By: 28 March 2016
Research reveals a new way to administer anaesthetic in the mouth

Research reveals a new way to administer anaesthetic in the mouth

A study published in Colloids and Surfaces B: Biointerfaces has revealed how the dentist could give patients anaesthetic using a tiny electric current instead of a needle.

Researchers from the University of São Paulo investigated a way of getting topical anaesthetics into the body more effectively, to see if they could replace needles altogether. They found that applying a tiny electric current – a process called iontophoresis – made the anaesthetics more effective.

Anaesthetic hydrogel was first prepared with a polymer to help it stick to the lining of the mouth. The researchers added two anaesthetic drugs, prilocaine hydrochloride (PCL) and lidocaine hydrochloride (LCL), and tested the gel on the mouth lining of a pig, applying a tiny electric current to see if it made the anaesthetic more effective.

The anaesthesia was fast-acting and long-lasting. The electric current made the PCL enter the body more effectively, with a 12-fold increase in the permeation of the anaesthetic agent through the mouth lining.

The new findings could help improve dental procedures and bring relief to millions of people who are scared of needles, say the researchers.

“Needle-free administration could save costs, improve patient compliance, facilitate application and decrease the risks of intoxication and contamination,” explained author Renata Fonseca Vianna Lopez. “This may facilitate access to more effective and safe dental treatments for thousands of people around the world.”

In recent years Lopez’s research group has worked on the development of novel drug delivery systems for the treatment of several skin and eye diseases using nanotechnology, iontophoresis and sonophoresis, which is permeation using sound waves. The researchers now plan to develop an iontophoretic device to use specifically in the mouth and to carry out preclinical trials with the system.

Source: Medical News Today


Cubayachi, C., do Couto, R.O., de Gaitani, C.M., et al. (2015) Needle-free buccal anesthesia using iontophoresis and amino amide salts combined in a mucoadhesive formulation. Colloids and Surfaces B: Biointerfaces. doi: 10.1016/j.colsurfb.2015.11.005