1.Effect of artificial aging on optical properties of ultra-translucent zirconia ceramics of different brands
Luona CHEN ; Xin ZHANG ; Zhengyu TIAN ; Jian WANG
West China Journal of Stomatology 2024;42(3):353-358
Objective This work aimed to evaluate the effect of artificial aging on the translucency and color differ-ence(ΔE)of ultra-translucent zirconia and provide a reference for clinical application.Methods The discs of ultra-translucent zirconia from six brands(Wieland,3M ESPE,Amann Girrbach,Kuraray Noritake,Upcera,and Besmile)were cut and sintered according to each manufacturer's product instructions;the experimental groups were named ZNT,LVP,AG,KAT,UPC,and BSM,respectively.IPS e.max Press was used as the control group(PLT).The specimens(n=6)were prepared with a diameter of 14 mm and a thickness of 1 mm.The specimens were subjected to artificial aging treat-ment according to the following conditions:in an auto-clave at 134℃ at 0.2 MPa for 4,8,and 12 h.According to the CIE1976Lab system,the CIE L*,a*,and b* values of the specimens before and after aging were measured by a co-lorimeter.The translucency parameter(TP)and ΔE were calculated.Results The mean TP values of each group before aging inorder were PLT>KAT>AG>ZNT>BSM>UPC>LVP.We found no significant difference in translu-cency in all experimental groups after aging for 4 and 8 h compared with those before aging.After 12 h of aging,the TP values of the KAT and ZNT groups were not significantly different from those before aging,but the TP values of the AG,BSM,LVP,and UPC groups were significantly lower than those before aging(P<0.05).The TP value of the control group was significantly higher than that of the other experimental groups at different stages(P<0.05).ΔE=3.3 was con-sidered the visible color difference,and ΔE was less than 3.3 in all groups after 4 h of aging.After aging for 8 h,ΔE of the UPC group was slightly higher than 3.3.ΔE of the BSM and UPC groups was greater than 3.3 after 12 h of aging.Conclusion The TP and ΔE of different brands of ultra-translucent zirconia may change after various aging times.The translucency of some zirconia showed a decreasing trend and the color difference showed an increasing trend with the aging time.
2.Evaluation of an integrated teaching model of oral preclinical practice based on endodontic-restorative sequential treatment
CHEN Luona ; WANG Jian ; ZHANG Xin
Journal of Prevention and Treatment for Stomatological Diseases 2023;31(12):883-888
Objective:
Evaluate the effect of an integrated teaching model of oral preclinical practice based on endodontic-restorative sequential treatment to provide a reference for the exploration of the teaching mode of the stomatology specialty.
Methods :
This retrospective study was reviewed and approved by the Ethics Committee. The study was divided into 2 groups. There were 450 2018-grade and 2019-grade students in the discipline integration teaching method (DIT) group, and a preclinical practice course (root canal therapy and fixed prosthetic treatments were integrated into an endodontic-restorative sequential treatment) using the DIT method was applied. There were 443 2016-grade and 2017-grade students in the traditional teaching method (TT) group, and a TT preclinical practice course (root canal therapy and fixed prosthetic treatments training courses were taught separately) was applied. Both groups were taught by the same two teachers. The scores of clinical skills examination and treatment planning were compared between the two groups. In addition, students in the two groups were asked to complete the questionnaires about the teaching methods, and students in Group DIT and their teachers were asked to complete the questionnaires on their degree of satisfaction with the DIT method in the preclinical course.
Results :
Students in the DIT group had an average score of 90.2 ± 4.16 in the practical skill evaluation, which was higher than that of the TT group (86.3±3.57) (P = 0.001). In the case analysis, 91.8% (413/450) of the students in the DIT group successfully planned the treatment, compared to a significantly lower rate in the TT group of 74.7% (331/443) (P = 0.001). The questionnaire results showed that recognition degrees of cultivated clinical thinking, improved indication analysis ability, improved operational skills, stimulated enthusiasm for learning, and improved autonomous learning were higher in the DIT group than in the TT group, and both teachers (2/2) and 98.4% (443/450) of students recognized the DIT method.
Conclusions
The DIT method significantly improved students’ learning quality and ability, proved effective in the endodontic-restorative sequential treatment practice course and was more acceptable to teachers and students. The DIT method is more effective than the TT method in improving students’ clinical thinking and operation ability.
3.Effect of emotional freedom technique on perceived stress, anxiety and depression in cancer patients: a preliminary experiment
Jinjin LIU ; Luona YANG ; Jingjing CHEN
Modern Clinical Nursing 2017;16(10):34-38
Objective To evaluate the effect of emotional freedom technique (EFT) on the levels of perceived stress, anxiety and depression in cancer patients. Methods Fifteen cancer patients received the intervention of EFT once per day for one week. The effect was evaluated with the Chinese version of perceived stress scale (CPSS), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) before and after the intervention. Result The total scores of SAS, CPSS and SDS after the intervention were significantly lower than those before the intervention (P<0.01). Conclusion EFT can effectively reduce the levels of perceived stress, anxiety and depression in cancer patients.
4.Pathogenic bacteria distribution and drug resistance in one hundred children of bacterial meningitis
Luona LIN ; Li LIN ; Shunhang WEN ; Xiuzhen CHEN ; Yanping SHANG ; Changchong LI
Journal of Clinical Pediatrics 2016;(2):107-112
Objective To investigate the pathogenic bacteria distribution, antibiotics resistance, and clinical features of childhood bacterial meningitis (BM). Methods Clinical data from BM children with positive cerebrospinal lfuid culture were retrospectively analyzed from March 2004 to March 2015. According to age, the BM children were divided into neonates group (0-28 days), infants group (—1 year), and children group (≥1 year). According to the onset time, the BM children were divided into the early group (March 2004 to March 2010) and the late group (April 2010 to March 2015). According to the clinical situation, the BM children were divided into the trauma and surgery secondary infection group and the control group. Results A total of 100 BM children were recruited. One hundred and two strains of pathogens were detected, 62 (60.8%) strains of Gram positive bacteria and 40 (39.2%) strains of Gram negative bacteria. The main pathogens were Streptococcus pneumoniae (33 strains), Escherichia coli (22 strains), and Streptococcus agalactiae (10 strains). The proportion of Streptococcus agalactiae was higher in the late group (18.8%(9 cases)) than that in the early group (1.9%(1 case)) (χ2=6.406, P=0.011). The proportion of coagulase-negative staphylococci was higher in the trauma and surgery secondary infection group than that in the control group (χ2=6.631, P=0.010). Drug sensitivity analysis found that 60.0%of Escherichia coli produced extended-spectrumβ-lactamases (ESBLs) in the control group, while the only one strain of Escherichia coli in the trauma and surgery secondary infection group was ESBLs negative. Streptococcus pneumoniae were sensitive to vancomycin and linezolid. Streptococcus agalactiae were all found in the control group, which were all sensitive to penicillin and linezolid. The sensitive rate to vancomycin was only 70%. The incidence of complications in neonates group, infants group, and children group was 55.0%(22/40), 78.6%(33/42), and 33.3%(6/18), respectively. The difference was statistically signiifcant (χ2=11.848, P<0.05). The most common complications in these three age groups were ventricular dilatation (40.9%), subdural effusion (45.5%), and hydrocephalus (40.0%), respectively. Thirty-ifve children were cured, 41 children were improved and discharged, 22 children were not cured and left the hospital, and 2 children died. Conclusions Streptococcus pneumoniae, Escherichia coli, and Streptococcus agalactiae were the predominant pathogens in childhood BM. The Streptococcus agalactiae infection is increased in the late group. The complications is varied in different age groups..


Result Analysis
Print
Save
E-mail