Chronic Lead Exposure Alters Mineral Properties in Alveolar Bone

Abstract

The objective of the present study was to investigate the effects of chronic lead exposure on the mineral properties of alveolar bone. For this purpose, female Wistar rats (n = 8) were exposed to 1000 ppm lead acetate in drinking water for 90 days, while the control group (n = 5) was treated with sodium acetate. The alveolar bone structure and chemical composition of the dissected mandibles were examined using micro-computed tomography (micro-CT), scanning electron microscopy (SEM), inductively coupled plasma optical emission spectrometry (ICP-OES), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), and X-ray diffraction (XRD) techniques to determine possible alterations in alveolar bone due to lead exposure. In addition, changes in bone mechanical properties were analysed using a three-point bending test. Exposure to lead induced notable changes in bone mineralization and properties, specifically a reduction of the trabecular thickness and bone mineral density. Furthermore, there was a reduction in carbonate content and an increase in bone mineral crystallinity. These changes in bone mineralization could be explained by an alteration in bone turnover due to lead exposure. Three-point bending showed a trend of decreased displacement at failure in the mandibles of lead-exposed rats, which could compromise the mechanical stability and normal development of the dentition.