Kaplan-Meier analysis of failure of the initially installed orthodontic mini-implant (OMI) according to sex. Duration of survival was measured from OMI placement to the time of failure (complete) or to the last follow-up or completion of treatment (censored). Cumulative survival for OMIs in females (group 1, blue) was significantly longer than for those in males (group 2, green) (P = .018; log-rank test)