COMT, MAOA, and SLC6A4 Polymorphisms and Inferior Alveolar Nerve Block Success

The Relationship Between COMT, MAOA, and SLC6A4 Polymorphisms and the Success of Inferior Alveolar Nerve Block

The purpose of this study was to evaluate the association between COMT, MAOA, and SLC6A4 genetic polymorphisms and the success of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis in mandibular molars. Patients presenting with moderate to severe pain were enrolled. Before anesthesia, pain intensity was assessed using the Heft-Parker Visual Analog Scale (HP-VAS), and pulpal vitality was evaluated using cold and electric pulp tests. All participants received a standardized inferior alveolar nerve block with 4% articaine containing epinephrine. Fifteen minutes after injection, pulpal anesthesia was reassessed using cold and electric pulp tests. Patients who continued to respond to these tests were considered to have unsuccessful pulpal anesthesia and were excluded from the study. Patients with no response to either test were included in the study, and root canal treatment was initiated. Pain experienced during the procedure was assessed using the HP-VAS. Buccal swab samples were collected for genomic DNA isolation, and COMT, MAOA, and SLC6A4 polymorphisms were analyzed using a Real-Time PCR-based TaqMan genotyping assay. The association between genetic polymorphisms and the success of inferior alveolar nerve block was statistically evaluated.

Study Overview

• Status: Completed
• Conditions: Symptomatic Irreversible Pulpitis (SIP)
• Intervention / Treatment: Procedure: Inferior Alveolar Nerve Block with 4% Articaine

• Study Type: Interventional
• Enrollment (Actual): 95
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Istanbul
    • Istanbul, Istanbul, Turkey (Türkiye), 34854
      • Faculty of Dentistry, Marmara University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Age between 15 and 60 years. American Society of Anesthesiologists (ASA) Physical Status I. Positive response to both the cold test and electric pulp test before treatment.

Presence of pulpal bleeding upon access cavity preparation, confirming pulp vitality.

Periodontal probing depth ≤3 mm. Sufficient coronal tooth structure to allow rubber dam isolation. No use of nonsteroidal anti-inflammatory drugs (NSAIDs) within 12 hours before enrollment.

No known allergy or hypersensitivity to articaine. No history of systemic or genetic diseases. Ability and willingness to provide written informed consent

Exclusion Criteria:

Use of nonsteroidal anti-inflammatory drugs (NSAIDs) within 12 hours before enrollment.

Known allergy or hypersensitivity to articaine. Presence of any systemic or genetic disease. Teeth with previous endodontic treatment. Teeth with extensive coronal destruction preventing rubber dam isolation. Presence of internal or external root resorption.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm

Intervention / Treatment

Experimental: Standard Inferior Alveolar Nerve Block

Procedure: Inferior Alveolar Nerve Block with 4% Articaine; A standardized inferior alveolar nerve block was administered using 4% articaine with epinephrine to patients with symptomatic irreversible pulpitis in mandibular molars. Fifteen minutes after injection, pulpal anesthesia was evaluated using cold and electric pulp tests. Participants who continued to respond to either test were considered to have unsuccessful pulpal anesthesia and were excluded from the study. Root canal treatment was initiated in participants who showed no response to both tests. Pain experienced during treatment was assessed using the Heft-Parker Visual Analog Scale (HP-VAS). Anesthetic success was defined as an HP-VAS score of less than 54 mm, whereas an HP-VAS score of 54 mm or greater was considered anesthetic failure.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Success of Inferior Alveolar Nerve Block Anesthesia	Anesthetic success was defined as an HP-VAS score of less than 54 mm during access cavity preparation and root canal treatment in patients with symptomatic irreversible pulpitis. An HP-VAS score of 54 mm or greater was considered anesthetic failure.	During root canal treatment.

Collaborators and Investigators

• Sponsor: Marmara University
• Investigators: Principal Investigator: Nevin kartal, Prof.Dr, Marmara University Faculty of Dentistry

Study record dates

Study Major Dates

• Study Start (Actual): November 12, 2025
• Primary Completion (Actual): April 2, 2026
• Study Completion (Actual): April 28, 2026

Study Registration Dates

• First Submitted: July 5, 2026
• First Submitted That Met QC Criteria: July 5, 2026
• First Posted (Actual): July 13, 2026

Study Record Updates

• Last Update Posted (Actual): July 13, 2026
• Last Update Submitted That Met QC Criteria: July 5, 2026
• Last Verified: July 1, 2026

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Sulfur Compounds; Organic Chemicals; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds; Thiophenes; Carticaine
• Other Study ID Numbers: 25.09.2025/2025-66

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No