Preemptive analgesia has as its basic principle the administration of analgesics before the onset of painful stimuli, in order to reduce or prevent postoperative pain, but this question is little explored in implantology. Thus, this study was conducted in order to evaluate the clinical efficacy of ibuprofen in pain prevention after unit implant surgery. For this triple-blind, parallel, placebo-controlled and randomized clinical trial, 54 insertion surgeries of unitary implants were performed. Two groups have received two different protocols 1 hour before surgery: Ibuprofen group (IBU) 600 mg of ibuprofen; and (2) placebo group (maize starch). The intensity of the pain was evaluated through the visual analogue scale (VAS) in 6 times (1, 6, 12, 24, 48 and 72 hours after the surgery). Patients were instructed to take 750 mg of paracetamol as rescue medication, if necessary. The occurrence and the intensity of pain were analyzed by means of an analysis of variance ANOVA with repeated measurements using the general linear model procedure. The IBU group had significantly lower VAS scores overall (IBU = 0.30, ± 0.57; placebo = 1.14, ± 1.07; p<0.001) and at all times in the intra, intergroup comparisons and time/group interaction than the placebo group (p<0.001). The use of rescue medication was significantly lower and the postoperative time was longer in the IBU group compared to placebo (p = 0.002). The single use of ibuprofen was found to be significantly superior in reducing pain after unit implant surgery compared to placebo.