Potentiometric stripping analysis of lead and cadmium leaching from dental prosthetic materials and teeth

The release of zinc, copper, lead, and cadmium from the mineral tissue of teeth under the influence of soft drinks and sour-tasting food

This study was carried out with the aim of identifying the effects of consuming sour-tasting food and refreshing drinks on the bone tissue of teeth among teenagers. The cumulative effect of a year-long exposure of teeth to the erosive effects of a model system of acidic media (citric acid, lactic acid, acetic acid, apple vinegar, lemonade, the soft drink Sprite, mineral water) was studied. The effects were registered based on the amount of released biometal ions, of zinc and copper, and toxic lead, during a period of 24 hr at room temperature, using the potentiometric stripping analysis. In the given time span, amounts ranging from 75 to 750 ppm of zinc, from 0.1 to 1.0 ppm of copper, and up to 1.5 ppm of lead were released from the dental matrix, while the release of cadmium was below the level of detection. The changes to the mineral structure of the bone tissue were monitored by the Fourier's transformation infrared spectroscopy and scanning electron microscopy technique. These studies have shown that under the influence of an acidic medium significant erosion to the tooth enamel ensues and that the eroded surfaces had a radius of 1-5 μm.

Monitoring the effects of exposure to lead and cadmium in working and living environment through standard biochemical blood parameters and liver endonucleases activity

Heavy metals as pollutants in the working and living environment are a serious health and environmental problem because they are toxic, non-biodegradable, accumulate in living systems and have a long half-life in soil. Sources of lead contamination are combustion products in the chemical industry and metallurgy, industrial waste water, landfills, traffic etc. Lead enters into the body via the food chain and drinking water. In the body lead is deposited in the liver, kidneys, brain and mineral tissues. Excretion of lead causes damage to the epithelial cells of certain organs. High level exposure to cadmium is usually the result of environmental pollution by human activities. Exposure to cadmium can lead to acute and chronic tissue damage of various organs, including liver and kidneys in humans and in animals. In this paper we analyzed the effects of lead and cadmium exposure, in working and living environment, on the model system of experimental animals, particularly the activity of certain liver enzymes, acid and alkaline DNase, and standard biochemical blood parameters. The study showed that lead and cadmium significantly affect the protein content, red blood cells, hemoglobin and hematocrit, and the activity of liver enzymes. This harmful effect of this toxic metal can be reduced by the supplements.

Copper release from dental prosthetic crowns, dental materials, and human teeth into acetic acid

This article examines the dilution of the ion of copper from human teeth and dental prosthetic crowns in 4% CH(3)COOH during a period of 24 hr at room temperature. The content of the diluted copper in an acetate extract, as well as the overall content of this metal in the samples, was determined by means of a potentiometric stripping analysis. The comparative measurements were carried out using the furnace atomic absorption spectrophotometry technique, which is recommended by the International Standards (ISO 6872:2008; ISO 24234:2004) as a method for quality control of dental-prosthetic material (dental ceramic, metal restorative materials, dental amalgams) in the process of checking for heavy metals. During a 24-hr period in 4% CH(3)COOH at a temperature of 25 degrees C, approximately 72% of the overall copper was released from the tooth. The percentage of the released copper from baby teeth is higher, ranging from 88 to 92%, which is probably a consequence of the bone tissue being in development, its infirmity, and inadequate stability. On these conditions, approximately 72% of the overall copper was released from the dental-ceramic prosthetic crowns.

Potentiometric stripping analysis of zinc and copper in human teeth and dental materials

Potentiometric stripping analysis (PSA) with oxygen as the oxidant has been used to determine soluble zinc and copper levels in exfoliated human teeth (all of which required extraction for orthodontic reasons) and commercial dental materials. The soluble zinc and copper contents of teeth were slightly below the zinc and copper contents in whole teeth reported by other researchers, except in the case of tooth with removed amalgam filling. Soluble zinc and copper concentrations of the dental materials and metal ceramic crowns were 0.50-6.30, and of 2.00-4.30 microg/g, respectively. The results of this work suggest that PSA may be a good method for zinc and copper leaching studies during the investigation of dental prosthetic materials' biocompatibility. Corrosive action of acidic media as evidenced by SEM micrographs caused the leaching of metal ions from teeth.

The role of synthetic biomaterials in resorptive alveolar bone regeneration

The alveolar bone tissue resorption defect has a significant role in dentistry. Because of the bone tissue deficit developed by alveolar resorption, the use of synthetic material CP/PLGA (calcium-phosphate/polylactide-co-gliycolide) composite was introduced. Investigations were performed on rats with artificially produced resorption of the mandibular bone. The results show that the best effect on alveolar bone were attained by using nano-composite implants. The effect of the nanocomposite was ascertained by determining the calcium and phosphate content, as a basis of the hydroxyapatite structure. The results show that synthetic CP/PLGA nanocomposite alleviate the rehabilitation of weakened alveolar bone. Due to its osteoconductive effect, CP/PLGA can be the material of choice for bone substitution in the future.