INTRODUCTION• Pain is one of the most common reasons for patients to seek medical attention and one of the most prevalent medical complaints• 9 out of 10 Americans aged 18 or older suffer pain at least once a month, and 42% experience it every day.• Consequently, physicians and other practitioners need education to assist in developing the skills needed to evaluate and manage patients with pain.
PAIN - DEFINITION• The International Association for the Study of Pain (IASP) defines pain as “an unpleasant sensory and emotional experience which we primarily associate with tissue damage or describe in terms of such damage, or both.”• Father of pain - Bonica
Three Hierarchical Levels of Pain• Sensory-Discriminative Component (location, intensity, quality)• Motivation-Affective Component (depression, anxiety)• Cognitive-Evaluation Component (thoughts concerning the cause and significance of the pain )
Types of pain• Nociceptive,• Neuropathic,• Psychogenic,• Mixed, or idiopathic.
PATHOPHYSIOLOGY OF PAIN Descartes in 17th century described PAIN PATHWAY
Pain messages are two-way traffic. Inhibitory effects areachieved through the descending pathways, which reach fromthe conscious brain down to the gates in the subconsciousbrain and the spinal cord.The reason for this is that the gates are places where the flowof pain messages can be controlled or influenced (Wells &Nown 1998).By sending responses back to the periphery, the brain canordered the release of chemicals that have analgesic effects,which can reduces or inhibit pain sensation.Pain generally starts with a physical event; a cut, burn, tear, orbump (Catalano, 1987).
Nociceptive Pain and Its Mechanisms• nociceptive pain occur as a result of the normal activation of the sensory system by noxious stimuli• a process that involves transduction, transmission, modulation and perception.
Tissue injury (activates)primary afferent neurons called nocicep-tors, (with A-delta and C-fibers) These fibers have specific receptors for noxious me-chanical, chemical or thermal stimuli.Transduction – depolarization of peripheral nerve Transmission occur proximally along the spinal cord to higher centres
Neuropathic pain and its mechanism• Neuropathic pain is the label applied to pain syndromes inferred to result from direct injury or dysfunction of the peripheral or central nervous system.• It is frequently described in terms that warrant the descriptor “dysesthetic:” an uncomfortable, unfamiliar sensation such as burning, shock-like or tingling.
Injury to a peripheral nerve axon abnormal nerve morphology.damaged axon may grow multiple nerve sprouts, -form neuromas. These generate spontaneous activityThese areas of increased sensitivity are associated with a change in sodium receptor concentration, and other molecular processes sites of demyelination or nerve fiber injury associated with tenderness and the appearance of Tinel’s sign
Psychological and “Idiopathic” Pain Mechanisms• When reasonable inferences about the sustaining pathophysiology of a pain syndrome cannot be made, and there is no positive evidence that the• etiology is psychiatric, it is best to label the pain as “idiopathic.”• The experience of persistent pain appears to induce disturbances in mood ,impaired coping, and other processes, which in turn, appear to worsen pain and pain-related distress.
• Other patients have premorbid or comorbid psychosocial concerns or psychiatric disorders that are best understood as evolving in parallel to the pain.• patients with personality disorders, substance use disorders, or mood disorders often are best served by primary treatment for the psychiatric problem
Initial Pain Assessment Guidelines• Obtain a detailed history, including• an assessment of the pain characteristics,• impact of the pain on multiple domains (physical, psychosocial, role functioning, work, etc.),• related concerns and comorbidities (other symptoms, psychiatric disorders including substance use disorder, etc.),• prior work-up and working diagnosis,• prior therapies
• Conduct a physical examination, emphasizing the neurological and musculoskeletal examination• Obtain and review past medical records and diagnostic studies• Develop a formulation including 1) working diagnoses for the pain etiology, pain syndrome and inferred pathophysiology, and 2) plan of care including need for additional diagnostic studies and initial treatments for the pain and related concerns
TYPES OF PAIN BY NATUREPain perceptionPain reaction THEORIES OF PAINSpecific theoryPattern theoryGate control theory
Critical Elements of the Pain History• Characteristics of the pain• Prior evaluation of the pain• Prior treatments for the pain• Patient’s perception of impact of the pain on multiple domains• Physical functioning• Mood and psychological well being• Social, familial, and marital well being• Role functioning, including work, social, family• Sleep, energy level• Comprehensive medication history
Characteristics Potential ElementsTemporal Acute, recurrent or persistent, Onset and duration, Course and daily variation, including breakthrough painIntensity(verbal rating or 0-10 numeric Pain “on average” last day or weekscale) Pain “at its worst” last day or week Pain “at its least” last day or week Pain “right now”Topography Focal or multifocal Focal or referred, and specific radiation Superficial or deepQuality Any descriptor (e.g., aching, throbbing, stabbing or burning) Familiar or unfamiliarExacerbating / relieving factors
PAIN CHARACTERISTICSCharacteristics Acute Pain Persistent PainTemporal features Recent onset and expected to Remote, often ill-defined onset; last duration unknown • no longer than days or weeks Differences Between Acute and Persistent PainIntensity Variable VariableAssociated affect Anxiety may be prominent when Irritability or depression pain is severe or cause is unknown; sometimes irritabilityAssociated pain- related Pain behaviors (e.g., moaning, May or may not give anybehaviors rubbing, splinting) may be indication of pain; specific prominent when pain is severe behaviors (e.g., assuming a comfortable position) may occurAssociated features May have signs of sympathetic May or may not have hyperactivity when pain is vegetative signs severe such as: lassitude, anorexia, (e.g., tachycardia, weight loss, insomnia, loss of hypertension, sweating, libido; these signs may be mydriasis) difficult to distinguish from other disease-related effects.
Control of dental painThree phases Pain control before treatment Pain control during a treatment Pain control after a treatment
1) Before treatment• Find out the cause of pain and eliminate itPULPAL PAIN• Deep caries• Thermal changes without protective base• High points in restoration• Traumatic injuries
Managed by,1) Deep caries excavation and use of cements2) Pulp capping procedures in deep cavities3) Protective base should be given in cases of metal restorations4) Before sending the patient after restorative treatment, check for highpoints5) Attent to traumatic injuries and do the needful6) Find the causes of referred pain and treat the cause
2)During the treatmentUse high speed instruments with• H2O coolants witch will reduce heat and pain• Small bur size, as the size of bur increases, heat dissipation increases• Continuous cutting- increased heat generation• Minimal pressure while cutting or with sharp instruments• Condensation pressure, 4-5 pounds• Burnishing and carving to be done after initial setting of material• Polishing should be done in wet medium
Causes of pain after 24 hours of treatment• High speed cutting without coolant Remove restoration and place temporarily sedative dressing and wait till the pain stops and then proceed for permanent restoration• High points Reduce them• Deep cavity restored with amalgam without a base Remove the restoration and place base, varnish• **If pain persist then do pharmacological treatment
Methods of pain controlA. Local or regional anaesthesia1. Topical anaesthesia2. Local infiltration3. Field block anaesthesia4. Nerve block5. Intraligamentary6. Crestal anaesthetic technique(CAT)
B. Electronic anaesthesia• Trans cutaneous electronic nerve stimulation (TENS)• Based upon gate control theory
C. Audio analgesia• White noise• Principle- stimulus distraction
D. Inhalational anaesthesia• Conscious sedation• N2O + O2