Basics of pain research Abhishek Kumar and Lilja K. Dagsdóttir (PhD Scholars) Section of Clinical Oral Physiology Department of Dentistry, Aarhus University, Vennelyst Boulevard 9 Aarhus, Denmark

What is pain?  Pain is an unpleasant sensory and emotional experience associated with actual or potential tissue damage, or described in terms of such damage *  Warning signal of tissue damage  Classified broadly into acute and chronic pain * International Association for the Study of Pain

Basic mechanisum of pain  Nociceptors : Specialised sensory receptors to detect noxious stimuli.  Spinal chord  Primary afferent fibres: carry noxious sensory information  Ascending pathway: carry nociceptive signals to higher centers in the brain  Brain: primary and secondary somatosensory cortex

 The experience of pain is complex and subjective, and is affected by factors such as cognition (e.g., distraction or catastrophizing), mood, beliefs and genetics Perception of pain

 Sensory organ for receiving inputs  The brain assimilates and organizes the sensory inputs Multisensory inputs

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Pain in Laboratory

Experiment  Demonstrate how pain or perception of pain would affect function Overall Assumption  Craniofacial pain (CFP) and its effects on biting is a model for understanding acute/chronic pain in general  Pain will (may be) decrease the motor functions

Objective  To study the effect of pain in the masseter muscle and Temporomandibular Joint (TMJ) on biting ability / bite force  Sixteen healthy volunteers  Two sessions separated by 3-4 days  Experimental pain

Methods Biteforce

Results

Pain perception

Conclusion  Pain did not affect bite force  Individual’s reaction to pain would be dependent on the ability of the individual to cope with the painful stimulus,  Not pain in itself but rather how pain is perceived

Section of clinical oral physiology

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