Comparison of Five Anesthetic Delivery Systems for Palatal Infiltration

Palatal infiltration anesthesia using a conventional dental syringe with a 27G needle. A total of 0.4 mL of articaine 4% with epinephrine 1:100,000 was administered manually over 15-20 seconds following aspiration.

Palatal infiltration using a spring-activated push-button syringe (PAROJECT™). Two calibrated 0.2 mL doses of articaine 4% with epinephrine 1:100,000 were administered following aspiration.

Palatal infiltration using a needle-free jet injector (Comfort-in™). A total of 0.4 mL of articaine 4% with epinephrine 1:100,000 was delivered in less than one second at 4-5 bar pressure. Aspiration not applicable.

Palatal infiltration using a computer-controlled local anesthetic delivery system (CALAJECT™, Program I) with a 30G, 16 mm needle. AutoFlow rate 0.006-0.009 mL/s, with automatic aspiration after 5 seconds and constant microprocessor-controlled pressure. A total of 0.4 mL of articaine 4% with epinephrine 1:100,000 was administered.

Palatal infiltration using a manual pressure-controlled syringe (ASPIJECT™) with a 30G, 16 mm needle. A total of 0.4 mL of articaine 4% with epinephrine 1:100,000 was administered manually over 15-20 seconds with aspiration.