EFFECT OF PRE-WARMING OF LOCAL ANESTHESIA ON REDUCING PAIN PERCEPTION DURING INJECTION IN CHILDREN: A RANDOMIZED CONTROLLED CLINICAL TRIAL

Objectives: To evaluate the effectiveness of Pre-warming of LA solution to body temperature(37°C) and (40°C) in pain reduction during injection in contrast to LA at Room Temperature(RT) in both Maxillary Infiltration(MI) and Inferior Alveolar Nerve Block(IANB) techniques.Materials and Methods: The study was a triple blinded randomized controlled clinical trial(RCT)that included 72 children 5-7 years old having at least one primary molar requiring dental treatment. Participants were randomly allocated to three groups according to the temperature of LA; Group I(Control) received LA at RT, Group II received LA pre-warmed to 37°C and Group III received LA pre-warmed to 40°C. Each group was further sub-divided into two sub-groups; (A)and(B) according to the required injection technique. Subgroup(A) received MI and Subgroup(B) received IANB. Pain perception was evaluated physiologically, objectively and subjectively using Heart Rate(HR), Sound, Eye, Motor(SEM)scale and a Maunuksela modified face pain scale(FPS), respectively.Results: 72 children; 35 boys and 37 girls, participated in the study. Pre-warmed groups experienced significantly less pain manifested as significantly lower HR(P=0.04) and SEM(P=0.03) scores compared to RT group. Adjusted mean(SE) for group I, group II and group III regarding HR was 112.79(2.93), 102.33(2.93) and 107.19(2.93) respectively, and regarding SEM was 5.08(0.34), 3.88(0.34) and 3.96(0.34)respectively. There was no significant difference in FPS scores between the three study groups(P>0.05). There was no significant difference between results of MI and IANB sub-groups.Conclusion: Pre-warming of LA provided significantly lower pain perception during LA injection in children compared to LA at RT according to physiologic and objective testing methods.