CRDTS LA EXAM comprehensive questions and
answer latest upload 2024/ 2025 with 100% verified
solutions
Radiation therapy - ANSWER-compromised vascular bed in area
Levonodefrin - ANSWER-synthetic hormone
1/6 less potent compared to epi
used in higher concentration b/c of this 1:20,000
2% mepivicaine
Epi Dosage - ANSWER-0.2 mg healthy adult (11 carps)
0.04 mg compromised pt (2 carps)
Levo Dosage - ANSWER-1 mg normal
0.2 mg compromised =
Toxicity - ANSWER-increase HR, systolic BP
nausea, restlessness, racing heart, anxiety, weakness, tremor, severe headache,
hyperventilation, shaky
signs of toxicity are short lived due to metabolism of vasoconstrictor
Biotransformation - ANSWER-Blood (enzyme COMT)
Liver (MAO)
Duration of action - ANSWER-shortest to longest:
Mepi
Prilo
1|Page
,Lido
Arti
Bupivi
molly picks lemons, apples & bananas :)
Articaine - ANSWER-Amide or Ester: amide
Biotransformation: liver and plasma
How it comes: 4% 1:100,000 epi, 4% 1:200,000 epi
MRD: 3.2 mg/lb, NA mg per appt
60-75 min, 3-6 hrs soft tissue
Different Amides - ANSWER-Lidocaine, mepIvacaIne, bupIvacaIne, articaine
(amides have 2 I's in name)
be cautious if pt has liver diseases since amides are metabolized in liver
Different Esters - ANSWER-benzocaine, novocaine, procaine
highest allergic reactions
Bupivacaine - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 0.5% w/ 1:200,000 epi
MRD: 0.9 mg/lb, 90 mg
MOST TOXIC, LONGEST DURATION
Lidocaine (xylocaine) - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 1:50,000 epi, 1:100,000 epi
2|Page
,MRD: 3.2 mg/lb, 500mg
60 min, 3-5 hrs soft tissue
Mepivicaine - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 3% plain, 2% w/ levo
MRD: 3.2 mg/lb, 500mg
SHORTEST DURATION
60 min, 3-5 hrs for soft tissue
Prilocaine - ANSWER-Amide or Ester: amide
Biotransformation: liver, kidneys, lungs
How it comes: 4% plain, 4% w/ 1:200,000 epi
MRD: 4 mg/lb, 600mg
40-60 min, 2-4 hrs for soft
0.5% - ANSWER-9mg
2% - ANSWER-36mg
3% - ANSWER-54mg
4% - ANSWER-72mg
1:20,000 - ANSWER-0.09mg/cart
1:50,000 - ANSWER-0.036mg/cart
1:100,000 - ANSWER-0.018mg/cart
3|Page
, 1:200,000 - ANSWER-0.009mg/cart
Young's Rule - ANSWER-dose x age / sum of 12+ child's age
6 yr old, 2% lido
MRD 300mg x 6 yrs = 1800
+6 = 100mg
PSA - ANSWER-Penetration site: height of mucobuccal fold, DB root of 2nd or 3rd molars
Depth: 16mm- 9mm from hub
Deposition amount: 1/2-1 cart (.9-1.8ml)
Anesthetizes: mx molars except MB root of 1st molar
Extra: >3% positive aspiration, hematoma risk, no bony landmarks
MSA injection - ANSWER-Penetration site: height of vestibule, 2nd PM
Depth: 5-8mm
Deposition amount: 1/2-2/3 (.9-1.2)
Anesthetizes: mx PMs and MB root of 1st molar
Extra: can run into zygomatic bone, ballooning of tissue, hemorrhage, present in 28% of
population
ASA injection - ANSWER-Penetration site: height of vestibule in canine fossa, anterior to
eminence, 10 degree angle
Depth: 4-10mm, usually 3-6mm
Deposition amount: 1/2-2/3 (.9-1.2)
Anesthetizes: canine, lateral, central
Extra: watch for apex of canine, root is 17mm
NP - ANSWER-Penetration site: palatal mucosa lateral to the widest dimension of incisive
papilla
Depth: 4-7mm
Deposition amount: 0.2-0.4ml 1/8-1/4 carp
4|Page
answer latest upload 2024/ 2025 with 100% verified
solutions
Radiation therapy - ANSWER-compromised vascular bed in area
Levonodefrin - ANSWER-synthetic hormone
1/6 less potent compared to epi
used in higher concentration b/c of this 1:20,000
2% mepivicaine
Epi Dosage - ANSWER-0.2 mg healthy adult (11 carps)
0.04 mg compromised pt (2 carps)
Levo Dosage - ANSWER-1 mg normal
0.2 mg compromised =
Toxicity - ANSWER-increase HR, systolic BP
nausea, restlessness, racing heart, anxiety, weakness, tremor, severe headache,
hyperventilation, shaky
signs of toxicity are short lived due to metabolism of vasoconstrictor
Biotransformation - ANSWER-Blood (enzyme COMT)
Liver (MAO)
Duration of action - ANSWER-shortest to longest:
Mepi
Prilo
1|Page
,Lido
Arti
Bupivi
molly picks lemons, apples & bananas :)
Articaine - ANSWER-Amide or Ester: amide
Biotransformation: liver and plasma
How it comes: 4% 1:100,000 epi, 4% 1:200,000 epi
MRD: 3.2 mg/lb, NA mg per appt
60-75 min, 3-6 hrs soft tissue
Different Amides - ANSWER-Lidocaine, mepIvacaIne, bupIvacaIne, articaine
(amides have 2 I's in name)
be cautious if pt has liver diseases since amides are metabolized in liver
Different Esters - ANSWER-benzocaine, novocaine, procaine
highest allergic reactions
Bupivacaine - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 0.5% w/ 1:200,000 epi
MRD: 0.9 mg/lb, 90 mg
MOST TOXIC, LONGEST DURATION
Lidocaine (xylocaine) - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 1:50,000 epi, 1:100,000 epi
2|Page
,MRD: 3.2 mg/lb, 500mg
60 min, 3-5 hrs soft tissue
Mepivicaine - ANSWER-Amide or Ester: amide
Biotransformation: liver
How it comes: 3% plain, 2% w/ levo
MRD: 3.2 mg/lb, 500mg
SHORTEST DURATION
60 min, 3-5 hrs for soft tissue
Prilocaine - ANSWER-Amide or Ester: amide
Biotransformation: liver, kidneys, lungs
How it comes: 4% plain, 4% w/ 1:200,000 epi
MRD: 4 mg/lb, 600mg
40-60 min, 2-4 hrs for soft
0.5% - ANSWER-9mg
2% - ANSWER-36mg
3% - ANSWER-54mg
4% - ANSWER-72mg
1:20,000 - ANSWER-0.09mg/cart
1:50,000 - ANSWER-0.036mg/cart
1:100,000 - ANSWER-0.018mg/cart
3|Page
, 1:200,000 - ANSWER-0.009mg/cart
Young's Rule - ANSWER-dose x age / sum of 12+ child's age
6 yr old, 2% lido
MRD 300mg x 6 yrs = 1800
+6 = 100mg
PSA - ANSWER-Penetration site: height of mucobuccal fold, DB root of 2nd or 3rd molars
Depth: 16mm- 9mm from hub
Deposition amount: 1/2-1 cart (.9-1.8ml)
Anesthetizes: mx molars except MB root of 1st molar
Extra: >3% positive aspiration, hematoma risk, no bony landmarks
MSA injection - ANSWER-Penetration site: height of vestibule, 2nd PM
Depth: 5-8mm
Deposition amount: 1/2-2/3 (.9-1.2)
Anesthetizes: mx PMs and MB root of 1st molar
Extra: can run into zygomatic bone, ballooning of tissue, hemorrhage, present in 28% of
population
ASA injection - ANSWER-Penetration site: height of vestibule in canine fossa, anterior to
eminence, 10 degree angle
Depth: 4-10mm, usually 3-6mm
Deposition amount: 1/2-2/3 (.9-1.2)
Anesthetizes: canine, lateral, central
Extra: watch for apex of canine, root is 17mm
NP - ANSWER-Penetration site: palatal mucosa lateral to the widest dimension of incisive
papilla
Depth: 4-7mm
Deposition amount: 0.2-0.4ml 1/8-1/4 carp
4|Page
