INTRODUCTION:One of the shortcomings of local anesthesia (LA) is that the soft tissue anesthesia (STA) typically lasts for 3 to 5 hours while most routine dental procedures are completed in less than an hour. Pediatric patients particularly may accidently bite on their lips.
OBJECTIVES: The study was conducted to evaluate the effectiveness of phentolamine mesylate (PM) on the reduction of the incidence of self-inflicted soft tissue injury (STI) and its effect on the time of return of normal function, after inferior alveolar nerve block anesthesia.
MATERIALS AND METHODS: The study is a blinded randomized controlled parallel group clinical trial with a 1:1 allocation ratio. A total of eighty pediatric patients, with an age range of 5-8 years, selected from the Pediatric Dentistry out-patient clinic, Faculty of Dentistry, Alexandria University, after obtaining necessary consents. Inferior alveolar nerve block anesthesia (2 percent lidocaine with 1:100,000 epinephrine) was administered in the recommended dose. After completion of the operative procedure, participants were randomly allocated into 2 groups: study and control group. The experimental group received a PM injection using the same technique employed for administration of LA, in a cartridge ratio of 1:1. The control group did not receive any reversal agent. The incidence of self-inflicted STA and return to normal function were recorded post-operatively and STI was followed up after 24 hours.
RESULTS: There were no significant differences in the incidence of self-inflicted STI between the PM and control group except for the occurrence of ulcers after 24 hours (P=0.04). Phentolamine mesylate accelerated the median time of return to normal function (P =0.001).
CONCLUSION: Phentolamine mesylate was efficacious in reducing the incidence of self-inflicted soft-tissue ulceration and accelerated the time of return to normal function after LA.