An interventional study of Comfort-in Needle-Free Injection System and Conventional Dental Injection in Dental Anxiety, Dental Pain and Pulpotomy, sponsored by Ondokuz Mayıs University. Completed at 1 site in Turkey (Türkiye). Open to participants aged 5 Years to 8 Years. Per ClinicalTrials.gov, last updated 2026-05-14.
Sponsored by Ondokuz Mayıs University · Not applicable, Interventional, and Treatment
This randomized split-mouth clinical trial evaluated the efficacy of the Comfort-in needle-free injection system compared with conventional dental injection for local anesthesia during pulpotomy treatment in children.
Sixty children aged 5 to 8 years who required bilateral pulpotomy of primary first molars were included. Each participant received both anesthesia techniques in separate treatment sessions with an interval of at least one week. The order of anesthesia techniques was randomized: 30 children received conventional dental injection in the first session and Comfort-in needle-free injection in the second session, while the remaining 30 children received the interventions in the reverse order.
Pain perception during anesthesia administration and pulpotomy was assessed using the Face, Legs, Activity, Cry, Consolability scale and the Wong-Baker FACES Pain Rating Scale. Physiological parameters, including blood pressure, pulse, and oxygen saturation, were recorded before anesthesia, after anesthesia, and after pulpotomy. The amount of anesthetic solution used, duration of anesthetic effect, postoperative complications, and patient preference were also recorded.
The study was designed to determine whether the Comfort-in needle-free injection system could provide effective local anesthesia for pediatric pulpotomy while reducing injection-related pain, physiological stress responses, anesthetic volume, duration of postoperative numbness, and postoperative complications compared with conventional dental injection.
Local anesthesia administration is one of the major sources of pain, fear, and anxiety in pediatric dental patients. Conventional dental injections may cause discomfort due to needle penetration, tissue pressure, and deposition of anesthetic solution. These experiences may negatively affect child cooperation and future dental attendance. Needle-free injection systems have been developed as an alternative method to deliver local anesthetic solution without needle penetration.
This randomized split-mouth clinical trial compared the Comfort-in needle-free injection system with conventional dental injection in children requiring pulpotomy treatment of bilateral primary first molars. The split-mouth design was used to allow each child to serve as his or her own control, thereby reducing interindividual variability in pain perception and physiological responses.
A total of 60 children aged 5 to 8 years were included. All participants required pulpotomy treatment of bilateral primary first molars located in either the maxilla or mandible. Eligible children had no previous experience with local anesthesia or dental treatment, had no systemic disease or mental disability, had not used medications that could affect pain perception, and demonstrated positive or definitely positive behavior according to the Frankl Behavior Rating Scale during the initial examination.
Each child received both anesthesia techniques in two separate clinical sessions with a minimum interval of one week. In one session, conventional local anesthesia was administered using a dental injector after topical anesthetic application. In the other session, local anesthesia was administered using the Comfort-in needle-free injection system after topical anesthetic application. The sequence of interventions was randomized. Thirty children received conventional injection first and Comfort-in needle-free injection second; the remaining 30 children received Comfort-in needle-free injection first and conventional injection second.
In the conventional injection session, the injection site was dried and topical anesthetic spray was applied for 60 seconds. Local anesthetic solution containing articaine hydrochloride with epinephrine 1:100,000 was then administered using a 27-gauge dental injector. In the Comfort-in session, the injection site was similarly dried and topical anesthetic spray was applied for 60 seconds. Articaine hydrochloride with epinephrine 1:100,000 was administered using the Comfort-in needle-free injection system.
Pain during anesthesia administration and pulpotomy was assessed using two validated pediatric pain assessment tools: the Face, Legs, Activity, Cry, Consolability scale and the Wong-Baker FACES Pain Rating Scale. Physiological parameters, including systolic blood pressure, diastolic blood pressure, pulse, and oxygen saturation, were recorded before anesthesia, after anesthesia, and after pulpotomy. The total amount of anesthetic solution used, duration of anesthetic effect, postoperative complications, and the child's preference for anesthesia technique were also recorded.
The primary aim of the study was to compare pain perception during local anesthesia administration between the Comfort-in needle-free injection system and conventional dental injection. Secondary aims included comparing anesthetic efficacy during pulpotomy, physiological responses, amount of anesthetic solution required, duration of anesthetic effect, postoperative complications, and patient preference between the two anesthesia techniques.
142 studies on the registry are indexed under Toothache; 28 are open to participants now.
This study's enrollment of 60 is below the median of 84 across 123 interventional studies indexed under Toothache.
Browse Toothache studies →Ondokuz Mayıs University is the lead sponsor of 277 studies on the registry; 62 are open to participants now.
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Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants in this arm received conventional dental injection in the first treatment session and Comfort-in needle-free injection in the second treatment session. The two sessions were performed on contralateral primary first molars requiring pulpotomy, with a minimum interval of one week between sessions.
Device: Comfort-in Needle-Free Injection System · Procedure: Conventional Dental Injection
Participants in this arm received Comfort-in needle-free injection in the first treatment session and conventional dental injection in the second treatment session. The two sessions were performed on contralateral primary first molars requiring pulpotomy, with a minimum interval of one week between sessions.
Device: Comfort-in Needle-Free Injection System · Procedure: Conventional Dental Injection
The Comfort-in needle-free injection system was used to administer local anesthetic solution without needle penetration. After drying the injection site and applying topical anesthetic spray for 60 seconds, articaine hydrochloride with epinephrine 1:100,000 was administered using the Comfort-in system before pulpotomy treatment of the primary first molar.
Conventional local anesthesia was administered using a dental injector. After drying the injection site and applying topical anesthetic spray for 60 seconds, articaine hydrochloride with epinephrine 1:100,000 was administered using a 27-gauge dental injector before pulpotomy treatment of the primary first molar.
Pain during local anesthesia administration assessed by the FLACC scale
Pain-related behavior during local anesthesia administration was assessed using the Face, Legs, Activity, Cry, Consolability (FLACC) scale. The FLACC scale evaluates five behavioral categories: face, legs, activity, cry, and consolability. The total score ranges from 0 to 10, with higher scores indicating greater pain.
Time frame: Periprocedural at Visit 1 and Visit 2, during local anesthesia administration; visits were separated by at least 1 week.
Pain during local anesthesia and pulpotomy assessed by the Wong-Baker FACES Pain Rating Scale
Self-reported pain was assessed using the Wong-Baker FACES Pain Rating Scale. Scores range from 0 to 10, with higher scores indicating greater pain. Pain scores were recorded after local anesthesia administration and after pulpotomy treatment for both anesthesia techniques.
Time frame: Immediately after local anesthesia administration and immediately after pulpotomy in each treatment session
Pain during pulpotomy procedure steps assessed by the FLACC scale
Pain-related behavior during pulpotomy was assessed using the FLACC scale at different procedural steps, including high-speed instrumentation, low-speed instrumentation, pulp removal, matrix-wedge placement, and restoration. The total FLACC score ranges from 0 to 10, with higher scores indicating greater pain.
Time frame: Periprocedural at Visit 1 and Visit 2, during prespecified pulpotomy procedure steps.
Systolic blood pressure
Systolic blood pressure was recorded as a physiological parameter to evaluate the response to the anesthesia technique and dental treatment.
Time frame: Immediately before anesthesia, immediately after anesthesia, and immediately after pulpotomy in each treatment session
Diastolic blood pressure
Diastolic blood pressure was recorded as a physiological parameter to evaluate the response to the anesthesia technique and dental treatment.
Time frame: Immediately before anesthesia, immediately after anesthesia, and immediately after pulpotomy in each treatment session
Pulse rate
Pulse rate was recorded as a physiological parameter to evaluate the response to the anesthesia technique and dental treatment.
Time frame: Immediately before anesthesia, immediately after anesthesia, and immediately after pulpotomy in each treatment session
Oxygen saturation
Oxygen saturation was recorded as a physiological parameter during the dental treatment session.
Time frame: Immediately before anesthesia, immediately after anesthesia, and immediately after pulpotomy in each treatment session
Total amount of anesthetic solution used
The total volume of local anesthetic solution used for each anesthesia technique was recorded in milliliters.
Time frame: Periprocedural at Visit 1 and Visit 2, during local anesthesia administration.
Duration of anesthetic effect
The duration of anesthetic effect after local anesthesia administration was recorded in hours for each anesthesia technique.
Time frame: Immediately after local anesthesia administration in each treatment session
Postoperative complications after local anesthesia
Postoperative complications after local anesthesia were recorded for each anesthesia technique. Complications included lip biting, swelling, hematoma, and pain.
Time frame: Up to 24 hours after Visit 1 and Visit 2
Number of Participants Preferring Each Anesthesia Technique Assessed by a Direct Preference Question
After experiencing both anesthesia techniques, participants were asked which technique they preferred: conventional dental injection or Comfort-in needle-free injection. Data were reported as the number of participants preferring each anesthesia technique.
Time frame: At completion of Visit 2
Plan to share: No — Individual participant data will not be shared because the study included pediatric participants and specific consent for external sharing of individual participant-level data was not obtained. Aggregate study results will be reported in the manuscript.
Ran from Jan 2019 to primary completion in Dec 2021, 35 months.
Of 44 non-industry interventional studies with no phase under Toothache, half reached primary completion within 5 months of starting (the median), counting those still running; a quarter within 3 and three quarters within 15. This study's 35 months is above that.
Counting every sponsor, half of 45 studies reached it within 5 months; a quarter within 3 and three quarters within 12.
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This study is completed, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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