Variation in the Expression of Insulin-like Growth Factor-1 in Human Pulp Tissue According to the Root-development Stage

Insulin-like growth factor-1 (IGF-1) plays an important role in cell proliferation and differentiation. It actively participates during odontogenesis and mineralization of dental hard tissues. The purpose of this study is to use a radioimmunoassay (RIA) to determine whether there are differences in the expression of IGF-1 in human pulp from teeth having incomplete or complete root development. Twenty-six pulp samples were obtained from freshly extracted human third molars, half of them from teeth with incomplete root development. All of the samples were processed and labeled using an IGF-1 RIA kit. Results showed IGF-1 presence in all human pulp samples with a statistically significant higher expression in pulps having complete root development. The present findings are consistent with the hypothesis that IGF-1 contributes toward forming and mineralizing dental tissues in teeth with incomplete root development as well as in pulp-repairing process in teeth with complete root development.