A comparison of warmed and room-temperature anesthetic for local anesthesia in children.

PURPOSE: The purpose of this study was to assess children's reactions and record their sensations while receiving a warmed local anesthetic solution for dental procedures (37 degrees C; W) compared with one at room temperature (21 degrees C; RT). METHODS: Forty-four children between the ages of 6 to 11 (mean age = 7.9 +/- 2.2 years) who were undergoing dental treatment participated in the study. A random crossover design was used. Each patient was randomly assigned to receive either a W or a RT local anesthesia on the first visit and the alternate local anesthesia on the second visit. During the injection, the modified Behavioral Pain Scale (BPS) was used. For subjective evaluation, the Wong-Baker FACES Pain Rating Scale (FPS) and the Visual Analogue Scale (VAS) were used. RESULTS: No significant difference was found between the W or RT local anesthesia when used during the first or second visit. In all parameters, children's reactions to both types of injection were similar, with no statistically significant difference. Using the FPS, 19 boys (91%) ranked the experience of local anesthesia as a positive experience (0 to 2 in the scale) while 4 boys (9%) ranked the same experience as negative. This was true for both types (W and RT). All 21 girls who participated in the study ranked the local anesthesia experience using the FPS as a positive experience (0 to 2 in the scale). No significant difference was found in the mean VAS scores between the room-temperature group and the warm group (23.4 +/- 21.8 and 20.8 +/- 18.9, respectively). CONCLUSIONS: There is no advantage to warming local anesthetic solution prior to injection.