Bacteriophages possess the ability to infect and kill bacteria and have now been applied in various oral diseases,providing new insights for the prevention and treatment of oral diseases.They are expected to become a novel biological antibacterial agent for treating oral diseases.This paper comprehensively discusses the application of bacteriophages in oral medicine from six aspects:the concept and application prospects of bacteriophages,four common infectious diseases of the oral cavity and their pathogenic bacteria,existing treatment methods,and the application and outlook of bacteriophages in these diseases.Lay a theoretical basis for the clinical implementation of phage therapy.

Objective To understand the changes in self-rated health among middle-aged and elderly individuals in China and the influencing factors,providing a reference for improving health and promoting healthy aging.Methods Using data from the China Health and Aged Care Tracking Survey(CHARLS)from 2011 to 2020,this study analyzed 3595 middle-aged and elderly individuals(≥45 years old)who participated in all five rounds of the survey from 2011 to 2020.Univariate analysis and multinomial logistic regression were employed to analyze the influencing factors of self-rated health changes.Results Among the 3 595 middle-aged and elderly individuals,26.54％reported an increase in self-rated health,28.40％reported a decrease,and 45.06％reported no change.The multinomial logistic regression results indicated that compared to those with unchanged self-rated health,individuals whose self-rated health declined were more likely to have an increased number of Activities of Daily Living(ADLs),a higher number of chronic diseases,not engaging in at least 10 minutes of light physical activity per week,and a decline in life satisfaction levels.The odds ratios for these factors were 1.415(OR=1.415,95％CI:1.181～1.694),1.479(OR=1.479,95％CI:1.225～1.785),1.454(OR=1.486,95％CI:1.172～1.804),and 1.263(OR=1.237,95％CI:1.043～1.530),respectively.In contrast,individuals whose self-rated health improved,compared to those with unchanged health,were more likely to report an increase in life satisfaction levels,while an increase in ADLs and chronic diseases negatively impacted self-rated health improvement.The odds ratios for these factors were 1.698(OR=1.698,95％CI:1.425～2.023),0.769(OR=0.769,95％CI:0.646～0.915),and 0.689(OR=0.689,95％CI:0.549～0.865),respectively.Conclusion From 2011 to 2020,the self-rated health of middle-aged and elderly individuals in China has slightly declined,with a focus on improving physical health status,increasing physical activity,and addressing mental health as key areas for enhancing self-rated health among the elderly in China.

The preparation edge of the tooth in oral restoration has always been the hot concern for dentists,and the improper preparation edge may lead to such diseases as caries and periodontitis,and ultimately lead to the restoration failure.The application of biologically oriented preparation technique has been proven to restore good periodontal soft and hard tissue morphology,which is expected to replace the traditional dental preparation methods.This article aims to comprehensively discuss the application of biologically oriented preparation technique in veneers,full crown and implantation.

Objective To study the application value of CAD/CAM technology in the teaching of inlay manufacturing.Methods A total of 60 undergraduates interned in the Department of Stomatology,Yan'an Hospital,Kunming Medical University were randomly divided into an experimental group(n=30)and a control group(n=30).We selected appropriate clinical cases for students to prepare for mandibular molar's proximal occlusal inlays.The instructor guided the results of the first preparation in different ways,and the students made the second modification and preparation,and the assessment team scored and evaluated the five aspects of the final preparation,the shape of the preparation,the shape of the occlusal surface,the dovetail retention,and the adjacent surface.Results The scores of all detection indexes in the experimental group were higher than those in the control group(P<0.05).Conclusion The application of CAD/CAM technology in inlay manufacturing teaching can effectively improve students'clinical hands-on ability and achieve better teaching effects than traditional teaching methods.

Objective To investigate the status of perceived discrimination among HIV-infected people receiving antiviral treatment and analyze its influencing factors,so as to provide reference for reducing discrimination and improving the life quality of HIV-infected people.Methods The multi-stage stratified cluster sampling method was used to select HIV-infected individuals from designated hospitals in three cities and counties in Yunnan Province,as well as from designated township health centers,for face-to-face survey interviews.The questionnaire included socio-demographic characteristics,AIDS infection disease characteristics,Berger AIDS perceived discrimination Scale and Xiao Shui Yuan Social Support Rating Scale.The influencing factors of perceived discrimination were analyzed by multiple linear regression.Results There were 633 valid questionnaires.The perceived discrimination score of HIV-infected people was(111.11±19.43),which was at a medium high level,and the dimension with the highest average score was fear of publicity.Multiple regression showed that middle-aged people,those who do not participate in group activities and those who have less social support had higher perceived discrimination(P＜0.05).Conclusion The perception discrimination of AIDS patients in Yunnan Province is high.In the prevention and control of AIDS,it is necessary to actively organize and participate in group activities,improve social support and pay attention to middle-aged AIDS patients.

Objective To do screening acute lymphoblastic leukemia patients scFv antibody single chain variable region to cre-ate conditions for the expression and obtain further specificity of antibody fragments.Methods In this study,patients with newly diagnosed acute lymphoblastic leukemia serum as coating antigen using phage display technology,screening phage an-tibody specificity from the semi-synthetic human phage antibody libraries,the first to target the immune antigen-coated tab-let,phage library was added,so that with the target antigen-specific binding phage antibody was immobilized on plates immu-nization,could not be specifically bound phages were rinsed.The eluted specific binding phage,E.coli infection.Could get the specific antibody gene containing phagemid.Results After three “adsorption-elution-amplification”screening process,got stronger leukemia patient antigen-specific phage antibody variable region fragment and identification.Conclusion Got better strain affinity antibody fragments,to create the conditions for the next fragment expression,identification and clinical appli-cation.

Objective To screen permethrin human single-chain variable region (scFv) antibody for aims of developing rapid detection kit. Methods Phage display technology was used in this study. Permethrin was solid phase coated on Nunc plate as antigen. Semi-synthetic single-chain variable region of human antibody library technology was applied, and single chain variable region was screened from phage antibody library after 3 rounds "adsorption - elution - amplification" of the selection process. 100 clones were random selected as resistance to permethrin clones , enzyme-linked immunosorbent assay (ELISA), crossreactivity and competitive inhibition experiments were used to validate permethrin binding activity with strong scFv clones from the selected phage antibody clones plasmid. The plasmid was digested with restriction enzyme Sfi Ⅰ / Not Ⅰ and subcloned into pCANTAB5E vector. After transformed into E. coli XL1BIue, the plasmid was identified by restriction enzyme analysis. Results After screening in 100 clones, 18 clones had high ELISA absorbance values ( A value) at 490nm wavelength ( A490nm), then bovine serum albumin (BSA) cross-reactions identified five weak cross-reaction. Combined with the triplicate ELISA and competitive inhibition experiment results, one positive clone was acquired at last. And this clone was subcloned into pCANTAB5E vector and transformed into competent cells XL1-Blue. Conclusion Plasmid fragment was consistent with the purpose, which provided the foundation for further study of its specific affinity.