STENCILDENT

  LOCAL ANAESTHETICS Drugs that block peripheral nervous tissue when applied locally to nerve tissue in appropriate concentration,without loss of consciousness CLASSIFICATION: A) INJECTABLE : SHORT ACTING : Procaine  Chloroprocaine  INTERMEDIATE ACTING  Lignocaine  Prilocaine LONG ACTING Bupivacaine  Ropivacaine tetracaine  B) SURFACE ANAESTHETIC: Lignocaine  Cocaine Tetracaine MECHANISM OF ACTION : Primary mechanism of action: blockade of voltage gated sodium channel  local anaesthesia diffuse through cell membrane to bind the voltage sensitive sodium channel to prevent generation of action potential and conduction  DIFFERENTIAL BLOCKADE: 1)Autonomic (1st blocked )followed by sensory fibres,pain temperature ,touch ,pressure,vibration  Non myelinated fibres are blocked readily than myelinated  FEATURES OF LOCAL ANAESTHETICS: 1) It should have quick onset of action  2)It should not be irritating to skin and mucous membrane  3)Duration of action must be long enough to allow desired surge

  ORAL SUBMUCOUS FIBROSIS DEFINITION SIRSAT AND PINDBORGS : An insidious chronic disease affecting any part of oral cavity and sometimes pharynx,occasionally preceded by /associated with vesicle formation and always associated with juxta epithelial inflammatory reaction followed by hyalinisation of lamina propria with epithelial atrophy leading to stiffness of oral mucosa and progressive limitation in mouth opening In 1952,SG JOSHI coined the term oral submucous fibrosis  ETIOLOGY: Arecanut Chilli Genetic Autoimmunity  Composition of arecanut :alkaloid,flavonoid  predisposing factors :Nutritional deficiency  RATE OF INCIDENCE: 1984  - 4.5% 1990 - 7.6% 2000  - 13.33% PATHOGENESIS: Oral mucosa Betel quid habit  Constant irritation Chronic inflammation Activated t-cell and macrophage at the site  Transforming growth factor : Increases collagen production,Decreases collagen degradation Increased collagen production  FIBROSIS  Increase in cytokines (interleukin-6,interferon gamma,tumour nec

  CATECHOLAMINES Neurotransmitter that take part in adrenergic transmission Catecholamines are synthesised from adrenal medulla ,from a specialised cell:chromaffin cell  The catecholamine includes : Adrenaline Nor -adrenaline Dopamine SYNTHESIS : 1)AT BLOOD : Phenylalanine