Crystallinity, solubility, and dissolution rate behavior of fluoridated CO3 apatites

Area of Science:

• Materials Science
• Biomineralization
• Dental Research

Background:

• Carbonate apatites are crucial in biological hard tissues.
• Fluoride incorporation modifies apatite properties, impacting dental health.
• Understanding fluoride's effect on carbonate apatites is key for biomaterials.

Purpose of the Study:

• To investigate how varying fluoride levels affect the physicochemical properties of carbonate-containing apatites.
• To analyze changes in crystal structure, crystallinity, and solubility.
• To compare these effects with those observed in fluoridated hydroxyapatites.

Main Methods:

• Synthesis of two series of fluoridated CO3 apatites at 80°C and pH 7.4.
• Characterization of alpha-axis dimensions and crystallinity.
• Measurement of apparent solubility in acetate buffer solutions (pH 4.0, 6.0) at 37°C.
• Assessment of dissolution rates of apatite pellets at pH 4.0.

Main Results:

• Alpha-axis dimensions decreased with increasing fluoride and carbonate content.
• Crystallinity patterns varied similarly with fluoridation, regardless of carbonate content.
• Apparent solubility and dissolution rates decreased monotonically with higher fluoride content.
• Fluoridated CO3 apatites showed increased acid resistance at higher fluoride levels.

Conclusions:

• Fluoride incorporation significantly alters the physicochemical properties of carbonate apatites.
• Increased fluoridation enhances apatite stability and reduces solubility and dissolution rates.
• Findings provide insights into fluoride's role in biomineralization and dental caries prevention.