Background/Aim. Bupivacaine (Marcaine®), homologue of mepivacaine, chemically related to lidocaine, is used as a local anesthetic for local infiltration, peripheral nerve block, retrobulbar block, symphathetic block, and caudal and epidural anesthesia. The aim of this investigation was to determine and to compare clinical parameters of the local anesthetic effects of bupivacaine applied with and without a vasoconstrictor. Methods. This investigation included a total of 30 randomly selected patients, who ranged in age from 30−60 years, with partial or total anodontia in the molar region of the mandible. These patients with total or partial edentulous molar part of the mandible, scheduled for dental implantation placement, were asked to participate in the study. In the first phase of the investigation, the patients were subjected to local anesthesia with 3.5 cm3 of 0.5% bupivacaine with a vasoconstrictor (adrenalin, 1: 200 000) in the right side of the mandible. After administering local anesthesia, the placement of blade, cylindrical, transdental (B.C.T.) implants was performed. In the second stage of the investigation, in 7−10 days period after the first oral surgery, the patients were subjected to local anesthesia with 3.5 cm3 of 0.5% bupivacaine, but without a vasoconstrictor, in the left side of the mandible. After administering local anesthesia, the placement of B.C.T. implants was performed. During the performance of both oral surgery procedures, the following clinical parameters of the local anesthetic effects were monitored: latent period, duration and the potency of anesthesia, and the evaluation of the postoperative pain level. Results. The latent period under local anesthesia with 3.5 cm3 of 0.5% bupivacaine and vasoconstrictor was statistically significantly shorter than without vasoconstrictor. The duration of local anesthesia was longer without vasoconstrictor. There was no difference in the potency of anesthesia with or without a vasoconstrictor, while the lowest level of postoperative pain was found after administering bupivacaine without a vasoconstrictor use. Conclusion. The results of this investigation show that bupivacaine without a vasoconstrictor is efficient when used for local anesthesia in placing dental implants since it provides better blood circulation required for good dental implant osseointegration. .