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.

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.

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.

Influence of trophic overlaps and trophic niche amplitude on microplastic intake of fish species in shallow areas of a neotropical coastal lagoon.

Plastic pollution is a global challenge that affects all marine ecosystems, and reflects all types of uses and activities of human society in these environments. In marine ecosystems, microplastics and mesoplastics interact with invertebrates and become available to higher predators, such as fish, which can ingest these contaminants. This study aimed to analyze how ecological food interactions (diet overlap and trophic niche amplitude) among fish species contribute to the ingestion of plastic particles. The gastrointestinal contents of six fish species (Atherinella brasiliensis, Eucinostomus melanopterus, Eucinostomus argenteus, Genidens genidens, Coptodon rendalli, and Geophagus brasiliensis) were analyzed to identify prey items and plastic ingestion. Based on the ontogenetic classification, A. brasiliensis, E. melanopterus, and G. genidens were divided into juveniles and adults, and the six fish species analyzed were divided into nine predator groups. Most of the plastics ingested by the fish species were blue microplastic (MP) fibers (< 0.05 mm) classified as polyester terephthalate, polyethylene, and polybutadiene. Considering all the analyzed predators, the average number and weight of plastics ingested per individual were 2.01 and 0.0005 g, respectively. We observed that predators with a high trophic overlap could present a relationship with the intake of MP fibers owing to predation on the same resources. In addition, we observed the general pattern that when a species expands its trophic diversity and niche, it can become more susceptible to plastic ingestion. For example, the species with the highest Levin niche amplitude, E. argenteus juveniles, had the highest mean number (2.9) of ingested MP fibers. Understanding the feeding ecology and interactions among species, considering how each predator uses habitats and food resources, can provide a better understanding of how plastic particle contamination occurs and which habitats are contaminated with these polluting substances.

Understanding of the role of serum creatinine in a subset of the Brazilian population.

INTRODUCTION: Chronic kidney disease is usually asymptomatic, and its diagnosis depends on laboratory tests, with emphasis on serum creatinine and proteinuria. OBJECTIVE: To assess knowledge on the role of serum creatinine as a biomarker of kidney function in a sample of the Brazilian population. METHOD: Cross-sectional observational study conducted in São Paulo (SP, Brazil), in which a random adult population was interviewed. RESULTS: A total of 1138 subjects were interviewed, with a median age of 36 years old (27-52); 55.1% were female. Regarding the "creatinine" biomarker, 40.6% stated they had never performed such a test. When asked about their knowledge on the usefulness of this exam, only 19.6% knew its function. The other responses were "I don't know" (71.6%), evaluating heart function (0.9%) and liver function (7.8%). Of those who reported they had already taken a creatinine test, only 29.4% correctly identified the role of creatinine. When dividing the groups into "knows" and "does not know" the function of creatinine, a statistically significant difference (p < 0.05) was observed regarding level of education, female sex, being a healthcare student/worker, having ever measured creatinine, knowing someone with kidney disease and older age. In the multivariate analysis, the main variable related to knowing the creatinine role was having previously taken the test (OR 5.16; 95% CI 3.16-8.43, p < 0.001). CONCLUSION: There is a significant lack of knowledge about creatinine and its use in checkups. The results indicate that greater efforts are needed from healthcare professionals to raise awareness on the role of serum creatinine.

Understanding of the role of serum creatinine in a subset of the Brazilian population / Conhecimento de uma amostragem da população brasileira sobre a função da creatinina sérica

Abstract Introduction: Chronic kidney disease is usually asymptomatic, and its diagnosis depends on laboratory tests, with emphasis on serum creatinine and proteinuria. Objective: To assess knowledge on the role of serum creatinine as a biomarker of kidney function in a sample of the Brazilian population. Method: Cross-sectional observational study conducted in São Paulo (SP, Brazil), in which a random adult population was interviewed. Results: A total of 1138 subjects were interviewed, with a median age of 36 years old (27-52); 55.1% were female. Regarding the "creatinine" biomarker, 40.6% stated they had never performed such a test. When asked about their knowledge on the usefulness of this exam, only 19.6% knew its function. The other responses were "I don't know" (71.6%), evaluating heart function (0.9%) and liver function (7.8%). Of those who reported they had already taken a creatinine test, only 29.4% correctly identified the role of creatinine. When dividing the groups into "knows" and "does not know" the function of creatinine, a statistically significant difference (p < 0.05) was observed regarding level of education, female sex, being a healthcare student/worker, having ever measured creatinine, knowing someone with kidney disease and older age. In the multivariate analysis, the main variable related to knowing the creatinine role was having previously taken the test (OR 5.16; 95% CI 3.16-8.43, p < 0.001). Conclusion: There is a significant lack of knowledge about creatinine and its use in checkups. The results indicate that greater efforts are needed from healthcare professionals to raise awareness on the role of serum creatinine.

Resumo Introdução: A doença renal crônica costuma ser assintomática e seu diagnóstico depende da realização de exames laboratoriais, com destaque para a creatinina sérica e pesquisa de proteinúria. Objetivo: Avaliar em uma amostra da população brasileira o conhecimento sobre o papel da creatinina sérica como marcador de função renal. Método: Estudo observacional transversal realizado na cidade de São Paulo (SP, Brasil), em que foi entrevistada uma população adulta aleatória. Resultados: Foram entrevistados 1138 indivíduos, com idade mediana de 36 anos (27-52); 55,1% do sexo feminino. Com relação ao marcador "creatinina", 40,6% afirmaram que nunca realizaram tal dosagem. Quando questionados quanto ao conhecimento sobre a utilidade desse exame, somente 19,6% sabiam a sua função. As outras respostas foram "não sei" (71,6%), avaliar o funcionamento do coração (0,9%) e fígado (7,8%). Dos que afirmaram já terem realizado o exame de creatinina, somente 29,4% acertaram a função da creatinina. Ao dividir os grupos em "sabe" e "não sabe" a função da creatinina, percebeu-se diferença estatisticamente significante (p < 0,05) em relação ao grau de escolaridade, sexo feminino, ser aluno/trabalhador da saúde, ter dosado creatinina alguma vez, conhecer alguém com doença renal e maior idade. Na análise multivariada, a principal variável relacionada com conhecer a função da creatinina foi ter realizado o exame anteriormente (OR 5,16; IC 95% 3,16-8,43, p < 0,001). Conclusão: Há grande desconhecimento sobre a creatinina e seu uso em check-ups. Os resultados indicam que é necessário maior esforço por parte dos profissionais de saúde para divulgar o papel da creatinina sérica.

Prevention of secondary caries by silver diamine fluoride.

PURPOSE: This study aimed to investigate the use of 38% silver diamine fluoride (SDF) as a treatment for preventing secondary caries in glass ionomer cement (GIC) and composite resin (CR) restorations. METHODS: Six extracted human sound premolars were collected. Four cavities (4 × 2 × 2 mm(3) ) were prepared on each premolar and then allocated to the following restoration groups: group 1, SDF conditioning and GIC restoration; group 2, GIC restoration; group 3, SDF conditioning and CR restoration; and group 4, CR restoration. After thermal cycling and sterilisation, the teeth were soaked in a 5% sucrose solution containing Streptococcus mutans and Lactobacillus acidophilus for 28 days. Micro-computed tomography was used to study demineralisation. The outer lesion depth (OLD) and wall lesion depth (WLD) of the tooth-restoration interface were measured. The OLD and WLD were directly related to the extent of secondary caries. Two-way analysis of variance was used to analyse the effects of SDF conditioning and restorative materials on OLD. RESULTS: The mean ± standard deviation OLD values were 156 ± 45 µm, 235 ± 33 µm, 153 ± 20 µm and 232 ± 24 µm for groups 1-4, respectively. The OLD was less in restorations with SDF conditioning (P < 0.001) than in those without SDF conditioning. No interaction effect on OLD was found between the restorative materials and SDF conditioning (P = 0.062). The WLD was detected only in groups 3 and 4. CLINICAL SIGNIFICANCE: Conditioning with 38% SDF can increase resistance of GIC and CR restorations to secondary caries.