Community diagnosis of dental caries in an urban community of Beijing / 中华全科医师杂志

Total 1188 subjects aged 35-74 in an urban community of Beijing were recruited by a multistage stratified random sampling procedure. Dental caries were examined by three dentists independently. The prevalence of dental crown caries was 79. 6% (DF), that of DMFS was 24. 39% and the root caries index (RCI) was 3.5% in this group. 22. 3% of the examinees required treatment for the crown caries and 26. 0% for root caries. Bivariate correlation analysis showed that DMFS was significantly correlated with RCI (P <0. 01 ), and there was no significant difference of DMFS and RCI between males and females. The study indicates that dental caries is a common health problem in adults and elderly population of urban Beijing, and the development of community oral health service system is necessary.

Thirty-nine-month xylitol chewing-gum programme in initially 8-year-old school children: a feasibility study focusing on mutans streptococci and lactobacilli.

AIM: To investigate the use of xylitol-containing chewing-gums in public elementary schools as a means to affect the growth of salivary and plaque mutans streptococci and salivary lactobacilli. DESIGN: Over a period of 24 months, 750 8- to 9-year-old children chewed xylitol (X group; n = 255) or xylitol-sorbitol (XS group; n = 264) gum on school days (454 days over 2 years), or chewed no gum at all (C group; n = 231). Consumption of xylitol in the X and the XS groups was 6.6 and 5.4g per day, respectively. Use of gum took place at school in four daily episodes of which three were supervised by teachers. Following the 24-month chewing-gum period, the subjects were re-examined after 15 months (total follow-up period: 39 months) at which time an extraneous comparison group (ExC; n = 117) was also examined. The numbers of subjects examined after 39 months were: X, 239; XS, 248; C3 217. METHODS: Salivary and plaque levels of mutans streptococci and the salivary levels of aerobically cultured aciduric bacteria (mostly representing lactobacilli) were determined using the Orion Diagnostica Dentocult SM and LB test kits, respectively. RESULTS: There were statistically significant differences after 24 and 39 months between the two xylitol chewing-gum groups and the C group with regard to salivary and plaque mutans streptococci and salivary lactobacilli: the use of xylitol-containing chewing-gums significantly reduced these bacterial scores. The reductions were statistically more significant in the X group than in the XS group. The bacterial scores of groups C and ExC were similar. CONCLUSIONS: Long-term use of xylitol-containing chewing-gum can reduce the growth of mutans streptococci in saliva and dental plaque, and lactobacilli-type bacteria in saliva, even if xylitol is used only on school days. The results also suggest that xylitol gum use can have a long-term, delayed growth-retarding effect on these micro-organisms, since reduced bacterial growth was still observed 15 months following the termination of xylitol use. The results indicate a close biochemical relationship between xylitol and mutans streptococci, and suggest that a similar relationship may exist regarding aerobically cultured aciduric bacteria present in saliva.

Effects of liposome-mediated endostatin gene transfection in vivo on inhibition of experimental choroidal neovascularization in rats / 第三军医大学学报

Objective To investigate the effects of liposome mediated intraocular gene transfection of endostatin on the inhibition of the development of choroidal neovascularization (CNV) in a rat model. Methods Experimental CNV model in Brown Norway rats was induced by laser photocagulation. The recombinant eukaryotic expression plasmid pSecTagA hEndostatin or control plasmid pSecTagA and liposome complexes were injected into the subretinal space of the model rats. In situ hybridization and immunohistochemical observation confirmed the presence of endostatin mRNA and protein expression two weeks after injection. Intraocular and serum levels of endostatin were measured by enzyme linked immunosorbent assay. The intensity of fluorescein leakage from the photocoagulated lesions was studied at 13 d after photocoagulation. The area of CNV was measured using high molecular weight FITC dextran (MW2?10 6) for high resolution angiography in RPE choroid sclera flat mounts. In addition, sections of CNV lesions were studied by light microscopy and endoglin (CD105) immunohistochemical evaluation. Results The retina, RPE, choroidal were infected by subretinal delivery of the pSecTag hEndostatin and expressed the endostatin. Two weeks after intraocular injection, the level of endostatin in the whole eye homogenates were (50 14?3 43) ng/eye and (31 5?2 21) ng/eye, respectively. Fluorescein leakage from the CNV lesions decreased significantly as compared with that in the control groups. The average area of CNV at the sites of the Bruch's membrane rupture showed significant difference in eyes injected with endostatin as compared with that in the control eyes. Endothelial cells demonstrated strong immunoreactivity of CD105 in CNV lesions in the control eyes. Conclusion Liposome mediated endostatin gene transfection can significantly inhibit the development of CNV.

Evaluation of the psychosocial status of students with dental fluorosis by parents and teachers / 实用口腔医学杂志

Objective:To study the psychosocial effect of fluorosis on students with dental fluorosis.Methods:115 students with different types of fluorosis were sampled randomly from fluorosis epidemic area of Xingtai city in Hebei province, including 60 of 12-year-old and 55 of 15-year-old students. Dental fluorosis was classified by Dean's Index (DI). Parents and teachers of the selected students were involved in a psychosocial questionnaire investigation which included five five-point questions, respectively.Results:Prevalence of fluorosis was 89.6% in the young students in the area. Evaluation scores by parents, which included “health of teeth”, “satisfaction of teeth” and “perceived well-being”, decreased with the decline of DI. Statistical difference was found in the answer to the five questions by parents when comparing the evaluation scores of control(without dental fluorosis) group,moderate dental fluorosis group and severe dental fluorosis group(P0.05). Difference of the evaluation scores of parents and teachers on boys and girls was not significant.Conclusion:Fluorosis has psychosocial impact on students, especially evaluated by parents.

Comparison of Dean's index and tooth surface index of fluorosis / 实用口腔医学杂志

Objective:To compare the characteristics of Dean's index(DI) and tooth surface index of fluorosis(TSIF). Methods:416 inhabitants of 12, 15 and 35~44 years old were sampled randomly to receive epidemiological survey assessed by DI in fluorosis endemic areas of Xingtai City, Hebei Province. Then TSIF was used to investigate the 178 samples selected randomly from the 416 subjects. Two examiners(S/C) were trained by an experienced specialist of epidemiology(W) before investigation. SPSS 10.0 software and Excel database were used to analyze the data.Results:Weighted Kappa of theoretic calibration of DI and TSIF was ranging from 0.86 to 0.96. The results of TSIF were lower than DI in clinical calibration test. With the increase of the number of tooth surfaces concerned, strength of agreement declined, ranging from “very good” to “moderate”. Prevalence of fluorosis according to DI was lower than that accoding to TSIF.In 35-44 years old people difference of fluorosis prevalence calculating between DI and TSIF was almost 40%. The most probably reason for this phenomenon was that a person with “questionable” fluorosis wouldn't be calculated as a fluorosis patient. The proportion of “questionable” in 35-44 age group was the highest (40.3%). Conclusion:DI is suitable for large-scale epidemiology survey, and should be combined with community fluorosis index (CFI), while TSIF is suitable for esthetic study, especially for severe fluorosis patients.