Matt Fisher, DMD, MS Albuquerque HIS Dental Clinic June 5, 2013

Local Anesthesia  The temporary loss of sensation, including pain, produced by a topically-applied or injected agent without depressing the level of consciousness

Local Anesthesia in Children  Prevention of pain during the dental appointment should reduce fear and anxiety, and promote a positive dental attitude  Attempting to get by without using local anesthesia, when it is needed, is a common mistake by the apprehensive dentist trying to avoid confrontation with an equally apprehensive child

Local Anesthetics  Two general types:  Esters  Procaine (Novocaine®)  Benzocaine  Tetracaine  Amides  Lidocaine (Xylocaine®)  Mepivacaine (Carbocaine®)  Prilocaine (Citanest®)  Articaine (Septocaine®)  Bupivacaine (Marcaine®)

Local Anesthetics  Local anesthetics are vasodilators and are absorbed into the circulation  Vasoconstrictors are added to constrict blood vessels in the area of injection  Decreases rate of absorption  Decreases risk of toxicity  Prolongs the anesthetic action in the area

Topical Anesthesia  Used to minimize the discomfort of the dental injection  Should be used routinely with children  Gels are preferred in children (liquids and sprays are hard to control)  Benzocaine is available in concentrations up to 20 %, has a rapid onset, and toxic reactions are virtually unknown  Are absorbed systemically

Applying Topical Anesthetic  Dry area where the topical will be applied with a gauze  Apply small amount of topical with a cotton swab only to the area that the needle will be penetrating  Cover the cotton swab with the gauze and leave in place for seconds  Use age-appropriate language to explain the procedure, including sensation and taste

Injectable Local Anesthetics  Vary from almost all other drugs in one very significant way: with most other drugs clinical effectiveness does not develop until an adequate blood level of the drug is reached. Local anesthetics, on the other hand, have their effects terminated by absorption into the circulatory system. However, it is the blood level of the local anesthetic which is the determining factor of whether an overdose reaction will occur

Injectable Local Anesthetics  Drug is injected at or near the nerve trunk to produce a blockade of nerve impulses into the CNS. It produces a loss of sensation and sometimes a loss of motor activity

Injectable Local Anesthetics  Local anesthetic injected into an area of infection will have a delayed onset and its action may be prevented  Infected areas have a pH of 4-6 (normal is 7.4) which inhibits the anesthetic from crossing the nerve sheath  Inserting a needle into an active site of infection could lead to possible spread of the infection

Injectable Local Anesthetics  True allergy to local anesthetics is extremely rare, but can occur  A bisulfate preservative is used in anesthetics containing epinephrine. If the patient is allergic to bisulfates, anesthetics without vasoconstrictor should be used  Allergy to one amide does not rule out the use of another amide  Allergy to one ester does rule out the use of another ester

Technique for Local Anesthetic Delivery  Prepare the syringe away from patient’s view  Use age-appropriate, nonthreatening language to describe what you are doing (dripping warm sleepy juice next to your tooth to help it fall asleep)  Children are quick to pick up on your anxiety and apprehension. Be relaxed and calm

Technique for Local Anesthetic Delivery  Use 30 gauge short needles when possible (less force needed to penetrate and less pain)  Use 27 gauge long needle for mandibular blocks  Use intraseptal injections for palatal soft tissue anesthesia  Don’t exceed maximum doses  The numb feeling can be very frightening to children. Reassure them that this is exactly what they are supposed to feel and that the weird feeling will go away

Complications with Local Anesthetics  Toxicity  CNS  CVS  Allergy  Paresthesia  Post-operative soft tissue injury (cheek and lip biting)

Effects of Toxicity on the CNS  Biphasic reaction (excitation followed by depression)  Early: dizziness, anxiety, confusion  Later: diplopia, tinnitis, drowsiness  Objective signs: muscle twitching, tremors, slowed speech, shivering, seizure activity, unconsciousness, respiratory arrest

Effects of Toxicity on the CVS  Biphasic reaction  Initially stimulation (increased heart rate and blood pressure)  Followed by depression (decreased heart rate and blood pressure, cardiac arrest)  CVS response more resistant than CNS

Allergy to Local Anesthetic  Reaction can vary greatly  Urticaria  Dermatitis  Angioedema  Fever  Photosensitivity  Anaphylaxis

Paresthesia  Persistent anesthesia beyond the expected duration  Risk increases with local anesthetic percentage  Higher incidence with Articaine, Prilocaine  Causes:  Trauma to the nerve  Hemorrhage in the area around the nerve

Post-operative Soft Tissue Injury  Majority of cheek and lip biting lesions are self-limiting and heal without complications  Secondary infections may develop  Caregivers should be informed when local anesthetics are used  Location and duration of anesthesia  Necessary precautions to take while numb  OraVerse (phentolamine mesylate) not recommended for children < 6 years old

Preventing Complications  Know child’s weight  Know maximum doses for every anesthetic you intend to use  Know how to calculate the number of carpules you can safely use  Have printed dosage guides available in the clinic  Obtain accurate medical history and verify allergy information

Pain Management in Pediatric Dentistry  Pain is difficult to measure due to its subjectivity, especially in children  Majority of children respond well to non-opioid analgesics (NSAIDS and acetaminophen)

Pain Management in Pediatric Dentistry  Most cases of post-operative pain include an inflammatory component so NSIADs should be the first-line agents  Acetaminophen lacks anti-inflammatory properties but is a good alternative when NSAIDs are contraindicated.  Overdose of acetaminophen is common in children

Children’s Motrin  5-10 mg/kg every 8 hours  Oral drops 40 mg/ml  Oral suspension 100mg/5ml  Chewables 50 and 100 mg

Children’s Tylenol (Acetaminophen)  15 mg/kg every 4-6 hours  Infant drops 80 mg/0.8ml  80 mg chewables  Available in multiple forms and dosages (solution, elixer, suspension, syrup, suppository)