Factors affecting job satisfaction of dental hygienists related to foreign dental health services / 대한구강보건학회지

Objectives@#This study aimed to determine the relationship between English communication ability and job satisfaction of dental hygienists involved in the process of providing dental health services to foreigners and to analyze factors related to job satisfaction. @*Methods@#Both online and offline surveys were conducted in parallel to measure English communication competency and job satisfaction. Participants were 195 clinical dental hygienists provided dental health services to foreigners. Spearman’s rho analysis was performed on the correlation between English communication ability, and job satisfaction, and a stepwise multiple regression analysis was performed on the factors related to the job satisfaction of the dental hygienist. @*Results@#The job satisfaction of dental hygienists was 2.99 point out of 5 points. There was a strong positive relationship between English communication ability and english communication frequency (r=0.682), and the higher the English communication ability, the higher the job satisfaction (r=0.357).Factors affecting job satisfaction were English communication ability (β=0.378,P<0.001) and foreign medical assistance (β=0.391, P<0.001). The adjusted explanatory power of this model was 34.9%. @*Conclusions@#The job satisfaction of dental hygienists who provided dental health services to foreigners was low. English communication ability and experience in foreign medical assistance were significant influencing factors of job satisfaction. These results suggest that education for improving the English communication skills of dental hygienists should be strengthened.

Factors affecting job satisfaction of dental hygienists related to foreign dental health services / 대한구강보건학회지

Objectives@#This study aimed to determine the relationship between English communication ability and job satisfaction of dental hygienists involved in the process of providing dental health services to foreigners and to analyze factors related to job satisfaction. @*Methods@#Both online and offline surveys were conducted in parallel to measure English communication competency and job satisfaction. Participants were 195 clinical dental hygienists provided dental health services to foreigners. Spearman’s rho analysis was performed on the correlation between English communication ability, and job satisfaction, and a stepwise multiple regression analysis was performed on the factors related to the job satisfaction of the dental hygienist. @*Results@#The job satisfaction of dental hygienists was 2.99 point out of 5 points. There was a strong positive relationship between English communication ability and english communication frequency (r=0.682), and the higher the English communication ability, the higher the job satisfaction (r=0.357).Factors affecting job satisfaction were English communication ability (β=0.378,P<0.001) and foreign medical assistance (β=0.391, P<0.001). The adjusted explanatory power of this model was 34.9%. @*Conclusions@#The job satisfaction of dental hygienists who provided dental health services to foreigners was low. English communication ability and experience in foreign medical assistance were significant influencing factors of job satisfaction. These results suggest that education for improving the English communication skills of dental hygienists should be strengthened.

Biocompatibility and Bioactivity of Four Different Root Canal Sealers in Osteoblastic Cell Line MC3T3-El / 치위생과학회지

Background@#Endodontic sealers or their toxic components may become inflamed and lead to delayed wound healing when in direct contact with periapical tissues over an extended period. Moreover, an overfilled sealer can directly interact with adjacent tissues and may cause immediate necrosis or further resorption. Therefore, the treatment outcome conceivably depends on the endodontic sealer’s biocompatibility and osteogenic potential. This study aimed to evaluate the cell viability and osteogenic effects of four different sealers in osteoblastic cells. @*Methods@#AH Plus (resin-based sealer), Pulp Canal Sealer EWT (zinc oxide-eugenol sealer), BioRoot RCS (calcium silicate-based sealer), and Well-Root ST (MTA-based calcium silicate sealer) were mixed strictly according to the manufacturer’s instructions, and dilutions of sealer extracts (1/2, 1/5 and 1/10) were determined. Cell viability was measured using the water-soluble tetrazolium-8 (WST-8) assay. Differentiation was assessed by alkaline phosphatase (ALP) activity and mineralized nodule formation by Alizarin Red S staining. @*Results@#The cell viability of the extracts derived from the sealers excluding Well-Root ST was concentration dependent, with sealer extracts having the least viability at a 1/2 dilution. At sealer extract dilution of 1/10, the test groups showed the same survival rate as that control group, with the exception of BioRoot RCS. Among all experimental groups, BioRoot RCS showed the highest cell viability after 48 hours. The ALP activity was significantly higher in a concentration-dependent manner. Furthemore, all four materials promoted ALP activity and mineralized nodule formation compared to the control at 1/10 dilutions. @*Conclusion@#This is the first study to highlight the differences in biological activity of these four materials. These results suggest that the composition of root canal sealers appears to alter the form of biocompatibility and osteoblastic differentiation.

Baicalein Treatment Promotes Osteoblast Proliferation and Osteogenic Differentiation through Activation of Immediate Early Response 3 / 치위생과학회지

BACKGROUND: The primary aims of periodontal disease treatment is to remove dental plaque and calculus, the main causes of tooth loss, and restore periodontal tissue destroyed by inflammation. Periodontal disease treatment should also help maintain the alveolar bone, alleviate inflammation, and promote periodontal ligament cell proliferation, which is essential for tissue regeneration. Conventional antibiotics and anti-inflammatories have adverse side effects, especially during long-term use, so there is a need for adjunct treatment agents derived from natural products. The purpose of this study was to investigate whether the herbal flavone baicalein has the osteogenic activity under inflammatory conditions, and assess the involvement of osteoblast immediate early response 3 (IER3) expression.METHODS: Human osteoblastic MG-63 cells were cultured with the pro-inflammatory cytokines tumor necrosis factor α and interleukin 1β in the presence and absence of baicalein. Proliferation was assessed using the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay, and expression of IER3 mRNA was assessed using real-time polymerase chain reaction. The expression of IER3 protein levels and activation of associated signal transduction pathways were assessed using western blotting.RESULTS: Baicalein increased IER3 mRNA and protein expression synergistically. In addition, baicalein reversed the suppression of cell proliferation, and the downregulation of osteogenic transcription factor runt-related transcription factor 2 and osterix induced by pro-inflammatory cytokines. Baicalein also upregulated the phosphorylation of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK 1/2). The upregulation of IER3 by pro-inflammatory cytokines was blocked by pretreatment with inhibitors of AKT, p38, JNK, and ERK 1/2.CONCLUSION: Baicalein mitigates the deleterious responses of osteoblasts to pro-inflammatory cytokines. Further, IER3 enhanced the effect of baicalein via activation of AKT, p38, JNK, and ERK pathways.

Protective Effects of Ursolic Acid on Osteoblastic Differentiation via Activation of IER3/Nrf2 / 치위생과학회지

BACKGROUND: Oxidative stress is a known to be associated with in the pathogenesis of many inflammatory diseases, including periodontitis. Ursolic acid is a pentacyclic triterpenoid with has antimicrobial, antioxidative, and anticancer properties. However, the role of ursolic acid in the regulating of osteogenesis remains undetermined. This study was aimed to elucidate the crucial osteogenic effects of ursolic acid and its ability to inhibit oxidative stress by targeting the immediate early response 3 (IER3)/nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. METHODS: Cell proliferation was determined using water-soluble tetrazolium salt assay, cell differentiation was evaluated by alkaline phosphatase (ALP) activity, and formation of calcium nodules was detected using alizarin red S stain. Generation of reactive oxygen species (ROS) was determined using by DCFH-DA fluorescence dye in hydrogen peroxide (H₂O₂2)-treated MG-63 cells. Expression levels of IER3, Nrf2, and heme oxygenase-1 (HO-1) were analyzed using western blot analysis. RESULTS: Our results showed that ursolic acid up-regulated the proliferation of osteoblasts without any cytotoxic effects, and promoted ALP activity and mineralization. H₂O₂-induced ROS generation was found to be significantly inhibited on treatment with ursolic acid. Furthermore, in H₂O₂-treated cells, the expression of the early response genes: IER3, Nrf2, and Nrf2-related phase II enzyme (HO-1) was enhanced in the presence of ursolic acid. CONCLUSION: The key findings of the present study elucidate the protective effects of ursolic acid against oxidative stress conditions in osteoblasts via the IER3/Nrf2 pathway. Thus, ursolic acid may be developed as a preventative and therapeutic agent for mineral homeostasis and inflammatory diseases caused due to oxidative injury.

Gender Differences in Aggression-related Responses on EEG and ECG

Gender differences in aggression viewed from an evolutionary and sociocultural perspective have traditionally explained why men engage in more direct and physical aggression, and women engage in more indirect and relational aggression. However, psychological and behavioral studies offer inconsistent support for this theory due to personal or social factors, and little is known about the gender-based neurobiological mechanisms of aggression. This study investigates gender differences in aggression through an analysis of electroencephalography (EEG) and electrocardiography (ECG) based neurobiological responses to commonly encountered stimuli, as well as psychological approaches in healthy Korean youth. Our results from self-reports indicate that overall aggression indices, including physical and reactive/overt aggression, were stronger in men. This agrees with the results of previous studies. Furthermore, our study reveals prominent gender-related patterns in γ signals from the right ventrolateral frontal cortex and changes in heart rate through stimulation by aggressive videos. In particular, gender differences in EEG and ECG responses were observed in response to different scenes, as simple aversion and situation-dependent aggression, respectively. In addition, we discovered decisive gender-distinct EEG signals during stimulation of the situation-dependent aggression regions within the right ventromedial prefrontal and ventrolateral frontal regions. Our findings provide evidence of a psychological propensity for aggression and neurobiological mechanisms of oscillation underlying gender differences in aggression. Further studies of oscillatory responses to aggression and provocation will expand the objective understanding of the different emotional worlds between men and women.

JAK/STAT Pathway Modulates on Porphyromonas gingivalis Lipopolysaccharide- and Nicotine-Induced Inflammation in Osteoblasts / 치위생과학회지

Bacterial infection and smoking are an important risk factors involved in the development and progression of periodontitis. However, the signaling mechanism underlying the host immune response is not fully understood in periodontal lesions. In this study, we determined the expression of janus kinase (JAK)/signal transducer and activator of transcription (STAT) on Porphyromonas gingivalis lipopolysaccharide (LPS)- and nicotine-induced cytotoxicity and the production of inflammatory mediators, using osteoblasts. The cells were cultured with 5 mM nicotine in the presence of 1 µg/ml LPS. Cell viability was determined using MTT assay. The role of JAK on inflammatory mediator expression and production, and the regulatory mechanisms involved were assessed via enzyme-linked immunosorbent assay, reverse transcription-polymerase chain reaction, and Western blot analysis. LPS- and nicotine synergistically induced the production of cyclooxgenase-2 (COX-2) and prostaglandin E₂ (PGE₂) and increased the protein expression of JAK/STAT. Treatment with an JAK inhibitor blocked the production of COX-2 and PGE₂ as well as the expression of pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin-1β (IL-1β), and IL-6 in LPS- and nicotine-stimulated osteoblasts. These results suggest that JAK/STAT is closely related to the LPS- and nicotine-induced inflammatory effects and is likely to regulate the immune response in periodontal disease associated with dental plaque and smoking.