Association of characteristics of delivery and medical conditions during the first month of life with developmental defects of enamel.

BACKGROUND: Developmental defects of enamel (DDE) may be influenced by health problems and illness in children. The aim of the study was to identify the main characteristics of birth (delivery) and adverse medical conditions during the first month of life that may be related to DDE in permanent teeth. METHODS: 1000 schoolchildren between the ages of 9 and 11 years were selected for this cross-sectional study by multistage randomization from four educational zones in Shiraz in 2013. Intraoral examination was used to diagnose DDE according to World Health Organization screening guidelines and the Modified DDE Index. The data on seven birth factors as well as health and nutritional conditions during the first month of life were collected by a questionnaire completed by the parents, and were analyzed with the chi-squared test, Spearman's correlation and binary logistic regression. RESULTS: 469 (48.2%) out of 974 schoolchildren had at least one permanent tooth with DDE. The defects were significantly related with Apgar score at birth <7 (p = 0.003) and illness during the first month (p = 0.035). The frequency of DDE was significantly lower in the third child in families compared to the first and second child (p = 0.005). However, DDE showed no significant relationship with gestational age, delivery type, birth weight, gender or type of feeding during early infancy. CONCLUSIONS: Three associated factors were identified (birth Apgar score, illness during the first month of life, birth order) for DDE in permanent teeth. No specific illness was found to be significantly associated with DDE

The clinical application of Circulating tumor cells and DNAs as prognostic and predictive biomarkers in gastrointestinal cancer

Gastrointestinal (GI) cancer is one of the most common cancers globally. Genetic and epigenetic mechanisms are involved in its pathogenesis. The conventional methods for diagnosis and screening for GI cancers are often invasive and have other limitations. In the era of personalized medicine, a novel non-invasive approach called liquid biopsy has been introduced for the detection and management of GI cancers, which focuses on the analysis of circulating tumor cells (CTCs) and circulating cell-free tumor DNA (ctDNA). Several studies have shown that this new approach allows for an improved understanding of GI tumor biology and will lead to an improvement in clinical management. The aim of the current review is to explore the clinical applications of CTCs and ctDNA in patients with GI cancer. Key words: Gastrointestinal cancer; Liquid biopsy; CTCs; ctDNA; biomarkers; tumor biolog

Assessing the Relationship between Dental Caries and Anthropometric Indices in 9-11-Year-old Primary School Children of Shiraz

Abstract Background and aim: Dental caries is the most prevalent chronic childhood disease that has a profound impact on the health of both the individual and community health. On the other, the overweight and underweight in children is a major public health concern influenced by common factors with dental caries. The aim of the present study was to assess the relationship between DMFT (Decay-Missing-Filled-permanent teeth) and anthropometry indices in 9-11 year old primary school children of the city of Shiraz, Iran-2012. Methods: The present cross-sectional study was conducted on primary school children, aged 9 to 11 years, selected by cluster random sampling in four areas of Shiraz city, in 2012. The prevalence of children with dental caries was calculated by measuring the number of teeth decayed, missing or filled duo to caries (DMFT) indices using the WHO screening standards. Weight, height, and sitting height were measured and body mass index (BMI) and leg height were calculated. The association between Anthropometry and DMFT were examined using bivariate correlation and linear regression tests by the SPSS software. The difference mean DMFT index between five groups of BMI was evaluated by ANOVA and post hoc Tukey tests. Results: A total of 974 pupils were studied. Mean DMFT was 0.94±1.46. There were significant association between DMFT and BMI (r=-0/91 p=0/005). Mean DMFT was significantly reduced from underweight children to obese children (p=0/027). Conclusion: Underweight children have a higher risk of developing caries in their permanent teeth. Key words: Body Mass Index, Anthropometry, DMF Inde

Unerupted Primary Molar Teeth Positioned Inferior to the Permanent Premolar: A Case Report

Primary tooth impaction is a rare finding during the development of primary dentition. Several factors contribute to the impaction of a deciduous tooth. This report describes the diagnosis and treatment of a 10-year-old boy who presented an impacted second primary mandibular molar. This tooth, located inferior to the second premolar together with an odontoma, was positioned superior to the premolar teeth. Treatment consisted of surgical removal of the impacted deciduoustooth and odontoma and placement of a passive lower lingual holdingarch. Periodic examination was indicated for follow- up. Early intervention was recommended to manage orofacial disfigurement and to avoid consequent problems

A practicable and reliable test for metal powder spreadability : development of test and analysis technique

A crucial step in the powder bed metal additive manufacturing process is the formation of a thin layer of powder on top of the existing material. The propensity of the powder to form thin layers under the conditions used in additive manufacturing is critically important, but no test method has yet been established to measure this characteristic, which is sometimes referred to as spreadability. The current work spreads a single layer of powder using commercial equipment from the paint and food industries and derives the density of a layer of powder, which is of a similar thickness to that in additive manufacturing. Twenty-four powders from eight suppliers have been tested and the density of the layers has been measured as a function of various parameters. Twenty-two of the powders successfully form thin layers, with a density of at least 40% of each powder’s apparent density. Hall flow time did not correlate with the spread layer density, although the two powders that did not spread did not pass through the Hall funnel. The roughness of the plate onto which the powder was spread, the recoater speed, the layer thickness, particle size and aspect ratio all affect the measured layer density. Results of the new test are repeatable and reproducible. These findings can be used to develop a test for spreadability for metal powders that can be used for additive manufacturing, which will help to improve the quality of printed components. QC 20230524</p