Sedation may minimize physiologic and behavioral stress responses. In our facility, the infusion rate of propofol is adjusted according to the bispectral index (BIS) in all cases of implant-related surgery; multivariate analysis of retrospective data enabled us to extract independent factors that affect the dose of propofol in sedation that are considered useful indicators for achieving adequate sedation. The study population comprised all patients undergoing implant-related surgery under intravenous sedation in Okayama University Hospital from April 2009 to March 2013. The infusion rate of propofol was adjusted to maintain the BIS value at 70–80. The outcome was the average infusion rate of propofol, and potential predictor variables were age, sex, body weight, treatment time, and amount of midazolam. Independent variables that affected the average infusion rate of propofol were extracted with multiple regression analysis. One hundred twenty-five subjects were enrolled. In the multiple regression analysis, female sex was shown to be significantly associated with a higher average infusion rate of propofol. Females may require a higher infusion rate of propofol than males to achieve adequate sedation while undergoing implant-related surgery.