Hard Tooth Tissues Research Articles

Changes in immunological parameters in patients treated using direct and indirect restorations of the hard tissues of the anterior teeth in combination with an antioxidant.

The problem of aesthetic restoration of the hard tissue defects in the anterior teeth and the choice of materials for quality restorations, which can include direct composite or indirect ceramic restoration, in particular ceramic veneers, is currently extremely important in clinical dental orthopedics. Currently used composite and ceramic materials are known to have different effects on the conditions of the marginal periodontium and the local immunity in the oral cavity. The condition of periodontal tissues should be taken into account when choosing a way to eliminate this pathology. Therefore, we propose a new approach to treatment, which is the use of indirect ceramic restorations in combination with an antioxidant. The purpose of this article is to increase the effectiveness of treatment in patients with defects in anterior teeth using indirect ceramic restorations with antioxidants. To study the intensity of immune reactivity in patients with existing defects of the coronal part of the anterior teeth, we analyzed the levels of lysozyme and sIgA in the oral fluid. The results of the studies confirm the advantages of indirect ceramic restorations over direct composite ones in the treatment of hard tissue defects in the anterior teeth, taking into account the levels of immunological reactivity and using an antioxidant drug Resverasin. According to the results of our clinical studies, Resverasin significantly shortens the duration of the adaptation period and increases immune reactivity in the oral cavity, especially in combined pathology.

Diagnosis and treatment planning of traumatic dental injury

Traumatic dental injury (TDI), one of the common dental diseases, is defined as acute injuries to tooth hard tissues, dental pulp and/or periodontal tissues caused by sudden forces. Based on the Guidelines for the Management of TDI by International Association of Dental Traumatology (2012) and the Recommended Guidelines of the American Association of Endodontists for the Treatment of TDI (2013) for the permanent teeth, and combined with the authors' clinical experiences, the contemporary classification and clinical perspective of TDI were introduced in detail. Dental clinicians should understand and master the international guidelines for the management of TDI, including proper diagnosis, standardized treatments and regular follow-up, so as to obtain the favorable outcomes.

Novel insights on the etiology, diagnosis and prevention of dental erosion

Dental erosion is a progressive loss and damage of tooth hard tissues caused by contacting acidic substances. It is an occupational disease for workers who make acidic products such as acids, vinegar, etc. In the past decades, a rising of prevalence rate of dental erosion, especially in the youth groups, along with the change of dietary habits and the increased consumption of sweet and acidic diets, has attracted public's attention. This article reviews and analyzes the literature on the prevalence, etiology, prevention and treatment of dental erosion, so as to provide guidance for early diagnosis and treatment of dental erosion and support for making occupational disease prevention strategies.

Diagnosis and treatment of internal resorption of teeth: a review of literature and clinical case

Internal resorption is a separate category of diseases of hard tissues of teeth, characterized by the loss of dentine as a result of activation and activity of osteoclasts. The article discuss issues concerning etiology, the prevalence of internal resorption, its diagnosis, emphasise the contribution of computed tomography in the diagnosis and prediction of treatment success, clinical decisions and therapeutic treatment of this disease. Describe modern endodontic treatment methods, including the use of magnification, ultrasound in endodontic treatment, the use of certain materials for temporary and permanent root canal filling. Under these conditions, the prognosis of conservative treatment of internal resorption of dental hard tissues is improved, even if there is a perforation of the walls of the tooth cavity.

ВЕРОЯТНОСТЬ РАЗВИТИЯ СТОМАТОЛОГИЧЕСКОЙ ПАТОЛОГИИ У ДЕТЕЙ, ПРОЖИВАЮЩИХ В ЗОНАХ РАЗЛИЧНОЙ АНТРОПОГЕННОЙ НАГРУЗКИ НА ОСНОВЕ МОЛЕКУЛЯРНО-ГЕНЕТИЧЕСКОЙ ОЦЕНКИ ПОЛИМОРФИЗМОВ І И ІІ ФАЗ ДЕТОКСИКАЦИИ

Relevance. Adverse environmental conditions and man-made disasters are not considered as air, soil and groundwater oversaturated environmental pollutants and toxicants. They cause disturbances in biochemical reactions and metabolic processes in childhood and at a young age. The aim of this study was to determine the effect of polymorphism of the detoxification gene of the first phase Cyp1A1 (A1506G) and the second phase genes GSTM1, GSTT1, on hard tissue indices of permanent teeth, periodontal indices and oral hygiene indices in children living in areas of different anthropogenic stress. Materials and methods. We studied the polymorphism of the CYP1A1 gene (A1506G), polymorphisms GSTM1, GSTT1 in children living in areas of different anthropogenic stress. We evaluated the state of hard tissues of teeth, periodontal tissues and oral hygiene. Findings. The results of a study of the dental status of children indicate a negative effect of polymorphisms of the GSTM1, GSTT1 genes on the state of hard tissues of teeth, periodontal tissues and oral hygiene, especially as a result of adverse environmental factors. To reduce the likelihood of adverse factors provoking the development of major dental diseases, it is necessary to develop prevention methods based on the study of hereditary predisposition to them.

Analysis of dental morbidity of persons of an organized team in unfavorable working conditions

The prevalence of diseases of the oral cavity in military personnel serving under the contract at various altitudes above sea level in Dagestan was estimated. The working conditions and the influence of physical environmental factors at the effective temperature in the autumn-winter-spring periods of the year are estimated. Professional activity belonged to the category of works IIb. Labor was assessed as harmful 2 degrees (class 3.2). In the winter season, a critical risk of frostbite of the body at medium temperatures and maximum wind was found at heights of 4 m and 1661 m. In the spring and autumn, a moderate risk of frostbite was noted at all altitudes. Dental diseases were registered in the classes «Neoplasms», «Diseases of the digestive system» and «Injuries and poisoning»; their share in the total structure was 15.03%. In the class «Diseases of the digestive system,» the share of dental diseases reached 80.2%. The group «Caries, its complications and other diseases of hard tissues of teeth» occupied the 1st rank place in the structure of morbidity, which is equal to morbidity in the class «Respiratory diseases». The level of oral hygiene is 2.8 ± 0.2 (very low): the teeth are significantly covered with plaque, leading to the progression of pathological processes. Description of the dental status: KPU index (carious, filled, extracted tooth) is 8.5 ± 0.3. The prevailing indicator was «carious», indicating an active carious process in the tissues of the teeth and the «lag» of the treatment, leading to their removal. Military personnel approached a critical indicator of fitness for professional activity. The need for oral sanitation reached 65.5 ± 7.9%. The share of labor losses for dental diseases of the class «Digestive apparatus diseases» reached 3.2%, excluding separation from duty on the day of treatment, of which there are several. The study proves the impact of adverse working conditions on dental morbidity, the need for their assessment to identify risk factors and develop preventive measures.

RESULTS OF TREATMENT OF EDENTULOUS PATIENTS WITH DENTURES MADE OF «FTORAX»

Background. The problem of providing high-quality dental care to edentulous patients remains one of the most important and unresolved to this day in the clinic of prosthodontics. The causes of complete loss of teeth can be both periodontal tissue diseases and diseases of hard tooth tissues of carious and non-carious origin, trauma and the like. It becomes necessary to fabricate complete removable dentures to prevent the occurrence of pathologies in such situations. Complete secondary adentia leads to a large number of local and general complications. The chewing apparatus undergoes a number of functional and morphological changes. Therefore, the complete absence of teeth sets the dentist the task of restoring the functions of full chewing, the appearance of the patient, and speech. The complexity of high-quality prosthetics for edentulous patients is also because the clinical characteristics of supporting tissues are diverse, constantly changing, so a personal approach to creating stable denture is needed. It should be added that the fabrication of high-quality complete removable dentures largely depends on the properties of the base material. The main group of materials for the fabrication of such dentures is acrylic plastics.
 The aim. The work is focused on the study of the functional state of the masticatory muscles and the restoration of masticatory effectiveness in edentulous patients, for whom dentures were made in the prosthodontics clinic from the acrylic base material «Ftorax».
 Material and methods. Hot curing plastic based on fluorine-containing acrylic copolymers «Ftorax» was used in the work. Our evaluation of the quality of all constructions was carried out using the «BOFSAS» test, determining the biopotentials of the masticatory muscles using electromyography, and determining the masticatory effectiveness according to I.S. Rubinov.
 Results. Based on our work, it can be noted that the use of the basic acrylic material «Ftorax» allows us to achieve good fixation and stabilization of complete removable dentures, which is subjectively confirmed by the «BOFSAS» test, objectively – by the electromyographic studies and time indices during chewing test according to I.S. Rubinov.
 The amplitude during volitional compression is 556.90±8.72 μV, which approaches the norm (641.58±10.01 μV), and almost four times higher than before prosthetics (188.11±8,13 μV) after 1 year of constructions using. A similar pattern is observed with arbitrary chewing: the amplitude (547.32±8.43 μV) approaches normal (643.92±9.11 μV) compared with the results before prosthetics (201.40±9.39 μV). As for the coefficient «K», its value decreased almost twofold compared with the results before prosthetics (2.44±0.14) and equals to 1.25±0.03, which is significantly closer to normal (1,02±0.01).
 After the test by Rubinov the following results were obtained: the average time that patients with intact dentitions spent chewing on the stimulus was approximately 12.97±0.13 seconds and the average time for patients before prosthetics (with old dentures) was approximately 45.16±0,41 sec.
 The time that patients spent chewing a nut after 1 month was 28.97±0.42 seconds, after 6 months – 26.94±0.44 seconds, and after 1 year of using the entures – 25.48±0.45 sec.
 Based on this, it can be summarized that adaptation to such dentures takes place at the appropriate time with minor corrections.
 Conclusion. The results of our clinical study indicate the feasibility of using «Ftorax» in prosthodontics clinic for treatment of edentulous patients.

The influence of storage temperature on fracture behavior of cryopreserved teeth-An in vitro study.

ObjectivesCryopreservation is discussed as a viable method of preserving teeth for determined autogenous tooth transplantation. Unchanged physical properties of hard tooth tissues are crucial for functional healing. Due to different thermal expansion coefficients of enamel and dentin or the crystallization process, the freezing process may lead to crack formation, which could adversely impact the long‐term prognosis of the teeth.Material and methodsTwenty third molars (n = 20) were frozen slowly using a conservative cryopreservation protocol and stored at −80°C (group 1) and −196°C (group 2). After a storage time of 2 weeks, the samples were thawed to a temperature of +36°C and embedded in polymethyl methacrylate blocks. Cyclic loading was carried out using a spherical steel test specimen with 50,000 mechanical load cycles, followed by load to failure testing for determination of critical load.ResultsNo significant difference in the first load drop could be detected during the load to failure test under different storage conditions. The values until fracture correlated very closely in contralateral tooth pairs, which emphasizes the importance of crown geometry in load to failure tests.ConclusionsConclusions: Cryopreservation, specifically the storage temperature, does not appear to have a significant effect on the physical properties of tooth transplants.

Features of basic indicators of oral fluid in children after hematopoietic cell transplantation (pilot study)

Relevance. Treatment of patients with refractory forms of acute lymphoblastic leukemia causes a number of complications from the organs and tissues of the oral cavity. It can be both early complications – cytotoxic reactions with the development of oral mucositis, and late, leading to a violation of the mineralization of hard tooth tissues, and to underdevelopment of the teeth. Oral fluid plays an important role in maintaining oral homeostasis. One of the most important functions that it performs is maintaining the physiological balance of the processes of re- and demineralization of tooth enamel. Since demineralization processes begin in childhood at higher pH values than in adults, when the hydrogen index decreases below 6.4, demineralization processes begin to prevail over remineralization, and the solubility of hydroxylapatite crystals which enamel consists of increases.The objective was to assess the basic indicators of oral fluid and oral hygiene indices in this group of patients.Methods and materials. During the examination of the oral cavity, the intensity of caries and hygiene indices were determined. For the study, oral fluid was collected, followed by determination of its viscosity and hydrogen index.Results. These patients showed a lower level of oral fluid hydrogen index and a lower level of oral hygiene compared to healthy children. In addition, during the study, it was found that there is a direct relationship between the pH of the oral fluid and the time elapsed since the hematopoietic cell transplantation.Conclusion. The detected changes are factors that predispose to an increase in the intensity of caries, and require early preventive measures.Authors declare no conflict of interest.The authors confirm that they respect the rights of the people participated in the study, including obtaining informed consent when it is necessary, and the rules of treatment of animals when they are used in the study. Author Guidelines contains the detailed information.

Морфологическое строение твердых тканей зубов у взрослых людей разных возрастных групп с чувствительным дентином

The objective of the experiment is to investigate the morphological structure of dental tissues in people of different age groups suffering from tissue hyperesthesia. Materials and methods. The morphological structure was studied by scanning electron microscopy. We studied 57 teeth that had been removed for medical reasons in 45 adults. With the help of microscopy, hard tissues (enamel, dentin and cement) of teeth were studied. The study involved intact and pathologically altered teeth. Intact teeth were removed for orthodontic indications. In older people, removal was performed due to exacerbation of chronic periodontitis and periodontitis. Results. The revealed morphological changes in dentin are due to the main pathology: whether hyperesthesia is associated with the loss of tooth hard tissues or developed without it. Non-carious lesions of hard dental tissues (erosion and wedge-shaped defects) during morphological examination are caused by a violation of the integrity of the cement, cracks and chips of enamel. It was found that in patients the increased tooth sensitivity and morphological changes develop due to the presence of carious and non-carious processes in the dentin and are independent of gender and age. Conclusion. Both in the carious process and in non-carious lesions of the teeth, no relationship was established between the severity of hyperesthesia of the teeth and the degree of obliteration of the dentinal tubules.

Improving the effectiveness of tooth preparation by using alternative methods

Summary. Preparation of hard tissues of teeth is an integral stage of the invasive method of treating caries and is a complex effect of various factors that make it possible to remove tissues affected by this process and the formation of a cavity of arbitrary shape, based on the principles of gentle preparation, which consists in the most effective removal of demineralized with the preservation of intact tissues.
 The aim of the study – determination of enamel and dentin surface aspects when using ultrasonic type of odontopreparation compared with the preparation of teeth with rotary instruments.
 Materials and Methods. Intact retinal teeth of the chewing group, removed by surgical indications, were used as material for the morphological study. After special preparation, the teeth were dissected using ultrasound with the help of special nozzles and in the classical way using rotary instruments, subject to the protocols of manipulations. Subsequently, histological preparations of these teeth were made and examined by light microscopy at magnification x 400.
 Results and Discussion. In the case of ultrasound preparation, single invaginations were visualized on the surface, which were dissociated by prongs and equal sections of dentin. The tips of dentin prongs are smoothed, the taper is about 800. The maximum height of the prong does not exceed 1.3 microns. In the area of the bottom and walls of the cavity all over the existing lubricated layer in the form of a thin structureless weakly basophilic line, smaller in area compared to the same in the cavity, prepared with rotary tools. At preparation with rotary instruments, small invaginations alternating with pronounced prongs were observed at the bottom and walls. Flat levels were not visualized. The taper of the prongs is about 600 the maximum height of the prong is 2.4 microns. In the region of the bottom and walls of the cavity along the boundary of the preparation, a structured layer is smeared in the form of a thin sharply basophilic line.
 Conclusions. The comparative characterization of dental preparation methods makes it possible to recommend an ultrasound method as a method of choice for a specific contingent of individuals, since it not only provides painless preparation and minimizes stress during dental procedures, but is also gentler on the morphological characteristics of hard dental tissues.

АНАЛИЗ РАСПРОСТРАНЕННОСТИ ПАТОЛОГИИ ТВЕРДЫХ ТКАНЕЙ ЗУБОВ У РАБОТНИКОВ ЗАКРЫТОГО ПРОМЫШЛЕННОГО ПРЕДПРИЯТИЯ

Subject. The analysis of the results of a clinical examination of workers of the special economic zone "Alabuga" of the Republic of Tatarstan on the prevalence and intensity of diseases of hard tissues of the teeth is carried out. The goal is to determine the prevalence and intensity of diseases of hard tissues of teeth among workers in an industrial enterprise. Methodology. The study was conducted using clinical dental examination and statistical analysis of the data. All the subjects were divided into the main group, which included 370 employees of the SEZ "Alabuga" of the Republic of Tatarstan, and a comparison group — 297 people of the same age group working at JSC Chemical Plant named after L.Ya. Karpova "(Mendeleevsk). Dental status of workers was determined by the KPU index and the USP group index (level of dental care). Results. The results of the examination of the state of the oral cavity in the main group and the comparison group of workers in industrial enterprises showed certain differences. A comprehensive dental examination of the studied contingent of the SEZ “Alabuga” revealed a high prevalence of pathology of dental hard tissues. The prevalence rate of dental caries was 100 % at an intensity of 2.1, which corresponds to a high level of intensity according to WHO. Nosological forms of non-carious lesions of the hard tissues of the teeth were more common than in the control group: tooth pigmentation and plaque were diagnosed — in 81.4 % of cases, wedge-shaped tooth defects — in 34.8 %, hyperesthesia — in 32.7 %, and pathological tooth abrasion — in 32.4 %. Conclusions. The clinical study allowed us to identify areas for improving the provision of dental care and preventive measures to employees of individual industrial sectors.

ФИССУРНЫЙ КАРИЕС: ПРОФИЛАКИЧЕСКИЕ АСПЕКТЫ КУРАЦИИ В УСЛОВИЯХ ШКОЛЬНОГО СТОМАТОЛОГИЧЕСКОГО КАБИНЕТА

Subject. The problem of fissure caries remains one of the key in modern cariesology. For individual prevention, the most effective is the method of sealing fissures and fossae of the surface of the teeth. By sealing (sealing) fissures, the creation of a physical barrier for cariogenic factors and microbial plaque, remineralization of hard tooth tissues is achieved.
 The goal is to evaluate the effectiveness of fissure sealing in 9-year-old children living in Kazan.
 Methodology. The study was conducted using the clinical method and statistical analysis of the data. In total, 137 children aged 9 years old, studying in the third grades of the gymnasium No. 102 of Kazan, took part in it. The main group included 82 schoolchildren who performed non-invasive fissure sealing (the first permanent molars) with UltraSeal XT plus sealant, the comparison group consisted of 55 students who did not have fissure sealing.
 
 Results. After 12 months, out of 165 teeth previously coated with sealant, sealant on 95 teeth was completely preserved (57.6 % of cases), sealant fell out or partially retained (tooth is intact) in 36.4 %, fissure caries at the place of sealant was detected in 6.1 % The effectiveness of fissure sealing, which consists in maintaining a healthy masticatory surface of hard tooth tissues, after 12 months of follow-up was 91.9 % with a reduction of caries of 76.7 %. A comparison of the data clearly showed that the condition of the first molars, which was used to seal the fissures, allows us to talk about the preservation of intact fissures in 88 % of cases, while 56 % of unsealed molars are prone to caries of fissures and only 44 % remain intact after a year.
 Conclusions. A clinical study confirms that sealing fissures is a reliable and reasonable method for the prevention of fissure caries.

ИЗУЧЕНИЕ НАРУШЕНИЙ СТОМАТОЛОГИЧЕСКОГО СТАТУСА У МОЛОДЫХ ЛЮДЕЙ, ЗАНИМАЮЩИХСЯ САМОСТОЯТЕЛЬНЫМИ ВИДАМИ ФИЗИЧЕСКИХ НАГРУЗОК С ОТЯГОЩЕНИЕМ

Subject. Violations of the dental status in males involved in the gym for 3-4 years.
 The goal — is to study the peculiarities of the dental status of young people engaged in physical exercises with weights in the gym, for the further development of a set of preventive and therapeutic measures.
 Methodology. The study involved 28 males aged 20 to 29 years, engaged in the gym for 3-4 years with a frequency of visits 3-4 times a week.
 The prevalence of the inflammatory process in the gums was determined using PMA indices in modification and KPI. Acid resistance of tooth enamel was evaluated using an enamel resistance test. Palpation and auscultation of the temporomandibular joint, as well as its functional assessment using the diagnostic complex "Lira-100". The following indicators of mixed saliva were determined: secretion rate, viscosity (by the simplified Redinova—Pozdeev method) and Ph. A functional study of the masticatory muscles was performed using surface electromyography.
 Results. In 14 examined patients engaged in sports exercises with large weights, increased generalized abrasion of hard tooth tissues was revealed, in 8 — localized.
 An index assessment of periodontal tissues confirmed the presence of pathological changes. Dysfunctional disorders in the temporomandibular joints were detected in 20 of 28 amateur athletes (71 %). In young people engaged in bodybuilding, the background activity of the masticatory muscles in a state of functional tension indicates an inconsistent function and asymmetric work of the masticatory muscles.
 Conclusions. As a result of the study, in the majority of examined patients non-carious lesions of hard tooth tissues in the form of increased abrasion, more often generalized, and functional disorders of the temporomandibular joints and chewing muscles, in some cases inflammatory changes in periodontal tissues, were revealed.

Визначення оптимальних індивідуальних параметрів суцільнолитих штифтово-куксових конструкцій за допомогою комп´ютерної програми при лікуванні пацієнтів з дефектами твердих тканин зубів

Визначення оптимальних індивідуальних параметрів суцільнолитих штифтово-куксових конструкцій за допомогою комп´ютерної програми при лікуванні пацієнтів з дефектами твердих тканин зубів

P790 Dental caries occurrence among patients with inflammatory bowel disease (IBD)

Abstract Background Inflammatory bowel disease (IBD), including patients’ diet, way of treatment and general health may have an impact on teeth condition. Due to multifactorial nature of caries that its linked to susceptibility of hard tooth tissues, cariogenic microorganisms and presence of fermentable carbohydrates, the course of disease can be modified at many levels. The aim of the study was to assess dental caries experience in adult patients with Crohn’s disease (CD) and ulcerative colitis (UC). Methods The study involved 224 individuals: 98 with diagnosed CD, 75 with UC and 51 of control group (CG) with mean age 34.7. The complete assessment of the hard tooth tissues based on the DMFT index (decayed D, missing M, filled F teeth) was performed. Results There were no statistically significant differences between the examined groups in terms of DMFT index values, however, a statistically significant difference was found in the number of teeth with caries (D) (mean 3.99, 3.05 and 1.96 for CD, UC and CG respectively; H=13.55 p < 0.05). All groups had higher mean D values in men than women, and achieved the highest mean value in CD group (4.78) compared with UC (3.68) and healthy controls (2.06)(H=8.71 p < 0.05). The results of D values for CG obtained in our study confirm the literature data for healthy population aged 35–44 in Poland (mean D~2). The number of lost teeth (M) in the studied population was high and amounted to 5.47, 5.25 and 3.94 for the examined groups, respectively. A thorough analysis showed that in the group of men the difference in the M value was statistically significant at 5.83, 5.94 and 1.11 for CD, UC and CG respectively (H=15.84 p < 0.05). Statistically significant differences (H=6.21 p < 0.05) were observed in the number of filled teeth (F), without secondary caries, which highest value was recorded in CG (10.76) and the lowest in the CD group (8.93). Conclusion The highest D and M values were observed in patients with CD, especially in men, which proves the intensity and activity of dental caries disease in this group.

ODONTOLOGICAL EFFECTS OF IONIZING RADIATION (review).

Odontological effects of ionizing radiation (IR) as a result of radiotherapy, the consequences of accidents at nuclear power plants and industry, individual occupational exposure, etc. deserve significant attention interns of radiation medicine and radiation safety. to analyze and summarize clinical and experimental data on the odontological radiation effects. the pathological changes in the hard tissues of teeth, pulp, periodontium, mucousmembranes of the mouth and jaws due to exposure to IR. search in the PubMed / MEDLINE, Google Scholarabstract medical and biological databases, scientific libraries of the relevant sources of scientific information. Radiobiological effects of IR due to its direct and indirect action are manifested throughout the period ofodontogenesis and formation of the facial skeleton. Experimental and clinical data (in children and adults) indicatethe increased risk of dental caries, reduction of pain threshold and vascularization of tooth pulp along with its fibrosis and atrophy, periodontal dysfunction, which predispose to a high probability of tooth loss. Abnormalities in theactivity of osteoblasts and cementoblasts of dental periosteum and osteoblasts of alveolar process in combinationwith circulatory disorders due to endothelial cell death, hyalinization, thrombosis and vascular obliteration increasethe risk of jaw osteoradionecrosis. Children who have undergone a prenatal exposure to IR as a result of theChornobyl NPP accident have a premature change of teeth. Deterioration of periodontal tissues and early development of acute and complicated dental caries are typical for children and adults affected by the Chornobyl disaster. Summarized data on the effects of radiation exposure under different conditions on teeth primordia(i.e. immature teeth), their formation and eruption in experimental and clinical settings, as well as on the odontological radiation effects in adults are summarized. Condition of the teeth in the Chornobyl NPP accident survivorsis described. Understanding and taking into account the radiobiological odontological effects is necessary in thelight of planning, preparing, and conducting local radiation therapy and developing the standards of radiation safety and measures to protect professionals and the public in the event of possible radiation accidents at the nuclearpower plants and industry facilities.

The results of evaluating the degree of influence of human blood plasma on the strength of adhesion of composite material to dentin (one-component adhesive system)

To study the dynamics of changes in the adhesion between the composite and dentin of the tooth when using different volumes of a single-component adhesive system in case of contamination of it with human blood plasma. To achieve this goal, the following were used: extracted human teeth, XP Bond one-component adhesive systems (DENTSPLY, Germany), Esthet X HD micrometric restoration material (DENTSPLY, Germany), and centrifuged blood plasma. The strength of the adhesive bond between the composite material and the hard tissues of the tooth was studied using a shear test machine Zwick Roell Z 010 («Zwick», Germany). The use of a single-component adhesive system in an amount of 17.7 mg (1 drop from a dispenser) for treating open dentin makes it more resistant to contamination compared to using the same adhesive, but in an amount of 6.6 mg (the amount of adhesive that adsorbs a medium-sized dental take). A decrease in the adhesion force between the composite material and tooth hard tissues from 1.5 to 17.7% occurs when a single-component adhesive system weighing 17.7 mg of blood plasma simulating a dentinal fluid weighing from 0.2 to 2.0 mg enters. The ingestion of the same amount of blood plasma in a single-component adhesive system weighing 6.6 mg leads to a decrease in its adhesion from 4.3 to 43%.

ORAL HYGIENE IN CHILDREN WITH DISTURBANCES IN TOOTH FORMATION WHO WERE AFFECTED AS A CONSEQUENCE OF THE ChNPP ACCIDENT.

evaluation of oral hygiene to enhance the prophylaxis of complications specifically of dental caries inchildren with disturbances in tooth formation (DTF) who live on radiologically contaminated territories after theChornobyl NPP (ChNPP) accident. Children aged 6-14 years (n = 1470) with DTF were the study subjects examined in 2012-2016. Among them there were (n = 528) residents of the zones III and IV of radiological contamination after theChNPP accident with 137Cs soil contamination density 1-15 Ci/km2. The effective radiation dose in them was notexceeding 1 mSv/year. The Green-Vermillion and Silness-Loe oral hygiene indices were assesses within clinicalexamination methods. The worth oral hygiene was revealed in children having got the DTF, compensated chronic diseases oforgans and systems, and in those with burdened radiation history. The Green-Vermilion and Silness-Loe indices were1.7 ± 0.51 and 1.65 ± 0.46 respectively. A significant deterioration in oral hygiene confirmed by the highest values of the Green-Vermillion index (1.7 ± 0.51; p < 0.001 - «unsatisfactory oral hygiene» criterion) and Silness-Loe index (1.65 ± 0.46; p < 0.001 -«poor oral hygiene» criterion) was found in children with DTF aged 6-14 years being residents of contaminated areasas a result of the Chernobyl accident. The revealed deterioration may be due to a set of negative factors, includingthe impact of ionizing radiation in low doses and peculiarities of social status. Results of the questioning of surveyed pediatric contingents both having got an DTF and with no defects of the hard tissues of teeth indicate aninsufficient level of knowledge and skills in hygienic care of oral cavity regardless of the area of residence.Development of a set of measures to prevent the DTF complications in children should be carried out taking intoaccount the state of oral hygiene, level of knowledge and skills in oral care, and include the use of hygiene products, namely toothpastes and anti-caries mouthwashes.

Устранение дисколорита зубов фронтального отдела верхней челюсти с использованием современных фотокомпозитных материалов

The problem of hard tissues of teeth discoloration treatment is relevant for modern practical dentistry due to the widespread use of endodontic treatment of anterior teeth, dental preservation operations and therapeutic treatment of caries and non-carious lesions of hard tissues of teeth. Teeth discoloration quite often happens as a complication of endodontic treatment, injuries, secondary caries and other lesions of hard tissues. The article describes a clinical case of the removal of discoloration of the front teeth of the upper jaw (after a tooth-preserving operation and previously performed tooth restorations) using the modern photopolymer composites material «Jen-Radiance» and «Jen-Favorite LC» made in Ukraine.