The main purpose of this study was to evaluate the dose-dependent anesthetic efficacy of the intraseptal anesthesia (ISA) and periodontal ligament anesthesia (PLA) obtained with different volumes of 4 % articaine and 1:100,000 epinephrine (Ar + Ep) in human mandibular premolars, using a computer-controlled local anesthetic delivery system (CCLADS). The safety profile of Ar + Ep was also studied by investigating the stability of cardiovascular parameters. One hundred and eighty randomly selected healthy volunteers (ASA I) entered the single-blinded study to receive 16 mg + 4 μg, 24 mg + 6 μg, and 32 mg + 8 μg of Ar + Ep, obtained with different volumes (0.4, 0.6, and 0.8 ml, respectively), for the ISA and PLA. Success rate, onset, and duration of profound pulpal anesthesia were evaluated by the electrical pulp tester, while the width of the anesthetic field and duration of soft tissue anesthesia were recorded using the pinprick testing. A monitor was used for the measurement of cardiovascular parameters. A dose-dependent duration of pulpal and soft tissue anesthesia was obtained only by the ISA. Success rate, duration of both pulpal and soft tissue anesthesia, and its width were significantly better in the ISA compared with the PLA. No significant cardiovascular changes were seen in both groups. It can be suggested that 0.6 and 0.8 ml of 4 % Ar + 1:100,000 Ep, delivered by CCLADS, offer high success rate and effective clinical parameters of ISA as a primary anesthesia. It seems that dental procedures requiring profound pulpal, bone, and soft tissue anesthesia could be effectively and safely obtained by mentioned anesthetic protocol.