[Objective assessment of mental nerve local anesthesia]

Area of Science:

• Neuroscience
• Anesthesiology
• Dental Research

Background:

• Conduction anesthesia is crucial in dentistry for pain management.
• Understanding the effects of local anesthetics on specific nerve fibers is essential for optimizing clinical practice.
• Thermal stimuli provide a method to selectively assess A-delta and C-fiber function.

Purpose of the Study:

• To investigate the impact of conduction anesthesia on the mental nerve's response to thermal stimuli.
• To compare the effects of articaine and mepivacaine on thermal evoked potentials (EPs).
• To evaluate the selective blockade of thin nerve fibers by different local anesthetics.

Main Methods:

• A pilot study involving 24 healthy volunteers.
• Administration of 4% articaine with vasoconstrictor or 3% mepivacaine without vasoconstrictor.
• Recording of thermal evoked potentials (thermal EPs) using a Contact Heat Evoked Potential Stimulator (CHEPS) before and after anesthesia.

Main Results:

• Significant decrease in amplitude and elongation of latency for N2-P2 complex components of thermal EPs post-anesthesia.
• Complete disappearance of thermal responses in 58% of participants.
• Total response disappearance occurred in 77% after articaine versus 27% after mepivacaine (p<0.05).

Conclusions:

• Articaine demonstrated a more profound effect on thermal EPs, suggesting deeper anesthesia and potentially greater blockade of thin nerve fibers.
• Mepivacaine without a vasoconstrictor showed a less pronounced effect on thermal EPs.
• Findings suggest differential efficacy of articaine and mepivacaine for specific clinical applications, with articaine potentially better for bone/tooth pain and mepivacaine for soft tissues.