Local Anaesthesia

Local Anesthesia Topical, Patch, Infiltration, Block

PAIN CONTROL FACTORS ❂

High pain Threshold • Hypo-reactive » Low reaction to pain

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Low Pain Threshold • Hyper-reactive » High reaction to pain

Pain Reaction Depends On: ❂ ❂ ❂ ❂ ❂ ❂

Emotional State Degree of fatigue Apprehension Gender Fear Age

Local Anesthesia ❂

A drug which upon contact with nervous

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tissue renders that tissue incapable of

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transmitting an impulse on stimulation.

How Nerve Fibers Transmit Painful Stimuli ❂

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NF extension of single cell, nucleus is brain NF is in periphery of body & responsible for receiving initial pain Pain stimulus irritates nerve ending Creates series changes

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Stimulus reproduces itself Stimulus called impulse at this point Impulse proceeds along nerve Continuation of impulse called conduction Brain recognizes pain

How Local Anesthetics Work Theory : Transmission of impulse along nerve caused by alteration in nerve membrane and LA agents alter integrity factor ❂ Raises threshold for excitation of nerve ❂ Anesthetic must come in direct contact with nerve tissues ❂

How Local Anesthetics Work ❂

Motor nerves require higher concentration of anesthetic to cause blockade than do sensory nerves.

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Small fibers blocked earlier than large fibers.

How Local Anesthetics Work ❂

Pain fibers anesthetized before those for temperature and touch.

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The return of function

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in these fibers in in

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reverse order.

Chemical Composition ❂

Esters of aminobenzoic acid

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Non-ester types

• Novocaine

• Xylocaine

• Monocaine

• Dynacaine

• Pontocaine

• Carbocaine

• Primacaine

• Citanest Forte

Chemical Composition ❂

Clinical significance is not the difference

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in chemical composition

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but

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in allergic potential.

Purpose of Vasoconstrictors Reduces blood flow through injected area so that rate of disappearance of local anesthetic from tissues is reduced. ❂ This results in prolonged anesthesia and lesser amount or concentration of LA to produce desired results. ❂ Decrease incidence of toxicity of drug. Toxicity depends amount in bloodstream. ❂

Vasoconstrictors Commonly used in dentistry is ❂ Epinephrine--1 : 50,000 to 1 : 200,000 ❂

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Norepinephrine--1:30,000

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Neo-Synephrine--1:2,500

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Neo-Cobefrin--1:20,000

Two Basic Types of Injection ❂

Nerve Block: Place LA adjacent to main nerve bundle so it will produce anesthetized area covered by distribution of the affected nerve

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Infiltration: Main nerve bundle not accessible OR reason to anesthetize entire area--agent can be deposited in area where pain emanatesonly nerve in local area affected

Block Anesthesia ❂

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Bone of mandible dense Deposit solution near nerve Nerve close to artery and vein Injecting into vessel can complicate procedure

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Blood in anesthetic carpule indicates vessel punctured by needle DDS must aspirate before injection May take 20 minutes for full effect

Block Anesthesia Effects ❂

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Produces numbness and tingling of lip Lip feels large and swollen Tip and side of tongue will tingle and become numb Numbs only one side of tongue

Areas of Anesthesia & Technique Mand ibu lar ( Inf er ior Alveol ar ) Nerv e B loc k supplies mandibular teeth is the inferior alveolar-- can be blocked at entrance to mandible at inferior alveolar foramen ❂ Numbness & tingling of lip, anesth of teeth,buccal gingiva from midline to 1st PM,possible anesth of tongue same side ❂

Areas of Anesthesia & Technique Ling ua l Nerv e B lo ck - Branch of mandibular nerve which lies medial to inferior alveolar nerve in area of inferior alveolar foramen ❂ Produces numbness of lateral border of tongue on same side, anterior two thirds tongue, floor of mouth same side ❂

Areas of Anesthesia & Technique ❂

Lo ng B uc ca l Ner ve Inject io n - nerve lies within gingiva of 2nd & 3rd molars on buccal side of mandible

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Performed by few drops placed in tissue

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Will anesth buccal gingiva from 1st premolar to distal of 3rd molar area

Areas of Anesthesia & Technique Me ntal Ner ve B lock - object of block is to interfere with nerve conduction along mental nerve by placing anesth in mental foramen -- seldom used ❂ Produces numbness of central and lateral incisors, canine, and 1st premolar and gingiva, lip, chin area ❂

Areas of Anesthesia & Technique Pos teri or Superio r Al veolar Inj ect io n - PSA ❂ Supplies innervation to maxillary sinus and molar teeth, with exception of mesial buccal root of first molar second buccal gingiva around molar teeth ❂ Site is height of mucobuccal fold apex of max 2nd molar,distal to zygomatic process of maxilla ❂

Areas of Anesthesia & Technique Mi dd le Superi or A lveol ar I nject ion ❂ MSA block ❂

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Nerve supplies premolar teeth and the mesial buccal root of the first molar

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Site over apex of 1st premolar

Areas of Anesthesia & Technique ❂

Anterior Sup erior Alve ola r Inj ect io n -

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Nerve supplies the incisors and canines

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Given slightly mesial to apex of canine bilateral to anesth six anterior teeth

Areas of Anesthesia & Technique ❂

Mi dd le Superi or A lveol ar I nject ion :

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Nerve supplies premolar teeth and mesial buccal root of 1st molar

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Site over apex of 1st premolar

Areas of Anesthesia & Technique ❂

Anterior Sup erior Alve ola r Inj ect io n :

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Nerve supplies incisors and canines

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Site slightly mesial to apex of caninebilateral six anterior teeth

Areas of Anesthesia & Technique Grea ter P alat ine (Ant erior ) Inj ect io n : Nerve supplies mucosa of hard palate opposite molar and premolar teeth ❂ Site opposite 2nd molar about 1 cm toward midline of palate-greater palatine nerve ❂ Usually used forsurgical procedures because palatal gingiva attaches to teethwill numb palatal area opposite M & PM ❂

Anesthesia & Techniques Na sopal at ine Ner ve Inject ion : Nerve emerges from nasopalatine (incisive) canal to supply mucosa of palate opposite incisors and canines ❂ Site is nasopalatine foramen- few drops only ❂ Anesthetizes palatal mucosa opposite six anterior teeth ❂

Reactions to Local Anesthesia ❂

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Syncopy

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Loss of blood flowfainting-psychoTrendelburg position

Toxic

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High level of drug in circulation-agitationrestless-HR& BP upthen CNS depressionnonester have depression only

Reactions to Local Anesthesia ❂

Allergic

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Immediate- target lungs and circulatory Delayed-minor typehours to days after IM or IV or oral antihistaminesBenadryl 50 mg eitherIM or PO Document patient chart

Complications of Injections ❂

Injury to nerve • Inferior alveolar block • Burning sensation lip

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Blanching of skin • spasm, time heals

Broken needle • Infrequent,removal

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Injury to blood vessels • Torn vessel-hematoma • warm rinse/warm compress reduce swelling

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Infections • previously used needle • passage of needle thru infected area

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Idiosyncrasy • unknown reaction

Anesthetics Used In CCSU Clinic ❂

Carbocaine 2% with Neo-Cobefrin • • • •

mepivacaine hydrochloride and levonordefrin 1:20,000 No epinephrine Use for hypertensive patients

Anesthetics Used In CCSU Clinic ❂

Octocaine 100 • Lidocaine HCI 2% and Epinephrine 1:100,000

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2% Xylocaine • Lidocaine HCI and epinephrine 1:100,000

Indications for Use ❂

Dental Hygiene • Scaling and root planing in deep periodontal pockets • Gingival curettage • Extreme cases of soft tissue inflammation and discomfort • Instrumentation of extremely hypersensitive teeth

Correct Documentation ❂

ALWAYS enter on procedures any anesthesia used on patient • 2% lidocaine1:100,000 epi 2 cc (Dr. Lemons) RSP UR

Preparation for Local Anesthesia ❂ ❂ ❂ ❂ ❂ ❂ ❂

Sterile 2X2 gauze cotton tip applicator topical anesthetic aspirating syringe needle stick shield anesthetic carpules

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Long: mandible block Short: maxilla & mandible infiltration Gauge: larger number means smaller diameter of needle • eg. 27, 30

Procedure for Local Anesthesia ❂

See CCSU Clinic Manual

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Section 5.12

Transoral Delivery Anesthesia Dentipatch ❂ 2 cm patch contains Lidocaine ❂ Acts on INTACT mucosa to produce local anesthesia ❂ Anesthesia occurs within 2.5 minutes of application and can last up to -present for 15 minute application period and 30 minutes after removal ❂

Transoral Delivery Anesthesia Has one fifth level of intravenous dose ❂ Not for pregnant individual/nursing/child ❂ Reactions: rare, mild, taste perversion,stomatitis,erythema,mucosal reactions ❂ Gently dry area-remove clear protective liner- allow patch to remain in place-no longer than 15 minutes ❂

Topical Anesthesia 20% Benzocaine in a water soluble base ❂ Can be liquid or gel ❂ Fast action ❂ Short duration ❂ Virtually no systemic absorption ❂ Apply to small area to be anesthetized ❂ Anesthesia accomplished 15 to 30 seconds ❂