Local Anesthesia chapter 4 Exam 2026
Questions and Answers
which vasoconstrictor is most widely used in dentistry and the most potent?
epinephrine
levonordefrin
felypressin
all options listed - Correct answer-epinephrine
A 1:100,000 dilution of epinephrine for obtaining pupal anesthesia may be used in
combination with a relatively small infiltrated dose of 1:50,000 to decrease
bleeding. This is a particularly important strategy for dental hygienists to use
during provision of nonsurgical periodontal therapy. - Correct answer-both are true
The addition of sodium bisulfite preservative can reduce the efficiency of the
quaternary amide to dissociate into the unchanged tertiary amide base necessary to
penetrate the lipid rich membrane of nerve because the preservative can increase
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, the pH of the anesthetic solution. - Correct answer-the statement is correct but the
reason is not ?
The undesirable effects of epinephrine are short lived because of the rapid
inactivation of epinephrine by the re-uptake of adrenergic nerves. - Correct answer-
both statement and reason are correct and related
Patients with a relative contraindication for vasoconstrictors can receive
epinephrine containing local anesthetic agents in the lowest possible dose, not to
exceed the MRD of 0.04 mg per appointment. Using the best technique, in general,
there are only a few absolute contraindications to the use of vasoconstrictors, and
in most situations, limiting the amount of vasoconstrictor a patient can receive
produces the benefits of vasoconstrictor use in local anesthesia without
compromising the patient. - Correct answer-both are true
why are vasoconstrictors added to local anesthetics?
a. to increase the potency of the local anesthetics
b. to inhibit the oxidation of the local anesthetic
c. to counteract the vasodilating properties of the local anesthetic
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Questions and Answers
which vasoconstrictor is most widely used in dentistry and the most potent?
epinephrine
levonordefrin
felypressin
all options listed - Correct answer-epinephrine
A 1:100,000 dilution of epinephrine for obtaining pupal anesthesia may be used in
combination with a relatively small infiltrated dose of 1:50,000 to decrease
bleeding. This is a particularly important strategy for dental hygienists to use
during provision of nonsurgical periodontal therapy. - Correct answer-both are true
The addition of sodium bisulfite preservative can reduce the efficiency of the
quaternary amide to dissociate into the unchanged tertiary amide base necessary to
penetrate the lipid rich membrane of nerve because the preservative can increase
©COPYRIGHT 2025, ALL RIGHTS RESERVED 1
, the pH of the anesthetic solution. - Correct answer-the statement is correct but the
reason is not ?
The undesirable effects of epinephrine are short lived because of the rapid
inactivation of epinephrine by the re-uptake of adrenergic nerves. - Correct answer-
both statement and reason are correct and related
Patients with a relative contraindication for vasoconstrictors can receive
epinephrine containing local anesthetic agents in the lowest possible dose, not to
exceed the MRD of 0.04 mg per appointment. Using the best technique, in general,
there are only a few absolute contraindications to the use of vasoconstrictors, and
in most situations, limiting the amount of vasoconstrictor a patient can receive
produces the benefits of vasoconstrictor use in local anesthesia without
compromising the patient. - Correct answer-both are true
why are vasoconstrictors added to local anesthetics?
a. to increase the potency of the local anesthetics
b. to inhibit the oxidation of the local anesthetic
c. to counteract the vasodilating properties of the local anesthetic
©COPYRIGHT 2025, ALL RIGHTS RESERVED 2
