Anesthesia for Endodontics Flashcards
What are the factors that affect endodontic anesthesia?
-Apprehension and Anxiety
-Fatigue
-Tissue Inflamation
-Previous Unsucessful Anesthesia.
Root canal is impossible without…
profound anesthesia
What does the psychological approach to initial managment involve? (4 C’s)
- Control
- Communication
- Concern
- Confidence
What is an atraumatic anesthetic injection?
-Dry mucosa - then Topical anesthetic - let it soak in at least 60sec.
-Vigorously shaking or gently squeezing the lip or cheek while injecting is a distraction technique
-Slow and gentle
-Talk to patient constantly
-Keep patient occupied
How fast should you inject anesthesia?
SLOW! 60 seconds
How much anesthesia do you use on a palatal injection?
1/4 carp
What is more effective in reducing pain from palatal injections: refrigerant or topical gel?
refrigerant
Any ______ tooth may present problems in achieving adequate anesthesia
pulp inflamed
What situation is a challenge to get numb using anesthesia?
mandibular molar with acutely inflamed pulpitis
Local anesthesia less effective in what type of inflammation?
acutely inflamed tissues often VERY resistant to LA
“lip signs” do no necessarily indicate ____ anesthesia
PULPAL
-infiltration alone here is useless due to the density of the cortical plates
How to check for pulpal anesthesia?
EPT, cold testing, or percussion (whatever caused pain prior to anesthesia)
Why is anesthesia difficult with mandibular molars?
the inherent inaccuracies of mandibular N. blocks
What are the physiological and psychological challenges with anesthesia?
-Emotional Considerations
-Apprehension-Fear-Anxiety
-Fatigue-Hyperalgesia-Allodynia
-Decreased Pain Threshold
-History of Unsuccessful Anesthesia
-Popularized Fear of RCT
-Lack of Confidence in Provider
-Lack of Confidence by Provider
What can you do to combat local anesthesia problems?
- use an anti-inflammatory drug
- diminish the emotional component
- be certain you have a good block
- learn to effectively use supplemental anesthetic technique after a confirmed block
What level of anti-inflammatory drug should you prescribe?
- IBU 600 mg one hour prior = 78% effective
What do you need to prescribe meds?
Cannot prescribe w/o a DX or w/o examining pt
How to diminish the emotional component of anesthesia?
-establish rapport with the patient; show them you care
-communicate your concern for the patient in a calm, convincing, and confident manner
-inform before you perform
If you do a good IA block what signs should you see?
lip signs
ONLY AFTER YOU ARE POSITIVE that you have a NUMB and FAT LIP, do you use any _______ anesthesia
buccal
What is the process for numbing?
- Do initial IA and wait a few minutes to allow anesthesia in área of IA injection. Then go back and FEEL the BONE and painlessly inject the 2nd carpule where you know you need to be for the IA BLOCK.
- Then wait for “lipsigns” and check tooth with percussion and/or cold to determine if you need to do SUPPLEMENTARY anesthesia
What are the types of supplemental anesthetic after a confirmed block?
- Intra-ligamental (PDL injection)
- Intra-pulpal Injection
- Intra-osseous Injection
What are the 5 basic mandibular techniques to LA?
- Inferior Alveolar Nerve (IAN)
- Lingual Nerve (L)
- Bucal Infiltration
- Gow-Gates
- Incisive Nerve Block/Inflitration at the Mental Foramen
What nerve are you going for with an IAN?
inferior alveolar nerve
What nerve are you going for with an L?
lingual nerve
What branch of the trigeminal nerve are you targeting with IAN and L?
mandibular nerve (V3)
What nerve is just anterior to the IAN (inferior alveolar nerve)?
lingual nerve
What nerve enters the mandibular foramen?
IAN (inferior alveolar nerve)
Where do you inject for an IAN?
superior to the mandibular foramen
Where do you inject for a Lingual nerve block?
-superior to the mandibular foramen for the IAN
- then withdraw needle slightly for lingual
For a IAN or L block what do you do before you deposit?
-Aspirate
-Stabilize
-Distraction
Where is the point of penetrtion intraorally for the IAN or L block?
Just lateral to pterygomandibular raphe at the height of coronoid notch
- 6-10 mm above occlusal plane
What is the insertion path for a IAN or L block?
-Barrel of syringe is over opposite premolars.
-Syringe is parallel with mandibular occlusal plane.
-Advance » 20 – 25 mm (1 inch)
What are examples of IAN failures?
- Deposit below mandibular foramen
- Deposit anterior to mandibular foramen
- Deposit too posteriorly into parotid gland
What is the most common method of mandibular anesthesia?
IA
-more successful in molars and premolars
What method of anesthesia has the greatest number of failures?
IA
Lip numbness usually occurs in ______ minutes for a IAN
5-7 minutes
Pulpal anesthesia occurs in ________ minutes for an IAN
10-15 minutes
What is the duration of the IAN block?
2.5 hours
What is the sucess rate or an infiltration in mandible?
64%
Labial or lingual infiltrations injects are or are not effective for pulpal anesthesia in mandible
alone are not
What is better for the first mandibular molar infiltration: articaine or lidocaine?
articaine
What is the target for the gow-gate?
- target is neck of the condyle
Where do you position the syringe for a gow-gate?
over the contralateral premolars
Where and how far do you insert the needle for a gow-gate?
Insert the needle into mucosa distal to the maxillary 2nd molar until the neck of condyle is contacted
What is the extraoral landmark for the gow-gate?
external auditory meatus
What is the difference between the gow-gate and the standard IA injection?
What teeth is the incisive nerve bloock at the mental foramen successful for?
- premolars, but not central and lateral incisor
Where do you deliver anesthetic for the mylohyoid?
into the mucosal tissue apical and distal to the 1st molar
-used bc branches of IAN might innervate the 1st molar
What are the 5 basic anesthesia techniques for the maxilla?
- Infiltration
- Anterior Superior Alveolar (ASA)
- Middle Superior Alveolar (MSA)
- Posterior Superior Alveolar (PSA)
- Infraorbital Block
What are the main nerves we focus on in the maxilla for anesthesia?
- greater palatine (GPB)
- naso-palatine (NPB)
Infiltration is more successful in the maxilla or the mandible?
maxilla
How long for lip numbness with infiltration on maxilla?
a few minutes
A successful pulpal anesthesia on the maxilla has an onset of ________ minutes
3-5 minutes
What is the target area for the anterior superior alveolar (ASA)?
Primarily numbs the maxillary anterior teeth (incisors and canines) and the associated soft tissue
What is the technique for the anterior superior alveolar (ASA)?
The anesthetic is typically injected near the apex of the maxillary canine or incisor, which affects the ASA nerve
What is the duration of infiltration on maxilla posterior teeth?
45-60 minutes
What is the duration of infiltration on maxilla anterior teeth?
30-60 minutes
What is the target area for the middle superior alveolar (MSA)?
Premolars (first and second) and may also include the mesiobuccal root of the maxillary first molar, as well as the surrounding gingival and buccal tissues
What is the technique for the middle superior alveolar (MSA)?
Near the maxillary second premolar, specifically targeting the MSA nerve, which is a branch of the maxillary nerve.
What is the target area for the posterior superior alveolar (PSA)?
Maxillary molars (typically the first, second, and sometimes the third molars) and the associated buccal soft tissues.
What is the technique for the posterior superior alveolar (PSA)?
The anesthetic is injected near the posterior superior alveolar foramen, which is located on the maxilla, usually above the molar roots. The needle is typically inserted at a 45-degree angle to reach the nerve
What is the target area for the infraorbital block?
Maxillary anterior teeth (incisors and canines), premolars, and sometimes the mesiobuccal root of the maxillary first molar. It also affects the buccal soft tissues, upper lip, and sometimes the nasal region
What is the technique for the infraorbital block?
The anesthetic is injected near the infraorbital foramen, located just below the infraorbital rim
What is the target area for the greater palatine block?
Numbs the soft and hard tissues of theposterior hard palate, usually from the second molar to the midline, affecting the greater palatine nerve
What is the technique for the greater palatine block?
The anesthetic is injected at the greater palatine foramen, located on the hard palate, usually about 1-2 mm medial to the second molar. The needle is gently advanced into the foramen to deliver the anesthetic
What is the target area for the nasopalatine block?
Numbs the anterior hard palate, particularly the area around the maxillary incisors (central and lateral incisors) and the associated gingival tissues
What is the technique for the nasopalatine block?
The anesthetic is injected at the nasopalatine foramen, located just behind the maxillary central incisors. This is typically done by inserting the needle into the midline of the anterior palate, often requiring gentle aspiration to avoid blood vessels
Effective Pulpal Anesthesia will be routinely gone in _________ minutes
30-90
Should you numb a tooth that is necrotic?
YES
What are the two basic types of local anesthetic agents?
- Esters = (Novacaine, Procaine) more side effects, higher probability of allergic reaction, no longer in favor or commonly available in U.S.
- Amides = all the rest, available & preferred.
Most pulpal anesthesia will be lost after ___ minutes
45
What are the different types of amides and there durations?
- Short ( < 60 min.) 3% Mepivacaine (Carbocaine®)
- Medium (60-120 min.) Lidocaine, Articaine
- Long (> 120 min.) 0.5% Bupivacaine w/ 1:200,000 epi. (Marcaine®)
What should you be aware of when using amide local anesthetic?
Aspirate (REPEATEDLY) to AVOID INTRAVASCULAR injection
If you have a compromised patient (ASA III or IV) what should you do before treatment?
be certain to contact the patient’s physician for advice on anesthesia and other drugs planned for patient
- Best to fax, email or otherwise contact physician to obtain their input in writing
Most hot IP cases will require what?
one or more supplemental anesthetic techniques in addition to basic regional blocks and necessary infiltration
What are supplemental anesthetic techniques?
- Periodontal Ligament (PDL) Injections
- Intra-pulpal Injection
- Intra-osseous Injection
What is a periodontal ligament (PDL) injection?
- Needle wedged between root and
bone. - The key is achieving back pressure
- Achieves rapid onset but can be
uncomfortable to the patient and short in its duration
What is an intra-pulpal injection?
- The PDL injection may get you into the pulp but maybe NOT the canals.
- Last choice= (painful and ultra short acting but immediate relief)
What are the steps of an intra-pulpal injection?
- Use 30 gauge needle (#25 file) wedged as far in canal as possible.
- Must bind tightly in canal
- Warn patient – Injection will hurt
- Duration: minutes only (extirpation only – will not last for shaping or obturation) get pulp out NOW
- Do NOT count on repeating this
injection - Do distal canal of lower molar first
What is an intra-osseous injection?
- Distal to the target tooth.
- 2 mm apical to the CEJ.
- Stay in attached gingiva.
- Avoid roots, mental foramen, sinus.
What should you know about cellulitis and local anesthesia?
- Usually necrotic pulp so no IP problem but probably very sensitive to palpation & percussion*
- Never a good idea to inject into swollen tissue
- Localized swelling vs. cellulitis
- Referral of serious case
Strongly Consider _________ for initial treatment of cellulitis
REFERRAL
How do you perfect your LA technique?
- Use an effective, safe & appropriate LA agent
- Practice & use the most effective N. Block technique
- Utilize Alternative Injection Locations as applicable
- Wait until effective to start TX (check with Percussion, EPT or Endo ice – whatever had caused the pain prior to anesthesia)
- Continue to demonstrate concern for the patient
How do you demonstrate concern for the patient during your LA technique?
- Use topical anesthetic (effective or not)
- Use Endo-Ice for palatal injections
- Employ “Gate Theory” when injecting
- SLOW injection – reassure patient
- 27 gauge needle OK (30 gauge is NOT less pain –unless the patient thinks so – then use it)
Do NOT add ANY buccal infiltration until you have a…
Thick and Fat LIP
(Not just Tingling)
What is the mode of action of local anesthetics?
- cause reversible interruption of the conduction of impulses in peripheral nerves by causing a local decrease in the rate and degree of depolarization of the nerve membrane such that the threshold potential for transmission is not reached when everything goes well
- These effects are due to blockade of sodium channels, thereby impairing sodium ion flux across the membrane resulting in disruption of impulse conduction
Most local anesthetic agents are what kind of amide?
tertiary amine bases that are administered as water soluble hydrochlorides . After injection, the tertiary amine base is liberated by the relatively alkaline pH of normal tissue fluids
In tissue fluid the local anesthetic will be present in both an…
ionized and non-ionized form dependnig on the pH in the area
-only the non-ionized base diffuses through the nerve sheath, perineuronal tissues and neuronal membrane, to reach the axoplasm
If sufficient LA reaches the channel to be effective, what occurs?
In the non-ionized form, the LA enters the sodium channel and either occludes the channel or combines with a specific receptor within the channel that results in channel blockade
What is the most commonly used LA agent?
2% Lidocaine with 1:100,000 epi. (Xylocaine®)
What is the best choice of LA for a routine RCT at UMKC?
2% Lidocaine with 1:100,000 epi. (Xylocaine®)
What is the most controversial LA agent?
4% Articaine with 1:200,000 epi. (Septocaine®)
What does Septocaine contain that could cause allergy problems?
unique sulfur molecule
What is 4% Articaine with 1:200,000 epi. (Septocaine®) controversial?
Potential to cause neuropathies: paresthesia rare but 5 times as likely as with lidocaine or mepivicaine. Lawyers know this! Be Safe! Avoid N. Blocks with Articaine
What is the max safe dose of 4% Articaine with 1:200,000 epi. (Septocaine®) for an adult?
4 carpules
What is the max safe dose of 2% Lidocaine with 1:100,000 epi. (Xylocaine®) for an adult?
8 carpules
What is the purpose of epinephrine in LA?
Delays systemic absorption which increases the duration AND increases the effectiveness of the LA. Also retards bleeding (surgery).
What are the potential dangers of epinephrine in LA?
w/ epi. in a pt with elevated BP is an untoward further increase in BP (esp. w/ intravascular inj.)
How much endogenous epi does an adult produce at rest?
1 carp of LA epi/min
How much endogenous epi does an adult produce when stressed?
10 carps of LA epi/min
However, if after 3-4 carps, pt. still isn’t “numb”, seriously consider…
re-scheduling with sedation
What are the solutions to a hot maxillary tooth?
- Use a Regional Block
- PSA (infraorbital block)
- 2nd Div. Block (palatal infiltration)
Why should an anesthetic agent not be injected directly into a swelling before drained?
because the swelling has increased blood supply so the anesthetic is transported quickly into systemic circulation diminishing the effect in local tissues
What are the solutions to a hot mandibular tooth?
- Gow-Gates injection (designed to include the “high rising” mylo hyoid nerve)
