Comparison of Five Anesthetic Delivery Systems for Palatal Infiltration (PAL-INJECT)

Sercan Küçükkurt

Status: Completed

Conditions: Dental; Dental Anxiety; Palatal Anesthesia; Pain

Treatments: Device: Manual Pressure Syringe (MCJ, ASPIJECT™); Device: Needle-Free Jet Injector (NFI, Comfort-in™); Device: Computer-Controlled Local Anesthetic Delivery (CCLAD, CALAJECT™); Device: Spring-Activated Syringe (PCJ, PAROJECT™); Device: Conventional Dental Syringe

Study type: Interventional

Funder types: Other

Identifiers

NCT07184879

IAU-PalatalRCT-2025

Details and patient eligibility

About

This study is a randomized clinical trial evaluating five different anesthetic delivery systems for palatal infiltration in adults undergoing maxillary molar extraction. A total of 200 healthy volunteers were enrolled and randomly assigned to receive anesthesia using one of the following devices: conventional dental syringe, manual pressure syringe, spring-activated syringe, needle-free jet injector, or computer-controlled local anesthetic delivery system.

The purpose of the study is to compare patient-reported pain, dental fear, and physiological responses (pulse rate and oxygen saturation) associated with each system. The results are expected to provide evidence on which devices may improve patient comfort and cooperation during palatal infiltration procedures.

Full description

This randomized, parallel-arm superiority trial was conducted at Istanbul Aydın University, Faculty of Dentistry, between September 2023 and March 2025. Two hundred healthy adults (≥18 years) requiring maxillary molar extraction under palatal infiltration anesthesia were equally randomized into five groups (n=40).

All participants received 0.4 mL of 4% articaine with 1:100,000 epinephrine, delivered with one of the five systems. The primary outcome was pain perception measured immediately after injection using a visual analog scale (VAS). Secondary outcomes included changes in dental fear, pulse rate, oxygen saturation, and any adverse events.

The study was approved by the Istanbul Aydın University Ethics Committee. Written informed consent was obtained from all participants.

Enrollment: 200 patients

Sex: All

Ages: 18+ years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• Age ≥ 18 years
• ASA physical status I or II
• No systemic conditions affecting anesthetic metabolism
• No known allergy to local anesthetics or vasoconstrictors
• No psychiatric disorders or anxiolytic medication
• Ability to provide written informed consent

Exclusion criteria

• Pregnancy or lactation
• Active infection at the injection site
• Diagnosed needle phobia
• Prior exposure to any of the tested injection systems
• Use of premedication, sedatives, or topical anesthetics on the day of the procedure

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Double Blind

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200 participants in 5 patient groups

Conventional Dental Syringe (CDS)

Experimental group

Description:

Palatal infiltration using a conventional dental syringe with 27G needle; manual injection of 0.4 mL articaine with epinephrine over 15-20 seconds, with aspiration. Intervention Name: Device: Conventional Dental Syringe

Treatment:

Device: Conventional Dental Syringe

Manual Pressure Syringe (MCJ)

Experimental group

Description:

Palatal infiltration using ASPIJECT™ manual pressure syringe with 30G, 16 mm needle; manually controlled injection of 0.4 mL articaine with epinephrine over 15-20 seconds, with aspiration. Intervention Name: Device: Manual Pressure Syringe (ASPIJECT™)

Treatment:

Device: Manual Pressure Syringe (MCJ, ASPIJECT™)

Spring-Activated Syringe (PCJ)

Experimental group

Description:

Palatal infiltration using PAROJECT™ spring-activated syringe; two calibrated 0.2 mL doses of articaine with epinephrine following aspiration. Intervention Name: Device: Spring-Activated Syringe (PAROJECT™)

Treatment:

Device: Spring-Activated Syringe (PCJ, PAROJECT™)

Needle-Free Jet Injector (NFI)

Experimental group

Description:

Palatal infiltration using Comfort-in™ needle-free jet injector; 0.4 mL articaine with epinephrine delivered in \<1 second, at 4-5 bar pressure; aspiration not applicable. Intervention Name: Device: Needle-Free Jet Injector (Comfort-in™)

Treatment:

Device: Needle-Free Jet Injector (NFI, Comfort-in™)

Computer-Controlled Local Anesthetic Delivery (CCLAD)

Experimental group

Description:

Palatal infiltration using CALAJECT™ Program I; 30G, 16 mm needle; AutoFlow delivery (0.006-0.009 mL/s) with automatic aspiration; microprocessor-controlled constant pressure. Intervention Name: Device: Computer-Controlled Local Anesthetic Delivery (CALAJECT™)

Treatment:

Device: Computer-Controlled Local Anesthetic Delivery (CCLAD, CALAJECT™)