate of caries disease intensity Y is calculated taking into account the average value of the hygiene index by the formula
Y aX + b,
where X is the average value of the hygiene index;
a and b are linear regression parameters.

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