Al and Fe levels in mixed saliva of children related to elution behavior from teeth and restorations

Abstract

Objectives The levels of trace elements in mixed saliva were not well-defined. This study was performed to determine Al and Fe concentrations in mixed saliva of children and to investigate the relationship between these levels and dental caries. Methods Among 562 collected mixed saliva specimens, 514 and 548 samples for analyses of Al and Fe levels were obtained, respectively. The Al and Fe concentrations were determined using flameless atomic absorption spectrometry. Results The Al and Fe concentrations in children without a history of caries were 0.093 ± 0.136 and 0.121 ± 0.128 μg/mL, respectively. The Fe level depended on sex. The Fe level in girls who experienced caries was significantly higher than that without caries history. The Al and Fe levels were significantly higher in children with treated caries than children without caries history. The Fe concentrations were affected by restoration type. Composite resin increased the Fe level significantly especially in girls, and the Fe level was also higher in boys treated with both composite resin and metal restorations. In children without caries history, the Al level was inversely proportional to the number of deciduous teeth and increased with the number of permanent teeth. In contrast, the Fe level showed the reverse tendency. Conclusions The Fe level in mixed saliva of children was influenced by the restoration type. It was suggested that Al was eluted more from sound permanent teeth than sound deciduous teeth, while Fe was eluted in the opposite manner.