Evaluation of Acceptance, Preference and Efficacy of a Novel Microneedle-Based Dental Anaesthesia System

Objectives:
In current dental practice, local anaesthesia is delivered using the traditional needle and syringe injection method. However, the appearance of long needles and pain associated with it often lead to anxiety and phobia. This often deters patients from dental visits, contributing to an increasing oral disease burden. As a painless and efficient alternative, our team has developed a novel conductive microneedle (MN) patch that is used in combination with iontophoresis (ITP) to achieve deep drug penetration through the oral mucosa and the underlying bone tissue to target the sensory nerves supplying teeth.
Methods: The dual composition of a hydrogel-forming polymer and a conductive polymer allows the MN tips to swell upon contact with mucosal interstitial fluid while significantly lowering the mucosal tissue resistance. Put together, thesetwo key unique properties of the conductive MN array results in a synergistic enhancement of the ITP effect; further accelerating drug flow from the mucosa to the nerves in the alveolar bone that supply sensation to the teeth.
Results: As a proof-of-concept, we show almost immediate dental anaesthetic effect in a clinically relevant rabbit model when EMLA, a commercially existing anaesthetic cream is delivered. A preliminary clinical study conducted on healthy volunteers also showed that 60% of the participants indicated a preference to our innovation in comparison tothe conventional method.
Promisingly, no pain was reported during MN application. It is also notable that 90% of the study participants experienced only comfortable to moderate sensations during ITP.
Conclusions: We demonstrate the successful development of a novel technology that is potentially as effective as the gold standard to achieve equivalent anesthetic delivery efficacywith an added advantage of being a truly pain-free and patient friendly solution. If successfully translated, this innovation is expected to promote patient compliance in seeking timely dental treatments, hence improving clinic efficiency that can translate to overall cost-savings.