Effects of formaldehyde on VEGF, MMP2, and Osteonectin levels in periodontal membrane and alveolar bone in the rats.

BACKGROUND: The objective of this study was to investigate if long term formaldehyde inhalation may effect periodontal membrane and alveolar bone loss leading to periodontitis. the negative effects of formaldehyde was described using vascular endothelial growth factor (VEGF), matrix metallopeptidase 2 (MMP2) and Osteonectin antibodies involved in the extracellular matrix and angiogenetic development.

MATERIALS AND METHODS: Thirty adult Wistar albino rats were used in this study. Rats were divided into two groups, control (n:15) and formaldehyde administered group (n:15). Formaldehyde group was administered 10 ppm formaldehyde during 5 days a week for 8 hours by inhalation. Maxillary bone regions were dissected under anesthesia. After fixation in 10% formaldehyde solution, tissues were passed through graded ethanol series to obtain paraffin blocks. Five-micrometer histological sections were cut with RM2265 rotary microtome stained with Masson- Trichrome and VEGF, MMP2 and Osteonectin antibodies for -examination under Olympus BH-2 light microscopy.

RESULTS: The present study revealed that congestion in blood vessels, degeneration of collagen fibers and alveolar matrix around alveolar bone were observed to be more significant in formaldehyde group than the control group (P≤0.001 ). Interestingly, VEGF expression in the formaldehyde group was the most significant finding between the two groups (P<0.001). When compared inflammation, MMP2 and osteonectin expressions were significant (P<0.01) in the formaldehyde group.

CONCLUSIONS: It was suggested that formaldehyde toxicity decreased the expression of MMP2 and in osteoblasts as well as affecting the retention of MMP levels in tooth cavity, which is very low in collagen fibers. But, vise versa for the expression of VEGF in dilated vascular endothelial cells and osteocytes in alveolar bone. As a conclusion,formaldehyde disrupts the periodontal membrane and may cause collagen fibers degeneration by affecting the alveolar bone matrix.