Effectiveness of INJEX Versus Traditional Syringe During Restoration of Primary Teeth

January 6, 2026 updated by: satish vishwanathaiah, University of Jazan

Effectiveness of INJEX Versus Traditional Syringe During Restoration of Primary Teeth: A Randomized Split-mouth Clinical Trial

The main purpose of this study is to make a comparison between pain perception levels and the behavior of patients during the restoration process in children between a needleless local anesthetic system (INJEX) and the conventional syringe technique. The main purpose of this study is to make a comparison between pain perception levels and the behavior of patients during the restoration process in children between a needleless local anesthetic system (INJEX) and the conventional syringe technique.

. The main questions it aims to answer are:

  1. To evaluate pain perception for restoration of primary molars with a needle free system in a pediatric population.
  2. To evaluate pain perception for restoration of Primary molars with needle syringe [Traditional syringe system] method in a pediatric population
  3. Time required to deliver anesthesia using needle free system vs Needle syringe [ traditional syringe system] Participants who enrolled in the study will be anesthetized according to the respective groups i,e INJEX (needle free system) and traditional dental needle system and restoration will be done.

Study Overview

Status

Completed

Conditions

Detailed Description

Before the start of the study a written informed consent and ascent was obtained from each parent of the children included in the study stating they accepted the treatment. Ethical clearance will be obtained before the start of the study. Patients reporting to the dental clinics, college of dentistry will be included in the study.

Sample size estimation:

The sample size was determined using the following formula, based on a difference in mean Face, Legs, Activity, Cry, and Consolability (FLACC) scores of 1.2 and a pooled standard deviation of 1.89. Sample Size (n) = 2Sp2 (Z 1-α/2+Z1-β) 2 µd2 where, Z (1-α/2) = 1.96 for a 95% confidence interval Z1-β = 0.84 for 80% power Sp2 = pooled standard deviation µd = 1.2 (difference in mean between groups) Substituting these values, the sample size was estimated to be 21. An additional 20% of the estimated sample size was added to account for any potential sampling loss, bringing the final sample size to a total of 25 teeth in each group.

study design: It was a split mouth randomized controlled trial

Randomization:

Teeth designated for restoration were assigned to one of two groups using a simple randomization method with a 1:1 allocation ratio. The allocation was performed using a predetermined list, with the first list for the right side, and the second for the left side. Allocation concealment was maintained through sealed envelopes until the time of intervention to prevent selection bias. On the intervention day, patients identified their number on either the right or left side lists.

Group I: All teeth in this group underwent restoration using the traditional syringe system. Making use of a conventional syringe fitted with a 27-gauge needle (Hogen Spitze, C-K Dental IND.CO., LTD.) local infiltration of Scandicaine 2% Special (mepivacaine hydrochloride and adrenaline) was given.

Group II: Teeth in this group received treatment with the needle-free injection system, INJEX (INJEX Pharma AG, Germany).

Intervention procedure To mitigate any operator-related bias, a single operator conducted the entire anesthesia protocol for all participants in the trial. Utilizing the "Tell-Show-Do" technique, all relevant treatment equipment and protocols were introduced and explained. The injection was thoroughly described using appropriate euphemisms or age-appropriate language.

A sterile dry gauze was used to cleanse the treatment area at the injection site before administering LA. Following this, a very small quantity of topical anesthetic (Benzocaine 20%, NJ, USA) was given and left to remain for a minimum time of 1 minute. Following the application of topical anesthesia, LA was administered based on the participant's assigned group.

After a standard waiting time of 3 minutes for the anesthesia to take effect, dental caries were removed , The pulp capping material, Dycal (Dentsply Caulk, Milford, DE, USA), was placed, and a type IX glass ionomer cement (GC Corporation, Tokyo, Japan) liner was applied before the final restoration with composite material.

Study Type

Interventional

Enrollment (Actual)

50

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

    • Jazan Region
      • Jizan, Jazan Region, Saudi Arabia, 45142
        • College of Dentistry

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Child

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Children aged 7 - 10 years
  • Existence of deep carious Primary molar, indicated for Indirect pup capping.
  • Complete physical and mental health without any confounding medical history
  • Parents who gave written informed consent

Exclusion Criteria:

  • Children below 7 years of age
  • Children complaining of irreversible pulpitis.
  • Children with Negative behaviour according to the wright's modification of
  • Frankl Behaviour Rating scale (FBRS) during initial examination
  • Children with medical or mentally compromised

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Quadruple

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Active Comparator: Needle syringe
traditional dental needle
already described
Other Names:
  • Syringe Needle [ Traditional technique]
Experimental: INJEX
Needle less device
already described
Other Names:
  • Syringe Needle [ Traditional technique]

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
The Face, Legs, Activity, Cry, and Consolability (FLACC) Scale
Time Frame: during and immediately after the delivery of anesthesia
FLACC gives an observational pain scale during the delivery of anesthesia
during and immediately after the delivery of anesthesia

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Wong Baker Scale
Time Frame: During and immediately after the delivery of anesthesia
Used to self-assess and effectively communicate the severity of pain they may be experiencing
During and immediately after the delivery of anesthesia
Pulse rate
Time Frame: Before the delivery of anesthesia, immediately after the delivery of anesthesia, and 1 minute after the delivery of anesthesia
comfort and patient acceptance during treatment
Before the delivery of anesthesia, immediately after the delivery of anesthesia, and 1 minute after the delivery of anesthesia
Time of local anesthesia administration
Time Frame: during the delivery of anesthesia
comfort and patient acceptance during treatment
during the delivery of anesthesia
Frankel Behaviour Rating Scale ( FBRS)
Time Frame: before the delivery of anesthesia, during the delivery of anesthesia and after the delivery of anesthesia
Frankel 1 -- definitely negative, Frankel 2 - Negative, Frankel 3 - positive, Frankel 4 - Definitely positive
before the delivery of anesthesia, during the delivery of anesthesia and after the delivery of anesthesia

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

February 16, 2024

Primary Completion (Actual)

May 30, 2024

Study Completion (Actual)

June 30, 2024

Study Registration Dates

First Submitted

August 26, 2024

First Submitted That Met QC Criteria

August 26, 2024

First Posted (Actual)

August 29, 2024

Study Record Updates

Last Update Posted (Actual)

January 8, 2026

Last Update Submitted That Met QC Criteria

January 6, 2026

Last Verified

January 1, 2026

More Information

Terms related to this study

Other Study ID Numbers

  • University Jazan

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Child Behavior

Clinical Trials on INJEX [ Needle less anesthesia]

Subscribe