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Most developing countries are disposing of large amounts of biodegradable waste in landfills. Generated landfill gas (LFG) can have negative impact on climate changes but it also can be used as a renewable energy resource. This paper aims to present an application (DeponIS) which supports business processes of waste management on municipal landfills in Serbian conditions. That way better prediction of available LFG quantities can be achieved. This application can help management decisions in several areas: available operational data in real time and strategical decisions based on projections about quantity of LFG in future. It can also be used as a generator for annual reports for Environmental Protection Agency and be in accordance with the polluter pays principle.

Background/Aim. C-shaped canals are a complex morphological variation of the tooth root canal system that, if present, could greatly affect the outcome of endodontic therapy. The prevalence of these canal configurations varies between the populations of different ethnic and geographical origins. Therefore, the goal of this study was to analyze the prevalence and morphology of mandibular second molar C-shaped canals in the population of Central Serbia. Methods. The study included a total of 1 99 mandibular second molars receiving a cone-beam computed tomography (CBCT) examination and determining the presence of C-shaped canal systems, their configuration, minimal wall thickness and its relative position on axial cross-sections at the coronal, middle, and apical level. Results. The prevalence of C-shaped mandibular second molars was 5.53%. C1 canal configuration was the most frequent at the coronal cross-section, while C2 configuration was the most frequent at middle and apical cross-sections. Minimal wall thickness decreased going apically, with the mean value of 1.01 mm at the coronal, 0.87 mm at the middle, and 0 .67 mm at the apical cross-sections. Minimal wall thickness was mostly directed lingually at all cross-sectional levels. Conclusion. C-shaped canals should be expected in mandibular second molars of the population of Central Serbia. CBCT was shown to be the most valuable technique to determine C-shaped canals and facilitate understanding of the C-shaped canal morphology; its implementation could improve the success of endodontic therapy, especially if the complex root canal configuration is present.

This paper describes and evaluates an application which provides the simulation of the functioning of the central processor (CPU). The simulation provides visual representation of anything occurring both at the level of arithmetic logic units (ALU) for different arithmetic and logical operations and at the level of bits. The evaluation of the application of this simulator in teaching was also conducted. The sample included 95 students from the Faculty of Technical Sciences in Čačak, study program - Information Technologies. The method with parallel groups was applied in this research. One group of students mastered the contents of the ALU in traditional way of teaching, while the other group used the simulator. Their advancement in ALU knowledge was measured by knowledge test specially designed for this research. In the end, the students of both groups evaluated the use of the simulator in teaching. The results of the research showed that students who studied with simulators were more motivated and achieved better results than students who learned the same content in a traditional way.

The goal of this paper is to provide a comprehensive overview of application of multi-criteria decision making (MCDM) methods in papers from the field of ecotourism and sustainable tourism. A search has been done of the relevant terms in titles, abstracts and keywords found in papers from 26 prominent journals from the field of tourism belonging in Web of Science (WoS) Clarivate Analytics. It has been established which MCDM methods were used and who are the most common authors of such papers. A keyword frequency analysis was also performed. It is established there are 39 papers in the field of ecotourism and sustainable tourism where MCDM methods were applied whereby all were published after the year 2000, as well as that their number is constantly increasing.

Background/Aim. For successful endodontic therapy, it is necessary to know root morphology. Therefore, the aim of our study was to analyze root canal morphology and root canal length of permanent molars in a Serbian population, using cone-beam computed tomography (CBCT). Methods. The study included a total of 305 maxillary molars, and 280 mandibular molars receiving cone-beam computed tomography examination and determined root numbers, canal morphology according to Vertucci classification, and canal lengths. Results were correlated with sex and tooth location in the jaw. Results. The mesiobuccal roots of first maxillary molars showed Vertucci type I in 45.7%, followed by type II in 29% of cases. For the second molar, Vertucci type I was found in 60.5% of cases in mesiobuccal canals. Palatal and distobuccal canals mostly presented Vertucci type I configuration. The mesial roots of mandibular molars had the highest frequency of two canals with Vertucci type IV as the most frequent for the first molar, and Vertucci type II for the second molar. Distal roots most commonly had one canal in both molars. Palatal canal length was the highest in maxillary first molars, with the mean value of 20.62 mm, while in second molars, the highest length value was for the mesiobuccal canal (20.09 mm). In both mandibular molars the mesial root canal was the longest one. Differences were found according to sex and tooth location in the jaw. Conclusion. Mesiobuccal roots of maxillary first molars had two canals; it was more frequently compared to second molars. Mesial roots of mandibular molars showed same frequency of two canals, and diversity in Vertucci types. Male patients tended to have higher complexity of root canal morphology compared to that of females. CBCT can improve understanding of the root canal morphology.

Introduction. The anatomy and morphology of the roots and root canal systems of multi-rooted teeth, especially the molars, shows numerous variations. Preoperative radiography, in particular cone-beam computed tomography (CBCT), has exceptional significance in detecting anatomical variations and unusual root canal morphologies, which are extremely important to be familiar with in order to undertake successful endodontic therapy and minimize procedural errors. Outline of cases. This report presents cases of incidental diagnosis of an unusual root anatomy and root canal morphology of permanent molars in two patients. Diagnosis in the first case was made using orthopantomography and confirmed after extraction therapy. The second case reviled unusual root anatomy and root canal morphology of the permanent molar after preoperative CBCT imaging. Conclusion. Anatomical and morphological variations of roots and root canal systems can occur in any tooth. Clinicians should expect these variations, which should be thoroughly investigated when considering dental treatment.

Foreign direct investments include equity capital, reinvested earnings and debt relations between ownership-related residents and non-residents. Since 31 October 2014, the Croatian National Bank has started to publish information in the field of statistics Relations (balance of payments, foreign debt and the IIP) in accordance with the methodology prescribed by the sixth edition of the Manual on Balance of Payments (Eng. Balance of Payments and International Investment Position Manual, BPM6), thus changing the presentational form of direct investment. Direct investments are not classified according to the so-called direction of investments (Eng. directional principle) on direct investment in Croatia and direct investment abroad anymore, but according to BPM6 apply the socalled principle of assets and liabilities (Eng. Assets / Liabilities principle). The aim is to point out the differences between the standards BPM5 and BPM6 and determine which activities and which countries are the most represented in the structure of direct investments in Croatia. By identifying relevant activities and countries in the structure of foreign direct investment, relevant information is obtained about the macroeconomic state of the Republic of Croatia and about the opportunities and potential dangers that certain activities and countries provide.

Background/Aim. Intervertebral disc degeneration (IDD) occurs as consequence of combined effects of genetic, agerelated, environmental and occupational factors. Lumbar disc herniation (LDH) develops mostly due to IDD. The aim of this study was to investigate whether the frequency of LDH is higher at the level of the most pronounced IDD, and whether a category of physical workload influences higher IDD on level L3-L4, L4-L5 and L5-S1 separately. Methods. The research included 60 patients with permanent employment, hospitalized due to LDH. A grade of IDD was assessed by lumbosacral preoperative magnetic resonance imaging (MRI), according to Pfirmann's MRI classification system. Occupational factors were determined by a specific questionnaire. Results. Out of the 60 patients participating in the study, 33.3% had jobs with easy workload, 23% had moderate workload, while 43% had heavy workload. Herniated discs were found at level L3-L4 in 8.3%, at level L4-L5 in 46.7% and at level L5-S1 in 45% patients. The symptomatic discs at level L5-S1 showed statistically significant frequency of degenerative changes of grades IV and V. Binary logistic regression results showed that the strongest predictor of IDD grade for examined levels was physical workload. Positive association of physical workload and IDD grade was observed in all cases. Higher grades of IDD are more likely for patients with both higher TE and heavier physical workload (OR 2.011) at level L3-L4. At levels L4-L5 and L5-S1 higher degree of IDD was more likely for females with heavier physical workload (OR 1.978 and 2.433 respectively). Conclusion. Symptomatic discs show higher frequency of higher grades of IDD but herniation does not occur solely at the disc of the most prominent degenerative changes. The results suggest importance of inter- influence of physical workload and the years of employment and the inter-influence of physical workload and gender, on degeneration of lumbar discs.

This paper deals with comparative analysis of two different types of objective techniques for criteria weighing: Entropy and CRITIC and two MCDM methods: MOORA and SAW on example of an air conditioner selection. We used six variants for calculation of normalized performance ratings. Results showed that the decision of the best air conditioner was basically independent of the MCDM method used, despite the applied technique for determination of criteria weights. Complete ranking within all of the combinations of methods and techniques with diverse ratio calculation variants showed that the best ranked air conditioner was A7, while the worst ones were A5 and A9. Significant positive correlation was obtained for almost all the pairs of variants in all the combinations except for the MOORA - CRITIC combination with SAW - Entropy combination to have the highest correlations between variants (p < 0.01).

Recent advances in regenerative medicine provide encouraging strategies to produce artificial skin substitutes. Gelatin scaffolds are successfully used as wound-dressing materials due to their superior properties, such as biocompatibility and the ability to mimic the extracellular matrix of the surrounding environment. In this study, five gelatin combination solutions were prepared and successfully electrospun using an electrospinning technique. After careful screening, the optimal concentration of the most promising combination was selected for further investigation. The obtained scaffolds were crosslinked with 25% glutaraldehyde vapor and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. The incorporation of antibiotic agents such as ciprofloxacin hydrochloride and gentamicin sulfate into gelatin membranes improved the already existing antibacterial properties of antibiotic-free gelatin scaffolds against Pseudomonas aeruginosa and Staphylococcus aureus . Also, the outcomes from the in vivo model study revealed that skin regeneration was significantly accelerated with gelatin/ciprofloxacin scaffold treatment. Moreover, the gelatin nanofibers were found to strongly promote the neoangiogenic process in the in vivo chick embryo chorioallantoic membrane assay. Finally, the combination of gelatin's extracellular matrix and antibacterial agents in the scaffold suggests its potential for effective wound-healing treatments, emphasizing the importance of gelatin scaffolds in tissue engineering.

This prospective clinical study aimed to assess self-reported orofacial esthetics, chewing function, and oral health-related quality of life (OHRQoL) over three years in the Kennedy Class I patients without posterior dentition who received free-end saddle removable partial dentures (RPDs) retained by two mini dental implants (MDIs) inserted in the canine/first premolar region. The study's robust findings reaffirm the viability of MDI-retained RPDs as a treatment modality in contemporary prosthodontics, instilling confidence in the dental community., Materials and Methods: 92 participants with posterior edentulism in the maxilla or mandible received 184 MDIs and 92 RPDs. After one year, three participants were excluded, and another seven were excluded after three years. The final sample was 82 participants. Self-perceived orofacial esthetics was assessed by the Orofacial Esthetic Scale (OES), chewing function by the Chewing Function Questionnaire (CFQ), and the OHRQoL by the OHIP-14. Statistical analysis utilized multivariate regression analysis, standardized effect size calculation, Wilcoxon Signed Rank test, and Friedman's test., Results: OHRQoL and chewing function significantly improved (p < 0.001) one month after MDI loading by the new RPDs and continued to improve over the observation period (p < 0.05). The OES also significantly improved (p < 0.001) and remained almost unchanged over the next three years (p = 0.440)., Conclusion: Despite the limitations of this study, the MDI-retained RPD appears to be a viable treatment modality in contemporary prosthodontics from the patients' perspective., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl 3 ) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.

Headaches are one of the most common ailments in modern society, leading to severe diminishing of general activities and they result in significant impact on the patient's quality of life. Blink reflex is an objective neurophysiological method for determining the status of the trigeminal system, facial nerve and the lateral part of medulla oblongata. The aim of this study was to examine the connection between trigeminal nerve dysfunction and various types of headaches using functional electrophysiological assessment of blink reflex tests in patients and controls. The sample comprised 60 subjects with headache attacks, 44 females, and 16 males). The control group consisted of 30 healthy subjects (19 females, and 11 males) who did not suffer from headaches. The age of subjects ranged from 20 years to 76 years with the mean of 42.81 years. Trigeminal nerve function was assessed by using blink reflex tests in patients suffering from headaches and in controls, applying the standard procedure described by Kimura et al. Pathological findings of blink reflex were observed in 58.3 % of patients suffering from headaches and in only 20 % of cases in the control group. The application of Yates’ χ2 test showed a significant correlation between pathological blink reflex and headache occurrence (χ2 = 10.354; P = 0.001). Normal blink reflex was found in 41.7 % of patients suffering from headaches and in 80 % of control group subjects. Females with pathological blink reflex have 4 times higher risk for headaches than controls (OR = 4.107; 95% CI = 1.036 - 17.565). Males with pathological blink reflex have a considerably higher risk for headaches, and it was 13 times higher than in controls (OR = 13.500; 95% CI = 1.555 - 153.646). There is a strong correlation between pathological blink reflex and the occurrence of headaches in both genders, indicating significant association of trigeminal nerve dysfunction with the occurrence of headaches. The use of blink reflex testing could be of help to detect patients with an increased risk for headaches.

Lumbar disc herniation (LDH) is the most common disease among working population requiring surgical intervention. This study aims to predict the return to work after operative treatment of LDH based on the observational study including 153 patients. The classification problem was approached using decision trees (DT), support vector machines (SVM) and multilayer perception (MLP) combined with RELIEF algorithm for feature selection. MLP provided best recall of 0.86 for the class of patients not returning to work, which combined with the selected features enables early identification and personalized targeted interventions towards subjects at risk of prolonged disability. The predictive modeling indicated at the most decisive risk factors in prolongation of work absence: psychosocial factors, mobility of the spine and structural changes of facet joints and professional factors including standing, sitting and microclimate.

The aim of the study was to develop and to test the psychometric properties of the Slovenian version (OHIP-SVN) in the new cultural context. Construct validity was tested on 430 subjects, test-retest reliability on 60 subjects, internal consistency on 460 subjects, and responsiveness on 30 patients with a treatment demand (toothache). The significant association between the OHIP summary scores and the self-reported oral health (p < 0.001) confirmed the construct validity. The test-retest reliability showed high intraclass correlation coefficients and no significant differences between the two administrations (p > 0.05). The internal consistency showed high Cronbach's alpha (0.97). The responsiveness was confirmed by the statistically significant difference between the mean OHIP score at baseline and follow-up (p < 0.001) and by a considerable effect size in the patients with a treatment demand (0.515). The OHIP-SVN, as one of the first translation into one of the Slavic family of the languages proves that this instrument is suitable for the assessment of the Oral Health Related Quality of Life in Slovenia.

Purpose of this study was to develop a Croatian version of the Oral Health Impact Profile questionnaire (OHIP--CRO49), following the accepted cross-cultural adaptation technique guidelines. The original version was translated by using a forward-backward translation method. The psychometric properties of the OHIP-CRO49 were tested. To test the construct validity 163 randomly selected subjects and 26 prosthodontic patients participated. The construct validity was supported by the association between the OHIP-CRO49 sum-scores and the self-reported oral health and five oral disorders. The test-retest reliability was tested on 30 prosthodontic patients and 30 students, and it was supported by high intraclass correlation coefficients (r = 0.63 to 0.95). To test the internal consistency 163 randomly selected subjects (general population), 26 prosthodontic patients and 29 dental students participated, and it was supported by high Cronbach's alpha coefficients (0.60 to 0.97). The resposiveness was tested on 21 patients with a treatment demand (toothache), and was supported by a statistically significant mean OHIP-CRO49 score difference (from 108.48 to 27.57) and a high effect size (2.96 and 3.48). Adequate psychometric properties in a typical patients' population make the new instrument suitable for assessment of Oral health-related quality of life (OHRQoL) in Croatia.

Digital photography has become available to everybody. The aim of this study was to examine possibility of calculating the width of a missing central incisor using digital photographs. Digital photographs were obtained from 51 dentate subjects using a 3.1 Megapixel digital camera from various distances: 35 cm, 70 cm, 1 m and 1.5 m. For the calculation of the width of maxillary left central incisor (MLI), the following equation was used: MLI(calculated) = Photographic width of MLI x IPD / photographic IPD. Statistical analysis was made (Kolmogorov-Smirnov test, dependent sample t-test, correlation and frequencies) using SPSS 10.0 for Windows. Results revealed no significant difference between the calculated MLI (70 cm, 1 m and 1.5 m distance) and actual MLI, however calculated MLI from 35 cm distance was significantly different from the actual MLI value (p < 0.01). The highest correlation was between calculated MLI (70 cm distance) and actual MLI. However, the highest percentage of results from a distance of 70 cm also fitted within +/- 0.3 mm; +/- 0.5 mm and +/- 1 mm difference from the actual MLI values. However, the results obtained from 1 m distance were also satisfactory. The technique of use of digital photography is of proven value in calculating the width of a maxillary central incisor. The photographs using a simple digital camera should be taken from a distance from 70 cm to 1 m. Saving such photographs in a dental office may eventually be helpful for calculating dimensions of artificial teeth.

Background: Except for denture quality, many other factors are related to a patient's satisfaction with complete dentures (CDs)., Methods: A total of 222 patients with CDs took a part in this study. A questionnaire divided into 3 parts was completed by both the patients and the dentist, independently. The patients rated their dentures using a scale ranging from 1 to 5 (1 = dissatisfaction to 5 = excellent), and a dentist rated the quality of the denture and the denture-bearing area., Results: Patients were mostly satisfied with the quality of their CDs. Only 7.2% of the patients were absolutely not satisfied with their dentures. Patients with a low level of education were more satisfied in general with their aesthetic appearance. Patients with better self-perception of their affective status and quality of life showed higher levels of general satisfaction. Patients with better self-perception of their economic status showed lower levels of satisfaction. Younger patients wearing dentures for the first time, with short periods of being edentulous, and with better quality maxillary denture-bearing areas were more satisfied with the retention of maxillary CDs. In contrast, younger patients with first-time dentures, a short period of being edentulous, and with better quality mandibular denture-bearing areas gave lower ratings to the retention and comfort of wearing mandibular dentures., Conclusions: Level of education, self-perception of affective and economic status, and quality of life are all related to patient satisfaction. However, the quality of dentures shows the strongest correlation with patient satisfaction. Not only the quality of the denture-bearing area but the denture-wearing experience itself seems to be more important in determining patient satisfaction with mandibular CDs.

Alveolar bone loss (RRR) is a continuous process following tooth extraction, more pronounced during the first few months after the tooth extraction than later. The RRR in the mandible is twice that of the maxilla during a 1-year period and the mandibular: maxillary resorption ratio increases further to 4:1. So far, the etiology of RRR has not been elucidated. It has been speculated that both systemic and local factors contribute. The aim of this study was to analyse the rate of RRR in five different regions of both jaws on lateral cephalograms of 100 complete denture wearers during a one-year period and to compare the rate of RRR between patients being edentulous over a different period of time and between patients with different body mass index. The height of residual ridges was measured on 5 different sites at the delivery of the dentures and a year later using a calibrated grid. The results revealed significant RRR in a one year period. Body mass index had no significant influence on the rate of RRR on any of the five examined sites of the maxilla or the mandible (p > 0.05), while the period of edentulousness had a significantly higher rate of resorption in first 3 sites of measurement (anteriorly) in patients being edentulous less than 1 year than in patients being edentulous for 1-10 years or for over 10 years (ANOVA, p < 0.05).

The purpose of this study was to examine how Co-Cr-Mo dental alloy behaves in the solutions of different pH value and different composition over a relatively long period of time. Co-Cr-Mo dental alloy was exposed in vitro to either simulated saliva (phosphate buffer pH 6.0), a highly acidic medium resembling the extreme conditions in the oral cavity (phosphate buffer pH 3.5), and in lactic acid at pH which occurs under the dental plaque (lactic acid pH 3.5). The alloy samples were immersed in these three solution for 1, 2, 3, 4, 5, 6, 7, 14, 21, and 30 days. Solutions were analysed with the ICP-AES. The analysis showed that during one month cobalt (Co), chromium (Cr), iron (Fe), zinc (Zn) and nickel (Ni) ions had been released from tested samples in all three solutions. The results of this study indicate that the leaching of the Co, Cr, Fe, Zn and Ni ions in the solution was dependent both upon the nature of the solution in which the alloy was immersed and the duration of the immersion (p < 0.001).

Objective of this study was to determine the accuracy of the method of the clinical intraoral densitometry, to compare differences in the calculation with or without subtraction of the background adjacent soft-tissues from the stepwedge (SW) and to verify which regression model best fitted the experimental data in order to express the measured values in equivalents of SW thickness. Two intraoral radiographs, one after another, were made for each of 6 patients. A copper SW (6 steps, thickness 0.05-0.3 mm) was attached to each radiograph, trying to avoid the superimposition of the bony structures. Films were processed and digitized. Grey levels were measured on each step of the SW, on the background of the SW and on the same 3 randomly chosen regions of interest (ROIs) on each digitized image. The measurement with and without the subtraction of optical densities of the background around the SW from the optical densities of the SW was performed. For the calculation of the SW thickness equivalents, the regression analysis was performed by using different regression models. The best fitting regression model was the 3rd degree polynomial. The results were more precise when using the subtraction of the background overlapping the SW.