[Lower jawbone structures symmetry evaluation using cone beam computed tomography]

OBJECTIVE

To assess the prevalence and quantitative characteristics of skeletal asymmetries of the body and lower jaw branches in three-dimensional space.

MATERIALS AND METHODS

Using depersonalized data archive, of 400 CBCT scans, forty studies were picked randomly. Patients aged 25 to 35 years participated in research, no history of maxillofacial reconstructive surgery; gender, race, and facial anomaly were ignored. Three experienced doctors, independently, identified 15 reference points on radiographic images of AUTOPLAN software. Expert consensus found in the orientation determination. Six planes and eight points were constructed, using Math algorithms and the Python OOP; body and branches of the lower jaw length measurements performed and processed automatically.

RESULTS

The study identified symmetry, using a method for determining parameters of the lower jaw in 3D space (Priority Reference No.2023100466 at 10.01.2023), modern dentistry research method. Both sides of data obtained shown asymmetry of the body and branches of the lower jaw occurred in 45% (18 people) and 67.5% (27 people) of cases. Forty percent of cases were noted with Mild asymmetry of the lower jaw body (16 people), moderate asymmetry noted in 5% (2 people). These parameters were 57.5% for branches, (23 people) and 10% (4 people). Combined form of anomaly observed in 37.5% (15 people) of cases, among which 12 people (75%) showed adaptive compensation of anomalies, which requires further investigation on a larger number of patients.

CONCLUSION

Lower body jaw asymmetry is prevalent (80%). Patients with moderate and serious anomaly form appeared in 15% of cases.

[Oral hygiene and microcirculation of the mucous membrane of the tongue and gums dynamics in patients with burning mouth syndrome as a result of the use of a toothbrush with a gold-zinc electroplating]

THE AIM OF THE STUDY

Was to assess the level of oral hygiene and microcirculation of the mucous membrane of the tongue and gums in patients with burning mouth syndrome (BMS) as a result of using a toothbrush with a gold-zinc electroplating.

MATERIALS AND METHOS

The study included 50 patients of both sexes aged 45-64 years with the diagnosis of BMS divided into two groups. In the main group, the complex of hygienic measures included the use of a toothbrush with a gold-zinc electroplating and a paste with the fluorine content of 1350 ppm. In the comparison group, a regular manual toothbrush and a paste with a fluoride content of 1350 ppm were used for oral hygiene. A control group consisted of 25 healthy people with the mean age of 44±4.5 years without clinical signs of BMS in the oral cavity and concomitant acute somatic pathologies.

RESULTS

Tongue mucosa microcirculation level in patients using the toothbrush with a gold-zinc electroplating was significantly higher than in the comparison group using conventional manual toothbrush. Oral hygiene level assessment showed statistically significant better brushing efficacy in patients using the toothbrush with a gold-zinc electroplating.

CONCLUSION

The use of a toothbrush with a gold-zinc electroplating contributes to the normalization of microcirculation in the mucous membrane of the tongue and gums and is recommended for inclusion in the complex of therapeutic measures in patients with BMS.

[Cephalometric analysis of lateral skull X-ray images using soft computing components in the search for key points]

THE AIM OF THE STUDY

Was to investigate the efficiency of decoding teleradiological studies using an algorithm based on the use of convolutional neural networks - a simple convolutional architecture, as well as an extended U-Net architecture.

MATERIALS AND METHODS

For the experiment, a dataset was prepared by three orthodontists with over 10 years of clinical experience. Each of the orthodontists processed 100 X-ray images of the lateral projection of the head according to 27 parameters, 2700 measurements were made. The coordinates of the control points found by orthodontists in the images were compared with each other and a conclusion was made about the consistency of experts in the data obtained.

RESULTS

The results of convolutional neural network CNN were not satisfactory in 17 (62.96%) features, satisfactory in 10 (37.04%). The assessment of orthodontists resulted in non-satisfactory evaluation in 6 (22.22%), satisfactory in 8 (29.63%), good in 8 (29.63%), and excellent in 5 (18.52%) coordinates. Neural networks with U-Net architecture showed satisfactory results in 9 (33.3%) cases, good in 16 (59.3%) and excellent in 2 (7.4%) cases, with no non-satisfactory results.

CONCLUSION

The neural network of the U-Net architecture is more effective than a simple fully convolutional neural network and its results of determining anatomical reference points on two-dimensional images of the head are relatively comparable with the data obtained by medical specialists.

[Experimental study of the bearing capacity of lyophilized allogeneic bone material]

THE AIM OF THE STUDY

Was to conduct an experimental study of the bearing capacity and determination of the Young's modulus of lyophilized allogeneic bone material.

MATERIALS AND METHODS

The study used 5 prototypes of lyophilized allogeneic bone blocks, which were alternately subjected to static loading by compressive force. The experimental values of Young's modulus of all bone samples were determined. When applying the Student's probability distribution in statistical processing of experimental data, the average indicators of the forces of destruction of the samples were obtained and Young's modulus was determined.

RESULTS AND DISCUSSION

As a result of the study, the indices of the maximum loading (6012H) and Young's modulus (147.2±0.228 MPa) of lyophilized allogeneic bone material were obtained.

CONCLUSION

The obtained Young's modulus of lyophilized allogeneic bone material is of great importance in scientific activity, providing the possibility of further investigation of the properties of lyophilized allogeneic bone tissue to form a preoperative forecast of the behavior of an osteoplastic material and a dental implant installed in it.

Analysis of osseous tissue temperature during preparation of recipient bed for cylindrical implants

In the early 21st century, robot-assisted dental implant surgery became a popular alternative to classic implant placement protocols. Postoperative complications are often provoked by poor compliance with surgical guidelines for implant placement, resulting in the overheating of the osteotomy site. The aim of this study was to measure the temperature of osseous tissue at the dental implant site during classic and robot-assisted dental implant placement performed at different cooling modes. Avital skeletonized mandibles of Vietnamese pot-bellied pigs were used as an experimental model. The recipient bed was prepared following the classic surgical protocol. Three cooling modes were tested: no irrigation, irrigation with sterile saline at 25–30 ml/min and standard 75 ml/min irrigation recommended by the standard surgical protocol. The temperature of the isotonic solution was 25 °С. The study showed that both classic and robot-assisted dental implant placement techniques are safe if there is sufficient irrigation and good compliance with the surgical protocol.

[Consistency of expert opinions on localization of the reference points for studying a soft tissue face profile in digital teleradiological images of the skull lateral projection]

OBJECTIVE

The aim of the study is to identify the consistency of expert opinions when manually identifying the reference points positions for studying the soft-tissue face profile in digital teleradiological images of the skull lateral projection.

MATERIAL AND METHODS

The study involved 11 orthodontists having a 1 to 8 year experience. They localized the reference points manually, using the software with image enhancement options. Each doctor processed 100 X-ray images of the skull lateral projection. Totally, 1100 positions were identified (11 parameters in 100 images). The average position of 11 manual localizations was taken as the baseline. Then, manually identified positions were automatically compared with the basic localization.

RESULTS

We have a good consistency of expert opinions when determining the reference points of the soft-tissue face profile. Herewith, the highest consistency of expert opinions is observed for soft-tissue reference points of the upper and lower lips (LL and EN points) with the average variation coefficients equal to 0.557726 and 0.566349 respectively; and the lowest consistency is observed for the hard tissue point Po with the average variation coefficient of 0.819904. Despite rather serious shortcomings in determining separate points (such as Or, DT, Po) in teleradiological images of the lateral skull projection, the method for determining soft-tissue profilometric reference points gives satisfactory results for more than 85.87% cases. In general, the method can be considered clinically reliable. However, the means and methods for identifying reference points require improving.

[Technology of manufacturing of personalized reconstructive allogenic bone graft (in Russian only)]

AIM

To develop the technology of manufacturing of reconstructive allogenic bone graft with individual parameters by using of digital prototyping and modeling.

MATERIAL AND METHODS

Allogeneic cadaveric bone blocks were used as material. The following methods were used to develop a manufacturing technology for personalized allogenic reconstructive bone implant: harvesting and special preparation of cadaveric material, primary disinfection, viral inactivation, ultrasound management, lyophilization of bone material, CT-examination of patients with various bone defects, digital prototyping and modeling, milling on a machine with numerical program control, X-ray sterilization.

RESULTS

The technology of manufacturing of reconstructive allogenic bone graft with individual parameters was successfully tested in the treatment of 24 patients with post-traumatic, destructive-dystrophic and degenerative defects of jaws in 2012-2015. Final reconstructive allogenic bone implant has a personalized 3D-geometry in accordance with individual maxillofacial anatomy of particular patient. One of implant surfaces is fully congruent to the jaw bone defect, the others form the width, height and volume of reconstructive bone implant considering personified maxillofacial features. All above-mentioned features of bone implant are important to restore chewing function of dental system.

CONCLUSION

The problem of bone implant personification may be resolved by using of computed tomography followed by digital analysis of jaw structure, technologies for digital reconstruction of bone defects (digital prototyping and modeling) and digital manufacturing.

[Estimated error of bone digital solid 3D-model construction algorithm]

The aim of the study was an experimental estimation of precision of maxilla bone digital solid 3D-model construction algorithm. The experiment was carried out on 12 mutton mandibles used 3D-model construction based on CT data. Estimated error was calculated for each of the stages of proposed processing algorithm including 3 software: ScanIP (triangle mesh calculation, primary solid 3D-model), ArtecStudio 9 (secondary procession for artefacts elimination), ZBrush 4R6 (triangle mesh simplification, final 3D-model). The proposed algorithm provides satisfactory precision for solid 3D-model with individual maxillary bone features.

[Preclinical tests of additive materials for personified endoprostheses of hand joints]

AIM

To evaluate the biocompatibility of additive materials for personified endoprostheses of hand joints in vivo.

MATERIAL AND METHODS

We tested a material based on titanium that was implanted into muscles and bone tissue in experiment on rabbits. Follow-up was 30 and 90 days.

RESULTS

Implantation into muscle tissue is accompanied by reaction against foreign body followed by fibrosis without concomitant inflammation. Induction of osteogenesis and trabecular structures remodeling were detected after implantation into bone tissue.

CONCLUSION

Biocompatibility of tested titanium-based material was confirmed.

REVIEW OF EPIDEMIOLOGIC SITUATION ON HEMORRHAGIC FEVER WITH RENAL SYNDROME (HERS) IN RUSSIAN FEDERATION IN 1990 - 2015

AIM

Analyze HFRS morbidity in Russian Federation during the last 25 years (1990 - 2015).

MATERIALS AND METHODS

Official statistics of Federal Service for Surveillance on Consumers' Rights Protection and Human Weillbeing (CPS), including Federal Centre of Hygiene and Epidemiology, were used for the analysis, as well as materials from regional departments of CPS and centers of hygiene and epidemiology. Epidemiologic analysis was the main method. Statistical treatment of the results obtained was carried out using gener- ally accepted methods of variation statistics with elements of system analysis. Results; For the studied period (1990 - 2015) 194 116 cases of HFRS were registered. Morbidity was registered in 8 federal districts of the Russian Federation in 58 subjects. The most intense epidemiologic situation was noted in Privolzhsky Federal District, that accounted for 86.4% of total HFRS morbidity during the -studied period. Analysis of morbidity was carried out in every federal district, most epidemically unfavorable territories are shown.

CONCLUSION

The data presented on HFRS morbidity reflect -unfavorable situation for this disease in Russian Federation. Measures to prevent the emergence of diseases to reduce the general level of morbidity in Russian Federation are presented.

[EPIDEMIOLOGICAL DIFFERENTIATION OF NATURAL FOCI OF HEMORRHAGIC FEVER WITH RENAL SYNDROME OF THE REPUBLIC OF BASHKORTOSTAN]

AIM

Typization of natural foci of HFRS of the Republic of Bashkortostan and differentiation of their territories. by the degree of potential epidemic hazard.

MATERIALS AND METHODS

Materials of epizootologic and epidemiologic monitoring of natural foci of HFRS of the Republic of Bashkortostan for 1980 - 2014 were used. Evaluation of area of territory with high, medium and low potential epidemic hazard by HFRS was carried out taking into account multi-year param- eters of morbidity by administrative districts of the Republic of Bashkortostan. 3 gradations of morbidity level by HFRS - more than 201, 101 - 200, less than 100 per 100 thousand of the population - were used for epidemiologic differentiation ofthe territory.

RESULTS

3 main landscape- epidemiologic types of HFRS foci were isolated - forest, forest-barrens, barrens, as well as their landscape variants. The area with a high degree of potential epidemic hazard by HFRS was estab= lished to be around 3.8%; medium - 15.9%, low - 80.3%.of the whole territory of the Republic of Bashkortostan.

CONCLUSION

-A necessity of a differentiated approach to territories with various degree of potential epidemic hazard by HFRS is justified during execution of prophylaxis activi- ties.

[IMPACT OF CASPIAN SEA LEVEL FLUCTUATIONS ON THE EPIZOOTIC ACTIVITY OF THE CASPIAN SANDY NATURAL PLAGUE FOCUS]

There is evidence that in 1923-2014 the sharp aggravations of the epizootic situation of plague in the area of its Caspian sandy natural focus after long interepizootic periods are in time with the ups of the Caspian Sea in the extrema of 11-year solar cycles. There were cases of multiple manifestations of plague in the same areas in the epizootic cycles of 1946-1954, 1979-1996, 2001, and 2013-2014. The paper considers the possible role of amebae of the genus Acanthamoeba and nematodes, the representatives of the orders Rhabditida and Tylenchida in the microfocal pattern of plague manifestations.

[Formation of focus of West Nile fever on the territory of Saratov Region]

AIM

Detection of circulation of West Nile virus (WNV) on the territory of Saratov Region and prerequisites for formation of natural focus of West Nile fever (WNF), determination of the role of WNV in infectious pathology on the territory of the region.

MATERIALS AND METHODS

of organs of small mammals, birds, blood-sucking arthropods for the presence of WNV markers (antigens and/or RNA) were studied. Clinical material from patients with symptoms not excluding WNF was studied. Donor blood sera samples were analyzed with the aim of detection of immune layer against WNV in population of Saratov Region.

RESULTS

In 2010 WNV antigens were detected by EIA in 12 samples (7.1%) of mammal organ suspensions. In 2012 by using RT-PCR and EIA, markers of WNV were detected in 6 samples of bird brain suspensions (6.3%) and 1 sample of mammal organ suspension. Immune layer of population against WNV was 4% in 2011, 2.8% in 2012. In 2012 in 11 of 27 examined patients IgM against WNV in diagnostic titers and/or serconversion of IgG in paired sera were detected. In addition in 5 individuals virus RNA was detected in blood. Based on clinical, laboratory data and epidemiologic anamnesis 11 patients were diagnosed with WNF.

CONCLUSION

The results obtained give evidence on the circulation of WNV on the territory of Saratov Region in 2010 - 2012. With the development of complications of WNF epidemiologic situation in 2012 an expansion of WNV areal onto the territory of the region took place and the process of formation of WNF natural foci is ongoing.

[Improvement of typification of natural foci of plague based on ecological-genetic analysis of Yersinia pestis]

Contemporary features of distribution of various subspecies and biovars of plague causative agent by landscape-geographical zones and mountain belts on the territory of Russia and other CIS countries are examined. The most widely spread in plain and mountain natural foci were noted to be Yersinia pestis main subspecies medieval biovar strains. Strains of Y. pestis non-main subspecies are spread in mountain landscapes of Altai, Caucasus, Tian Shan. Change of dominating species of rodents considered as the main carriers of plague was noted not to result in change of genetic and biochemical characteristics of Y. pestis strains. Perspectives of study of "micro-focality" of plague are emphasized for deciphering the mechanism of the enzootic.

[Reasons of low epizootic activity of natural foci of plague in Russia at the beginning of the 21st century]

AIM

Establish the main reasons of low epizootic activity of natural foci of plague in Russian Federation in 2000-2009.

MATERIALS AND METHODS

Multiyear data on the number of isolated Yersinia pestis strains, area of detected epizootic sites, amounts of the field material studied for plague were used to evaluate annual activity of natural foci.

RESULTS

In the current decade mountain and high-mountain natural foci of plague were characterized by constant high epizootic activity. In plains and low-mountain natural foci a low periodic epizootic activity was noticed, a development of intra-epizootic periods. A conditioning role of helioclimatic factors on the status of parasitic systems and epizootic activity of natural foci of plague was noticed.

CONCLUSION

The warming of climate in 1990-2007 was the main reason for low epizootic activity of plains natural foci of plague in Russia. In the contemporary conditions of a recurrent cooling (from 2008) and an increase of humidity in the Northern, North-Western pre-Caspian and pre-Caucasus territories, a new significant activation of them is predicted there with a peak in 2017-2019.

[Phenomenon of Yersinia pestis biofilm formation in flea organism]

For the first time substantiated was the role of the phenomenon of Yersinia pestis biofilm--extracellular matrix envelope (EME)--formation as the basis that determines the nature of plague agent interaction with flea organism. Implication of vector's proventriculus in the process of biofilm formation was demonstrated. Ultrastucture of plague microbe conglomerates in flea proventriculus and midgut was analysed and uniform mechanism of their formation was elucidated. The role of Yersinia pestis biofilm in plague agent preservation in the gut of ectoparasites and soil of rodents burrows was discussed. PCR analysis confirmed the presence of plague microbe in plague infected corpses and fleas excrements stored at +8-10 degreesC for 7 years 9 months.

[Molecular mechanisms of the plague pathogenic agent interaction with invertebrates]

Microbe Russian Anti-Plague Research Institute, Saratov, Russia The literature data and experimental results of the authors on the molecular basis of plague agent interaction with invertebrates are discussed. The details of the plague agent life cycle, its genome organization, and molecular genetic mechanisms of its survival in flea vector and on the nematode cuticule are discussed. The experimental data about the ability to form biofilms at abiotic and biotic surfaces in the Yersinia pestis strains of the main and non-main subspecies are presented. Mechanisms of horizontal and vertical transmission of plague agent are considered. The suggestion about participation of the new member in the complex parasitic biocenosis (nematode, vector parasite) is put forward.

[The manifestation of necrophagy in the populations of rodents carrying the virus of hemorrhagic fever with renal syndrome]

The role of necrophagy in the epizootic manifestations of hemorrhagic fever with renal syndrome (HFRS) is first shown. By analyzing a great body of data obtained in the Saratov Region in 1982-2000, it has been established that the frequency of manifestations of necrophagy depends on many factors, the most important of which are a season, the size (density) of populations of small mammals, their species composition and the type of biotopes inhabited by these animals. Necrophagy is ascertained to be of great importance in HFRS foci as one of the alimentary routes of infection transmission in the parasitic systems. The presence or absence of necrophagy may serve as a preliminary test for the activity of HFRS foci.

[The clinical picture, diagnosis and radiation treatment principles in cancer of the buccal mucosa]

Diagnosis and treatment of 228 patients with cancer of the buccal mucosa is analyzed. There were 130 women and 98 men aged 65 years on average. 218 were primary patients and 10 with relapses. Squamous-cell carcinomas with hornification predominated: 217 cases (95%). Adenocarcinoma was diagnosed in 8 (3.5%) and poorly differentiated cancer in 3 patients. Metastases to the regional lymph nodes were detected in 25% cases. For cosmetic reasons, radiotherapy (oral x-ray therapy, interstitial method, long-distance gamma beam therapy) was the method of choice.

[A case of Kaposi's sarcoma with involvement of the facial skin and the mucosa of the right cheek]

The authors analyzed the clinical and morphological picture of Kaposi's sarcoma in a patient aged 38 with involvement of the facial skin and right buccal mucosa. Published reports and their own findings brought the authors to a conclusion that such a form of the disease is rare, characterized by specific clinical and morphological features, and difficult to treat. The prognosis is unfavorable because of generalization of the process, the duration of the disease ranging from several months to 20 years.

[A model of multiple contacts, describing the interaction of rRNA sites with mRNA]

A model describing the interaction of a short oligonucleotide with long polynucleotide matrix has been developed. The model allows to calculate possibilities of oligonucleotide binding with different matrix sites on the basis of thermodynamic parameters of duplex formation. The model has been used for description of messenger RNA interaction with "clinger-fragment" sites on ribosomal RNA, which are potential sites of hybridization with mRNA. A possibility of rRNA interaction with mRNA by means of multiple duplex formation between "clinger-fragments" and numerous complementary short mRNA sites is discussed.

[The dynamics of the microbiocenosis in the burrows of the little suslik]

Microbiocoenoses being formed in burrows of little souslik have been investigated. Microbiocoenoses of sloping burrows have most simple organization. Comparative analysis of the fauna and functional structure, conducted during the spring-summer period, has not shown the existence of any directed process in the development of microbiocoenoses of sloping burrows. On the contrary, microbiocoenoses of vertical nest burrows can be regarded as biocoenotic systems dynamic in space and time. Here in the period of rodent's vital activity occurs a constant construction of underground passages and periodical change of nests. In this case the fauna of new nests is formed largely at the expense of migration of nidicols along free or obstructed with loose earth underground horizontal passages. Microbiocoenoses in burrows of different types are not connected between each other by morphoprocess and their development is of independent character.

[Regional metastasis of tongue cancer]

The regional metastases of lingual cancer T1-T4 were studied in 240 patients. In 104 of the cases (48.3%) metastases were found in the lymphatic nodes. The occurrence and the peculiarities of the metastases were assessed with respect to the spreading of a primary tumor, its topography and the variant of anatomical growth. The scheme is presented depicting the position of particular groups of regional lymphatic nodes afflicted and their involvement analyzed. Metastases were directly correlated to the dimensions of a primary tumor. They were more frequent (42.5%) in submandibular and jugular-bigastric lymphatic nodes.

Two-step targeting of urokinase to plasma clot provides efficient fibrinolysis

Two-step targeting of urokinase to a model thrombus (human plasma clot) has been examined in vitro. To this purpose a covalent conjugate of vector antibodies to fibrinogen with monoclonal non-inhibiting antibody to urokinase was obtained using cross-linking agent disuccinimidilsuberate. After pretreatment with the conjugate clot acquired affinity for urokinase, which alters the character of fibrinolysis. Pretreatment with the conjugate resulted in at least 10-fold decrease in dose of urokinase needed for effective clot lysis (from 150 IU/ml for intact clot to 10-15 IU/ml for pretreated one). This variant of urokinase targeting provides effective clot lysis without fibrinogenolysis in plasma.

Monoclonal antibody to human endothelial cell surface internalization and liposome delivery in cell culture

A monoclonal antibody (mAb), E25, is described that binds to the surface of cultured human endothelial cells. Upon binding E25 is rapidly internalized and digested intracellularly. Selective liposome targeting to the surface of the cells is performed using a biotinylated E25 antibody and an avidin-biotin system. Up to 30% of the cell-adherent liposomal lipid is internalized.

[Efficacy of radiotherapy of cancer of the mouth mucosa]

An analysis of 10-year experience of a radiological department (962 patients) indicated late admission of oral mucosa cancer patients for specialized treatment: 75-85% of the patients were admitted with Stage II-IV disease. The assessment of the efficacy of radiotherapy according to the 3 and 5-year survival rates showed that better results were obtained for buccal mucosa cancer and the worst for mouth fundus cancer. Three-year survival rates could be considered sufficient for the assessment of buccal cancer therapy whereas a 5-year period was necessary for the rest of the cancer sites. Therapeutic results and stage were well correlated; in all the sites the results were worse in patients with Stage III-IV disease. Regional metastases are a poor prognostic sign, particularly fixed metastases in patients with tongue and mouth fundus cancer. Combined therapy turned out to be the most effective in tongue cancer. In different variants of dose delivery in time the most favorable results were obtained with small fractionation (a conventional course). However it should be noted that a split course was usually applied to weak elderly patients with advanced stages of disease.

[Level of parasitic contact in colonies of the little suslik in the semideserts of western Kazakhstan]

Field experiments were conducted during the settling of young animals of Citellus pygmaeus in four areas 4 to 13.6 hectares in size. From 3 to 6 animals were caught in each area and labeled by administering radioactive substance (0.5 micrograms of glycine 14C or methionine 35S) and colouring hair on the head. In a day or two labeled sousliks were caught again and in 6-7 days a total catching of animals and collection of ectoparasites from their hair and burrows done. In al, 942 sousliks were caught in the experimental areas and 2624 specimens of fleas of different species and 2305 ticks of R. schulzei collected. The average number of fleas which were labeled on one little souslik for a day was 0.1 to 2.3. The number of labeled fleas in the above areas coincided with the number of fleas infected with plague in the areas of epizootia. The level of parasitic contact in settlements of little souslik cannot provide the development of plague epizootia by transmission of the agent through fleas.