Primary Teeth and Hair as Indicators of Environmental Pollution.

OBJECTIVES: To study the influence of environmental pollution on the mineralization of dental hard tissues by using biosubstrates: teeth and hair. : STUDY DESIGN: At the first stage epidemiological survey was conducted in polluted and less polluted areas of Tbilisi (Georgia). We studied 525 children aged 3 and 4 years. Caries prevalence and intensity was defined by the methodology of World Health Organization. At the second stage the chemical elements content was studied in hair and teeth hard tissues of 24 children by X-ray fluorescent spectroscopy method. RESULTS: The prevalence of dental caries in the polluted region was 46%, caries intensity--1.92 (± 2.842). In the less polluted region prevalence was 37%, caries intensity--1.47 (± 2.571). These data are statistically reliable (p < 0.05). The study of hair and tooth tissues showed that the toxic elements (Pb, Hg, Sn, Ti) content in these tissues was higher in environmentally unfavorable than in favorable conditions. CONCLUSION: Hair and dental tissues can be used as indicators of environmental pollution. Our survey showed that toxic elements content in dental hard tissues was higher and the level of essential elements was less in polluted than in less polluted areas of Tbilisi.

[The level of matrix metalloproteinases and type IV collagen in the gingival mucosa under different clinical forms of periodontitis in pre-and pubertal periods and their prognostic value].

The purpose of the study - the analysis of the prevalence and gravity of periodontal diseases among school adolescents and detection the relationship between the degree of periodontal tissues changes and the hormonal status of the prepubertal and pubertal periods. The total number of observations - 618 Tbilisi schoolchildren at the age of 9 to 17 years. Cohort group (n=50) was divided by age: 1) 9-13 years (n=26), 2) 14-17 years (n=24). The material for morphological and immunohistochemical study were the samples of periodontal tissues, received during the tooth extraction according the orthodontic testimony. The samples of the gingival mucosa was stained by hematoxylin and eosin, in the same samples the Matrix Metalloproteinases expression and activity were determined by immunohistochemistry using a primary antibody MMP-1 and MMP-2 ("Novocastra", UK). The results of immunohistochemical reactions were estimated in scores by semiquantitative method. For the detection of type IV collagen in basement membranes the samples were stained by the "Direct Red-80" ("Sigma"). It was found that the increase of Matrix Metalloproteinases expression and the type IV collagen degeneration in basement membrane depend on the age, particularly the expression of MMP-1 and MMP-2 in the period of 14-17 years (puberty) is upwards than in the group of 9-13 years. Studies have also demonstrated the clinical significance of Matrix Metalloproteinases ММР-1, 2 activity indicating the dissociation of the extracellular substance and type IV collagen in the assessment of severity and prognosis of periodontal complex pathology in pre-and pubertal periods.

[Correlation between the ecological risk factors and significant index of caries in young children].

The influence of eco-pathogenic factors on mineralization of teeth hard tissues at early age was studied in 525 young children, 3 to 4 of ages. Tooth caries index was detected according to the indexes provided by WHO (World Health Organization): prevalence, intensity (dmf) and Significant Index of Caries (SIC). The studies revealed that the average rate of dental caries for studied group living in regions with ecologically favorable conditions is relatively lower than in ones living in regions with unfavorable conditions and equals to 39.6% and 63.6%, respectively. Comparative analysis of average and significant indexes ​ of dental caries showed that the difference is minimal in children population living in favorable conditions (1: 1.7) in comparison with the children living in ecologically contaminated regions, where the significant index exceeds the average one approximately three times as much. According to the obtained results, it should be concluded that the dynamics of dental caries is mostly expressed in young children living in regions where air-pollution (with chemically aggressive substances) index several times exceeds the maximum allowable coefficient. Consequently, development and implementation of the special programs for caries-prevention in children population with low rate of caries-resistance, living in the above-mentioned conditions is of great importance.

[Periodontal tissue pathology in pubertal children (pupils)].

The study aimed at investigation of the rate of periodontal pathologies in juvenile adolescents, the analysis of the severity of the disease and detection of the correlation between the periodontal tissue pathology and hormonal status of pre-and pubertal periods. A stomatologic (dental) status of 618 pupils, 9-15 of ages in Tbilisi General Education Schools has been studied--to detect the rate and intensity of periodontal pathologies and analyze the influence of hormonal changes of juvenile periodontal tissues. According to the obtained results we can conclude that the high rate of periodontal diseases has been fixed in pre-pubertal and pubertal schoolchildren (pupils). It should be emphasized that the degree of periodontal tissue pathologies increases with age. In addition, the mentioned pathology was more frequently fixed and expressed in girls, 12-13 of ages and in boys, 14-15 of ages. Juvenile periodontal pathologies most frequently is generalized, which most frequently is aggravated with the existence of jaw-dental anomalies and the poor oral hygiene status.

[The impact of ecopathologic factors on the development of dental diseases].

Environment pollution is listed as the most significant problem of the 21st century. In cities throughout the world, long periods of heavy air pollution have caused increase of illness rates. Effect of air pollution on the dental status of children in Tbilisi, Georgia (Caucasus) was studied. The research was conducted on 311 children aged 3-4 according to the standard method of WHO (caries spread, intense cavities and non cavitated teeth decay). A high rate of dental cavities (approx 98, 9%) and 8 individual cases of non-cavitated pathology of hard tissue of teeth was encountered in Tbilisi. It was found that tooth decay does not depend on the quotient of air pollution; at the same time, ecological index considerably affects the data of intense dental caries: it is higher in those parts of the city, where the pollution of the environment is high (6,0% and 3,9% accordingly). The research shows that the increase of ecotoxins in the atmosphere can affect not only the organs and system of the human organism, but also appears to be a risk factor for future dental pathology.

[Content and metabilism of nitric oxide in substrates of oral cavity and their role in pathogenesis of periodontite disease].

Content and metabolism of free NO in saliva, fluids of periodontal pockets and gingival tissue has been investigated by EPR (electron paramagnetic resonance) method with the use of nitric oxide spin-trap in patients suffering from periodontitis. It was found that increased generation of nitric oxide at early stages of periodontitis is of protective nature. However, at serious disorders of mitochondrial respiration and exaggerated formation of generators of reactive oxygen, nitric oxide converts into citotoxic peroxinitrite leading to destruction of parodontal tissue; part of free nitric oxide produces FeSNO, which in turn, supports and decreases content of free NO in gingival tissue. As a result, decreases local antimicrobial protection, hemocirculation, tissue nutrition, progresses inflammation. Periodontitis decreases local immunity due to NO deficiency in gingival tissue. Reduced content of NO in gingival tissue decreases regeneration ability of cells, which in turn, leads to deterioration on gingival tissue.

[Efficient methods of prevention and treatment of permanent first molars before completion of root formation].

Examination of first molars among 124 children, age range 7-8 years, showed high intensity of caries disease. Detection and prevention of risk factors, also practical use of prevention and treatment methods existed in clinical stomatology, especially before completion of root formation of permanent teeth, is extremely important. Results showed that deep fluoridation of fissures of permanent teeth with enamel Hermetisation Liquid (A. Knappfost) is very effective method for preventing dental caries. Caries was reduced in 96% of cases. Cultivation of cavity with above-mentioned solution, right before restoration prevents reoccurrence of caries and pulpal complications that is very important for future growth and formation of roots of permanent teeth and for functional value of permanent teeth themselves.

[Some causes of systemic demineralization of dental solid tissues in children of early age].

Among the risk factors causing generalized demineralisation of dental solid tissues in young kids (disturbances during antenatal development of embryo, frequent sickness of infant, etc.) the most important factor is the type of breath feeding of infant. Such factors as the good balance of calcium and phosphor in mother's milk contribute to the maintenance of healthy dental tissues. As our data shows in majority of kids (98%) with artificial feeding type, calcium and phosphorus levels in the blood serum and their rate (<1.30) were decreased, along with that hydrogen ion concentration in oral fluids was also decreased. All above mentioned has influence on physical-chemical reactions occurring in tooth enamel, increases enamel penetration and reduces buffer characteristics of oral fluids. Those problems are especially important for Georgia, where the level of fluoride in the drinking water is very low (0.35-0.45 mg/l).