Outreach dental care programme for older adults using long-term care services in Hong Kong: A qualitative study.

OBJECTIVES: To explore the effects and improvement needs of an outreach dental care programme (ODCP) for older adults using residential care or daycare services from the perspectives of the caregivers, the dentists and administrative staff involved in the implementation of the ODCP. METHODS: A qualitative study was conducted through semi-structured interviews with three stakeholders, long-term care (LTC) facility caregivers, administrative staff and dentists working for the ODCP. Combined maximum variation and snowball sampling strategies were adopted, and 22, 9 and 7 participants were interviewed from each stakeholder, respectively. The interviews were conducted via telephone, which were audio-recorded and transcribed verbatim for analysis. NVivo software was used for storing and analysing the data. Data analysis was conducted continuously during the study. RESULTS: Most participants opined that the ODCP benefited older adults by raising their oral health conditions and awareness. However, they complained of the complicated administrative procedures, unmet dental treatment needs, inefficient coordination, unclear work guidelines and shortage of dental manpower. More advanced dental treatment options, better coordination among different parties, simpler administrative processes and better incentives for dentists were proposed to further improve the programme. CONCLUSIONS: According to the stakeholders, ODCP seems beneficial to older adults using LTC services. Further improvements in the scope of dental treatments, cooperation between the outreach dental teams and caregivers, and streamlining of the administrative process are needed for the provision of effective outreach dental care to satisfy the unmet treatment needs of older adults who use LTC services. Better incentives are needed to attract and retain dentists.

Is Mutans Streptococci count a risk predictor of Early Childhood Caries? A systematic review and meta-analysis.

BACKGROUND: The review aims to determine the risk predictability of mutans streptococci in the development of carious lesions in children with primary dentition. METHODS: Longitudinal observational studies with at least 6 months follow-up and evaluating mutans streptococci presence in caries-free children under 6 years of age for the development of any cavitated or non-cavitated carious lesion. Six databases and grey literature were searched without any restrictions. Risk of bias was evaluated using the New Castle Ottawa scale for longitudinal studies, and the certainty of the evidence was evaluated by Grading of Recommendations Assessment, Development and Evaluation using GRADEpro software. Meta-analysis was performed using a random effect (DerSimonian and Laird, DL) model, and heterogeneity was evaluated using tau-squared, I2 statistics and prediction interval. Sensitivity analysis was performed to assess the relationship between the mutans streptococci presence at baseline and the caries development, according to the sample and methods used for the microbiological assessment and the length of follow-up of the studies. Publication bias was checked by funnel plot using a random effect (DerSimonian and Laird, DL) model. RESULTS: Twelve studies met the inclusion criteria and were included in the review. Four studies received a maximum of 9 stars, and among the remaining eight studies, six received 8 stars and the rest two studies were assigned 7 stars in the risk of bias scale. After pooling the results quantitatively, odds ratio (OR) was found to be 4.13 (95% CI: 3.33, 5.12), suggesting that children with mutans streptococci had 4 times higher odds of developing caries later (p < 0.001). Four studies were pooled to compare future caries experience among children with and without mutans streptococci at baseline, obtaining standardized mean difference (SMD) of 0.85 (95% CI: 0.33, 1.37), indicating a large effect (p < 0.001). Certainty of evidence was found to be moderate, and no publication bias was reported by the funnel plot criteria of symmetry. CONCLUSIONS: Presence of mutans streptococci in a preschool child is a risk predictor for future caries experience. Early identification of children with increased caries-risk may facilitate in implementation of appropriate preventive strategies.

Motivational interviewing for caries prevention in adolescents: a randomized controlled trial.

OBJECTIVE: The objective of this study is to investigate the effectiveness of motivational interviewing (MI) in changing health behaviors (snack and toothbrushing) and preventing dental caries among adolescents. METHODS: Five hundred and twelve adolescents with unfavorable caries-related behaviors ("snacking three times or more a day" and/or "toothbrushing less often than twice a day") were randomly assigned to three groups. Group I received prevailing health education (oral health talks and pamphlets). Participants in group II joined a one-on-one face-to-face MI session. In group III, a patient communication tool (Cariogram) was incorporated to facilitate the MI process. At baseline and 24 months post-intervention, a self-administered questionnaire gathered information of participants' sociodemographic characteristics and oral health self-efficacy and behaviors. Their oral hygiene and tooth status were assessed by a blinded examiner. RESULTS: After 24 months, 460 (89.8%) participants were followed up. Compared with group I, (i) restriction of frequent snacking was more likely in group II [OR (95% CI): 3.91 (1.48-10.33)] and group III [OR (95% CI): 6.33 (2.46-16.27)], whereas group III tended to adopt the behavior of toothbrushing twice a day [OR (95% CI): 4.80 (1.79-12.85)]; (ii) no significant between-group difference in plaque score reduction was found (p > 0.05); and (iii) groups II and III developed fewer cavitated teeth (△DICDASII 3-6MFT) [ß (95% CI): - 0.19 (- 0.37, - 0.01) and - 0.20 (- 0.38, - 0.02), respectively], whereas increment of total carious lesions (△DICDASII 1-6MFT) was lower in group III [ß (95% CI): - 0.63 (- 1.24, - 0.02)]. CONCLUSION: MI outperformed prevailing health education in improving oral health behaviors and preventing dental caries among adolescents. CLINICAL RELEVANCE: Incorporating MI into dental care for caries-prone adolescents contributes to optimal health outcomes. TRIAL REGISTRATION: HKUCTR-1852 ( http://www.hkuctr.com/ ) (Hong Kong, 2013).

RISK PREDICTORS OF EARLY CHILDHOOD CARIES INCREMENT-A SYSTEMATIC REVIEW AND META-ANALYSIS.

This systematic review aimed to investigate the risk predictors of caries in primary teeth and evaluate their association with the increment of Early Childhood Caries (ECC) among preschool children. This systematic review included only cohort or case-control studies of at least 2 years duration, over 300 participants and with English full-text. Potentially eligible studies were retrieved from 4 electronic databases (Ovid Embase, Ovid MEDLINE; PubMed, Web of Science) from inception to March 1, 2021. Independent screening and data extraction by 2 reviewers to identify factors associated with ECC increment, including family and socioeconomic factors, dietary and oral health-related habits, and clinical parameters. A total of 18 studies from 163 potential reports were included, involving 1,159,226 preschool children. Lower parental education attainment was found associated with ECC increment (WMD:0.87; 95% CI 0.52, 1.21); whereas immigration status (WMD:-0.38; 95% CI -1.09, 0.34), gender (WMD:-0.02; 95% CI -0.28, 0.24), and dental service utilization (WMD:0.35; 95% CI -0.10, 0.79) were not significant factors for ECC increment. All included studies consistently suggested positive correlations between ECC increment and baseline caries experience, plaque level, cariogenic microorganisms, and prenatal and passive smoking, while mixed findings were detected between ECC increment with dietary and oral hygiene practices. Preschool children whose parents have low education level are more likely to have greater increment of ECC over 2 years. Existing caries lesions, increased dental plaque level, cariogenic microorganisms, prenatal or passive smoking were also consistently identified as risk factors for ECC in all reviewed studies. This systematic review highlights specific risk factors to target for the prevention of ECC and supports implementing more oral health promotion for preschool children with parents of lower educational attainment.

Using next-generation sequencing to detect oral microbiome change following periodontal interventions: A systematic review.

OBJECTIVES: This systematic review was to evaluate the change of oral microbiome based on next-generation sequencing (NGS)-metagenomic analysis following periodontal interventions among systematically healthy subjects. MATERIALS AND METHODS: A structured search strategy consisting of "metagenomics" and "oral diseases" was applied to PubMed, EMBASE, and Web of Science to identify effective papers. The included studies were original studies published in English, using metagenomic approach to analyze the effectiveness of periodontal intervention on oral microbiome among systematically healthy human subjects with periodontitis. RESULTS: A total of 12 papers were included in this review. Due to the heterogeneity of selected study, quantitative analysis was not performed. The findings as to how alpha diversity changed after interventions were not consistent across studies. Six studies illustrated clear separation of microbial composition between dental plaque samples collected before and after intervention using principal coordinates/component analysis. The most commonly detected genera before intervention were Porphyromonas, Treponema, Tannerella, and Prevotella, while Streptococcus and Actinomyces usually increased and became the dominant genera after intervention. Correlation network analysis revealed that after intervention, the topology of network was different compared to the corresponding pre-interventional samples. CONCLUSION: Existing evidence of metagenomic studies depicts a complex change in oral microbiome after periodontal intervention.

Enhanced Fluoride Bioavailability with Incorporation of Arginine in Child Dentifrices.

OBJECTIVE(S): To: 1) examine the fluoride concentrations in commercial child formula dentifrices (CFD)s; and 2) investigate the effect of arginine incorporation in CFDs on fluoride bioavailability. STUDY DESIGN: Five commercial CFDs were examined for fluoride concentrations. Total, total soluble, and insoluble fluorides in CFDs were determined by the modified Taves acid-diffusion method (TAD). Ionic F and MFP were estimated by modified direct method with standard addition technique. L-arginine (L-Arg)/L-arginine monohydrochloride (L-Arg.HCl) were incorporated at 2% w/w in the commercial CFDs. The pH of the toothpaste slurries, buffer capacity of the added Arg, potentially available fluorides (PAF) and 1-min PAF by TAD were determined. RESULTS: The CFDs had 4 to 32% of insoluble fluorides. Addition of L-Arg/L-Arg.HCl significantly improved the fluoride bioavailability in CFDs (p<0.05). Incorporation of L-Arg significantly increased the pH of toothpaste slurries (p<0.05); while L-Arg.HCl decreased the pH. Principal component analysis showed that L-Arg.HCl decreased the pH of toothpaste slurries due to the presence of Cl in the form of HCl; whereas the inherent elements/molecules (Na/P/Pi/F) remain distinct with unidentified influence on the variables. CONCLUSION(S): The CFDs containing NaF only have higher concentrations of bioavailable fluoride. Incorporating arginine (L-arginine or L-arginine monohydrochloride) at 2% w/w improves fluoride bioavailability of the child formula dentifrices.

Effect of oral hygiene programmes on oral opportunistic pathogens during stroke rehabilitation.

OBJECTIVES: This study was to assess the effectiveness of a conventional oral hygiene care programme (COHCP) and an advanced oral hygiene care programme (AOHCP) on prevalence and viable counts of oral opportunistic pathogens among patients undergoing stroke rehabilitation. METHODS: A total of 94 patients were randomized to two groups. Subjects were block randomized to either (a) COHCP: manual toothbrushing with oral hygiene instruction (OHI); or (b) AOHCP: powered toothbrushing, mouthrinsing with chlorhexidine and OHI. Prevalence and viable counts of oral opportunistic pathogens including yeasts, aerobic and facultative anaerobic gram-negative bacilli, Staphylococcus aureus, were assessed at baseline, the end of 3 and 6 months. RESULTS: No significant difference was observed in the prevalence of oral opportunistic pathogens within each group over the clinical trial period. A significant decrease in the viable counts of S. aureus was found over the clinical trial period within AOHCP group (p < 0.05), while the viable counts of yeasts and anaerobic gram-negative bacillus (AGNB) remained stable within each group. Regression analysis failed to detect an association between intervention and the prevalence/viable counts of oral opportunistic pathogens. CONCLUSIONS: Neither oral healthcare programme significantly affects AGNB, yeast or S. aureus over the study period in terms of prevalence and viable counts.

Developmental regulation of lifelong dental experiences and beliefs in Guangzhou and Hong Kong.

AIMS: The aim of this study was to explain through the life-course and life-span perspectives of developmental regulation theory the controls on dental experiences and beliefs throughout the lives of older people in Guangzhou and Hong Kong. BACKGROUND: Dental diseases and disabilities among older people are serious public health concerns in China. METHODS: A facilitator conducted eight focus groups, three in Hong Kong and five in Guangzhou, involving a total of 51 participants. She encouraged discussions about lifetime events to explain dental experiences and beliefs. Transcripts were coded and analysed using a constant comparative approach to identify themes that explained the regulators of dental experiences throughout the participants' lives. RESULTS: Participants explained the influence of culture and history through critical events, and how external and internal factors regulated their current oral health status and beliefs. They emphasised the role of Traditional Chinese Medicine and family, and the stress of social upheaval compounded by a scarcity of dental services. They revealed also how current choice of dental services and health promotional programs, helped by personal food choice, self-reliance, and scepticism, helped them to adjust and cope with dental diseases and disabilities and the commercialisation of dental services. CONCLUSIONS: Dental experiences and beliefs of older people living in Guangzhou and Hong Kong were regulated strongly during personal development by culture and history during critical events, and by various controlling factors, such as health promotion and choice of services supplemented by food choice, nutritional balance, self-reliance, scepticism and social adjustments.

A META-EPIDEMIOLOGICAL REVIEW OF META-ANALYSIS ON ANTI-CARIES EFFECT OF ARGININE-CONTAINING FORMULATIONS.

BACKGROUND: Several significant issues on clinical trials reporting the effect of arginine-containing dental products have been addressed in systematic reviews and meta-analyses identifying the need for high-quality randomized clinical trials. A further methodological analysis of the given systematic reviews with meta-analysis on arginine products might provide information for future high-quality randomized clinical trials and current clinical practice. OBJECTIVE(S): The objective was to perform a meta-epidemiological assessment of meta-analyses reporting the anticaries effect of arginine-containing formulations. METHODS: The data on risk-of-bias assessment, effect size measure, dispersion of estimated precision, and follow-up period were summarized for the meta-epidemiological review analysis. RESULTS: Studies with larger magnitude of effect sizes might present with unclear random sequence generation and unclear allocation concealment representing the selection bias. There was a significant strong negative correlation between the follow-up time and dispersion of precision estimates (rs = -0.79, P = .034). CONCLUSION: Results show that clinical trials on arginine dental products have methodological shortcomings. Both the selection bias and follow-up period influence the effect size magnitude and subsequent precision dispersion during evidence synthesis in clinical trials on arginine-containing dental products.

Salivary Microbiome Diversity in Caries-Free and Caries-Affected Children.

Dental caries (tooth decay) is an infectious disease. Its etiology is not fully understood from the microbiological perspective. This study characterizes the diversity of microbial flora in the saliva of children with and without dental caries. Children (3-4 years old) with caries (n = 20) and without caries (n = 20) were recruited. Unstimulated saliva (2 mL) was collected from each child and the total microbial genomic DNA was extracted. DNA amplicons of the V3-V4 hypervariable region of the bacterial 16S rRNA gene were generated and subjected to Illumina Miseq sequencing. A total of 17 phyla, 26 classes, 40 orders, 80 families, 151 genera, and 310 bacterial species were represented in the saliva samples. There was no significant difference in the microbiome diversity between caries-affected and caries-free children (p > 0.05). The relative abundance of several species (Rothia dentocariosa, Actinomyces graevenitzii, Veillonella sp. oral taxon 780, Prevotella salivae, and Streptococcus mutans) was higher in the caries-affected group than in the caries-free group (p < 0.05). Fusobacterium periodonticum and Leptotrichia sp. oral clone FP036 were more abundant in caries-free children than in caries-affected children (p < 0.05). The salivary microbiome profiles of caries-free and caries-affected children were similar. Salivary counts of certain bacteria such as R. dentocariosa and F. periodonticum may be useful for screening/assessing children's risk of developing caries.

Effectiveness of DIAGNOdent in Detecting Root Caries Without Dental Scaling Among Community-dwelling Elderly.

PURPOSE: The purpose of this clinical research was to analyze the effectiveness of DIAGNOdent in detecting root caries without dental scaling. MATERIALS AND METHODS: The status of 750 exposed, unfilled root surfaces was assessed by visual-tactile examination and DIAGNOdent before and after root scaling. The sensitivity and specificity of different cut-off DIAGNOdent values in diagnosing root caries with reference to visual-tactile criteria were evaluated on those root surfaces without visible plaque/calculus. The DIAGNOdent values from sound and carious root surfaces were compared using the nonparametric Mann-Whitney U-test. The level of statistical significance was set at 0.05. RESULTS: On root surfaces without plaque/calculus, significantly different (p < 0.05) DIAGNOdent readings were obtained from sound root surfaces (12.2 ± 11.1), active carious root surfaces (37.6 ± 31.7) and inactive carious root surfaces (20.9 ± 10.5) before scaling. On root surfaces with visible plaque, DIAGNOdent readings obtained from active carious root surfaces (29.6 ± 20.8) and inactive carious root surfaces (27.0 ± 7.2) were not statistically significantly different (p > 0.05). Furthermore, on root surfaces with visible calculus, all DIAGNOdent readings obtained from sound root surfaces were > 50, which might be misinterpreted as carious. After scaling, the DIAGNOdent readings obtained from sound root surfaces (8.1 ± 11.3), active carious root surfaces (37.9 ± 31.9) and inactive carious root surfaces (24.9 ± 11.5) presented significant differences (p < 0.05). A cut-off value between 10 and 15 yielded the highest combined sensitivity and specificity in detecting root caries on root surfaces without visible plaque/calculus before scaling, but the combined sensitivity and specificity are both around 70%. CONCLUSION: These findings suggest that on exposed, unfilled root surfaces without visible plaque/calculus, DIAGNOdent can be used as an adjunct to the visual-tactile criteria in detecting root-surface status without pre-treatment by dental scaling.

Effect of laser irradiation on the fluoride uptake of silver diamine fluoride treated dentine.

This study aimed to evaluate the fluoride uptake of dentine treated with a 38 % silver diamine fluoride (SDF) solution and laser irradiation at sub-ablative energy levels. Fifteen human dentine slices were prepared and divided into four samples each. Four types of laser were chosen: CO2 (10,600 nm), Er:YAG (2,940 nm), Nd:YAG (1,064 nm) and Diode (810 nm). First, the four samples from 12 of the dentine slices were treated with SDF, and then irradiated by one of the four types of laser at three different settings. One sample was untreated and acted as a control. The setting that rendered the highest fluoride uptake was selected. Second, the remaining dentine slices were treated with SDF and irradiated by the four lasers with the selected settings. Fluoride uptake was assessed using Energy Dispersive X-ray Spectrometry at the dentine surface and up to 20 µm below the surface. The selected settings were CO2 irradiation at 1.0 W for 1 s, Er:YAG irradiation at 0.5 W for 20 s, Nd:YAG irradiation at 2.0 W for 1 s and diode irradiation at 3.0 W for 3 s. The fluoride content (weight %) at the dentine surface following CO2, Er:YAG, Nd:YAG and diode irradiation was 6.91 ± 3.15, 4.09 ± 1.19, 3.35 ± 2.29 and 1.73 ± 1.04, respectively. CO2 and Er:YAG irradiation resulted in higher fluoride uptake than Nd:YAG and diode irradiation at all levels (p < 0.05). CO2 laser and Er:YAG laser irradiation rendered higher fluoride uptake in the SDF-treated dentine than Nd:YAG laser and diode laser irradiation.

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.

Oral cavity cancer trends over the past 25 years in Hong Kong: a multidirectional statistical analysis.

BACKGROUND: Even though oral cavity cancer (OCC; ICD 10 codes C01, C02, C03, C04, C05, and C06) ranks eleventh among the world's most common cancers, accounting for approximately 2 % of all cancers, a trend analysis of OCC in Hong Kong is lacking. Hong Kong has experienced rapid economic growth with socio-cultural and environmental change after the Second World War. This together with the collected data in the cancer registry provides interesting ground for an epidemiological study on the influence of socio-cultural and environmental factors on OCC etiology. METHODS: A multidirectional statistical analysis of the OCC trends over the past 25 years was performed using the databases of the Hong Kong Cancer Registry. The age, period, and cohort (APC) modeling was applied to determine age, period, and cohort effects on OCC development. Joinpoint regression analysis was used to find secular trend changes of both age-standardized and age-specific incidence rates. RESULTS: The APC model detected that OCC development in men was mainly dominated by the age effect, whereas in women an increasing linear period effect together with an age effect became evident. The joinpoint regression analysis showed a general downward trend of age-standardized incidence rates of OCC for men during the entire investigated period, whereas women demonstrated a significant upward trend from 2001 onwards. CONCLUSIONS: The results suggest that OCC incidence in Hong Kong appears to be associated with cumulative risk behaviors of the population, despite considerable socio-cultural and environmental changes after the Second World War.

Non-surgical treatment of dentin caries in preschool children--systematic review.

BACKGROUND: Untreated dentin caries in primary teeth is commonly found in preschool children worldwide. Recently, the use of simple non-surgical approaches to manage the situation has been advocated. The aim of the study was to systematically review and evaluate the literature on effectiveness of non-surgical methods in arresting or slowing down the progression of active dentin caries in primary teeth in preschool children. METHODS: A systematic search of the main electronic databases (Pubmed, Cochrane Collaboration, EMBASE) was conducted to identify peer reviewed papers published in English in the years 1947-2014. Keywords and MeSH terms used in the search were "dental caries", "primary dentition" and various non-surgical treatments (fluoride, sealant, resin infiltration, xylitol, chlorhexidine, CPP-ACP, ozone, etc.). The inclusion criteria were clinical studies conducted in children under 6 years old, and reported findings on caries arrest or caries progression in primary teeth. Retrieved papers were read by two reviewers independently to assess suitability for inclusion, and the final decision was made by consensus. Quality of the included studies was assessed and data were extracted for analysis. RESULTS: The search identified 323 papers for screening. Among these, 290 papers did not satisfy the study inclusion criteria. Consequently, 33 full papers were retrieved and reviewed. Finally, 4 studies were included. Three studies reported that topical applications of silver diammine fluoride (SDF) solution could arrest dentin caries in preschool children. One study supported that having a daily toothbrushing exercise in kindergarten using toothpaste with 1000 ppm fluoride could stabilize the caries situation in young children. CONCLUSIONS: There is limited evidence to support the effectiveness of SDF applications or daily toothbrushing with fluoride toothpaste in arresting or slowing down the progression of active dentin caries in primary teeth in preschool children. More well-designed randomized controlled trials are required to confirm these findings.

Factors influencing treatment decision-making for maintaining or extracting compromised teeth.

AIMS: To evaluate treatment decision-making with respect to maintaining periodontally compromised teeth among dentists with or without postgraduate qualifications in implant dentistry. MATERIAL AND METHODS: A series of patient scenarios with varying degrees of periodontal disease levels was presented to dental practitioners. Practitioners' decision-making outcome was determined, and intention to retain the compromised teeth was analyzed in bivariate and regression analyses (accounting for postgraduate implant training, gender, years in dental practice, and implant placement experience). RESULTS: This study involved 30 dental practitioners with postgraduate implant qualifications (GDPP), 33 dental practitioners without postgraduate implant qualifications (GDP), and 27 practitioners undergoing training for postgraduate implant qualifications (GDPT). Variations in treatment decision-making were evident between the three groups. Differences in treatment approaches to retaining compromised teeth were apparent. Furthermore, variations in rehabilitation of extracted scenarios existed in terms of use of implant and number of implants need for rehabilitation. Accounting for dentist and practice factors in regression analyses, GDPP/GDPT were three times as likely to retain periodontally compromised upper molar, with or without pain, compared to GDP (without pain OR 3.10, 95%CI 1.04, 10.62 P = 0.04; with pain OR 3.08, 95%CI 1.09, 8.14 P = 0.03). CONCLUSION: Variations in treatment decision-making with respect to retaining periodontally compromised teeth exist between dental practitioners with and those without postgraduate training in implant dentistry. Furthermore differences in management approaches in how they would retain the teeth or rehabilitate the dental arch were apparent.

Sealant retention is better assessed through colour photographs than through the replica and the visual examination methods.

The aim of this study was to test the hypothesis that the colour photograph method has a higher level of validity for assessing sealant retention than the visual clinical examination and replica methods. Sealed molars were assessed by two evaluators. The scores for the three methods were compared against consensus scores derived through assessing retention from scanning electron microscopy images (reference standard). The presence/absence (survival) of retained sealants on occlusal surfaces was determined according to the traditional and modified categorizations of retention. Sensitivity, specificity, and Youden-index scores were calculated. Sealant retention assessment scores for visual clinical examinations and for colour photographs were compared with those of the reference standard on 95 surfaces, and sealant retention assessment scores for replicas were compared with those of the reference standard on 33 surfaces. The highest mean Youden-index score for the presence/absence of sealant material was observed for the colour photograph method, followed by that for the replica method; the visual clinical examination method scored lowest. The mean Youden-index score for the survival of retained sealants was highest for the colour photograph method for both the traditional (0.882) and the modified (0.768) categories of sealant retention, whilst the visual clinical examination method had the lowest Youden-index score for these categories (0.745 and 0.063, respectively). The colour photograph method had a higher validity than the replica and the visual examination methods for assessing sealant retention.

Factors related to children's caries: a structural equation modeling approach.

BACKGROUND: Dental caries among preschool children is highly prevalent in many less-developed countries. METHODS: A model which explored the factors related to children's dental caries was tested in this study using structural equation modeling. Caregivers of children aged 5 years were surveyed on their socioeconomic status, and their oral health knowledge, attitudes and practices. In addition, information on their children's oral health practices, dental insurance and dental service utilization were collected. Examination of caries was conducted on all children who returned fully completed questionnaires. RESULTS: The results showed that socioeconomic factors influenced children's oral health practices through the impact of caregivers' oral health knowledge and practices; that caregivers' oral health knowledge affected children's oral health practices through the influence of caregivers' oral health attitudes and practices; and finally, that children's oral health practices were linked directly to their caries. CONCLUSION: The findings have important applications for promoting policies aimed at advancing children's oral health.

Prevention of dentine caries using silver diamine fluoride application followed by Er:YAG laser irradiation: an in vitro study.

To evaluate the preventive effect of Er:YAG laser (EYL) irradiation followed by silver diamine fluoride (SDF) application on dentine with cariogenic biofilm challenge. Twenty-four dentine slices were prepared from extracted sound human third molars. Each slice was cut into four parts for SDF application, followed by EYL irradiation (group SL), SDF application (group S), EYL irradiation (group L) and water (group W). The specimens were subjected to cariogenic biofilm challenge for 12 h, followed by immersion in a buffered remineralising solution containing calcium chloride and sodium hypophosphate for 12 h at 37 °C. Surface morphological changes in the specimens were examined using scanning electronic microscopy. Elemental analysis was performed using energy-dispersive X-ray spectrometry. Micro-mechanical properties were investigated by nano-indentation. The specimen surfaces of groups SL and L showed laser melting contours with narrowed dentinal orifices. Group S showed a partial tubular occlusion. A porous surface was observed in group W, indicating demineralisation. The mean (SD) fluoride weight percentages were 3.93 (0.91), 3.10 (0.61), 0.17 (0.09) and 0.32 (0.07) in groups SL, S, L and W, respectively, (p < 0.001; SL, S > L, W). The mean (SD) micro-hardness values in GPa were 1.84 (0.22), 0.49 (0.13), 0.41 (0.11) and 0.30 (0.06) in groups SL, S, L and W, respectively, (p < 0.001; SL > S > L, W). The mean (SD) elastic moduli in GPa were 75.1 (7.2), 20.0 (1.3), 24.3 (5.2) and 20.2 (2.8) in groups SL, S, L and W, respectively, (p < 0.001; SL > S, L, W). SDF application followed by EYL irradiation on a dentine surface increased its resistance to cariogenic biofilm challenge.

Unique morphologic and clinical features of liver predominant/primary small cell carcinoma--autopsy and biopsy case series.

Liver predominant small cell carcinoma is rare but often presents as hyperacute liver failure with unknown primary and is a medical emergency. We present 2 autopsy and 7 biopsy cases of liver predominant small cell carcinoma and demonstrate that these patients present with liver failure and identifiable hepatomegaly but lack discrete lesions on imaging as well as no mass lesions identified in other organs including lung. Compared with the multiple nodules of metastatic small cell carcinoma in the liver, unique morphologic feature of liver predominant/primary small cell carcinoma in autopsy and biopsy specimens was a diffuse infiltration of small blue neoplastic cells predominantly in the sinusoidal space in the liver parenchyma. Before diagnosing liver predominant/primary small cell carcinoma, other infiltrating small blue cell neoplasms including lymphoma and peripheral neuroectodermal tumor need to be ruled out through immunohistochemistry. We, therefore, demonstrate that liver biopsy together with a rapid panel of immunostains is necessary to firmly establish a diagnosis of liver predominant small cell carcinoma and allow clinicians to immediately implement potentially lifesaving chemotherapy.