Using a one-stage surgical protocol, a total of 34 Branemark Mk-III Ti-Unite implants with a length of 13 mm and a diameter of 3.75 mm were inserted in 10 edentulous mandibles. Of these, seven patients received four and three patients two interforaminal implants. All implants were followed with repeated stability measurements by means of resonance frequency analysis at different time interval: 0, 4, 8, 12, 16, 20, 24, 28, 32, 36, 40, 44 days. In quadrant III platelet-rich plasma (PRP) was instilled locally before implant placement, while no PRP was added in quadrant IV to serve as control group (split-mouth design). Results showed no statistically significant difference between the two groups. Nonetheless, both groups (PRP+control) showed a highly significant reduction of the implant stability quotient (P < 0.001) between days 0 and 4. However, no difference was noted between the two groups after day 4, it may be concluded that the instillation of PRP during implant placement in the lower anterior mandible did not add additional benefit.