Objective: The technique of local anesthetic administration is an important consideration in the behavior guidance of a pediatric patient. The study hypothesized that there is no difference in the pain effectiveness in the experimental subjects with the use of single tooth anesthesia and the controls with the use of conventional technique (traditional inferior alveolar nerve block [IANB]).The purpose of this study was to compare the anesthesia effectiveness of traditional IANB; IANB using a computer-controlled local anesthetic delivery system (CCLAD); and intraligamental anesthesia (ILA) using CCLAD in pulpotomy of the primary mandibular second molars. Method and Materials: Ninety-one healthy 5- to 9-year-old children underwent pulpotomy of the mandibular second molars. They were randomly assigned into Group A (traditional IANB), Group B (IANB using CCLAD), or Group C (ILA injection using CCLAD). The effectiveness of anesthesia was measured during different steps of pulpotomy using the sounds, eyes, and motor (SEM) scale. The postoperative complications were recorded after 24 hours. Results: For all five pulpotomy steps, the anesthesia effectiveness was similar among the three anesthesia techniques. Anesthesia effectiveness was not significantly different (based on SEM scores) between the three groups during clamp application, drilling of the tooth, entering the pulp, pulp extirpation, and removal of the clamp (P = .635, P = .996, P = .630, P = .945, and P = .101, respectively). There was no significant difference in postoperative complications between the three groups. Conclusion: The IANB anesthesia using CCLAD and periodontal ligament anesthesia using CCLAD were as effective as traditional IANB in anesthetizing the primary mandibular molars during pulpotomy. Keywords: anesthesia, computerized, effectiveness, mandibular, primary molars, pulpotomy