Background: Dental caries in primary teeth is a serious oral health concern among children. It can lead to detrimental impacts on a child's growth, development, and quality of life. Therefore, this cross-sectional study aimed to examine the prevalence of dental caries and its associations with nutritional status, sugar and secondhand smoke exposure among pre-schoolers. Methods: A total of 26 pre-schools in Seremban, Malaysia were randomly selected using the probability proportional to size sampling. Dental examination was performed by a dentist to record the number of decayed teeth (dt). Weight and height of the pre-schoolers were measured. The mother-administered questionnaire was used to gather information pertaining to the sociodemographic characteristics and secondhand smoke exposure. Total sugar exposure was calculated from a 3-day food record. Results: Among the 396 participating pre-schoolers, 63.4% of them had at least one untreated caries, with a mean ± SD dt score of 3.56 ± 4.57. Negative binomial regression analysis revealed that being a boy (adjusted mean ratio = 1.42, 95% CI = 0.005-0.698, p = 0.047), exposed to secondhand smoke (adjusted mean ratio = 1.67, 95% CI = 0.168-0.857, p = 0.004) and those who had more than 6 times of daily total sugar exposure (adjusted mean ratio = 1.93, 95% CI = 0.138-0.857, p = 0.013) were significantly associated with dental caries among pre-schoolers. Conclusion: A high prevalence of dental caries was reported in this study. This study highlights the need to reduce exposure to secondhand smoke and practice healthy eating behaviours in reducing the risk of dental caries among pre-schoolers.

The synthesis of bulk Y2Ba4Cu7O15‐δ superconductor at atmospheric oxygen pressure via solid state sintering is reported. Temperature ranging from 860 to 890 °C as well as time interval over 2 to 15 days were used to investigate the formation of the Y2Ba4Cu7O15‐δ phase. A time‐temperature profile characterizing the conditions for the preparation of Y2Ba4Cu7O15‐δ phase suggests the optimal condition to be sintering at 890 °C for over 10 days. Detailed results of X‐ray diffraction, electrical resistivity, iodometric titration and magnetization measurements are described.