Single Nucleotide Polymorphisms and Haplotypes in Vascular Endothelial Growth Factor Gene and Residual Ridge Resorption of Mandible in Korean Population

Abstract

The tooth extraction is a routine surgical procedure in the dental treatment where the healing process results in a saddle-shaped residual ridge in the edentulous jaw. There are substantial differences among individuals in the end result. In some cases, there is excessive bone atrophy, which complicates the dental restorative treatment. The alveolar ridge receives the mechanical load continuously from the periodontal ligament connected to the teeth and it diminishes dramatically as a consequence of dental extraction; thus it is believed the continuing pattern of the alveolar bone resorption is related to this change. The reduced partial pressure of oxygen is the most prominent event from the reduced mechanical load. Vascular Endothelial Growth Factor (VEGF), regulated by HIF-1, reported close association with angiogenesis and bone turn over, where partial oxygen pressure has changed. Therefore the genetic association between Single Nucleotide Polymorphsim (SNP) of VEGF gene and RRR was investigated. 120 subjects (70.93 ± 9.28 years) which were treated at Dental clinic of Yonsei University with edentulous mandible were recruited. Mandibular bone height was measured following the protocol of the American College of Prosthodontists. Three variants, rs1570360, rs25648, and rs3025039 in VEGF from previous study, were used as tag-SNPs and genotyping for the study. Student’s t-test and ANOVA were used for statistical analysis. There was a notable association with rs1570360 (P = 0.051) in dominant group and haplotype A-C-C showed a statistically significant association with RRR in dominant group (P = 0.042). Results of this study may be useful in developing novel genetic diagnostic tests and identifying Koreans susceptible to developing severe RRR after dental extraction.