Design of the Synergistic Rectifying Interfaces in Mott-Schottky Catalysts.

The functions of interfacial synergy in heterojunction catalysts are diverse and powerful, providing a route to solve many difficulties in energy conversion and organic synthesis. Among heterojunction-based catalysts, the Mott-Schottky catalysts composed of a metal-semiconductor heterojunction with predictable and designable interfacial synergy are rising stars of next-generation catalysts. We review the concept of Mott-Schottky catalysts and discuss their applications in various realms of catalysis. In particular, the design of a Mott-Schottky catalyst provides a feasible strategy to boost energy conversion and chemical synthesis processes, even allowing realization of novel catalytic functions such as enhanced redox activity, Lewis acid-base pairs, and electron donor-acceptor couples for dealing with the current problems in catalysis for energy conversion and storage. This review focuses on the synthesis, assembly, and characterization of Schottky heterojunctions for photocatalysis, electrocatalysis, and organic synthesis. The proposed design principles, including the importance of constructing stable and clean interfaces, tuning work function differences, and preparing exposable interfacial structures for designing electronic interfaces, will provide a reference for the development of all heterojunction-type catalysts, electrodes, energy conversion/storage devices, and even super absorbers, which are currently topics of interest in fields such as electrocatalysis, fuel cells, CO2 reduction, and wastewater treatment.

Analysis of sterilizer allocation and related factors in dental health-care settings in Yunnan Province, China: a cross-sectional study.

OBJECTIVE: To investigate the status and related factors of sterilizers in dental health-care settings in Yunnan Province, with the aim of providing a theoretical basis for the health administrative department to formulate regional quality control programs and systems, proposing reasonable suggestions for optimizing the allocation of sterilizer resources in Yunnan's dental health-care settings, thereby improving resource utilization efficiency. METHODS: This cross-sectional survey was conducted in 2600 dental health-care settings in Yunnan Province in March 2020. Uni-variable linear regression, multi-variable linear regression, curve fitting and threshold effect analysis were used to understand the relationship between dental units and sterilizers. RESULTS: A total of 2600 dental health-care settings were included. The disinfection and sterilization work were mainly completed by the dental department in 1510(58.1%) institutions. 44(1.7%) institutions were not allocated sterilization equipment, and 1632 (62.8%) had only one sterilizer. The median allocation of sterilizers was 1.0. Uni-variable linear regression showed significant differences in covariates such as dental unit, dental handpiece, disinfection equipment, dentist, and dental assistant, which were more sensitive (p < 0.001) and statistically significant. The adjusted model was more stable in the multi-variable linear regression, and the differences in covariates between different settings were statistically significant. Curve fitting revealed an S-shaped curvilinear relationship between the number of dental units and sterilizers in oral healthcare settings. CONCLUSION: The disinfection and sterilization work was mainly completed by the dental department in dental health-care settings in Yunnan Province. Sterilizer allocation increases with the number of dental units, but some institutions have insufficient allocation of sterilizer and manpower resources, resulting in certain risks of infection control. Thus, it is necessary to strengthen supervision, inspection and regional quality control work in infection control of dentistry.

P2X3-P2X7 SNPs and gene-gene and gene-environment interactions on pediatric asthma.

BACKGROUND: To investigate the relationship between polymorphisms of P2X3, P2X7 genes and environment interaction with susceptibility of childhood asthma. METHODS: We conducted a matched case-control study with 170 cases and 175 healthy controls. The rs10896611, rs2276038, rs3781899 in P2X3 and rs1718119, rs3751143 in P2X7 polymorphisms were genotyped using the technique of an improved multiplex ligation detection reaction. Gene-gene, gene-environment and haplotype-environment interactions were tested using the generalized multi-factor dimensionality reduction method. RESULTS: There were no differences between cases and controls in allele or genotype frequencies of P2X3 and P2X7. The C/C, G/C genotypes of rs10896611, and C/C, C/T genotypes of rs2276038 and G/G, G/A genotypes of rs3781899 were associated with asthmatic cough (p > 0.05). The haplotype GCT of P2X3 reduced the risk of asthma (OR = 0.48, p = 0.048), and the haplotypes AGT (OR = 0.45, p = 0.001) and GCC (OR = 2.16, p = 0.002) were associated with asthmatic cough. The haplotype AA of P2X7 increased risk of asthma severity (p < 0.05). The three-locus model indicated a potential haplotype-environment interaction in GCT, ETS, and pet (p = 0.001). CONCLUSIONS: The rs10896611, rs2276038 and rs3781899 of P2X3 minor alleles increased the risk of asthmatic cough. Haplotype GCT of P2X3 was a protective factor for asthma, the haplotype AGT was a protective factor and GCC was a risk factor for asthma with cough. In addition, the interactions of haplotype GCT of P2X3, ETS and pet may increase an individual's susceptibility to asthma.

Boosting Mass Exchange between Pd/NC and MoC/NC Dual Junctions via Electron Exchange for Cascade CO2 Fixation.

Merging existing catalysts together as a cascade catalyst may achieve "one-pot" synthesis of complex but functional molecules by simplifying multistep reactions, which is the blueprint of sustainable chemistry with low pollutant emission and consumption of energy and materials only when the smooth mass exchange between different catalysts is ensured. Effective strategies to facilitate the mass exchange between different active centers, which may dominate the final activity of various cascade catalysts, have not been reached until now, even though charged interfaces due to work function driven electron exchange have been widely observed. Here, we successfully constructed mass (reactants and intermediates) exchange paths between Pd/N-doped carbon and MoC/N-doped carbon induced by interfacial electron exchange to trigger the mild and cascade methylation of amines using CO2 and H2. Theoretical and experimental results have demonstrated that the mass exchange between electron-rich MoC and electron-deficient Pd could prominently improve the production of N,N-dimethyl tertiary amine, which results in a remarkably high turnover frequency value under mild conditions, outperforming the state-of-the-art catalysts in the literature by a factor of 5.9.

Facilitating Hot Electron Injection from Graphene to Semiconductor by Rectifying Contact for Vis-NIR-Driven H2 O2 Production.

Solar-driven production of hydrogen peroxide (H2 O2 ), as an important industrial chemical oxidant with an extensive range of applications, from oxygen reduction is a sustainable alternative to mainstream anthraquinone oxidation and direct hydrogenation of dioxygen methods. The efficiency of solar to hydrogen peroxide over semiconductor-based photocatalysts is still largely limited by the narrow light absorption to visible light. Here, the authors proposed and demonstrate the proof-of-concept application of light-generated hot electrons in a graphene/semiconductor (exemplified with widely used TiO2 ) dyad to largely extend visible light spectra up to 800 nm for efficient H2 O2 production. The well-designed graphene/semiconductor heterojunction has a rectifying interface with a zero barrier for the hot electron injection, largely boosting excited hot electrons with an average lifetime of ≈0.5 ps into charge carriers with a long fluorescent lifetime (4.0 ns) for subsequent H2 O2 production. The optimized dyadic photocatalyst can provide an H2 O2 yield of 0.67 mm g-1  h-1 under visible light irradiation (λ ≥ 400 nm), which is 20 times of the state-of-the-art noble-metal-free titanium oxide-based photocatalyst, and even achieves an H2 O2 yield of 0.14 mm g-1  h-1 upon photoexcitation by near-infrared-region light (≈800 nm).

Tunable Surface Electric Field of Electrocatalysts via Constructing Schottky Heterojunctions for Selective Conversion of Trash Ions to Treasures.

Surface electric field of catalyst is widely recognized as one of the key points to boost catalytic activity. However, there is still a lack of convenient ways to tune the surface electric field to selectively boost the catalytic conversions of different types of reactants in specific catalytic reactions. Here, we introduce a conceptually new method to tune the surface electric field of electrode materials by adjusting the number and density of heterojunctions inside. Both theoretical and experimental results prove that the well-designed surface electric field of an electrocatalyst plays a key role in facilitating pre-adsorption and/or activation of reactants for selective conversion of trash ions to useful products in hydrogen and oxygen evolution reactions as well as NOx - reduction reactions.

Direct Oxygen Transfer from H2 O to Cyclooctene over Electron-Rich RuO2 Nanocrystals for Epoxidation and Hydrogen Evolution.

Production of more than 20 million tons of epoxides per year from olefins suffers from low atom economy due to the use of oxidants and complex catalysts with unsatisfactory selectivity, leading to huge environmental and economic costs. We present a proof-of-concept application of electron-rich RuO2 nanocrystals to boost the highly selective epoxidation of cyclooctene via direct oxygen transfer from water as the sole oxygen source under mild conditions. The enhanced electron enrichment of RuO2 nanocrystals via the Schottky effect with nitrogen-doped carbons largely promotes the capture and activation of cyclooctene to give a high turnover frequency (260 h-1 ) of cyclooctene oxide, far surpassing the reported values (<20 h-1 ) of benchmarked catalysts at room temperature with oxidants. Our electron-rich RuO2 electrocatalysts enable efficient and durable hydrogen production (Faradaic efficiency >90 %) on the cathode without impacting on the selectivity to epoxide (>99 %) on the anode.

[Association of the ADCY9 gene and gene-environmental interaction with the susceptibility to childhood bronchial asthma]. / ADCY9åŸºå› ä¸Žå„¿ç«¥æ”¯æ°”ç®¡å“®å–˜çš„æ˜“æ„Ÿæ€§åŠçŽ¯å¢ƒäº¤äº’ä½œç”¨åˆ†æž.

OBJECTIVES: To study the association of the single nucleotide polymorphisms (SNPs) of the adenylyl cyclase IX (ADCY9) gene at rs1967309, rs2230739, rs2601814, rs2601825, rs2601796, and rs2283497 loci and gene-environment interaction with childhood bronchial asthma (asthma for short). METHODS: A total of 123 children with asthma who attended the hospital from March 2019 to September 2021 were enrolled as the asthma group, among whom 84 (68.3%) had mild-to-moderate attacks and 39 (31.7%) had severe attacks. A total of 124 healthy children were enrolled as the control group. The association of the SNPs and haplotypes of the ADCY9 gene at the above 6 loci with the susceptibility to childhood asthma was evaluated. The method of generalized multifactor dimensionality reduction was used to analyze gene-environment interaction. RESULTS: Polymorphisms were observed for the ADCY9 gene at the above six loci in both the asthma and control groups, and there were significant differences in genotype and allele frequencies at the rs1967309 locus between the two groups (P<0.05). There was no significant difference in the distribution frequency of haplotypes TA and GG between the asthma and control groups (P>0.05). The generalized multifactor dimensionality reduction analysis showed interaction between rs1967309 locus and allergen contact (P<0.05), which increased the risk of asthma (OR=1.585, P<0.05). CONCLUSIONS: The rs1967309 locus of the ADCY9 gene is associated with the susceptibility to childhood asthma, and the locus and allergen contact have a synergistic effect on the development of asthma.

Oxygen Vacancy Engineering of Titania-Induced by Sr2+ Dopants for Visible-Light-Driven Hydrogen Evolution.

A Sr2+-doping strategy is developed to engineer rich oxygen vacancies in porous titania for boosting visible-light-driven photocatalytic activity. The incorporation of strontium, with a larger atom radius than titanium, leads to the release of a lattice oxygen atom in the titania, causing the generation of an oxygen vacancy. The optimal Sr2+-doped titania sample with rich oxygen vacancies achieves a photocatalytic hydrogen production rate as high as 1092 µmol h-1 g-1, which is 4 and 16 times higher than the unmodified titania with less oxygen vacancies and the bench-marked P25, respectively.

Oral health status of 12-year-old children in Lisu minority ethnic group in China: a cross-sectional study.

BACKGROUND: Lisu is an ethnic minority group and most of them are living in Yunnan, China. This study investigated the oral health status among 12-year-old Lisu children in Yunnan. METHOD: This survey employed a multistage sampling method to recruit 12-year-old Lisu children. Two calibrated dentists performed the oral examinations in the primary schools. They examined dental caries, gingival bleeding and dental fluorosis using the diagnosis criteria recommended by the World Health Organization. A self-administrated questionnaire was distributed to the children to collect their sociodemographic background information and oral health-related behaviours. A chi-square test, the Mann-Whitney U test, zero-inflated negative binomial (ZINB) regression and multivariate logistic regression were used for statistical analysis. RESULTS: This survey invited 512 children, and 482 children (48% boys) participated in the study (response rate: 94%). Their caries prevalence was 35% and their caries experience in mean (SD) DMFT scores was 0.63 (0.10). The mean (SD) DT score was 0.60 (1.10), consisting 95% of the mean DMFT scores. No dental fluorosis was observed; whereas 426 children (88%) had gingival bleeding. Results of ZINB model indicated sex and sugary-snacking habits were related to the dental caries experience (p < 0.05). The gingival-bleeding prevalence was associated with the mother's education level, the child's monthly-pocket money and daily toothbrushing frequency (p < 0.05). CONCLUSION: Dental caries and gingival bleeding were prevalent among 12-year-old Lisu children in the Yunnan province in China, and most of the decayed teeth were unrestored. Dental fluorosis was not observed in the children.

Schottky Barrier-Induced Surface Electric Field Boosts Universal Reduction of NOx - in Water to Ammonia.

NOx - reduction acts a pivotal part in sustaining globally balanced nitrogen cycle and restoring ecological environment, ammonia (NH3 ) is an excellent energy carrier and the most valuable product among all the products of NOx - reduction reaction, the selectivity of which is far from satisfaction due to the intrinsic complexity of multiple-electron NOx - -to-NH3 process. Here, we utilize the Schottky barrier-induced surface electric field, by the construction of high density of electron-deficient Ni nanoparticles inside nitrogen-rich carbons, to facilitate the enrichment and fixation of all NOx - anions on the electrode surface, including NO3 - and NO2 - , and thus ensure the final selectivity to NH3 . Both theoretical and experimental results demonstrate that NOx - anions were continuously captured by the electrode with largely enhanced surface electric field, providing excellent Faradaic efficiency of 99 % from both electrocatalytic NO3 - and NO2 - reduction. Remarkably, the NH3 yield rate could reach the maximum of 25.1 mg h-1 cm-2 in electrocatalytic NO2 - reduction reaction, outperforming the maximum in the literature by a factor of 6.3 in neutral solution. With the universality of our electrocatalyst, all sorts of available electrolytes containing NOx - pollutants, including seawater or wastewater, could be directly used for ammonia production in potential through sustainable electrochemical technology.

Heterojunction-Based Electron Donators to Stabilize and Activate Ultrafine Pt Nanoparticles for Efficient Hydrogen Atom Dissociation and Gas Evolution.

Platinum (Pt) is the most effective bench-marked catalyst for producing renewable and clean hydrogen energy by electrochemical water splitting. There is demand for high HER catalytic activity to achieve efficient utilization and minimize the loading of Pt in catalysts. In this work, we significantly boost the HER mass activity of Pt nanoparticles in Ptx /Co to 8.3 times higher than that of commercial Pt/C by using Co/NC heterojunctions as a heterogeneous version of electron donors. The highly coupled interfaces between Co/NC and Pt metal enrich the electron density of Pt nanoparticles to facilitate the adsorption of H+ , the dissociation of Pt-H bonds and H2 release, giving the lowest HER overpotential of 6.9 mV vs. RHE at 10 mA cm-2 in acid among reported HER electrocatalysts. Given the easy scale-up synthesis due to the stabilization of ultrafine Pt nanoparticles by Co/NC solid ligands, Ptx /Co can even be a promising substitute for commercial Pt/C for practical applications.

Electrochemical Reduction of N2 into NH3 by Donor-Acceptor Couples of Ni and Au Nanoparticles with a 67.8% Faradaic Efficiency.

The traditional NH3 production method (Haber-Bosch process) is currently complemented by electrochemical synthesis at ambient conditions, but the rather low selectivity (as indicated by the Faradaic efficiency) for the electrochemical reduction of molecular N2 into NH3 impedes the progress. Here, we present a powerful method to significantly boost the Faradaic efficiency of Au electrocatalysts to 67.8% for the nitrogen reduction reaction (NRR) by increasing their electron density through the construction of inorganic donor-acceptor couples of Ni and Au nanoparticles. The unique role of the electron-rich Au centers in facilitating the fixation and activation of N2 was also investigated via theoretical simulation methods and then confirmed by experimental results. The highly coupled Au and Ni nanoparticles supported on nitrogen-doped carbon are stable for reuse and long-term performance of the NRR, making the electrochemical process more sustainable for practical application.

Tooth wear among five-year-old children in Jakarta, Indonesia.

BACKGROUND: This study aimed to evaluate the prevalence of tooth wear among preschool children in Jakarta, Indonesia, and examine the risk factors associated with its occurrence. METHODS: An epidemiological survey was conducted with a cross-sectional study design. The participants were recruited via cluster sampling. Tooth wear was clinically assessed by one examiner using the Basic Erosive Wear Examination (BEWE) criteria. The children's caries experience was also recorded. The parents of the participating children completed a self-administered questionnaire to answer demographic questions about the children and gather information about the children's diet and oral health behaviors as well as the parents' dental health-related knowledge. The data were analyzed using the Chi-square test and binary logistic regression. RESULTS: A total of 752 five-year-old children were invited to participate, with 691 (92%) enrolling in the study. Tooth wear occurred in 23% (161/691, BEWE > 0) of the participants, in which 78% (125/161) had at least one moderate tooth wear status (BEWE = 2). The consumption of citrus drinks, fruit juice, and vitamin C supplement drinks, together with the child's caries experience, the father's education level, and the family's socioeconomic status, were significantly associated with tooth wear. CONCLUSIONS: The five-year-old preschool children in Jakarta had a relatively low prevalence of tooth wear. Those consuming more acidic drinks, those with a higher socioeconomic status, and those with an absence of caries experience had a higher risk of tooth wear.

Dental caries status of Lisu preschool children in Yunnan Province, China: a cross-sectional study.

BACKGROUND: Dental caries is still considered a major public health concern for human beings, especially minority groups and those living in disadvantaged communities. The Lisu is a minority group in China of more than 702,000 people located primarily in Yunnan Province. The present study was aimed at studying the status of dental caries status, as well as its risk factors, among Lisu children aged 5 years in Yunnan Province, China. METHODS: A multistage cluster sampling method was employed for participants' recruitment. Two calibrated dentists carried out the clinical examination with dental mirrors and CPI probes under an LED headlight. The dental caries experience was assessed by the dmft index. Oral hygiene status was evaluated using the visible plaque index (VPI). Information on the child's socio-demographic characteristics and oral health-related practices were collected using a parental questionnaire. A zero-inflated negative binomial regression (ZINB) was employed to analyse the associations between the dental caries status and the children's social-demographic status and their oral health-related behaviours. RESULTS: In all, 470 Lisu children aged 5 were invited, and 404 were examined. Their mean dmft (±SD) and caries prevalence were 5.6 ± 4.8 and 80%, respectively. Their mean VPI scores were 58% ± 21%. Lisu children who brushed their teeth at least once daily had higher dmft scores, and children from high-income families were more likely to have dental caries. CONCLUSION: The prevalence of dental caries among Lisu children aged 5 years in Yunnan, China was high, and their caries status was severe, with a majority of carious teeth untreated. The dental caries experience of Lisu children aged 5 was related to their brushing frequency and families' economic backgrounds.

Attitude toward and awareness of medical-dental collaboration among medical and dental students in a university in Indonesia.

BACKGROUND: Medical-dental collaboration expands patients' access to health services, improves healthcare outcomes, and reduces the burden and cost of care, especially for those with chronic diseases. The aim of the present study is to investigate the attitude toward and awareness of medical-dental collaboration among medical and dental students attending the Universitas Indonesia. METHODS: All medical and dental students at the Universitas Indonesia were invited to participate in a web-based questionnaire survey that contained eight questions on attitudes toward medical-dental collaboration and two questions regarding awareness of dental-medical collaborative practices. The demographic backgrounds of all participants were obtained. The chi-square test and logistic regression analysis were employed for data analysis. RESULTS: A total of 1,432 questionnaires were distributed, and 1,137 (79%) were appropriately completed. In general, 992 (87%) students had a positive attitude toward medical-dental collaboration. Dental students had a more positive attitude than medical students (odds ratio [OR] = 2.694; p = 0.001), and senior students had a more positive attitude than junior students (OR = 2.271; p = 0.001). Most students (86%) were aware of medical-dental collaboration at the Universitas Indonesia and reported that emergency medicine, surgery, and otolaryngology were the three most common medical disciplines that entailed medical-dental collaboration. CONCLUSIONS: In general, the medical and dental students demonstrated positive attitudes and awareness of medical-dental collaboration at the Universitas Indonesia. Positive attitude and awareness can establish an essential foundation for fostering collaboration between medicine and dentistry, which is vital to improve resource efficiency and healthcare standards.

Clinical studies on core-carrier obturation: a systematic review and meta-analysis.

BACKGROUND: This systematic review aimed to evaluate the clinical performance of core-carrier obturation in endodontic treatment. METHODS: Keywords of "(core carrier OR Thermafil) OR (cold lateral condensation OR lateral condensation) OR (warm vertical condensation OR vertical condensation) AND (obturation OR root canal filling) AND clinical study" were searched for all obtainable publications up to year 2017 in the databases of PubMed, ScienceDirect, EMBASE, Scopus and Web of Science. The success rate, short-term postoperative pain, overfilling and adaptation of core-carrier obturation from clinical studies were selected. Reviews, laboratory studies, animal studies and irrelevant reports were excluded. RESULTS: 1349 relevant articles were identified with 149 duplicated articles removed and 1173 irrelevant articles were excluded after screening. The titles and abstracts of the 19 identified articles were screened in the systematic review. The full texts of remaining articles were retrieved with data extracted for meta-analysis on the success rate, postoperative pain, overfilling and adaptation of obturation. The pooled success rate of core-carrier obturation was 83% (95% CI: 69%-91%). The pooled incidence of 1-day and 7-day short-term postoperative pain were 35% (95% CI: 15%-62%) and 6% (95% CI: 1-35%). The pooled proportion of teeth with overfilling and adequate adaptation of the obturation material were 31% (95% CI: 18%-50%) and 85% (95% CI: 75%-91%), respectively. CONCLUSIONS: The success rate of endodontic treatment using core-carrier obturation was 83%. Short-term postoperative pain was not uncommon (24%). Most teeth (85%) had adequate adaptation using core-carrier obturation material, but a considerable amount of teeth (31%) had overfilling.

Caries remineralisation and arresting effect in children by professionally applied fluoride treatment - a systematic review.

BACKGROUND: As a low-cost and easily operated treatment, the use of professionally applied topical fluoride was approved for preventing dental caries and remineralising early enamel caries or white spot lesions. It is also used to arrest dentine caries. The aim of this study is to investigate the clinical efficacy of professional fluoride therapy in remineralising and arresting caries in children. METHOD: A systematic search of publications from 1948 to 2014 was conducted using four databases: PubMed, Cochrane Library, ISI Web of Science and Embase. The key words used were (fluoride) AND (remineralisation OR remineralization OR arresting) AND (children caries OR early childhood caries). The title and abstract of initially identified publications were screened. Clinical trials about home-use fluorides, laboratory studies, case reports, reviews, non-English articles and irrelevant studies were excluded. The full texts of the remaining papers were retrieved. Manual screening was conducted on the bibliographies of the remaining papers to identify relevant articles. RESULTS: A total of 2177 papers were found, and 17 randomised clinical trials were included in this review. Ten studies investigated the remineralising effect on early enamel caries using silicon tetrafluoride, fluoride gel, silver diamine fluoride or sodium fluoride. Seven studies reported an arresting effect on dentine caries using silver diamine fluoride or nano-silver fluoride. Meta-analysis was performed on four papers using 5 % sodium fluoride varnish to remineralise early enamel caries, and the overall percentage of remineralised enamel caries was 63.6 % (95 % CI: 36.0 % - 91.2 %; p < 0.001). Meta-analysis was also performed on five papers using 38 % silver diamine fluoride to arrest dentine caries and the overall proportion of arrested dentine caries was 65.9 % (95 % CI: 41.2 % - 90.7 %; p < 0.001). CONCLUSION: Professionally applied 5 % sodium fluoride varnish can remineralise early enamel caries and 38 % silver diamine fluoride is effective in arresting dentine caries.

Attitude and awareness of medical and dental students towards collaboration between medical and dental practice in Hong Kong.

BACKGROUND: Medical-dental collaboration is essential for improving resource efficiency and standards of care. However, few studies have been conducted on it. This study aimed to investigate the attitude and awareness of medical and dental students about collaboration between medical and dental practices in Hong Kong. METHODS: All medical and dental students in Hong Kong were invited to complete a questionnaire survey at their universities, hospitals and residential halls. It contained 8 questions designed to elicit their attitudes about the collaboration between medical and dental practice. Students were also asked about their awareness of the collaboration between dentistry and medicine. The questionnaires were directly distributed to medical and dental students. The finished questionnaires were immediately collected by research assistants on site. RESULTS: A total of 1,857 questionnaires were distributed and 809 (44%) were returned. Their mean attitude score (SD) towards medical-dental collaboration was 6.37 (1.44). Most students (77%) were aware of the collaboration between medical and dental practice in Hong Kong. They considered that Ear, Nose & Throat, General Surgery and Family Medicine were the 3 most common medical disciplines which entailed collaboration between medical and dental practice. CONCLUSION: In this study, the medical and dental students in general demonstrated a good attitude and awareness of the collaboration between medical and dental practice in Hong Kong. This established an essential foundation for fostering medical-dental collaboration, which is vital to improving resource efficiency and standards of care.

Dental and periodontal status of 12-year-old Dai school children in Yunnan Province, China: a cross-sectional study.

BACKGROUND: The Dai people are one of the ethnic minorities in China and have a population of 1,260,000. They have the same origin as one of the main ethnic groups in Laos and Thailand. The study aims to describe the dental caries and gingival status of 12-year-old Dai children in China and to study the factors affecting their oral-health status. METHODS: This cross-sectional oral-health survey was conducted from 2011-2012 with ethics approval. A sample of 12-year-old Dai children living in Yunnan, China, was selected using a multistage and cluster sampling method. One trained examiner performed the clinical examination. Caries experience was measured using DMFT index, and gingival status was assessed with CPI index. A self-completed questionnaire was sent to the children, and they were asked about their backgrounds and oral-health-related behaviors and oral-health knowledge. Binary logistic regression analysis was performed to investigate the factors that affected the caries status. RESULTS: A total of 875 children were invited, and 823 (94 %) joined the survey. The prevalence of caries experience among the participants was 40 %. The mean DMFT and DT scores were 0.9 and 0.8, respectively. Most children (93 %) had gingivitis, and many (46 %) had calculus. Girls and those who had visited a dentist during the previous year had a higher prevalence of caries. CONCLUSION: Dental caries were prevalent among 12-year-old Dai children in China. The periodontal condition of most of the children was poor. Caries were associated with gender and dental attendance.