Etermination, analysis and comparison of the presence of essential and potentially toxic microelements in different regions of enamel and dentin

• Grant number: 22/00626-6
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: July 01, 2022
• End date: June 30, 2025
• Field of knowledge: Health Sciences - Pharmacy - Toxicological Analysis
• Principal Investigator: Raquel Fernanda Gerlach
• Grantee: Natalia de Macedo Ribeiro
• Host Institution: Faculdade de Odontologia de Ribeirão Preto (FORP). Universidade de São Paulo (USP). Ribeirão Preto , SP, Brazil

Abstract

Dental enamel and dentin have very variable concentrations of the different chemical elements, and the concentrations also vary in different parts of the enamel and at different depths of the dentin. Currently, these variations are not taken into account when measuring microelements in teeth, and this is one of the most important factors for having very discrepant data on microelements in teeth. On the other hand, when the type of mineralization is taken into account and clean techniques are used to obtain samples, teeth are excellent repositories of enamel peptides and it is also possible to detect several toxic and essential microelements. However, as the "usual" values of microelements in different parts of teeth and in teeth of different origins are unknown, information on microelements is not used yet. There is also still no correlation between the amounts of microelements found in enamel and dentin and the levels of these microelements in plasma during the formation of the hard tissues of the tooth. Therefore, our objective is to determine the concentrations of some microelements in different parts of dentin and enamel, verify their distribution and if there are associations between the distribution of these elements. The microelements tested will be mercury (Hg), manganese (Mn), zinc (Zn), arsenic (As), lead (Pb), cadmium (Cd) and fluoride (F). For the study, 32 deciduous teeth will be used (per group) collected in schools in Ribeirão Preto, SP, in the years 2017 and 2018. The regions that will be tested are the surface enamel, the internal enamel, the prenatal dentin and the dentin next to the pulp. Data will be expressed as ug/g or ng/g of enamel or dentin, based on measurements of Ca. The results of this study could be important to provide a solid foundation for how to use teeth (and their different parts) to obtain microelement measurements. Possibly in the future, teeth can be used again as reliable indicators of exposure to contaminants, as well as in the study of microelement deficiencies in different populations, which today is not possible due to the lack of knowledge on the distribution of minerals in different parts of the teeth. (AU)