The study evaluated duration and depth of the local infiltration anesthesia by articaine with different combinations of epinephrine and clonidine : articaine (4%) + epinephrine (1: 200 000), articaine (4%) + clonidine (1:100 000), articaine (4%) + epinephrine (1:200 000) + clonidine (1:100 000), articaine (4%) + epinephrine (1: 400 000) + clonidine (1:100, 000) in pediatric dental practice. It was revealed that the replacement of the vasoconstrictor epinephrine on clonidine associated with reduced depth and duration of analgesia. This increased efficiency is provided by inclusion of epinephrine (1:200 000), and clonidine (1:100 000) into anesthetic solution, which provided statistically significant increase in depth and duration of anesthesia.