1.
Nerve impulses travel in myelinated nerves by a process called what?
Correct Answer
B. Saltatory conducation
Explanation
Saltatory conduction is when the nerve impulses jump from node to node. Anesthesia covers 2-3 nodes, and 8-10 mm
2.
Which portion of the nerve do local anesthetics work on?
Correct Answer
C. Nerve membrane
Explanation
Anesthesia only works on the nerve membrane. It won't and doesn't need to penetrate the myelin sheath.
3.
What is one important way that local anesthetic drugs differ from all other drugs used in dentistry?
Correct Answer
D. Action ceased when absorbed into bloodstream
Explanation
All other drugs must pass into the bloodstream to be effective. LA cease to exert an effect once they enter the bloodstream.
4.
When procaine undergoes metabolic breakdown, the major metabolic product (metabolite) is what?
Correct Answer
E. Para-aminobenzoic acid
Explanation
PABA - it is the byproduct of the metabolism of esters, and is what causes most allergic reactions.
5.
Biotransformation of amides takes place where?
Correct Answer
A. Liver
Explanation
The correct answer is liver. Biotransformation refers to the chemical alteration of a substance within an organism. In the case of amides, this process primarily occurs in the liver. The liver is responsible for metabolizing various substances, including drugs and toxins, through a series of enzymatic reactions. This biotransformation helps in the elimination of amides from the body and is an essential step in drug metabolism.
6.
The concentration of epinephrine that is optimal for hemostasis is what?
Correct Answer
B. 1:50,000
Explanation
The optimal concentration of epinephrine for hemostasis is 1:50,000. This means that for every 1 part of epinephrine, there are 50,000 parts of the solution. This concentration is commonly used in medical procedures to control bleeding because it constricts blood vessels, reducing blood flow to the area and promoting clotting.
7.
All of the following are reasons to include a vasoconstrictor, EXCEPT one. Which one is the EXCEPTION?
Correct Answer
B. Increase anesthetic blood levels
Explanation
Epinephrine is added to decrease the level of absorption of the local anesthetic, for safety, profundity, to decrease bleeding, slow absorption, decrease local anesthetic blood levels, and increase local anesthetic at the injection site.
8.
When it is necessary to administer more than one anesthetic drug, a safe total dose should be determined by not exceeding what?
Correct Answer
A. The lower of the two maximum doses for the individual agents
Explanation
When a patient cannot get numb, use a vasodilator then a vasoconstrictor. Do not exceed the MRD of the lesser of the 2.
9.
One of the many proprietary names for lidocaine is what?
Correct Answer
A. Xylocaine HCL
Explanation
The correct answer is Xylocaine HCL. Xylocaine HCL is one of the proprietary names for lidocaine, which is a local anesthetic commonly used in medical procedures. Lidocaine works by blocking nerve signals in the body, resulting in temporary numbness and pain relief. Xylocaine HCL is available in various forms such as injections, creams, and gels. It is widely used in dental procedures, minor surgeries, and as a numbing agent for skin conditions.
10.
A healthy patient weighing 155 lbs has been given 2 cartridges of 2% lidocaine with epinephrine 1:100,000. How many MORE cartridges of 3% Arestocaine can they have?
Correct Answer
B. 4.2
Explanation
The concentration of lidocaine with epinephrine given to the patient is 2%. The question asks for the number of MORE cartridges of 3% Arestocaine the patient can have. Since the concentration of Arestocaine is higher than the lidocaine given, the patient can have more cartridges of Arestocaine. Among the given options, 4.2 is the only value that represents a higher concentration of Arestocaine. Therefore, the correct answer is 4.2.
11.
All of the following are ways of caring for a syringe EXCEPT one. Which one is the EXCEPTION?
Correct Answer
E. Clean with an ultrasonic instrument
Explanation
When caring for a syringe, wash with soap and water, use a caviwipe, dismantle it and lube it every 5 times. Do not clean it with your ultrasonic.
12.
In the dental office, the MOST important consideration when selecting a syringe-type is the ability of the syringe to:
Correct Answer
B. Aspirate
Explanation
The most important consideration when selecting a syringe-type in the dental office is its ability to aspirate. Aspiration is a crucial step in dental procedures as it ensures that the needle is properly positioned and prevents the injection of anesthetic solution into a blood vessel. By aspirating, dentists can check for blood return, which indicates that the needle is not in a blood vessel. This helps to minimize the risk of complications and ensure the effectiveness of the anesthetic solution.
13.
In local anesthetic dissociation, tissues with a low pH would have what effect on base (RN) and cations (RNH+) in the solution?
Correct Answer
A. A lower protion of RN and a higher portion of RNH+
Explanation
In summary, in tissues with a low pH (more acidic environment), local anesthetics exist in their ionized form (RNH+) rather than their non-ionized form (RN). This shift in ionization reduces the effectiveness of the local anesthetic, leading to a lower proportion of RN and a higher proportion of RNH+. As a result, the local anesthetic becomes less potent and has a shorter duration of action, making it less effective at blocking nerve impulses.
14.
After properly loading the cartridge into the syringe, a few drops of local anesthetic should be expelled. Why?
Correct Answer
B. To ensure free flow of the solution
Explanation
To make sure the local anesthetic is free flowing.
15.
The major factor influencing the ability to aspirate is what?
Correct Answer
A. Gauge of the needle
Explanation
The diameter of the lumen or gauge of the needle.
16.
All of the following methods will REDUCE the chance of needle breakage, EXCEPT one - which one is the exception?
Correct Answer
C. Burying the needle to the hub
Explanation
Avoid needle breakage by not bending the needle, not redirecting the needle when embedded in tissue, never force the needle against resistance, do not bury needle to the hub, and by using a larger gauge (25 is best).
17.
The antioxidant used to preserve epinephrine in a local anesthetic solution is:
Correct Answer
A. Sodium bisulfate
Explanation
Sodium bisulfate is used as an antioxidant to preserve epinephrine in a local anesthetic solution. Antioxidants are substances that prevent the oxidation of other molecules, thereby protecting them from degradation or breakdown. In this case, sodium bisulfate helps to maintain the stability and effectiveness of epinephrine, which is a sensitive compound that can degrade over time. By inhibiting oxidation, sodium bisulfate ensures that the epinephrine remains potent and active in the local anesthetic solution.
18.
A small bubble of approximately 1 to 2 mm diameter will frequently be found in the local anesthetic cartridge. These bubbles are caused by?
Correct Answer
C. Nitrogen gas being pumped in during manufacturing
Explanation
During the manufacturing process of the local anesthetic cartridge, nitrogen gas is pumped in. This is the reason why a small bubble of approximately 1 to 2 mm diameter is frequently found in the cartridge.
19.
Distilled water is added to the cartridge for what purpose?
Correct Answer
D. To provide the volume of the solution
Explanation
Distilled water is added to the cartridge to provide the volume of the solution. This means that the water is added in order to increase the overall amount of solution in the cartridge, ensuring that there is enough liquid to administer the necessary dosage.
20.
Topical antiseptic does which of the following?
Correct Answer
C. Lessens the chance of inflammation or infection
Explanation
A topical anesthetic will disinfect the area, decrease infection, and decrease inflammation.
21.
What is the MOST important reason hemostats/cotton roll pliers are part of the armamentarium?
Correct Answer
C. They are used for the retrieval of a broken needle
Explanation
Hemostats/cotton roll pliers are an important tool in the armamentarium because they are specifically designed for the retrieval of a broken needle. In dental procedures, needles can occasionally break, and it is crucial to safely remove the broken piece to prevent any harm to the patient. Hemostats/cotton roll pliers have a strong grip and can securely grasp the broken needle, allowing the dentist to remove it without causing further damage or injury. This makes them an essential tool in dental practice to ensure patient safety and provide effective treatment.
22.
At what time are professionals MOST at risk for a needle stick?
Correct Answer
B. Recapping
Explanation
The most risk occurs while recapping the needle because then it's dirty.
23.
All of the following are acceptable ways of recapping a needle EXCEPT:
Correct Answer
A. Carefully directing the cap over needle with fingers
Explanation
The correct answer is "Carefully directing the cap over needle with fingers" because this method poses a risk of accidental needlestick injuries. The other options mentioned, such as utilizing a holding device, performing the one-handed scoop technique, implementing cotton roll pliers or a hemostat, and securing the cap with fingers on a vertical syringe, are all acceptable ways to recap a needle safely and minimize the risk of injury.
24.
Stacey, an 18-year-old soccer player, arrives for the extraction of teeth #4, 12, 20, and 28. She is given 5 cartridges of 4% Articaine with epi 1:100,000. Her mother calls 3 hours following the appointment stating that Stacey appears cyanotic and sluggish. Her nail beds look dark blue and the blood in the extraction sites is chocolate brown. What is MOST likely the condition presented?
Correct Answer
B. Methemoglobinemia
Explanation
The symptoms described in the question, such as cyanosis (bluish discoloration of the skin), sluggishness, dark blue nail beds, and chocolate brown blood, are consistent with methemoglobinemia. Methemoglobinemia is a condition where the iron in hemoglobin is oxidized, resulting in reduced oxygen-carrying capacity of the blood. This can be caused by certain medications, including local anesthetics like Articaine. Therefore, the most likely condition presented in this case is methemoglobinemia due to the local anesthetic overdose.
25.
A patient with epilepsy is scheduled for root planing and scaling with local anesthetic today. What should the dental hygienist know about this condition?
Correct Answer
B. In low doses local anesthetic is an anti-convulsant
Explanation
Stress reduction protocol and no N2O. Local anesthetic and epi OK.