Purpose: This randomised double-blind placebo-controlled trial was carried out to investigate the effect of a one-week post-operative course of 600 mg of ibuprofen taken four times a day on marginal bone level around dental implants. Materials and methods: A total of 61 patients were allocated to the ibuprofen (31 patients) or placebo group (30 patients). Overall, 132 implants were inserted, 67 implants in the ibuprofen group and 65 implants in the placebo group. Preparation of the implant sites was carried out with an intermittent drilling sequence adapted to the fixture diameter and the local bone quality according to the Astra Tech implant installation guide. The primary outcome measure was the change in marginal bone level around dental implants from the baseline (2 weeks post-placement) to the 3- and 6-month radiographic examinations. The paralleling technique and a film holder coupled to a beamaiming device were used to take the periapical radiographs. Measurement of changes in bone level was made using a viewing box and ×8 magnifier. Results: Two patients from the ibuprofen group were unable to complete the prescribed course of ibuprofen owing to a minor self-reported stomach upset. A patient from the control group did not attend any of the scheduled appointments following implant placement. A total of three patients dropped out. All implants survived in either group during the 6-month observation period. The mean marginal bone level changes from the baseline were (-0.33 mm) at the 3-month and (-0.29 mm) at the 6-month follow-up for the ibuprofen group while the corresponding values for the placebo group were (-0.12 mm) and (-0.30 mm). There were no statistically significant differences between groups for mean marginal bone level changes at 3 months (P = 0.27) or 6 months (P = 0.97). Conclusions: Administration of a short course of systemic ibuprofen for post-operative pain management subsequent to implant placement may not have a significant effect on the marginal bone around dental implants in the early healing period. Keywords: dental implants, ibuprofen, marginal bone, periapical radiograph, placebo