Children's reaction to injection using 27 and 30 gauge needles

Objectives: The purpose of the present study was to assess children's reaction and to record their sensation while receiving dental local anesthesia with a 27 and a 30 gauge (G) needle. Methods: Ninety-five children (57 girls and 38 boys) aged 5 to 12 years-old (mean 8.56 ± 1.42 years) participated in the study. Each patient was randomly assigned to receive the injection either with a needle 27 or 30 gauge for the first visit, and the injection with the other needle administered during the second visit. The modified Behavioral Pain Scale suggested by Taddio et al. was used for objective evaluation. Subjective evaluation was performed according to the Wong-Baker FACES Pain Rating Scale (FPS). Pain-behavioral parameters were evaluated by McNemar analysis. Significance was set at p<0.05. Results: Significant more pain was found during mandibular block injection when needle 27G was used. No difference was found between both needles when maxillary buccal infiltration was performed. The distribution of the injections was: 100 maxillary infiltrations (52.6%) and 90 mandibular block injections (47.4%). No significant difference was found in children's objective and subjective ranking when local anesthesia was performed in the first or second visit. No difference in any parameter was found between boys and girls. Conclusions: Children displayed better behavior during injection when they received a mandibular block injection with a needle 30G than they did when the injection was performed with a needle 27G. No difference regarding to pain between both needles was found when receiving maxillary buccal infiltration.