Serum IGF-1 levels as a clinical tool for optimizing orthodontic treatment timing

BACKGROUND The study aims to associate serum insulin-like growth factor-1 (IGF-1) levels with cervical maturation stages (CS) 3, 4, and 5 on lateral cephalogram in male subjects and to find out peak serum IGF-1 levels among these three stages. METHODS The study was conducted on 45 male subjects who were at skeletal maturation stage CS-3, CS-4, and CS-5. Subjects were selected using simple random sampling technique. Serum IGF-1 levels were estimated from blood samples using chemiluminescence immunoassay (CLIA) method. CS was evaluated using a six-stage method of evaluating the cervical vertebrae. Mean IGF-1 levels between the stages were compared by analysis of variance (ANOVA) test. RESULTS One-way ANOVA showed highly significant differences between all cervical stages with p value<0.01, but post hoc Tukey test showed highly significant differences between CS-4 and CS-5 with p value 0.006. Serum IGF-1 levels showed good association with skeletal age in male subjects; 53.3% of subjects at CS-3, 66.7% subjects at CS-4, and 6.7% subjects at CS-5 showed IGF-1 levels in peak range. CONCLUSIONS Serum IGF levels can be used as an additional tool to optimize orthodontic treatment timing.