Aspirating anesthetic syringe (breech-loading, harpoon type)

The dental anesthetic syringe has a thumb ring, finger grip, barrel, piston with a harpoon, and a needle adapter. It is breech-loading: the cartridge goes in through an opening on the side. The harpoon (a small barbed hook on the piston tip) sticks into the rubber stopper so the dentist can aspirate (pull back slightly) to make sure the needle is not in a blood vessel.

How to spot it

• Metal barrel with a window, thumb ring at the back, finger grip and a threaded tip for the needle.
• Look for the small sharp harpoon at the end of the piston.

What it is used for

• Load the cartridge (rubber stopper toward the harpoon), engage the harpoon with gentle finger pressure (do not hit the piston, which can crack the glass), then attach the needle.
• Pass it out of the patient's sight, below the chin, with the cap on.

Safety and care

• Semicritical item (it touches the inside of the mouth): clean it, package it and heat-sterilize it after every patient.
• The used needle is a sharp: never recap with two hands; use a one-handed scoop or a recapping device.
• Remove the needle and cartridge with care and put the needle in the sharps container before cleaning the syringe.

Related

• Anesthetic cartridge
• Dental anesthetic needles (long and short)
• Needle recapping device
• Topical anesthetic

Sources: New York City College of Technology (CUNY), DEN 2318. Lecture Session 10: Local Anesthesia Armamentarium, Malamed SF. Handbook of Local Anesthesia, 7th ed. Elsevier, 2020, Dentalcare.com CE643. The Concepts of Four-handed Dentistry Including Ergonomic Instrument Transfer. Pages: zones of activity, single-handed transfer, two-handed transfer, scissors/hinged instruments, syringe transfer, non-locking forceps, OSHA. Standard interpretation, 1994-04-29, recapping of contaminated needles (29 CFR 1910.1030), OSHA. Bloodborne Pathogens Standard, 29 CFR 1910.1030