Thermal Vision Examination of Vasoconstriction and Vasodilatation of Blood Vessels under the Influence of Local Anesthetic Solutions

A quality local anesthesia is one of the imperatives of performing dental interventions, and especially oral-surgical interventions, where the success of the oral-surgical intervention is seen through the success of local anesthesia. There is a high number of different local anesthetic solutions (LAS) on the market, holding different levels of vasoconstrictors which are attributed with causing numerous complications during the local anesthesia. The aim of this research is to point out the temperature changes caused by different LAS, depending on the strength and the concentration of LAS, using thermal vision camera. Testing was performed on 70 experimental Wistar rats, aged 4.5 months, with an average weight of 250 grams, male, and divided into seven groups of 10 animals each, depending on the applied anesthetic. After injecting the anesthetic solution into the haunch area, a stopwatch was turned on and control measurements were conducted for a period of two hours. All footage from the thermal camera was later transferred to a computer unit. Occurrence of multiple temperatures in the rats’ examined regions, compared to the control region, was noticed only when applying 2% pure lidocaine (without vasoconstrictors). The highest temperature drop, compared to the control region, was noticed with 2% mepivacaine with adrenaline (1 : 100 000), and 2% mepivacaine with noradrenaline (1 : 100 000), fi ve minutes after applying the local anesthetic. In conclusion: vasoconstricting effects are most expressed in the fi fth minute after applying LAS, and there are minimal differences between the effects of adrenaline and noradrenaline, in the examined combinations together with LAS.