A microscopic study of the proton-neutron symmetry and phonon structure of the low-lying states in 92Zr

We studied in a microscopic multiphonon approach the proton-neutron symmetry and phonon structure of some low-lying states recently discovered in 92Zr. We confirm the breaking of F-spin symmetry, but argue that the breaking mechanism is more complex than the one suggested in the original shell model analysis of the data. We found other new intriguing features of the spectrum, like a pronounced multiphonon fragmentation of the states and a tentative evidence of a three-phonon mixed symmetry state.Comment: 13 pages, to appear in Phys. Rev.

Patients' satisfaction with dental services provided by an university in Hong Kong

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Oral health status and behaviours of preschool children in Hong Kong.

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Outcome of endodontic therapy with thermafil and lateral condensation technique

Journal of Dental Research, 2003, v. 82 Spec. Iss. C, p. C-635, abstract no. 19published_or_final_versio

Effectiveness of silver diamine fluoride and sodium fluoride varnish in arresting dentin caries in Chinese pre-school children

Untreated dental caries in Chinese pre-school children is common. This prospective controlled clinical trial investigated the effectiveness of topical fluoride applications in arresting dentin caries. Three hundred seventy-five children, aged 3-5 years, with carious upper anterior teeth were divided into five groups. Children in the first and second groups received annual applications of silver diamine fluoride solution (44,800 ppm F). Sodium fluoride varnish (22,600 ppm F) was applied every three months to the lesions of children in the third and fourth groups. For children in the first and third groups, soft carious tissues were removed prior to fluoride application. The fifth group was the control. Three hundred eight children were followed for 30 months. The respective mean numbers of arrested carious tooth surfaces in the five groups were 2.5, 2.8, 1.5, 1.5, and 1.3 (p < 0.001). Silver diamine fluoride was found to be effective in arresting dentin caries in primary anterior teeth in pre-school children.published_or_final_versio

Occlusal Features and Caries Experience of Hong Kong Chinese Preschool Children: A Cross-Sectional Study

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Effect of fee-paying systems on consumption of dental services

Session 18 - Health Services Research: Utilization: abstract no. 00108published_or_final_versio

Clinical diagnosis of fissure caries with conventional and laser-induced fluorescence techniques

We studied the in vivo validity of dentinal fissure caries diagnosis by visual examination, bitewing radiography, and use of a laser-induced fluorescence device (DIAGNOdent). A total of 144 and second molars with macroscopically intact occlusal surfaces in 41 Chinese young adults were examined visually, by bitewing radiography, and by DIAGNOdent. Visual examination after pit and fissure opening was used as the reference standard. The sensitivity and specificity of detecting caries that had extended into the dentin were, respectively, 0.89 and 0.44 by visual detection of opacity or discoloration after air drying, 0.13 and 1.00 by bitewing radiography to detect radiolucency extending into the dentin, and 0.70 and 0.84 by DIAGNOdent testing with a cut-off score of 40. Caries detection by a combination of visual examination and DIAGNOdent had a sensitivity of 0.67 and specificity of 0.94. Receiver operating characteristic analysis showed that this combined approach was superior to the other methods. © Springer-Verlag London Limited 2009.published_or_final_versionSpringer Open Choice, 01 Dec 201

Use of professionally administered topical fluorides in Asia

Professionally applied topical fluoride varnish, gel, and solution have been shown to be effective in preventing and in arresting dental caries. Their use in different countries in Asia varies greatly and may not correlate with the dental caries situation of the populations in the countries. In the higher-income countries, use of fluoride varnish and gel is common among dental professionals. In contrast, the use of professionally administered topical fluorides is not common in the lower-income countries. Fluoride varnish, being easy to apply and safe, has been the preferred agent for the prevention of early childhood caries, which is prevalent in many developing countries in Asia. The relatively high cost of professionally administered fluoride agents and the shortage of a dental workforce, especially in lower income countries, have hampered the widespread adoption of these effective caries prevention methods in the private and public dental services. Government health policies should be pursued to lower the cost of treatment, either through incentives for local production and/or elimination of taxes and tariffs on imported fluoride products.published_or_final_versio

Caries assessment by clinical examination with or without radiographs of young Chinese adults

Objective: To compare caries status assessment of posterior teeth of young Chinese adults by using clinical examination alone and with the supplemental use of bitewing radiographs. Methods: Two calibrated dentists examined the posterior teeth of 200 Chinese university students (aged 18-24 years) using dental mirrors and probes under optimal lighting. Caries was diagnosed by visual detection of carious cavities. Duplicate examinations were performed to monitor intra- and inter-examiner variations. Bitewing radiographs were taken and examined by an independent dentist. Caries was recorded when a lesion extended into dentine. Results: Among the 3,162 posterior teeth examined, 113 were detected with caries. More than one third (35.4%) of the caries found in the posterior teeth was not detected from reading the radiographs but was detected by clinical examination. About half (51.4%) of the caries was found on the bitewing radiographs only, leaving 13.2% being detected by using either method. With the supplement of bitewing radiographs, there was a 105% increase in the number of carious lesions detected. This leads to a correction factor of 1.13 for adjustment of the mean DMFT score obtained from conducting clinical examinations alone. Conclusion: Due to the significant number of clinically undetected carious cavities in these young Chinese adults who live in a community with water fluoridation, it may be advisable to use a correction factor to adjust the caries experience obtained from epidemiological surveys when bitewing radiographs are not available. © 2008 FDI/World Dental Press.link_to_subscribed_fulltex