[Bond strength of metal brackets to enamel with a Russian adhesive complex: an in vitro study]. / Sila adgezionnogo soedineniya emali zuba i metallicheskogo breketa, poluchennogo s pomoshch'yu otechestvennogo adgezivnogo kompleksa in vitro.

BACKGROUND: The era of using adhesives to fix brackets began in the 70s of the last century. There are eight generations of foreign-made adhesive systems for the restoration of teeth. However, until now, in orthodontics, the development of domestic adhesive systems with improved properties of adhesion of brackets to tooth enamel still important, especially in the posterior teeth. OBJECTIVE: The purpose of this work was to study the shear strength of fifth generation domestic adhesive between metal brackets and the enamel of molar teeth in laboratory conditions. MATERIAL AND METHODS: The study included 17 specimens of extracted maxillary molars embedded in acrylic resin blocks. Brackets from G&H Orthodontics (G&H Wire Company, USA) were fixed to the tooth enamel using the domestic Compofix (ortho) set. The enamel was treated with etching gel (37% phosphoric acid) for 30 seconds. Then the gel was washed off with water and the surface of the enamel was thoroughly dried. A primer was applied to the prepared surface with an applicator, inflated with a weak air flow for 5-10 seconds and photopolymerized for 20 seconds. The surface of the bracket was treated with degreaser, then a thin layer of adhesive was applied, and the sample was fixed to the enamel. Excess material was removed with an applicator. The samples were photopolymerized for 20 sec. Then, the shear bond strength of the adhesive was determined according to the method of GOST 31574-2012 on a (Zwick/Roell Z010 testing machine, Zwick, Germany). RESULTS: The shear strength of the adhesive joint obtained during the test is 13.54±1.01 MPa, the average value of the index of adhesive residues on the surface of the bracket was 23%±4%, which corresponds to the standard average values according to GOST. CONCLUSION: The tested domestic adhesive system of the fifth generation can be recommended for the practical work of an orthodontist.

[INFLUENCE OF BEVERAGES ON THE DENTOALVEOLAR SYSTEM (EXPERIMENTAL STUDY)].

The aim of the study was to determine the influence of various drinking liquids on an the dentoalveolar system in rats. The study was carried out on 25 white male rats from the nursery of Krolinfo branch of the Moscow region which were kept in standard vivarium conditions. Age of rats-3-6 months, weight - 150-200 grams. The study was carried out in accordance with the ethical principles of humane treatment of animals, in accordance with the current legislation of the Russian Federation. To assess the effect of consumed fluids, groups of 5 animals of the same sex (males, females) were used. The animals were randomly assigned to groups. Observation of animals was carried out for 6 months, during this period the animals were in conditions of free access to food and as drink received the studied liquids ad libitum. Experimental groups within 3 months received the following types of drink: I (control group) - tap water; The II group - Coca-Cola; The III group - honey water; The IV group - the distilled water; The V group - light water. The results obtained by the authors and the data provided in literature confirm that among the factors that affect the teeth condition, in particular the characteristics of the hardness of enamel and dentin, the use of various sugar-containing drinks, as well as the duration, quantity, and frequency of their use, can play a significant role. These factors remain largely unexplored at present. It is obvious that in order to stop caries, it is necessary to develop and carry out a set of preventive measures, including limiting the consumption of sweets and beverages containing sugar, along with regular dental care and a balanced diet.

[Evaluation of the effect of sodium hypochlorite gel on composite bonding strength to enamel of primary teeth after salivary contamination: in vitro study]. / Primenenie gelya gipokhlorita natriya dlya uluchsheniya stsepleniya kompozitnogo materiala s emal'yu vremennykh zubov pri slyunnoi kontaminatsii.

OBJECTIVE: The study investigated the effect of 2%s odium hypochlorite gel application after post-etching salivary contamination on composite bonding strength to primary teeth enamel. MATERIAL AND METHODS: The sample consisted of 79 primary human teeth that were extracted no more than one month ago. The sample was randomly divided into four groups: (1) the control group (A) comprised 10 primary teeth, and composites were applied in the traditional manner without any salivary contamination; (2) the second group (B) consisted of 23 primary teeth in which salivary contamination was conducted after etching followed by re-etching and follow-up; (3) the third group (C) comprised 23 primary teeth in which saliva contamination was done after etching followed by washing, drying, and follow-up; and (4) the fourth group (D) comprised 23 primary teeth, in which salivary contamination was conducted after etching followed by application of sodium hypochlorite gel and follow-up. The samples were tested using the Testometric Tensile Strength Device (Testometric M350-10 kN, Testometric Ltd., UK) to measure the composite bonding strength to enamel of primary teeth. RESULTS: The arithmetic mean strength values in the research sample were ordered as followed: (A=13.39 MPa) > (D=11.82 MPa) > (C=8.07 MPa) > (B=6.15 MPa). The application of sodium hypochlorite gel after salivary contamination significantly improved the composite bonding strength to primary teeth enamel when compared with re-etching or only washing and drying. CONCLUSION: 15 s exposition of sodium hypochlorite gel with subsequent rinse and drying is recommended in case of saliva contamination of etched primary tooth enamel surface.

[Diagnosis and treatment of acute intestinal obstruction due to gall-stone].

Results of treatment of 43 patients with acute intestinal obstruction due to gall-stones are analyzed. Forty patients were operated, 3 patients were not because of extremely severe state. Enterolythotomy was performed in 27 cases, incision of intestinal wall was carried out directly above the stones (14 cases, group 1), above or below it (13 cases, group 2). Insufficiency of enteral suture was seen in 4 patients of group 1 that required repeated surgery. Lethality in group 1 was 21.4%, in group 2-7.1%. Intestinal resection was performed in 12 patients of group 3, there were no cases of suture insufficiency, and lethality was 8.3%. It is concluded that enterotomy should be performed above or below strangulated stone. Intestinal resection should be performed when concrement is immovable or in cases of intestinal necrosis.

[Hormonal disorders in women with prosopalgia in osteochondrosis of the cervical spine and the possible means for their correction]. / Gormonal'nye narusheniia u zhenshchin s prozopalgiiami pri osteokhondroze sheinogo otdela pozvonochnika i vozmozhnye puti ikh korrektsii.

Radioimmunoassay was employed to determine basal levels of LH, FSH, prolactin, total testosterone and 17 beta-estradiol in plasma from 52 pre- or postmenopausal women with prosopalgia consequent to cervical osteochondrosis. The measurements were made before and after laser treatment. Different from the control, basal levels of the hormones and the trends in their changes due to laser therapy depended on the patients' age and the disease stage.

[Interstitial hyperthermia method in spontaneous tumors]. / Interstitsial'nyi metod gipertermii spontannykh opukholei.

To induce hyperthermia of spontaneous tumors in dogs an interstitial method of heating was used: electrodes in the form of injection needles were implanted around tumors. Necessary temperature levels could not be attained in a dog with circumanal angiosarcoma because the tumor was well vascularized and had a considerable volume. No thermal damage of the animals' skin was observed during all sessions of hyperthermia. A conclusion was made that the interstitial method of heating could be used in multimodality therapy of malignant tumors of a complex shape.

[Model study of the structure of heat release when using interstitial hyperthermia on tumors]. / Model'noe issledovanie struktury teplovydeleniia pri primenenii interstitsial'noi gipertermii opukholei.

Heat distribution structures are given with application of the interstitial method of heating with the 1.7 MHz frequency, 8 implanted needles arranged in 2 rows were used as electrodes. Heat distribution structures are obtained on the basis of the mathematical model which was constructed in the electrostatic approximation and with the investigation of the spatial distribution of temperatures in the tissue-equivalent phantom. The results obtained in the both cases coincide.

[Contibution of the X chromosme to the increased resistance of inbred Drosophila melanogaster hybrids to physical effects]. / O vklade X-khromosomy v povyshenie ustoichivosti mezhlineinykh gibridom Drosophila melanogaster k nekotorym fizicheskim vozdeistviiam.

Effects of high sub-lethal temperature and UV-irradiation on surviving of inbred lines of Drosophila melanogaster and its F1 hybrids derived from reciprocal crosses between these lines are investigated. High resistance of F1 hybrids to these factors was observed as compared with that of parental inbred lines. D. melanogaster females in inbred lines and F1 hybrids were more resistant than males. Differences in the resistance between females and males were more pronounced in hybrids.