Reducing Pain During Dental Nerve Block Injections in Children

Summary

Title of Study: Effect of External Cooling and Vibration, Counterstimulation, and Needle Type on Pain, Physiological, and Behavioral Outcomes During Inferior Alveolar Nerve Block in Pediatric Patients

Why was this study done? The inferior alveolar nerve block (IANB) is a dental injection used to numb the lower jaw and teeth in children. Many children find this injection very painful and scary. Bad experiences can make them afraid of the dentist for years. This study was designed to test different ways to make the injection less painful and stressful for children.

What did the researchers want to find out?

They planned to compare three different methods to see which one works best to reduce pain, distress, and physical signs of fear (like a fast heartbeat) during the injection:

External cooling + vibration (using a special device that cools and vibrates on the skin near the injection site)

Counterstimulation (gentle tapping or pressing with a cotton roll near the injection site)

A thinner needle (30-gauge instead of the standard 27-gauge)

Standard method (27-gauge needle with no extra distraction) - this is the control group

Who took part? The study enrolled 166 healthy children between the ages of 5 and 9 years who needed a lower jaw dental injection at Al-Mustansiriyah University Dental College.

What happened during the study?

Children were randomly placed into one of the four groups. All children received the same numbing medicine (2% lidocaine with epinephrine). Dentists gave the injection at the same speed for everyone. Researchers planned to measure:

How much pain the child felt (using the Wong-Baker Faces scale, where children point to a face showing their pain level)

How much pain the child showed (using the FLACC scale, which looks at face, legs, activity, crying, and comfort)

Heart rate and oxygen level (using a finger clip device)

How well the child cooperated (using the Frankl Behavior Rating Scale)

What outcomes are being measured? The primary outcomes are children's self-reported pain and observer-rated pain behavior. Secondary outcomes include physiological responses (heart rate and oxygen saturation) and behavioral cooperation scores. The study will compare changes in these measures across the four intervention groups.

What is the purpose of this research? The findings from this trial are expected to provide evidence to help dentists choose the most effective comfort measures to keep children calm and pain-free during lower jaw injections. The study aims to clarify whether distraction-based methods (cooling+vibration or counterstimulation) offer advantages over simply changing the needle gauge.

Were there any side effects or risks? Safety is being monitored continuously throughout the procedure via pulse oximetry (oxygen saturation) and heart rate tracking. The interventions are considered low-risk, and children who show excessive distress are withdrawn and managed according to standard care.

Who paid for this study? The study received no outside funding. The authors declared no conflicts of interest.

Where was the study done? Department of Pediatric Dentistry, Al-Mustansiriyah University, Baghdad, Iraq.

Conditions

• Dental Anxiety
• Inferior Alveolar Nerve
• Pain Management

Interventions

DEVICE

Buzzy Device

A thermomechanical device providing simultaneous vibration and cooling, placed externally at the injection site for 30-60 seconds before and during local anesthetic deposition.

PROCEDURE

Counterstimulation

Gentle manual tapping and pressure applied with a cotton roll adjacent to the injection site throughout the injection to provide tactile distraction.

DEVICE

30-Gauge Needle

A 30-gauge long dental needle used for the inferior alveolar nerve block.

DEVICE

27-Gauge Needle

A 27-gauge long dental needle used for the inferior alveolar nerve block (standard control).

DRUG

Lidocaine hydrochloride 2% with epinephrine 1:100 000

2% lidocaine with 1:100,000 epinephrine administered as a local anesthetic for the inferior alveolar nerve block at 1 mL/min.

Sponsors & Collaborators

• Al-Mustansiriyah University

  lead OTHER

Study Design

Allocation

RANDOMIZED

Purpose

SUPPORTIVE_CARE

Masking

SINGLE

Model

PARALLEL

Eligibility

Min Age

5 Years

Max Age

9 Years

Sex

ALL

Healthy Volunteers

Yes

Timeline & Regulatory

Start

2025-02-01

Primary Completion

2025-09-30

Completion

2025-09-30

Countries

• Iraq

Study Locations