Local Anesthesia in Dentistry

Wang Yin Stomatology Department , General Hospital affiliated to Tianjin Medical U

niversity

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Local Anesthesia

• Local anesthesia is a local state of insensibility to pain produced by hypodermic injection, local application, or the instillation of an appropriate chemical compound.

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Local Anesthesia Agent Procaine Lidocaine Dicaine• Remain time 45-60 m 90-120 m 120-150m• Infiltration + +• Concentration topical ____ 2-4% 2% infiltration 0.5-1% 0.25-0.5% 0.1% block 2% 1-2% 0.1-0.2%• Toxicity + ++• Allergic response +

• Maximal 800- 300- 60-

dosage 1000 mg 400 mg 100 mg

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Using of Adrenalin Chloride

With the procaine or lidocaine is combined adrenalin chloride in the proportion of one part in about ten thousand can

Enhances and prolongs the anesthetic effectConstricts the blood vessels of the part, less

ening hemorrhageRetards absorption of the anesthetic

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Kinds of Local Anesthesia

• Refrigeration anesthesia

• Topical anesthesia• Local anesthesia by injection

• infiltration

• soft tissue infiltration

• bony tissue infiltration

• conduction (block)

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Refrigeration Anesthesia• Superficial and transie

nt local anesthesia• Ethyl Chloride• Opening superficial ab

scesses• Extraction of loose tee

th

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Topical Anesthesia

• Solutions applied to the mucosa or skin

• Produce insensibility of terminal nerve endings

• Painless insertion of sharp needles

• Opening superficial abscesses

• Extraction of loose teeth• Anodynes for alveolalgia,

ulcer,wound• Dicaine or Cocaine

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Infiltration Anesthesia (terminal, peripheral anesthsia

)

• The anesthesia solution is injected into the mucous membrane or beneath the skin to paralyze sensory nerve endings.

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Infiltration Anesthesia (terminal, peripheral anesthsia

) • Limit to a small area• Soft tissue• Bony tissue• Occur in 5-10 minutes• Remain for 0.5 hour• Extraction of individual teeth (except lower molor

s)• Minor operations

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Infiltration Anesthesia (submucous anesthsia )

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Infiltration Anesthesia (peridontal membrane anesthsia )

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Infiltration Anesthesia (subperiosteal anesthsia )

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Conduction Anesthesia• When injected in the vicinity

of a nerve trunk, an anesthetic solution penetrates by way of the perineurium into the central nerve substance, inhibiting its conducting function, and thus anesthetizing the entire peripheral areas supplied by the nerve. It is therefore anesthesia produced by elimination of the conductivity of the nerve trunk.

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Conduction Anesthesia

• Bone operations

• Extraction of teeth

• Extensive soft tissue procedures of face

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• Outer nerve loop infraorbital N. superior alveolar N.• Supply

bone and teeth of the upper jaw on one side

mucous membrane of mixillary sinus

buccal periosteum and gum tissue

Conduction Anesthesia in Maxilla

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Conduction Anesthesia in Maxilla

• Inner nerve loop anterior palatine N. nasopalatine N.• Supply

hard palate on one side

soft tissue covering it

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Conduction Anesthesia in Maxilla

• Maxillary tuberosity

• Posterior palatine foramen

• Infraorbital foramen

• Incisive fossa

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Maxillary Tuberosity• Injection here will block the posterior superior

alveolar nerve, which supplies the upper molar and sometimes the premolar teeth.

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Maxillary Tuberosity

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Infraorbital Foramen• Injection at the infraobital foramen blocks the peri

pheral distribution of the infraorbital nerve and the anterior superior dental nerve, producing anesthesia of the teeth, the buccal mucous membrane , and the bone, from the canine to the central incisor.

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Incisive Fossa

• Injection at this point blocks the naso-palatine nerve, and gives anesthesia of the anterior portion of the palate, immediately behind the incisor teeth.

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Posterior Palatine Foramen

• An injection at this point blocks the anterior palatine nerve and produces anesthesia of the hard palate as far forward as the canine tooth.

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Conduction Anesthesia in Mandible

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Conduction Anesthesia in Mandible

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Conduction Anesthesia in Mandible

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• Blocking the inferior alveolar nerve at the mandibular foramen produces anesthesia of the teeth, alveolar process and gum tissue of one-half of the lower jaw, with the exception of an area of gum tissue on the buccal side of the molar teeth,which is partly supplied by the long-buccal nerve, the mucous membrane on the lingual side of the teeth, partly supplied by the lingual nerve, and the anterior portion of the mandible, including the incisor teeth, which is supplied in part by overlapping fibers of the nerve from the opposite side.

Conduction Anesthesia in Mandible

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Conduction Anesthesia in Mandible

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Conduction Anesthesia of Lingual Nerve

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Conduction Anesthesia of Buccal Nerve

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Contraindication of Local Anesthesia

• acute suppurative infections• peridental membrane involvements• young children• neurasthenic, apprehensive ,uncooperative patients• patient’s jaw cannot be opened• hyperthyroidism• idiosyncrasy for procaine• hepatitis• cardiovascular disease

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Complications

• Idiosyncrasy

• Shock and collapse

• Breaking the needle

• Postoperative pain

• Hematoma

• Ecchymosis

• Trismus

• Infections

• Prolonged anesthesia

• Facial paralysis

• Procaine dermatitis

• ......

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CLASS OVER