Dr Rosenberg Biology of Endodontic Pain.pdf

NEW YORK UNIVERSITY COLLEGE OF DENTISTRY PAUL A. ROSENBERG, DDS PROFESSOR DEPARTMENT OF ENDODONTICS 2023 [email protected] ENDODONTIC PAIN Biology of Endodontic Pain Part 1 Review Pathogenesis of a periapical lesion • • How does a carious lesion progress and become a periapical lesion? How would...

NEW YORK UNIVERSITY COLLEGE OF DENTISTRY PAUL A. ROSENBERG, DDS PROFESSOR DEPARTMENT OF ENDODONTICS 2023 [email protected] ENDODONTIC PAIN Biology of Endodontic Pain Part 1 Review Pathogenesis of a periapical lesion • • How does a carious lesion progress and become a periapical lesion? How would we diagnose the radiolucent lesio Important Questions • • • • • • Is the tooth vital or non vital? Significance? How do you determine vitality? Is the patient in pain? What is causing the periapical lesion? What are the most common periapical lesions? Can a non vital tooth cause pain? Appropriate Terminology • Odontogenic lesion • Periapical lesion • Periapical radiolucency • Non–odontogenic lesions Non–endodontic lesions can mimic Endodontic lesions • Most non-odontogenic lesions are found in the mandible • The probability of encountering non–endodontic lesions is 8% • Examples of non-endodontic lesions odontogenic keratocyst (OKC), traumatic bone cyst, ameloblastoma, metastatic lesions Krongbaramee T. J Endo,2023 Only a biopsy can determine precise diagnosis of a periapical lesion Lesions Commonly Associated With Endodontic Pathosis • • • • Periapical Periapical Periapical Periapical granuloma (73%) cyst (21%) abscess(6%) scar (0.4%) Krongbaramee T. J Endo,2023 Review How would you differentiate these lesions? 1. Sensibility tests (vitality tests) 2. If teeth tests vital…biopsy If a tooth in question tests vital the swelling is non odontogenic!!! Periapical Abscess Rhabdomyosarcoma Non vital #7 Allcritical teeth tested Biopsy for vital diagnosis Biology Bacteria in canal The cause of periapical pathosis is intra-canal bacteria Periapical pathosis Granuloma An Area of Dynamic Activity Pain is dependent on multiple factors: patient’s sex, anxiety, clinical factors, genetics, immune system Fouad AF, Kahn AA, Kang MK Frontiers in Physiology 2020;11:1-1 Periapical Abscess Localization of an Infectious Process Cellulitis Represents the host’s inability to localize an infectious process Pain An unpleasant sensory and emotional experience associated with actual or potential tissue damage Treating patients with similar teeth, comparable medical / dental histories, using the same approach, may not result in a common outcome. BASIC PAIN OVERVIEW  TISSUE INJURY…MEDIATOR RELEASE  COMPLEX CHEMICAL AND NEUROLOGIC EVENTS…  STIMULATED NERVE ENDINGS AT THE SITE OF INJURY…  TRANSMISSION OF IMPULSES TO HIGHER CENTERS A SIMPLISTIC VIEW: THE PROCESS… IMPULSE TRANSMISSION VIA PERIPHERAL NERVOUS SYSTEM TO CNS… PROCESSED WITHIN CNS… PERCEIVED AT THE LEVEL OF THE CEREBRAL CORTEX X Zahn C, et al. Dental Nerves: a neglected mediator of pulpitis Internat J of Endodontics 2020 The dental pulp is one of the most densely innervated tissues, including sensory, sympathetic and parasympathetic nerve fibers Pulpal nerves also play a role in regulating pulpal inflammatory response Neurons secrete neurotransmitters, neuropeptides and amino acids contributing to induction, sensitization and maintenance of tooth pain Dental nerves also are important for microcirculatory and immune responses during pulpitis Historical concepts of the nociceptive system Sensation Traditional Hardtravels Wired System Stimulation of Impulse received and periph. pain via spinal cord to appropriate action receptors brain started Gate Control Theory (1965) Regulatory or Modulation at the Not hard-wired, system can undergo modulation dorsal horn level by afferent input “gating” mechanism Plastic Changes ( Neuroplasticity) Changes of peripheral receptors, spinal cord or higher cerebral centers Induced changes may be of short duration, last days, months or be irreversible Neuroplasticity “Some areas of the brain are hard wired, other areas especially in the cerebral cortex such as language, thought,as well as sensory and motor functions) can be rewired as we get older.” “Neuroplacticity refers to the brain’s capacity to create new pathways”. (O.Sachs 2011) Changes in Responses to Stimuli HYPERALGESIA …AN INCREASE IN THE PERCEIVED MAGNITUDE OF A PAINFUL STIMULI Ex. Irrev. pulpitis and response to cold ALLODYNIA …A REDUCTION IN PAIN THRESHOLD SO THAT PREVIOUSLY NON-PAINFUL STIMULI ARE PERCEIVED AS PAINFUL Ex. Severe sensitivity to percussion Preventative vs. Reactive CONCEPT… PAIN IS EASIER TO PREVENT PHARMACOLOGICALLY THEN TO TREAT AFTER NOCICEPTIVE MECHANISMS HAVE BEEN ESTABLISHED A dynamic system • Peripheral and central neuroreceptors are subject to change • Threshold for response can be altered • Pain and inflammation lead to changes in neuronal activity which may prolong pain and can result in chronic pain HOST RESPONSE TO TISSUE DAMAGE Bacterial, Physical and/or chemical injury TISSUE DAMAGE ARACHADONIC ACID MEDIATOR RELEASE Prostaglandins INFLAMMATION Neuronal Events Vascular Events Neuropeptide Release Hageman Factor PAIN Kinin system Fibrin deposition (clotting) Immunological Events Intracellular Signals INNATE ADAPTIVE T Cell Activity Fibrinolysis Resolution Complement System Classic Alternative Lectin Scarring Abscess T 4 (+) T 5 (-) B Cell Activity Cellular Events Macrophage Mast Cells NK Cells PMN’s Complete Healing Leukotrines PGE PGF PGI Cytokines Histamine T cells Acute Inflammation Chronic Necrosis What’s missing from the previous image? Predisposing factors that affect a patient’s variable responses to endodontic procedures. Genetics and Immune system Psychological State Ethnicity Sex Age Environmenta l Factors Comorbidities “…not a level playing field.” Office Environment Pre-Treatment Diagnosis Controllabl e Factors Pain Preventive Strategies Endodontic Procedures and Post Operative Care ANXIETY REDUCTION:  AN IMPORTANT PREOPERATIVE GOAL ANXIETY PAIN THRESHOLD ANXIETY REDUCTION   WHAT DO YOU SAY TO YOUR PATIENTS? ADDRESS CAUSE OF ANXIETY…PAIN OVER 200 STUDIES INDICATE…. “… PRE-EMPTIVE BEHAVIORAL INTERVENTION TO DECREASE ANXIETY BEFORE AND AFTER SURGERY… REDUCES POST OPERATIVE PAIN INTENSITY AND INTAKE OF ANALGESICS AND ACCELERATES RECOVERY …” CARR DB AND GOUDAS LC. ACUTE PAIN THE LANCET 1999 ; 353 : 2051 - 2058 GIBSON HB. PSYCHOLOGY, PAIN AND ANESTHESIA LONDON: CHAPMAN AND HALL, 1994 “HIGH LEVELS OF STRESS , ANXIETY , OR PESSIMISM IN PREOPERATIVE PATIENTS PREDICT POOR OUTCOMES…. INCLUDING SPEED OF WOUND HEALING AND DURATION OF HOSPITAL STAY.” STRATEGY TO PREVENT HYPERALGESIA…BLOCK FORMATION OF INFLAMMATORY MEDIATORS CLINICAL AND PHARMACOLOGICAL STRATEGIES THE PROCESS… TRAUMA…MEDIATOR RELEASE INFLAMMATORY CASCADE AFTER TISSUE INJURY PHOSPHOLIPIDS MAST CELL ARACHIDONIC ACID HISTAMINE BLOOD VESSEL BRADYKININ PLASMA EXTRAVASATION MAST CELL SUBSTANCE P CGRP CYTOKINES HISTAMINE PROSTAGLANDIN E2 NKA PERIPHERAL AFFERENT FIBER TISSUE CELL MEMBRANE DISRUPTION PHOSPHOLIPASES CORTICOSTEROIDS INHIBITION ARACHIDONIC ACID NSAIDS INHIBITION LIPOOXYGENASE PATHWAY CYCLOOXYGENASE PATHWAY (COX) ENDOPEROXIDES HPETE ( Hydroperoxyeicostetraenoic Acid ) PROSTACYCLIN LEUKOTRIENES HETE ( LTC4 ) ( Hydroxyeicosatetraenoic Acid ) THROMBOXANES PROSTAGLANDINS ( PGE, PGF ) PULP PHYSIOLOGY: CIRCULATION NOTE: COLLATERALIZED THIN WALLED VESSELS VASCULAR CHANGES DURING INFLAMMATION INFLAMMATION MARGINATION DIAPEDISIS Consider relationship of pulp to tooth and tooth to bone A unique relationship MEANWHILE… MEDIATORS ARE SENSITIZING PERIPHERAL NERVE ENDINGS (NOCICEPTORS ) MAKING ANESTHESIA MORE DIFFICULT NEGATIVE RESULTS OF INFLAMMATION…     INCREASED INTRA PULPAL PRESSURE INCREASED PERIAPICAL PRESSURE TISSUE DAMAGE PAIN Biological response to operative trauma Reversible or irreversible process? *** INTRAOPERATIVE LOCAL ANESTHETIC CHALLENGES AND STRATEGIES Mandibular molars with irreversible pulpitis pose a challenge associated with achieving profound local anesthesia. Local Anesthesia and Irreversible Pulpitis What is irreversible pulpitis? Irreversible pulpitis is characterized by : • Acute lingering pain following a cold stimuli • Heat may also cause pain • Sensitivity to percussion • Spontaneous pain • These symptoms indicate the pulp is beyond repair without an intervention EFFECT OF INFLAMMATION ON INF. ALVEOLAR NERVE BLOCK 1.8 CC OF LIDOCAINE WITH 1: 100,000 EPI. NORMAL PULP  75-90% EFFECTIVE IRREVERSIBLE PULPITIS  30-80% INEFFECTIVE !!!! HARGREAVES KM AND KEISER K. LOCAL ANESTHETIC FAILURES IN ENDODONTICS ENDODONTIC TOPICS 2002 ; 1: 26-39. …STUDIES INDICATE THAT ANESTHETIC BLOCKS GIVEN TO PATIENTS WITH IRREV. PULPITIS IN A MANDIBULAR TOOTH HAVE , ON AVERAGE……. ONLY A 55% INCIDENCE OF PULPAL ANESTHESIA, EVEN IN THE PRESENCE OF 100% LIP NUMBNESS. HARGREAVES KM AND KEISER K. LOCAL ANESTHETIC FAILURE IN ENDODONTICS ENDODONTIC TOPICS 2002 ;1: 26-39. Other studies… RESULTS OF CLINICAL STUDIES… “… PATIENTS WITH IRREVERSIBLE PULPITIS HAD AN 8 - FOLD HIGHER FAILURE OF LOCAL ANESTHETIC INJECTIONS IN COMPARISON TO NORMAL CONTROL PATIENTS.” Lip Numbness: Soft Tissue vs. Dental Anesthesia Check the Chief Complaint Before Starting! When is your patient ready to start an Endodontic procedure? • Numb lip? • Numb gingiva? • Tingling lip? None of the above !!!! Hsiao-Wu GW et al. Use of the Cold Test as a Measure of Pulpal Anesthesia During Endodontic Therapy JEndod 2007;33:406-410 • Soft tissue signs are inadequate to assess pulpal anesthesia during RCT • Subjects who received a negative response to a cold test were approximately 80% less likely to experience pain during RCT compared to those A numb lip is a poor way to assess profound local anesthesia!!! Use a cold test and/or the chief complaint to assess local anesthesia!!! Endo Ice • Is there a response to application of cotton soaked with Endo Ice spray? IF THE ANSWER IS “YES”, THE PATIENT DOES NO HAVE COMPLETE LOCAL ANESTHESIA!!! If a patient has a numb lip but feels pain on application of cold…  Select a supplemental anesthetic injection: • • • • Infiltration Ligamental Intra-osseous Intra-pulpal Selection is made on a case by case basis Important clinical strategy • If a patient does not have a numb lip… provide an additional mandibular block • If a patient has a profoundly numb lip but still has pain from provocation with the chief complaint , Endo Ice or percussion… provide a supplemental injection “THE HOT TOOTH” Consider the biologic process Wallace JA et al. Clinical Problem of Regionally Anesthetizing the Pulp of an Acutely Inflamed Mandibular Molar. Oral Surg Oral Med Oral Pathol. 1985; 123: 27-34. Will this case pose a problem with anesthesia ? What is the probable biological process… “ Nerves in inflamed tissue have altered thresholds, resting potentials and excitability.” “…A situation in which in spite of the local anesthetic agent, transmission of the impulse does Strategies: Local Anesthesia     Infiltration Nitrous Oxide Oral Sedation Additional Block     Ligamental Intraosseous Intrapulpal IV Sedation* Ligamental Intraosseous Intrapulpal X Birchfield J, and Rosenberg PA. Role of the Anesthetic Solution in Intrapulpal Anesthesia. J Endod 1975;1:26-27 • Intrapupal injections (saline or local anesthetic ) were given in a double blind manner… • Anesthesia produced by the intrapulpal technique was not the result of the anesthetic solution… Pressure seemed to be the key factor. Nitrous Oxide Patient with rubber Dam and nitrous mask