Microstructural Analysis of Cancellous Bone in Fluorosis Rats

Area of Science:

• Biomineralization
• Skeletal Biology
• Toxicology

Background:

• Skeletal fluorosis alters bone structure due to fluoride's replacement of bone mineral.
• Previous research indicated high bone turnover in cortical bone affected by skeletal fluorosis.
• This study investigates the impact of fluoride on cancellous bone microstructure.

Purpose of the Study:

• To analyze the microstructural changes in cancellous bone of rats exposed to excessive fluoride.
• To evaluate the effects of different fluoride doses and exposure durations on bone parameters.
• To assess the relationship between fluoride exposure, oxidative stress, and cancellous bone integrity.

Main Methods:

• Rats were divided into control, low-dose (10 mgF-/kg/day), and high-dose (20 mgF-/kg/day) fluoride groups.
• Fluoride administration lasted for 1, 2, and 3 months.
• Micro CT was used to analyze tibial trabecular bone parameters; serum oxidative stress markers (GPX, SOD, MDA) were measured.

Main Results:

• Fluoride exposure increased dental fluorosis severity, reduced bone volume and connectivity, and widened trabecular space.
• Trabecular thickness decreased initially in the high-dose group but recovered by 3 months.
• Fluoride inhibited glutathione peroxidase (GPX) activity and increased malondialdehyde (MDA) levels, indicating oxidative stress.

Conclusions:

• Excessive fluoride impairs cancellous bone microstructure, characterized by decreased bone volume and connectivity.
• Fluoride exposure induces oxidative stress by inhibiting antioxidant enzymes and increasing lipid peroxidation.
• This study confirms that excessive fluoride damages cancellous bone and disrupts redox balance, contributing to skeletal fluorosis.