the effectiveness of the IANB.
6-8 The success may be
augmented through the use of buffered articaine.
Inadequate anesthesia of anterior teeth may result due
to incisive nerve crossover. Providing the incisive block
on contralateral side has been shown to be a good
9 For the purposes of NSPT, adequate lingual
anesthesia (not provided by incisive block) can be easily
achieved in limited areas by providing interpapillary
infiltrations at the mesial and distal aspects of the teeth
2 The infiltrations should be comfortable for the
patient because the facial tissues will already be
anesthetized by the incisive block. Alternatives include
the administration of supraperiosteal injections or PDL
3. Bifid IA nerve—In less than 1% of the population,
bifid IA nerve may be present and may result in
inadequate anesthesia. Often a second, more inferiorly
positioned mandibular canal is visible on the radiograph.
Solutions include depositing local anesthetic more
inferior to traditional landmarks, administering
supraperiosteal injections on buccal and lingual of teeth
affected, or administration of PDL injections.
4. Additional strategies—Studies have shown that the
use of buffered local anesthetic results in a more
comfortable injection and more rapid onset;
articaine is safe and more successful in producing
anesthesia than lidocaine for infiltration and blocks;
that positioning the patient upright after the injection
facilitates diffusion of the local anesthetic in the area.
Technique protocols, recommendations for agents, and
armamentarium evolve. Frequent review of evidence-based
approaches to providing mandibular anesthesia is essential
for safe and effective pain control. RDH
1. Webb L. Best practices in local anesthesia teaching methodology
for dental hygiene education. Victoria, BC Canada: CDHA National
Conference poster sessions; October 2015.
2. Malamed S. Handbook of Local Anesthesia. 6th ed. St. Louis, MO:
3. Logothetis DD. Local Anesthesia for the Dental Hygienist. 2nd ed. St.
Louis, MO: Elsevier; 2017.
4. Bassett B, DiMarco A, Naughton D. Local Anesthesia for Dental
Professionals. New York, NY: Pearson; 2010.
5. Malamed S. Is the mandibular block passé? JADA. 2011;142( 9
6. Meechum JG. The use of mandibular infiltration anesthetic
technique in adults. JADA. 2011;142(9suppl): 19S-24S.
7. Malamed S. Articaine 30 years later. Oral Health. http://www.
oralhealthgroup.com/features/1003919408/ Published February 4,
2016. Accessed April 15, 2016.
8. Kanaa JM, Whitworth JM, Corbett IP, Meechan JG. Articaine buccal
infiltration enhances the effectiveness of lidocaine inferior alveolar
nerve block. Int Endodont J. 2009;42:238-246.
9. Webb L. Investigating the incisive block. RDH. 2015; 35( 9):94–96.
10. Malamed S, Tavana S, Falkal M. Faster onset and more
comfortable injection with alkalinized 2% lidocaine 1:100,000
epinephrine. Compendium of Dental Education-Aegis.
2013; 34( 1): 10–20.
usually anesthetized from deposition at the target.
Of course, authors have differing views, but with regard
to the Halstad approach, they seem pretty consistent.
TIPS AND TRICKS
There are probably as many approaches to the IANB as there
are clinicians. Described below are a few suggestions for correcting errors and avoiding insufficient anesthesia during provision of the IANB for NSPT.
1. Deposition too low (below mandibular foramen) is the
most common error and the most common cause of
failure. To correct, reinsert 5–10 mm superior to the
original injection site. Many years ago, when I was
working at a periodontal office in Milpitas, California, an
endodontist showed me a technique that improved my
success rate: palpate the internal oblique ridge with a
nondominant finger and follow it superiorly. The insertion
site is directly over the finger at the point where the
internal oblique ridge is no longer palpable. Using this
approach, the anesthetic is deposited higher (see Figure
7), above the target area of the traditional IANB and below
the target for the Gow-Gates technique.
2. Accessory innervation—Inadequate anesthesia of the
mesial portion of the mandibular first molar may result
due to accessory innervation, which many experts
suggest is likely due to lack of anesthesia to the mylohyoid
nerve. Solutions have included providing ( 1) the
mylohyoid nerve block,
4 ( 2) PDL injections, or the ( 3)
Gow-Gates or Vazirani-Akinosi nerve blocks. However,
recent studies have shown that a supplemental buccal
supraperiosteal injection at the apex of the mandibular
first molar using half a cartridge of 4% articaine increases
Figure 7: Left side;
palpate inner ridge
(black dashed line)
finger; slide it
posteriorly until ridge
just over the top of
that point (white X);
angle and advance
per traditional IANB.
Slashed blue circle
site of traditional