Validation of the Polish version of the Johns Hopkins Learning Environment Scale-a confirmatory factor analysis.

The Johns Hopkins Learning Environment Scale (JHLES) was developed by Robert B. Shochet, Jorie M. Colbert and Scott M. Wright of the Johns hopkins university school of medicine and consists of 28 items used to evaluate perception of the academic environment. The objective was to translate and adapt the JHLES to Polish cultural conditions and to validate the Polish version of the tool. The JHLES questionnaire was completed by students of all years (first-fifth) of the faculties of dental medicine at the Medical University of Lublin and the Medical University of Gdansk. The total surveyed population consisted of 597 students. The overall reliability of the tool was excellent. Confirmatory factor analysis was performed in order to confirm structural consistency with the original JHLES tool. Consequently, all indices had acceptable values (close to 1 or 0, depending on the case), and there was consistency in the results, which shows that the JHLES model is supported by the data. In the present study, the JHLES has been validated in a sample of dental students for the first time in Poland and Europe. Our study provided good evidence for the reliability and validity of the Polish version of the JHLES. In conclusion, the Polish-language version of the JHLES questionnaire is a reliable and valid instrument for analysing the learning environment for students, and its factor structure is supported by the data.

Validation of the Polish version of the DREEM questionnaire - a confirmatory factor analysis.

AIM: The aim of our study was to translate and adapt the Dundee Ready Education Environment Measure (DREEM) questionnaire developed by Roff et al. to the cultural conditions in Poland and also to validate it. Studying the learning environment is beneficial because it can identify students' perceptions of their environment and support the staff in reflecting on, planning for and combining proper teaching approaches to improve it. METHODS: The DREEM questionnaire was completed by students of all years (first-fifth) in the faculties of dental medicine at the Medical University of Lublin and the Medical University of Gdansk. The total surveyed population consisted of 650 students. Validity was separated into four phases: (1) translation validity, (2) confirmatory factor analysis, (3) concurrent validity and (4) criterion-related validity. RESULTS: Our study confirmed the original structure of the DREEM tool (GFI = 0.955, AGFI = 0.951, NFI = 0.931, TLI = 0.962, CFI = 0.964, RNI = 0.964, IFI = 0.964, RFI = 0.928, PNFI = 0.885, SRMR = 0.062, RMSEA = 0.043, 90% CI = 0.041-0.046) and obtained very good reliability rates, with Cronbach's alpha > 0.7 for all scales. Only Subscale V achieved a lower Cronbach's alpha of > 0.5. The study was conducted using the test-retest method, which is why the intraclass correlation coefficients for reliability were also calculated; individual items showed both medium and good correspondence. CONCLUSIONS: Our study provided good evidence for the reliability and validity of the Polish version of the DREEM. In conclusion, the Polish-language version of the DREEM questionnaire is a reliable and valid instrument for analysing the learning environment for dental students and its factor structure is supported by the data.

Predictors of stress among dentists during the COVID-19 epidemic.

The aim of the study was to assess the relationship between personality traits, self-esteem and life satisfaction, and also the stress level, among dentists during the COVID-19 outbreak. In order to confirm our hypotheses, 310 active dentists aged 25-64 years who were practising during the first wave of COVID-19 in Poland were examined. The IPIP-BFM-20 self-report questionnaire was used to measure personality traits, the popular Rosenberg Self-Esteem Scale was used to assess self-esteem, the five-item Satisfaction with Life Scale was used to measure life satisfaction and the four-item version of the Perceived Stress Scale was used to measure stress. The dependent variable-stress-correlates negatively with traits in relation to the dimensions of extraversion (r = -0.17, p < 0.01), emotional stability (r = -0.35, p < 0.01) and intellect (r = -0.16, p < 0.01); it also has a negative correlation with self-esteem (r = -0.37, p < 0.01) and life satisfaction (r = -0.35, p < 0.01). Among the analysed variables, the highest correlations are observed for the following: self-esteem and emotional stability (r = 0.51, p < 0.01); self-esteem and life satisfaction (r = 0.49, p < 0.01); extraversion and intellect (r = 0.47, p < 0.01). Considering the measures of mediation relevance and pathway relevance, it can be assumed that both self-esteem and life satisfaction have a mediating function in the relationship between agreeableness, emotional stability and stress: the relationship between emotional stability and stress is negative whereas that between agreeableness and stress is positive.

How the Duration and Mode of Photopolymerization Affect the Mechanical Properties of a Dental Composite Resin.

Composite materials are the most common materials in use in modern dentistry. Over the years, the methods of photopolymerization of composite materials have been improved with the use of various devices, such as quartz tungsten halogen lamps (QTHs), light-emitting diode units (LEDs), plasma-arc lamps and argon-ion lasers. This study aimed to compare the mechanical properties of a composite material, depending on the time and mode of photopolymerization. One hundred and forty rectangular specimens (25 × 2 × 2 mm) and forty-two disc-shaped samples (5 mm diameter and 2 mm thickness) were prepared from shade A2 Boston composite resin. Samples were cured using the following seven photopolymerization protocols: four fast-cure modes (full power for 3, 5, 10, and 20 s), two pulse-cure modes (5 and 10 shots of 1 s exposures at full power), and one step-cure mode (soft start with a progressive cycle lasting 9 s). Specimens were subjected to a flexural strength test, Vickers microhardness test, and FTIR spectroscopy test. A 2-factor ANOVA and post-hoc tests were carried out to assess the differences in the flexural strength parameter between the tested groups of samples before and after aging. A mixed-model ANOVA was carried out to assess the differences in the Vickers microhardness parameter between the tested groups of samples before and after aging. The lowest values of flexural strength (p < 0.001) and Vickers microhardness (p < 0.001) were obtained for the 3 s mode for the pre- and post-aging groups. The FTIR mapping tests showed a much more homogeneous chemical structure of the composite after 20 s of continuous irradiation, compared to the sample irradiated for 5 s in the continuous mode. The mode and cure time affects the mechanical properties of the composite resin. Appropriate selection of the cure mode and time ensures better mechanical properties of composite resin. This suggests that the survival of dental restorations within the oral cavity could be extended by using longer photopolymerization durations.

The Influence of Popular Beverages on Mechanical Properties of Composite Resins.

Currently, composite resins are used in many restorative procedures. Previous studies showed that drinking beverages may affect the mechanical properties such as microhardness or flexural strength of dental composite resins. The aim of the present study was to investigate the influence of common beverages on the mechanical properties of composite resins. Samples of the materials were prepared according to the ISO 4049:2010 standard and producer's recommendations. The samples were next conditioned in tested fluids: distilled water, sparkling water, Coca-Cola, Red Bull and orange juice for 7 days. Vickers microhardness and flexural strength testing was performed after 7 days. Performed statistic tests confirmed the significance of microhardness changes of the tested materials in terms of both different conditioning of the samples and different composite materials. The mean flexural strength of composites was highest in distilled water and it was reduced after one week in different beverages. We conclude that all tested beverages influenced on Vickers microhardness of tested composite resins. Flexural strength only in one material was statistically significantly influenced by tested beverages. The results of this study should be taken into consideration by a dentist preparing recommendations for the patients after dental treatment with usage of composite material or after cementing composite based fixed dentures.

Vitamin D3 and Dental Caries in Children with Growth Hormone Deficiency.

Vitamin D deficiency is a common risk factor for multifactorial diseases, and it seems to be associated with growth hormone deficiency (GHD). Vitamin D could prevent dental caries. The goal of this study was to identify whether there is an association between hormonal therapy with growth hormone (GH), vitamin D3 supplementation, vitamin D3 levels, and the occurrence of caries among children affected by GHD. The study group consisted of patients from the Department of Endocrinology and Diabetology of the University Paediatric Hospital at the Medical University of Lublin treated with recombinant human GH for pituitary GHD. It was conducted between October 2014 and June 2015. The study group included 121 children and adolescents aged 6 to 18 years, with 56 children from rural areas and 65 from urban areas. The study group was stratified by the area of residence. We found the statistically significant impact of vitamin D3 concentration on the average value of the DMFT (decayed, missed, and filled teeth) index and its component-DT (decayed teeth), which was noted in subjects from rural areas. Among patients from urban areas, we found a statistically significant correlation between duration of therapy and the DMFT index. An increase in duration of GH therapy by 10 months leads to a mean increase in DMFT index by 0.70. Based on multiple regression analysis, we developed the following model: value of DT = 3.10 - 0.73∗category of vitamin D3 concentration - 0.07∗duration of supplementation (in months). In this model, variables with a significant impact on the value of DT in the group of patients from rural areas include time of vitamin D3 supplementation and category of vitamin D3 concentration. Greater emphasis should be placed on promoting vitamin D3 as a potentially effective agent reducing the number of dental caries, especially among patients with GHD.

Dental caries and vitamin D3 in children with growth hormone deficiency: A STROBE compliant study.

Vitamin D may prevent dental caries. To date, no attempts have been made to examine the correlation between the incidence of caries and the concentrations of vitamin D in children with pituitary growth hormone deficiency.The study observed patients of the Department of Endocrinology and Diabetology of the University Paediatric Hospital of the Medical University of Lublin treated with human recombinant growth hormone for pituitary growth hormone deficiency (GHD). The study was conducted between October 2014 and June 2015. The study group consisted of 121 children and adolescents (6-17 years old), including 56 children from rural areas and 65 children from urban areas. The study group was stratified by area of residence.In our study, the increase in vitamin D3 [25(OH)D] levels reduced the D component by 0.66 per each 10 ng/mL of vitamin D3 concentration. The percentage of children with active caries in rural areas is 91.07% (n = 51), which is significantly higher than the percentage of children with active caries in urban areas (81.54%, n = 53).To date, information regarding the potential possibility of reducing the incidence of dental caries by means of increasing the levels of vitamin D was sidelined by paediatricians and dentists alike. Therefore, this aspect of caries prevention should be highlighted.

Different association between specific manifestations of bruxism and temporomandibular disorder pain.

INTRODUCTION: A growing body of evidence suggests that bruxism exists in two separate manifestations. However, little is known about the association between specific manifestations of bruxism and temporomandibular disorder (TMD) pain. AIM: The aim of our study was to analyze the association between TMD pain and specific diagnoses of bruxism (sleep, awake, and mixed diagnosis of sleep and awake bruxism). MATERIAL AND METHODS: 508 adult patients (296 women and 212 men), aged between 18 and 64 years (mean age 34±12 years), attending to a clinic for general dental treatment. Patients were asked to fill an anonymous questionnaire, consisting of three questions, verifying the presence of TMD pain and two forms of bruxism. All questions were based on the Polish version of the Research Diagnostic Criteria for Temporomandibular Disorders patient history questionnaire. Cross tabulation was done, and χ2 was used as a test of significance to find the association between the variables. RESULTS: Awake bruxism was associated with TMD pain only in men (χ2=7.746, p<0.05) while mixed diagnosis of bruxism was associated with TMD pain in both women (χ2=10.486, p<0.05) and men (χ2=4.314, p<0.05). There was no statistically significant association between sleep bruxism and TMD pain. Gender-related differences in the presence of all bruxism diagnoses were also statistically insignificant. CONCLUSIONS: Interaction between sleep and awake bruxism may increase the risk for TMD pain. We suggest considering concomitance as a confounder, when studying sleep or awake bruxism.

The dependence of dental caries on oral hygiene habits in preschool children from urban and rural areas in Poland.

INTRODUCTION: Dental caries is considered to be a modern civilization disease;however, the state of oral health negatively influences psychological and sociological relations in children which leads to feelings of discomfort from early age. OBJECTIVE: The aim of study was evaluation of the association between incidence of dental caries (d3ft index) in preschool children from urban and rural areas, and determining the relationship between dental caries intensity and hygienic habits. MATERIALS AND METHOD: 844 children aged 3-6 years from the city and the countryside were examined. The survey was conducted among parents/care givers regarding dental care of children. With parents' consent, the children had a dental examination. RESULTS: The incidence of caries was recorded at the level of 52.61%, with an average value of 4.31 on the d3ft index; however, for the children from the urban area this ratio amounted to 4.15, and in the countryside it reached the value of 4.7. A correlation was found between age and area of residence of the children and various components of hygienic behavior model. CONCLUSIONS: More than a half of the children had dental caries in combination with a high frequency of unsatisfactory hygiene needs. There is a relationship between oral hygiene habits and age of the children, depending on the place of residence.

[Correlation between generalized joint laxity and symptoms of temporomandibular disorders]. / Zwiazek miedzy wystepowaniem uogólnionej wiotkosci stawowej oraz zaburzen czynnosciowych ukladu ruchowego narzadu zucia.

UNLABELLED: Generalized joint hypermobility (GJH) is an increase of joints mobility over accepted norms. Many authors include GJH to etiologic factors of temporomandibular disorders (TMD). AIM: The aim of the study was to verify if there is an association between GJH and TMD. MATERIAL AND METHODS: Study was performed on 126 subjects (95 females and 31 males) aged 12-46 years. In order to find signs and symptoms of TMD Polish version of RDC/TMD questionnaire was used. GJH was assessed using Beighton's scale. Using r-Pearson's correlation an association between GHJ and TMD signs and symptoms was verified. RESULTS: No statistically significant association between TMD sings and symptoms and GJH was found. CONCLUSIONS: Presence of GJH is not associated with TMD signs and symptoms (in group of young adults).

Association between estrogen levels and temporomandibular disorders: a systematic literature review.

INTRODUCTION: To evaluate whether the hypothesis that estrogen levels are associated with temporomandibular disorders (TMD) in humans can be confirmed or contradicted by available literature. MATERIAL AND METHODS: A systematic review based on the content of PubMed, Scopus, and Cochrane Library databases was performed. Studies were identified using a combination of key words 'temporomandibular disorder' and 'estrogen'. Nine studies were included into our review. RESULTS: The relationship between estrogen levels and TMD was found in seven out of nine reviewed papers. Results from two papers suggest that a high estrogen level is associated with an increased prevalence of TMD. Five additional papers found a relationship between a low estrogen level and an increase in TMD pain. In considering the value of evidence and inconsistencies of results in the reviewed publications, we state that there is weak evidence to support the hypothesis that estrogen levels are associated with TMD. CONCLUSIONS: Results of reviewed studies were divergent and sometimes contradictory. One possible explanation is that estrogen influences TMD pain processing differently than temporomandibular joints (TMJ) structures, as shown in many animal studies. Estrogen may influence TMD pain processing differently than TMJ structures. We suggest consideration of the dual action of estrogen when planning future studies on its association with TMD.