The aim of this study was to evaluate the anesthetic effectiveness of the Anterior Middle Superior Alveolar (AMSA) injection administered through a computer-controlled local anesthetic delivery system (CCLAD), and compare it with the traditional buccal and palatal injections used to anaesthetize maxillary primary molars. Furthermore, an assessment of children's pain reactions and perceptions was carried out, comparing the AMSA injection using the CCLAD to the traditional buccal and palatal injections.