Effect of Heated Local Anesthetic on Pain Perception upon Oral injection

Background and aim: Pain during injection of local anesthesia causes fear and anxiety in many patients that could be a reason why patients avoid regular dental treatment. Previous studies have reported the effect of warming anesthetic solutions in various areas such as skin, plastic surgery, and cataract surgery. The purpose of this study was to evaluate the effect of warming anesthetic solution on the control of pain perception during maxillary infiltration in same patient erffering to faculty of Dentistry, Tehran Medical Sciences of Islamic Azad University at 2018. Material and Method: This research was based on clinical trial,split mouth type. The patients with indication of anesthesia injection for both sides of maxilla which were agreed to participation of this study, considered as study samples.  2 percent Lidocaine (Daroopakhsh-Iran) was heated by (Tommee-Teppee-England) boiler to 40°C and the injection was performed at 37°C in the experimental group, whereas the opposite side, as the control, served 21°C (room temperature) injection. Either side of maxilla was conducted randomly as experimental group (warm injection) and control group (room temperature injection). The intensity of pain perceived during the injection was assessed by 100 mm Visual Analog Scale and statistically analyzed by the MANN-U-WHITNEY test. Results: Evaluation was made on 16 patients and regarding to type of study, 32 sides. Of samples, 7 male and 13 females were present and age average of them was 36.1±12.98 years old. VAS scores in the control group (room temperature injection) was 38.5±28.5 and in the experimental group (warm injection) was 27.5±20.9. Pain perception was 75% in the control group and 25% in the experimental group (P <0.01). Conclusion: Warming local anesthetic solution prior to injection can efficiently reduce the pain compared to its use at room temperature.