Effects on human maximum bite force of biting on a softer or harder object

Area of Science:

• Biomedical Engineering
• Neuroscience
• Dental Research

Background:

• Human incisor teeth may possess mechanoreceptors within their pulps.
• These receptors are hypothesized to regulate protective reflexes limiting maximum bite force.
• Previous research suggests pulpal receptors enable detection of surface hardness differences.

Purpose of the Study:

• To investigate the role of pulpal mechanoreceptors in modulating maximum bite force.
• To determine if these mechanoreceptors contribute to conscious perception of surface hardness.
• To test the hypothesis that mechanoreceptors in human incisor pulps influence bite force based on surface properties.

Main Methods:

• Experiments were conducted on 15 participants to measure maximum bite force.
• Participants incised on surfaces of varying hardness (rubber vs. acrylic).
• Some participants had teeth fitted with acrylic crowns to alter stress distribution.

Main Results:

• Maximum bite force was significantly higher when incising on a soft rubber surface compared to a hard acrylic surface.
• This difference was diminished when teeth were covered with acrylic crowns.
• Results align with predictions based on stress distribution and pulpal mechanoreceptor function.

Conclusions:

• The findings support the hypothesis that human incisor pulps contain high-threshold mechanoreceptors.
• These pulpal mechanoreceptors play a role in both subconscious bite force limitation and conscious hardness detection.
• The study elucidates a protective mechanism involving sensory feedback from the tooth pulp.