Chitosan and sodium fluoride for the sustainable preservation of skeletal remains
Abstract
This paper presents two substances that can be used together or apart (depending on the chemistry of the bones to be treated) for the conservation of bone: sodium fluoride and chitosan. Unlike traditional consolidation techniques with synthetic polymers, this approach addresses both the inorganic (mineral) and organic (collagen) components of bone. Sodium fluoride promotes remineralization by forming fluorapatite, which enhances stability, while chitosan, a biopolymer with antibacterial properties, can compensate for lost collagen, improving mechanical resistance. Their application since 1995 at the CNCPC in Mexico, has been successful in treating historical and fossilized remains. It prevents microbial growth and is less invasive than other conservation techniques because it does not create superficial layers or mineral fillings, making it suitable for conservation while maintaining structural integrity. The characteristics of both substances make them a more sustainable option for treating bones than the traditional ones. The study includes detailed preparation procedures, application methods, and case studies demonstrating the technique’s effectiveness.
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