L.A 4 Flashcards
Local anesthetic instruments
- Anesthetic carpules (Cartridge).
- Syringe.
- Needle.
• Additional Armamentarium: - Mouth props.
- Retractors.
- Topical antiseptic
- Topical aneasthetic.
- Applicator sticks.
- Cotton gauze (2x2 inches).
- Hemostat.
Carpules consists of
- Cylindrical glass tube.
- Stopper (plunger).
- Aluminum cap.
- Diaphragm.
Contents of a L.A cartridge
- Local anesthetic agent
- Vasoconstrictor
- Antioxidant (reducing agent), Sodium metabisulfite.
Vasoconstrictor preservative, can cause allergy to susceptible pt. - Sodium chloride, to make the solution isotonic body tissues.
- Distilled water.
- Fungicidal agent, e.g. Thymol
Methylparaben
was in use as a preservative for the anesthetic agent.
Nowadays it has been removed as it can cause allergic
reaction in some patients.
Types of Dental Syringes
- Non-disposable syringes:
a. Metallic, aspirating, side-loading (breech loading) or top- loading.
b. Plastic, aspirating, side-loading (breech loading) or top-loading.
c. Metallic, self aspirating, side-loading (breech loading) or top- loading.
d. Pressure syringe for periodontal ligament injection.
e. Jet injector (needleless syringe). - Disposable syringe.
- Safety syringe.
- Computer controlled local anesthetic delivery system.
Parts of a dental syringe
- Needle adapter
- Piston with harpoon
- Syringe barrel
- Finger grip
- Thumb ring
Metallic, aspirating, side-loading
(breech-loading) or top-loading
Advantages:
Disadvantages:
Advantages:
• Visible cartridge.
• Aspiration with one
hand.
• Autoclavable.
• Rust resistant.
Disadvantages:
• Weight (heavier than
plastic syringe).
• Syringe may be too big
for small operator.
• Possibility of infection
with improper care.
self-aspirating syringes required a….
thumb disk
Disposable Syringes lack ?
a thumb ring, aspiration requires the
use of both hands.
Proper care and handling of L.A syringes
- After each use the syringe should be washed, rinsed and sterilized.
- After every 5 autoclavings
- The harpoon should be cleaned with a brush after each use.
- Pistons and harpoons may need to be replaced after a long term use.
The larger the gauge the..
smaller the
internal diameter of the needle.
Length:
• Short- 20mm (20-25mm)
• Long- 32mm (30-35mm)
– Monobeveled
Steps of Scoop technique
Step 1: Place the cap on a flat surface, then remove your hand from the cap.
Step 2: With one hand, hold the syringe and use the needle to “scoop up” the cap.
Step 3: When the cap covers the needle completely, use the other hand to secure the cap on the needle hub.
Potential problems with L.A needles
- Pain on insertion.
- Needle breakage.
- Pain on withdrawal.
- Injury to the patient or adminstrator.
