TYPES OF PIT AND FISSURE SEALANTS. INDICATIONS AND CONTRAINDICATIONS FOR SILANIZATION. REVIEW

Background: Dental sealants have been used to reduce the incidence and severity of dental caries in the pits and fissures of teeth for over 40 years. Since that time, numerous scientific discoveries have led to the development of multiple generations of new sealant materials. Aim: The aim of this paper is to summarize the findings of reviews regarding the types of pit and fissure sealants, indications and contraindications for their use. Methods and materials: Previous systematic reviews on this topic were used as the basis for the current review. Cochrane, MEDLINE, Embase, and a few other bibliographic databases were searched for English and Bulgarian-language articles. The year of publication of the searched articles was limited from 2000 to 2020. Only articles in English and Bulgarian languages were read in full. Results: A total of 114 articles were identified by the literature search, the title and abstract of the articles were examined. Twenty-four original research studies met the inclusion criteria. They were read in full, and evidence was extracted for types of pit and fissure sealants, as well as indications and contraindications for their use. Conclusion: Evidence derived from the literature led to the conclusion that sealants are effective in preventing pit and fissure occlusal carious. The selection of the material used for silanization is made depending on a few factors that should be considered, such as patient's and tooth age, child's behavior and ability to isolate the surfaces which are going to be sealed. Regular examinations are required to be able to determine the need for reapplication of sealants and to maximize the effectiveness and results of the treatment.

ANALYSIS AND EVALUATION OF ADVANTAGES FROM LAPAROSCOPIC APPENDECTOMY

Purpose: The aim of the study is to evaluate the advantages of laparoscopic appendectomy fromour clinical experience in UMHATEM "Pirogov" which resulted in reduced postoperative complications, pain, length of hospital stay, and early return to work. Material and Methods: Data from a study of a patient group in the Department of General, Visceral and Emergency Surgery of UMBALSM "H. I. Pirogov "for the six-month period (01.01.2019 до 01.07.2019) were collected.Eighty-one patients with acute appendicitis who underwent laparoscopic appendectomy were selected. Indicators characterizing basic clinical and pathological features (epidemiology, demography, degree of pathological impairment), surgical approach and its outcomes (postoperative complications, postoperative duration), influence of concomitant factors were studied. Results: The study included 81 patients. The majority of patients were women - 46 (56.79%), men- 35 (43.21%). The mean age of male patients was 31.4 years and for female-28.6 years respectively. Hospitalization times are usually short - most patients are given up to 72 hours (70- 86.42%). Only eleven patients (13.58%) had an extended hospital stay for observation and additional therapy. Conclusion: Laparoscopic appendectomy was verified as an optimal and safe surgical procedure. Laparoscopic approach reduces post-operative pain, shortens hospital stay, reduces complications, and thereby reducing treatment costs.

STUDY OF SERUM OSTEOPROTEGERIN AND RECEPTOR ACTIVATOR OF NUCLEAR FACTOR KAPPA-Β LIGAND IN PATIENTS WITH RHEUMATIC DISEASES

Although rheumatological diseases are widespread, they still have an unclear etiology, pathogenesis, and therapy. Researchers are looking for biomarkers associated with inflammatory and degenerative joint diseases. Serum Osteoprotegerin (s-OPG) and serum Receptor Activator of Nuclear Factor Kappa-Β Ligand (s-RANKL) have not been studied in patients with Diffuse idiopathic skeletal hyperostosis (DISH), spondylosis, ankylosing spondylitis, and gout. The aim of this study was to investigate s-OPG and s-RANKL in patients with various rheumatic diseases. Materials and methods: We studied 135 patients with rheumatic diseases, of which 55 were diagnosed with DISH, 50 with spondylosis, 23 with ankylosing spondylitis, 7 with gout, and 25 were a control group. s-OPG and s-RANKL, serum calcium, ionized calcium, serum phosphorus, alkaline phosphatase, uric acid, urea, creatine, and serum osteocalcin were tested using the ELISA method in the Clinical Laboratory of "St. George" University Hospital, Plovdiv. The results were processed using the statistical program SPSS ver 26, with significance p<0.05. Results: Patients with DISH and ankylosing spondylitis had higher levels of s-OPG, s-RANKL, and s-OPG/s-RANKL ratio than the control group (p<0.05). The s-OPG/s-RANKL ratio in patients with spondylosis and gout was lower than in patients with DISH and ankylosing spondylitis (p<0.05). There are strong correlations between s-OPG, s-RANKL, and the biochemical parameters related to bone metabolism (serum calcium, ionized calcium, serum phosphorus, alkaline phosphatase, uric acid, urea, creatine, and serum osteocalcin)(p <0.05). Conclusion: Our studies show that changes in bone metabolism are similar in patients with DISH and ankylosing spondylitis. Further research is needed to look for a common pathogenetic pathway linking degenerative and inflammatory rheumatic diseases of the axial skeleton.

INVESTIGATION OF LIGHT INTENSITY OF LIGHT CURING UNITS AFTER DIFFERENT PERIODS OF USE

Quartz-tungsten halogen light curing units (LCUs) have been the main source of light for the polymerization of resin based composites (RBCs) for several decades. Since the beginning of the 20th century, however, their use has been reduced due to the invention and improvement of LED LCUs. Various factors can cause a decrease in the light intensity of LED LCUs, one of which is diode aging. The aim of the present paper is to study the change in light intensity of LCUs after different periods of intensive use. For this purpose, the light intensity of 94 regularly used LED LCUs aged between 1 and 10 years was measured with a digital radiometer. The devices were used in conventional mode with maximum light intensity. It was found that regardless of the type and model of LCU, there is a direct relationship between the time of use and light intensity - the longer the operation period of a device is and the more used it is, the lower its intensity is. The decrease in light intensity as devices age is different for different models, as well as for different devices of the same model. In the studied LCUs with a 10-year period of use, 77.5% have light intensity lower than the required minimum of 400 mW/cm2, which makes them unusable. It can be concluded that dentists should regularly monitor and measure the light intensity of their LCUs, especially as they age, to ensure the longevity of their restorative procedures.

COMPARATIVE INVESTIGATION OF KNOWLEDGE OF WILD EDIBLE MUSHROOMS IN VARNA REGION WITH OTHER FOREIGN GEOGRAPHIC ZONES

Purpose: The interest in evaluation of real knowledge of wild edible mushrooms at individual and population level increases mainly in developing countries. The purpose of our inquiry study was to assess the level of knowledge and awareness of the wild mushrooms in a random sample from the population of Varna region in Bulgaria. Material/Methods: We performed an anonymous questionnaire investigation of 200 adult individuals, 100 males and 100 females, from Varna region, including 17 potential opinions from their personal knowledge of wild edible mushroom usage. Statistical data processing was performed using descriptive methods, variation and correlation analyses. Results: Most respondents acquired their knowledge of wild edible mushrooms from their relatives. From all 200 persons investigated 78 respondents were not capable of recognizing at least one wild edible mushroom at all. More respondents trusted other people, who have very good experience with preparation of wild mushrooms, thus relying on differentiation of a mushroom poison. Their awareness was associated with their capacity to properly recognize wild mushrooms as well as their long-term practice to recognize toxic mushrooms. Just a minority of respondents shared that wild mushrooms in their vicinity could be a problem and had a slight idea of mycotherapy. Only two females had heard about training for wild mushroom recognition. There were statistically significant correlation dependences between respondent’s awareness of wild edible mushrooms, on one hand, and individual sex status, educational level and main residence, on the other hand. Conclusion: Our study identified two most recognized wild edible mushroom species in Varna region, edible boletus (Boletus edulis Bull) and parasol mushroom (Macrolepiota procera S. F. Gray). Most respondents acquired their knowledge of wild edible mushrooms from relatives. A problem-oriented training of the population on this topic should be performed to improve awareness of common mushroom features and avoid mushroom poisoning.

ANALYSIS OF USAGE AND QUALITY OF WILD EDIBLE MUSHROOMS BY PEOPLE FROM BULGARIA, COMPARED TO OTHER FOREIGN COUNTRIES

Purpose: Wild edible mushrooms are collected and consumed for centuries worldwide and in Bulgaria as well. This questionnaire investigation aimed at assessing some common mushroom usage practices in a random sample from the population in Varna region, Bulgaria. Material/Methods: We performed a study of 200 adult individuals, 100 males and 100 females, from Varna region using anonymous questionnaire with 12 basic items about wild edible mushroom usage. Statistical data processing was performed using descriptive methods and correlation analysis. Results: There was a prevalence of male and female individuals with secondary and higher education. Most respondents preferred wild edible mushroom gathering in contrast to purchasing. The positive attitude towards wild edible mushroom usage as food is more common in males than in females. Most respondents consumed wild edible mushroom several times during any year. There were statistically significant correlations between urban main residence, on one hand, and wild edible mushroom non-nutritional usage, cooking, drying, preservation and freezing, on the other hand; between secondary educational level, on one hand, and positive attitude towards nutritional usage of wild edible mushrooms, wild edible mushroom cooking, preservation, freezing and drying and applications as therapeutic means; as well as between individual female sex belonging and wild edible mushroom applications as therapeutic means, on the other hand. Conclusion: This questionnaire investigation revealed several interesting peculiarities of the attitudes towards wild edible mushrooms among the population of Varna region and the extent of usage of common mushrooms depending on sex, educational level and main residence of respondents.

EFFECT OF OLIGOSACCHARIDES ON ENZYMES OF CARBOHYDRATE METABOLISM AND ANTIOXIDANT PROTECTION IN IN VITRO TREATED ERYTHROCYTES UNDER CONDITIONS OF HYPERGLYCEMIA

Introduction: The purpose of this experiment is to examine the effect of different oligosaccharides with proven prebiotic effects on enzymes of carbohydrate metabolism and the antioxidant protection of erythrocytes in vitro under conditions of hyperglycemia. Materials and methods: This experiment included 10 healthy men (27±3 years of age). The isolated erythrocytes were treated with 1% and 5% solutions of the following oligosaccharides: lactulose, inulin, galactooligosaccharide and fructooligosaccharide in the presence of 5mM, 50mM and 100mM glucose. After incubation, for 2 hours at 37 °C, the erythrocytes were lysed, and the supernatant was used for analyses of lactate dehydrogenase, hexokinase and glutathione reductase. FRAP (Ferric reducing antioxidant power) method was used for determining the total antioxidant activity of erythrocytes. Results: Lactate dehydrogenase was decreased in the presence of 5% lactulose in groups with 50mM and 100 mM Glc. An increase in the activity of glutathione reductase under severe hyperglycemia (100mM glucose) was observed after treatment with: 1% lactulose, 1% inulin, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides (p<0.005). A significant difference in the enzymatic activity of hexokinase was found in all groups (p<0.05) and of glutathione reductase only in the control group as well as in the groups treated with 1% lactulose, 1% galactooligosaccharide, 1% and 5% fructooligosaccharides Conclusions: Galactooligosaccharides 1% and fructooligosaccharides 1% and 5% cause a statistically significant increase of the enzymatic activities of hexokinase and glutathione reductase in in vitro hyperglycemia induced by 100 mM glucose, as well as an increase in FRAP.

RECURRENCE OF ANEURYSMAL BONE CYST OF THE MANDIBLE: A CASE REPORT

Аneurysmal bone cysts are benign osteolytic lesions with rapid growth, thin walls containing numerous blood-filled cavities. They occur mainly in the pediatric population but are rarely diagnosed in the facial skeleton. Although benign, the condition can be locally aggressive and cause significant weakening of the affected bone structure. This case report presents a 14-year-old boy with Burkitt's tumor (Non-Hodgkin's lymphoma), previously diagnosed with an aneurysmal bone cyst a year ago. He was admitted for treatment at the Clinic of Maxillo-Facial Surgery of the University Hospital "St. George" Plovdiv due to pain and swelling in the left molar area of the mandibula, dating from 2 days. A recurrence of an aneurysmal bone cyst measuring 55/25 mm, which does not require resection of the mandible, was found. After a decision for surgical removal of the formation, under general anesthesia, and preparation of a three-cornered mucoperiosteal flap, the mandibular bone, which is lysed and thinned by the formation, was trepanned. The roots of the affected teeth were resected, and the formation was extirpated. A gauze drain was placed in the formed cavity, and the wound was sutured. Drug therapy included Cefotaxime 2x1.0 - 10 days, starting 3 days before surgery, and Paracetamol 2x1 – 3 days, 2 days before and 1 day after surgery. Prophylactic examinations were scheduled on day 3, 7, 10, 15 after the operation, as well as 3, 6, and 12 months post-op, due to the recurrent nature of the formation.

CHROMOSOMAL POLYMORPHISM IN BULGARIAN PATIENTS WITH REPRODUCTIVE PROBLEMS – ONE GENETIC CENTRE EXPERIENCE

Chromosomal polymorphism is described as normal variants at chromosomal regions with no impact on the phenotype but a possible correlation to infertility and recurrent spontaneous abortions. The aim of this study was to evaluate the effect of the chromosomal polymorphisms involved in families with reproductive failures in the Bulgarian population. Material and methods: A total of 1733 patients with unexplained reproductive failures who visited the Laboratory of Medical Genetics – Varna, Bulgaria, (2004 - 2019) were investigated by conventional cytogenetic analysis GTG and CBG differential banding techniques and analyzed at the resolution 400-550 GTG bands. Results: Chromosomal polymorphisms were found in 173 infertile patients (9,98%). The sex distribution was 6,52% males and 3,46% females. The most frequent finding was inv(9)(qh) (23,7%). The other chromosomal variants, which were found, consisted: 9qh+/- variants (15,1%); polymorphisms on the short arms of the acrocentric chromosomes (21,4%); 16qh+ (12,7%) and 1qh+ (6,9%). Y chromosome polymorphism was found in 27,4% of the males with polymorphisms. Two rare cases of polymorphism involving the centromere regions - 19qcenh+ and 20pcenh+ were also found. Conclusion: There is growing evidence that polymorphisms may have a clinical impact on fertility and could take part in the etiology of RF. In this study, we found a significantly high percentage of polymorphisms (9,98%) among the tested patients, and they were more common among males. The statistical significance of increased incidence of chromosome variations found in our study emphasizes the need for routine evaluation of their role in families with RF in our country.

A PILOT STUDY OF SENSITIZATION TO PLANE TREE POLLEN IN SOFIA, BULGARIA

Purpose: Platanus pollen is a serious cause of asthma, allergic rhinitis and conjunctivitis in many European countries. The aim of the present pilot study is to investigate the sensitization to 3 different plane tree species in a group of patients with pollinosis. Materials and methods: 21 patients were surveyed - 11 men and 10 women. A skin prick test was performed with a set of allergens: Grass pollen mix; Betulaceae pollen mix; Platanusorientalis; Platanusacerifolia; Platanusoccidentalis. Results: 95% of patients are sensitized to grass pollen, with moderate positive skin reactions predominating. 86% have a co-sensitization to tree pollens also, particularly to the birch tree family. Only 3 (14%) of the studied patients showed slight positive skin tests to the studied plane tree allergens, with no significant difference in sensitization to studied Platanus species (p>0,05). Conclusion: At present, the sensitization to different Platanus species is not comparable to that of grass or birch pollen. However, it will be necessary to conduct new long-term, large-scale studies to prove whether Platanus pose a real threat to people in urban areas. The results of this interdisciplinary study are important both for clinical allergologists and for landscape architects and ecologists involved in the planning and management of urban green infrastructure.