StomatologiyaPub Date : 2024-01-01DOI: 10.17116/stomat202410303131
A A Stafeev, I A Viktorova, A V Khizhuk
{"title":"[Assessment of the condition of organs and tissues of the oral cavity in people with dentition defects against the background of metabolic syndrome].","authors":"A A Stafeev, I A Viktorova, A V Khizhuk","doi":"10.17116/stomat202410303131","DOIUrl":"https://doi.org/10.17116/stomat202410303131","url":null,"abstract":"<p><strong>Objective: </strong>The aim of the study is comparative analysis of the condition of oral organs and tissues in people with metabolic syndrome (MS) of varying severity before orthopedic dental rehabilitation based on dental implants.</p><p><strong>Material and methods: </strong>255 patients (151 women and 104 men) aged from 35 to 65 years were examined. 3 groups were formed: 2 study groups and a comparison group. Groups 1 and 2 included individuals with excess body weight and MS. The control group consisted of 88 people without MS. An index assessment of the condition of the periodontium and tissue structures of the alveolar bone (according to cone-beam computed tomography), microcirculation in the gingival mucosa was carried out using laser Doppler flowmetry.</p><p><strong>Results: </strong>The analysis of the periodontal condition indicators showed that in all groups of patients with MS, periodontal pathology occurred, the value of which was significantly higher than in patients of the control group (<i>p</i> <0.05). The analysis of bone tissue according to CBCT data showed that the most favorable conditions (type 1 and type 2 of bone according to Misch) for dental implantation are found in people without MS, respectively 3.5% and 35.1% of cases. The intensity of blood flow (σ) was 21.2% lower in group 1 and 48% in group 2, compared with the control group. Vasomotor activity (Kv) was 13.2% lower in the first group and 35% lower in the second group. A decrease in amplitudes in the area of all rhythms in the LDF gram was found: low-frequency - by 15.6%, high-frequency - by 16.9%, pulse - by 3.6%.</p><p><strong>Conclusion: </strong>Changes occurring in the organs and tissues of the mouth against the background of MS of varying severity lead to a decrease in tissue perfusion with blood and blood flow activity, a local decrease in bone density, and as a result, pathological changes in periodontal tissues. Before performing dental rehabilitation, it is necessary to take into account all the risks of possible complications caused by the general condition of organs and systems of people with MS.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"103 3","pages":"31-38"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141433011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2024-01-01DOI: 10.17116/stomat20241030315
A M Tsitsiashvili, A V Volkov, N V Solis-Pinargote, V R Gabidullina, A V Zaborovsky, A M Panin, N V Stankova, P Yu Peretyagin
{"title":"[Determination of the presence of an antibiotic in implant-bone biopsy specimens by Raman spectroscopy in experiment].","authors":"A M Tsitsiashvili, A V Volkov, N V Solis-Pinargote, V R Gabidullina, A V Zaborovsky, A M Panin, N V Stankova, P Yu Peretyagin","doi":"10.17116/stomat20241030315","DOIUrl":"https://doi.org/10.17116/stomat20241030315","url":null,"abstract":"<p><strong>The aim of the study: </strong>Was to determine the presence of an amoxicillin-based antibiotic in bone implant biopsies by Raman spectroscopy in an experiment.</p><p><strong>Materials and methods: </strong>Experimental animals (<i>n</i>=10, a miniature pig of the Svetlogorsk breed) were divided into 2 groups of 5 animals. Groups 1 and 2 were injected with amoxicillin 2 ml per 20 kg of body weight 30 minutes before dental implantation surgery, then group 2 was additionally injected with 1 ml per 20 kg of body weight for 5 days. Each animal has 6 implants installed. On the 1st, 3rd, 7th, 14th day, an implant-bone biopsy was removed from each animal, micro-preparations were made and Raman spectroscopy was performed to assess the peak matching of the Raman spectrum.</p><p><strong>Results: </strong>In animals of the 1st and 2nd groups, the main peak of the Raman spectrum, which is closest to the values of the antibiotic spectrum of interest to us, is located closer to 1448 cm<sup>-</sup><sup>1</sup> and 1446 cm<sup>-1</sup>, respectively. At the same time, in both observations, the peaks relate to the spectrum of bone tissue, which cannot indicate the content of an antibiotic in the drug.</p><p><strong>Conclusion: </strong>No scattering spectra corresponding to the antibiotic molecule were found in any animal from both groups, regardless of the mode of administration and dosage of amoxicillin. The detected peaks corresponded to bone tissue without an antibiotic.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"103 3","pages":"5-10"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141433013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2024-01-01DOI: 10.17116/stomat202410302191
O O Yanushevich, K A Pashkov, V A Bondar'
{"title":"[From the history of domestic dentistry: Moscow Dental School of the Privat-docent of Moscow University, MD Gilyariy Ivanovich Vilga].","authors":"O O Yanushevich, K A Pashkov, V A Bondar'","doi":"10.17116/stomat202410302191","DOIUrl":"https://doi.org/10.17116/stomat202410302191","url":null,"abstract":"<p><p>Based on archival data, the authors describe the Moscow School of Dentistry with dental courses for doctors, dentists, and dentists of the Moscow University, Privat-docent Dr. Gilyari Ivanovich Vilga, examine the background to its formation, provide unique archival data on the location of the school, as well as its internal organization and equipment. The authors review in detail the program of courses, as well as their duration, cost, and form of student accountability. During its existence (1909-1918), more than two thousand dentists were educated at G.I. Vilg's school, among them Alexander Ivanovich Evdokimov, a future corresponding member of the USSR Academy of Medical Sciences, director of the State Institute of Dentistry (GIZ) and the State Institute of Dentistry and Odontology (GIZO). The authors of the article also focus on analyzing the differences in the approaches to the organization of several dental schools, viz: The First Moscow I.M. Kovarsky School of Dentistry and the Second G.I. Vilga School of Dentistry. In his efforts, I.M. Kovarskij's aspirations to establish the best dental school in Russia were crowned with success: a specially constructed and equipped building meeting the state-of-the-art requirements (the building even boasted an X-ray machine), and the best professors and instructors of the University of Moscow of that time were hired. In contrast, G.I. Vilga rented premises for his school, the equipment was in short supply, and he himself was the only eminent professor. Nevertheless, his fierce desire to unite the entire dental community and organize the best dental care for the entire population of Russia allowed his brainchild to enter the top five schools of the time.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"103 2","pages":"91-95"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140915720","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2024-01-01DOI: 10.17116/stomat202410302141
M I Muzikin, A K Iordanishvili, F F Losev, S G Grigoriev
{"title":"[Reparative potential of bone tissue and associated influencing factors].","authors":"M I Muzikin, A K Iordanishvili, F F Losev, S G Grigoriev","doi":"10.17116/stomat202410302141","DOIUrl":"https://doi.org/10.17116/stomat202410302141","url":null,"abstract":"<p><strong>Objective: </strong>The aim of the sthudy. To study the influence of general and local factors on the regenerative potential of bone tissue to optimize augmentation mechanisms in the treatment of jaw atrophy.</p><p><strong>Materials and methods: </strong>The influence of general and local factors on the regenerative potential of the bone during the augmentation operation of the alveolar process (part) of the jaw in 68 patients was studied. The survival rate of dental implants and the incidence of complications after completion of dental rehabilitation in the long-term follow-up period (more than 5 years) were evaluated. 18 indicators were studied, which were evaluated by qualitative and quantitative methods. The study of the effect of indicators on regeneration was carried out using an accurate Fischer test for conjugacy tables. The assessment of the strength of the influence was calculated as the ratio of the chances of developing an unfavorable outcome of bone grafting and dental implantation.</p><p><strong>Results: </strong>He highest chances of developing adverse outcomes were found in smoking patients with diabetes mellitus, high body mass index, low survival of bone walls, severe bone atrophy (5.6 and higher class according to Cawood & Howell), three-dimensional bone defect, in the absence of 3 or more bone walls, the presence of subcompensated and decompensated psychological state the patient. In the course of histological examination, the influence of these factors on the mechanisms of reparative osteogenesis morphologically manifested a lower degree of progress of regenerative processes and a lower degree of maturity of bone tissue.</p><p><strong>Conclusion: </strong>To reduce the chances of developing an unfavorable outcome, in the presence of negative general and local factors, it is not advisable to use dental implantation simultaneously with bone augmentation procedures. In order to reduce the pathophysiological impact of negative factors during sinus lifting, increase the proportion of autosteal material for potentiating the metabolic activity of bone tissue, as well as prescribe antioxidant, antihypoxant and membrane stabilizing therapy before surgery and in the early postoperative period.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"103 2","pages":"41-49"},"PeriodicalIF":0.0,"publicationDate":"2024-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140915922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310205170
Z S Chayka
{"title":"[Aesthetic management of erosive tooth wear using injection molding technique].","authors":"Z S Chayka","doi":"10.17116/stomat202310205170","DOIUrl":"10.17116/stomat202310205170","url":null,"abstract":"<p><p>In this article, on the example of a clinical case, the technique of restoring two central teeth in a patient with increased enamel erasability with highly filled fluid composite materials using injection techniques is described. The application of this technique has become possible because the new fluid composites have similar mechanical, physical and aesthetic properties to universal composite materials.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 5","pages":"70-74"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71486871","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310205140
T V Brailovskaya, A G Nadtochiy, A K Gadzhikulieva, Z M Abayev
{"title":"[The possibility of obtaining bone autograft from the anterior palate to restore limited bone defects].","authors":"T V Brailovskaya, A G Nadtochiy, A K Gadzhikulieva, Z M Abayev","doi":"10.17116/stomat202310205140","DOIUrl":"10.17116/stomat202310205140","url":null,"abstract":"<p><strong>Objective: </strong>Determination of the optimal zone of the alveolar process of the upper jaw for bone autograft sampling according to cone-beam computed tomography.</p><p><strong>Material and methods: </strong>A study was conducted to assess the possibility of taking a bone autograft from the palatine surface of the alveolar process of the upper jaw. The criteria for inclusion of patients in the study were the presence of a complete dentition and the absence of removed teeth in the upper jaw. A total of 50 patients participated in the study. Determination of the optimal zone for bone autograft sampling was carried out using cone-beam computed tomography (CBCT) of the upper jaw.</p><p><strong>Results: </strong>The optimal area for bone autograft sampling is the area of the palatine surface of the alveolar process in the projection of the frontal group of teeth and the area of the upper jaw mound. When taking bone autograft in he projection of the frontal group of teeth and the area of the upper jaw mound with a probability of 95.11%, a 4 mm long trepan can be used. In 39.6% of cases, the parameters of the alveolar process allow the use of standard trepans with a diameter of 3.5 mm, which makes it possible to obtain a bone cylinder with a diameter of 3 mm. At the same time, in the area of the alveolar process of the frontal group of teeth, it is possible to pick up bone autograft more by 16-23 mm<sup>3</sup> than in the the area of the upper jaw mound.</p><p><strong>Conclusion: </strong>The palatine surface of the alveolar process can be used for bone autograft sampling when planning to eliminate limited defects of the upper jaw. The CBCT method makes it possible to determine the optimal bone autograft sampling zone and the available bone volume, which minimizes injury to the patient.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 5","pages":"40-49"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71486882","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310205120
I N Antonova, L Yu Orekhova, V D Goncharov, R V Yashkardin
{"title":"[The results of the study of the focus of initial caries of human tooth enamel in vitro using atomic force microscopy].","authors":"I N Antonova, L Yu Orekhova, V D Goncharov, R V Yashkardin","doi":"10.17116/stomat202310205120","DOIUrl":"10.17116/stomat202310205120","url":null,"abstract":"<p><strong>Objective: </strong>Identify structural disorders of the surface of the enamel of a human tooth during the development of the carious process in the «white spot» stage using atomic force microscopy (AFM).</p><p><strong>Material and metods: </strong>The studies were carried out on 10 molar samples in areas with initial caries in the white spot stage. 6 areas of initial caries were scanned using the atomic force microscope Cetus Light (Nano Scan Technology, Russia) in semi-contact mode. Criteria were proposed for comparing the results of AFM scanning of tooth enamel surface samples and, based on them, the nature of the main structural disorders of the enamel surface in the affected area was determined.</p><p><strong>Results: </strong>For all the samples studied, the healthy enamel surface was smoother compared to the enamel in the area of the clinically visible «white spot» and in the immediate vicinity of it. The heterogeneity of the enamel surface in the center of the white spot» for all the samples studied was at least 60% higher than at the edge of the process. It was revealed that the heterogeneity of the surface outside the clinically visible white spot at a distance of less than 1 mm from its perimeter is at least 30% higher than that of healthy tissue of the same tooth. It is shown that the heterogeneity of the enamel surface in the center of the caries area in the white spot stage is at least 4 times greater than the heterogeneity of the surface of the healthy enamel of the same tooth, which indicates its demineralization.</p><p><strong>Conclusion: </strong>The established features of the spread of the initial carious process can be used in clinical practice for the diagnosis and dynamic observation of the processes of enamel demineralization.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 5","pages":"20-26"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71486883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310206122
R A Rozov, V N Trezubov, A B Gerasimov, G S Azarin
{"title":"[A prospective single-cohort study of implant-supported full-arch metal-ceramic prosthesis with gold-platinum alloy framework for treatment edentulous mandible in elderly patients: 15-year report].","authors":"R A Rozov, V N Trezubov, A B Gerasimov, G S Azarin","doi":"10.17116/stomat202310206122","DOIUrl":"10.17116/stomat202310206122","url":null,"abstract":"<p><strong>Objective: </strong>To study the effectiveness of implant-supported full-arch metal-ceramic prosthesis with gold-platinum alloy framework in elderly patients.</p><p><strong>Materials and methods: </strong>The study included patients with complete and/or partial loss of teeth and terminal dentition. In 2007-2008, 354 implants were inserted in 27 patients. The age of the patients was 61.31±5.08 years. Mombelli index criteria (mBI [modified Sulcus Bleeding Index]) were used. The plaque index was determined using a modified Löe & Silness method. The state of the peri-implant bone (ΔMBL) was determined by a series of OPG. The Geriatric Oral Health Index (GOHAI) was used to assess oral health in the elderly.</p><p><strong>Results: </strong>Metal-ceramic full-arch implant prostheses with a gold-platinum alloy framework, based on a sufficient and optimal number of implants (6-8), showed high survival rate (100%) after 15 years. Marginal bone loss (ΔMBL) after 15 years was -1.44±1.27 mm. The survival rate of implants was 99.4%. Scores on the GOHAI scale were higher in patients after orthopedic rehabilitation (from 52.7±7.1 to 54.1±8.4, <i>p</i><0.001).</p><p><strong>Conclusion: </strong>After 15 years, all prostheses had mechanical defects, which at the same time allowed them to be used without restrictions. Screw fixation of full-arch implant prostheses, although it was associated with mechanical complications, nevertheless made it possible to perform surgical interventions in a timely manner and stop the development of inflammatory complications. Thus, we do not see any grounds for removing metal-ceramic prostheses and replacing them with new implant prostheses even after a 15-year period of operation. At the same time, it is necessary to take into account the reduction in the possibility of individual oral hygiene in elderly patients, as well as possible restrictions on self-visiting a dentist or dental hygienist.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 6","pages":"22-27"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138300214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310206251
V A Badalyan, A D Posessor, Z M Stepanyan, A I Zakharova, E A Levonian
{"title":"[Measuring methods of volumetric changes of soft tissues at dental implants site and tooth recessions site].","authors":"V A Badalyan, A D Posessor, Z M Stepanyan, A I Zakharova, E A Levonian","doi":"10.17116/stomat202310206251","DOIUrl":"https://doi.org/10.17116/stomat202310206251","url":null,"abstract":"<p><p>The article is a review of literature on various methods for measuring gingival thickness at implant site and tooth recession. The purpose of the study was to analyze existing methods for assessing volumetric changes in soft tissues based on literature data and give recommendations on the choice of methods. The authors analyzed available methods and identified limitations and recommendations for the use of different methods. The literature review is also helpful to identify promising methods for assessing changes in soft tissue volume, which may help authors of future studies with method selection.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 6. Vyp. 2","pages":"51-54"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"138804382","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
StomatologiyaPub Date : 2023-01-01DOI: 10.17116/stomat202310205156
I D Borodina, S V Apresyan, A G Stepanov, D S Butkov, G V Sanosyan
{"title":"[Clinical efficiency of occlusive splints in the treatment of patients with temporomandibular joint dysfunction complicated by bruxism].","authors":"I D Borodina, S V Apresyan, A G Stepanov, D S Butkov, G V Sanosyan","doi":"10.17116/stomat202310205156","DOIUrl":"10.17116/stomat202310205156","url":null,"abstract":"<p><strong>Objective: </strong>Improving the effectiveness of treatment of patients with temporomandibular joint (TMJ) dysfunction complicated by bruxism.</p><p><strong>Material and methods: </strong>70 patients with signs of parafunction of the masticatory muscles were selected for the clinical study. The patients were divided into 2 groups of 35 people. Splints were made for patients from the groups using 2 different 3D printing methods. The treatment was monitored using clinical and instrumental studies, electromyography of the muscles themselves and computed tomography of the TMJ after 3, 6 and 12 months.</p><p><strong>Results: </strong>The severity of hypertonicity of the masticatory muscles decreased by the end of 3 months of treatment with the help of repositioning occlusal splints. After 6 months of treatment, the mean BEA decreased in both study groups, but to a lesser extent than in the first 3 months. After wearing a splint after 12 months, the decrease in muscle tone was insignificant.</p><p><strong>Conclusion: </strong>The clinical use of positioning splints plays a crucial role in the stabilization of occlusion and is a mandatory stage of complex treatment of patients with pathology of the occlusal-musculoskeletal complex.</p>","PeriodicalId":35887,"journal":{"name":"Stomatologiya","volume":"102 5","pages":"56-60"},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71486874","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}