The addition of dexmedetomidine (DEX) is a safer option for pain control without the adverse cardiovascular effects of other local anesthetics in dental procedures, according to the Nippon Dental University School of Life Dentistry in Tokyo, Japan.
Researchers there compared the use of the traditional oral pain block, a mixture of articaine and epinephrine, with a mixture of articaine and low-dose DEX. Both epinephrine and DEX would prolong the numbing effects of the articaine.
However, the researchers said, epinephrine can exhibit adverse effects, whereas low-dose DEX would provide a low-toxicity option without the risk of cardiovascular complications.
The researchers used a rat model to examine the duration of a pain block using normal saline (NS), articaine alone (A), articaine in combination with epinephrine (EA), or articaine in combination with DEX (DA).
Forty-four rats were evenly distributed into four groups and were exposed to high heat on one of their paws. After 5 minutes, their paw was injected with one of the pain blocks, and their pain level was assessed at 5-minute intervals to test the duration of effectiveness from 0 to 40 minutes.
The researchers found no significant change in the duration of the NS solution. The rats did have an increase in effective duration when given the A, EA, and DA solutions. The A solution alone had an overall lasting effect of about 20 minutes, while the EA and DA solutions lasted up to 40 minutes.
This shows that with the addition of DEX, the researchers said, the effectiveness of the articaine pain block is similar in duration to that of the traditional articaine plus epinephrine solution. This finding is extremely important because the addition of low-dose DEX has no effect on blood pressure or heart rate, the researchers added, which are adverse effects seen with epinephrine.
The researchers in this study have identified the combination of DEX and articaine to be a potentially safer combination for a pain-blocking solution than the traditional articaine and epinephrine. They suggest further investigations to determine the effectiveness at longer time intervals as well as testing the sedative effects of DEX.
The study, “Adding Dexmedetomidine to Articaine Increases the Latency of Thermal Antinociception in Rats,” was published by Anesthesia Progress.