This study investigated the distribution and magnitude of stress generated in the enamel of an upper first premolar, after applying normal and excessive occlusal loads in a vertical and horizontal direction, using Finite Element Analysis (FEA). Methodology: A 3D virtual model of an upper first premolar was analyzed. The CT images of the tooth were converted into 3D data using the program MIMICS and Finite Element Analysis (FEA) was used for the stress study. To better understand the distribution of stress generated by occlusal loading, the situation of the enamel in various 3D virtual models was presented. 14 scenarios for the occlusal loading of the virtual models of the upper first premolar were obtained and the areas with the highest concentration of stress were emphasized. Results: In the model with the tooth intact, stress values were higher than the admissible ones in the simulation of the excessive vertical loading, normal horizontal loading and excessive horizontal loading. Stress was found in the buccal cusp area and in the cervical area, mainly on the buccal side of the tooth. In the models with horizontal occlusal tooth wear, stress values were higher than the admissible ones in the simulation of the excessive vertical loading. Stress was found in the cervical area. In the models with oblique occlusal tooth wear, stress values were higher than the admissible ones in the simulation of the normal and excessive horizontal loading. Stress was found mainly in cervical area, on the buccal side of the tooth. Conclusions: The most harmful loads were the heavy vertical ones and the horizontal ones, no matter the magnitude.
Oral health-related behaviors and living conditions play an important role in general and oral health. This study aimed to evaluate caries prevalence and severity in schoolchildren residing in rural and urban areas of Romania, and to correlate these with oral health-related behaviors. An estimation of the required sample size was conducted (sampling error of ±3% at a 95% confidence level), followed by the stratification of administrative units and then the selection of 49 schools. The Hurdle approach was used to analyze the dataset, requiring two sets of analyses for each outcome variable: a multilevel binary model to predict prevalence, and a multilevel Poisson analysis using only non-zero values. The mean and standard deviation (SD) for the dentinal caries index was 4.96 (5.33). Girls were more likely to have non-zero restoration codes (β = 0.14, SE = 0.08, p < 0.05). Low education levels of each parent were associated with an increased likelihood of having non-zero carious tooth surfaces (β = 0.23, SE = 0.06, p = 0.01; β = 0.22, SE = 0.06, p < 0.01). The presence of cavities was predicted by the consumption of carbonated soft drinks (β = 0.19, SE = 0.07, p < 0.01), candies (β = 0.13, SE = 0.06, p < 0.01), sweetened milk (β = 0.12, SE = 0.06, p < 0.05), tea (β = 0.16, SE =0.08, p < 0.05), or cocoa (β = 0.13, SE = 0.06, p < 0.05). Furthermore, the non-zero values of the dentinal caries index were more likely in rural schools (β =−0.37, SE = 0.11, p < 0.01), and a negative association between the county development index and the fillings/restorations index (β = −0.01, SE = 0.01, p < 0.05) was also established. The outcome of this research highlights that the presence of caries (dentinal caries index) in Romanian schoolchildren is influenced by their socioeconomic background, as well as their specific consumption behaviors.
This is an open-access article distributed under the terms of a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International Public License, which permits unrestricted use, adaptation, distribution and reproduction in any medium, non-commercially, provided the new creations are licensed under identical terms as the original work and the original work is properly cited. ORIGINAL PAPER Periodontal clinico-morphological changes in patients wearing old nickel-chromium and copper alloys bridges LUMINIŢA DĂGUCI 1) , CONSTANTIN DĂGUCI 2) , CRISTIANA IULIA DUMITRESCU 3) , CĂTĂLINA FARCAŞIU 4) , DANIELA IOANA TĂRLUNGEANU 5) , MARILENA BĂTĂIOSU 6) , MAGDALENA NATALIA DINA 7) , CLAUDIU MĂRGĂRITESCU 8) , MIHAELA JANA ŢUCULINĂ 9) , OANA-CELLA ANDREI 5)
This is a cross-sectional retrospective study of observational type. 157 menopausal subjects were included. A number of N1=89 were younger of 60 years old (also included) and a number of N2=68 were older than 60 years old. Median of age was of 55 years, respective 66 years.The biochemical parameters like total and ionic serum calcium, serum magnesium, and phosphorus between the two groups N1-N2 were similar (p]0.05).The median values of mentioned chemical elements were within normal limits.The bone turnover markers were not statistically significant different between N1 and N2. 25OHD was found deficient in both populations, irrespective of age. DXA- BMD and T-score N1-N2 difference was statistical significant for all the four central sites. Biochemical mineral parameters seem not to be influenced by the cut off of 60 years in menopausal women aged between 40 and 80 years. Yet, a large prevalence of hypovitaminosis D is identified regardless the age without secondary PTH raise. The statistical significant results are for BMD and T-score for all the four central sites.
Adenoid cystic carcinoma (ACC) is the second most common malignant salivary glands neoplasms with a controversial biological behavior. Even though these tumors grow slowly, they have increased potential for recurrence and distant metastasis. In order to elucidate this behavior, our study aimed to investigate the immunoexpression in such tumors of the most important transcriptional factors [Twist, Snail, Slug, and zinc finger E-box binding homeobox 1 (ZEB1)] involved in the epithelial–mesenchymal transition process. The highest level of expression was recorded for Twist, present in all the investigated cases, followed by the Slug and Snail, while no tumor parenchyma reactivity was noticed for the ZEB1 factor. There were tumor reactivity differences regarding topography, histopathological variant, and nerve and lymph node invasion status. Thus, tumors developed from the intraoral minor salivary glands, with solid pattern, perineural invasion, locally aggressive and with lymph node metastasis were the most reactive. Therefore, these transcription factors could be useful as prognostic biomarkers and efficient therapeutic targets in such salivary malignancies.
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