Abstract
OBJECTIVES: To evaluate the effects of rs1799750 1G/2G polymorphism of the MMP1 gene and rs1800470 T/C polymorphism of the TGF-ß1 gene on temporomandibular disk displacement and vertical facial development. MATERIALS AND METHODS: Sixty-six individuals were examined radiographically prior to evaluation of the signs/symptoms of temporomandibular disorders according to the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Class II, hyperdivergent individuals with TMD (+) were assigned to Group 1, and individuals with TMD (-) were included in Group 2; while Class I, normodivergent individuals with TMD (-) were included in Group 3. For genetic analysis, oral mucosa swab samples were collected, and genotype analysis was performed. RESULTS: The incidence of 2G alleles in Group 2 (72.7%) was significantly higher than the other groups (P < .05). ANB angle and mean Wits of the 1G/1G genotype of the MMP1 gene were significantly lower than 1G/2G and 2G/2G. Mean Go-Gn of the 1G/1G genotype was significantly higher than that of 1G/2G. The mean SNB of the TGF-β1 TT genotype was significantly higher than TC. The mean Co-Gn of TT was significantly higher than CC. CONCLUSIONS: A relationship was found between the 2G allele of rs1799750 1G/2G polymorphisms of the MMP1 gene and the risk of individuals developing disk displacement. Also, it was found that TGF-ß1 gene rs1800470 29 T/C polymorphisms had a detrimental effect on mandibular development.