Effect of Anterior Disc Displacement With Reduction on Postoperative Pain After Root Canal Treatment (TMD-POSTOP)

Does Anterior Disc Displacement With Reduction Affect Postoperative Pain After Root Canal Treatment in Patients With Symptomatic Apical Periodontitis? A Prospective, Quasi-Experimental Controlled Study

The aim of this study is to evaluate the impact of anterior disc displacement with reduction (ADDR) on postoperative pain following root canal treatment in patients diagnosed with symptomatic apical periodontitis.

Study Overview

• Status: Completed
• Conditions: Anterior Disc Displacement; Temporomandibular Disorders (TMDs); Symptomatic Apical Periodontitis
• Intervention / Treatment: Procedure: Single-Visit Conventional Root Canal Treatment Using Nickel-Titanium Rotary Instruments (Endoart Smart Gold); Drug: Ibuprofen 400 mg (if necessary)

Detailed Description

This prospective clinical study included individuals diagnosed with symptomatic apical periodontitis who had a vital mandibular molar tooth and were diagnosed with anterior disc displacement with reduction (ADDR) according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) (n = 45), as well as individuals without any temporomandibular joint pathology (n = 45). Following patient dropouts, a total of 70 patients with complete and eligible data were included in the final analysis, with 35 participants in each group.

All root canal treatments were performed by the same clinician using a standardized treatment protocol. Postoperative pain intensity was assessed using the Numeric Rating Scale at 6 and 12 hours and at 1, 2, 3, 5, and 7 days after treatment. In addition, joint sounds, joint pain, and maximum mouth opening were recorded in the preoperative period and at the 7-day postoperative follow-up, and their associations with postoperative pain were analyzed.

The findings of this study provide insight into the relationship between temporomandibular joint disorders and endodontic postoperative pain and may contribute to improved clinical understanding.

• Study Type: Interventional
• Enrollment (Actual): 70
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Turkey (Türkiye)
  • Rize Province
    • Rize, Rize Province, Turkey (Türkiye)
      • Recep Tayyip Erdogan University Faculty of Dentistry

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Individuals aged between 18 and 65 years with no systemic disease
• Patients diagnosed with symptomatic apical periodontitis
• Presence of a vital permanent mandibular first or second molar tooth requiring root canal treatment
• Teeth with no radiographic evidence of periapical changes or only slight widening of the periodontal ligament space
• Patients reporting preoperative spontaneous pain with a Numeric Rating Scale (NRS) score between 4 and 10 (moderate pain: 4-6; severe pain: 7-10)
• Patients reporting pain intensity of 4 or higher on the NRS during percussion testing
• Patients diagnosed with isolated anterior disc displacement with reduction according to the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) (experimental group) or patients without any temporomandibular joint disorder or pathology (control group)

Exclusion Criteria:

• Teeth found to have necrotic pulp tissue during access cavity preparation
• Patients in whom the study tooth was not located on the same side as the temporomandibular joint diagnosed with anterior disc displacement with reduction
• Occurrence of any endodontic complications during treatment
• Use of medications that could affect pain perception (e.g., analgesics or anti-inflammatory drugs) within at least 12 hours before treatment, or use of systemic antibiotics within one month prior to enrollment
• History of major jaw trauma, dentofacial deformities, or previous temporomandibular joint surgery
• Concurrent use of steroids, muscle relaxants, or narcotic medications
• History of diagnosed neuropathic pain, myofascial pain, neuralgic pain, or chronic headache disorders
• Presence of periodontal disease (probing depth > 5 mm or tooth mobility greater than Grade I) or teeth lacking adequate coronal structure
• Teeth without occlusal contact or with premature contacts, patients with bruxism or clenching habits, or patients with fewer than three teeth on one side of the mandible
• Inability to read, understand, or complete the pain assessment scale or to provide the required follow-up data
• Presence of significant cognitive impairment (e.g., communication deficits, intellectual disability) or diagnosed psychiatric disorders (e.g., depression, anxiety disorders)
• Presence of immature teeth or teeth with open apices
• Pregnant or breastfeeding women

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: Triple

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: ADDR group; Patients diagnosed with anterior disc displacement with reduction according to the Diagnostic Criteria for Temporomandibular Disorders.	Procedure: Single-Visit Conventional Root Canal Treatment Using Nickel-Titanium Rotary Instruments (Endoart Smart Gold); All endodontic treatments were performed in a single visit by a single operator (BR) with six years of clinical experience, using a standardized treatment protocol. Only one tooth per patient was included in the study. Inferior alveolar nerve block anesthesia was administered. After rubber dam isolation, access cavities were prepared. Working length was determined using an electronic apex locator set at 0.5 mm short of the apical foramen and confirmed with periapical radiography. Root canals were prepared using Endoart Smart Gold rotary instruments (Inci Dental, Istanbul, Türkiye) up to size 25/.04 for mesial canals and 30/.04 for distal canals. If insufficient apical instrumentation was detected, canal enlargement was extended up to a maximum of two sizes larger, according to canal length and anatomy. Following canal preparation, final irrigation was performed. The canals were obturated using the lateral condensation technique with a resin-based root canal sealer.; Drug: Ibuprofen 400 mg (if necessary); Ibuprofen (oral analgesic) was prescribed to all patients who underwent root canal treatment and was recommended for use only in case of postoperative pain.
Active Comparator: Control group; Patients without any temporomandibular joint pathology.	Procedure: Single-Visit Conventional Root Canal Treatment Using Nickel-Titanium Rotary Instruments (Endoart Smart Gold); All endodontic treatments were performed in a single visit by a single operator (BR) with six years of clinical experience, using a standardized treatment protocol. Only one tooth per patient was included in the study. Inferior alveolar nerve block anesthesia was administered. After rubber dam isolation, access cavities were prepared. Working length was determined using an electronic apex locator set at 0.5 mm short of the apical foramen and confirmed with periapical radiography. Root canals were prepared using Endoart Smart Gold rotary instruments (Inci Dental, Istanbul, Türkiye) up to size 25/.04 for mesial canals and 30/.04 for distal canals. If insufficient apical instrumentation was detected, canal enlargement was extended up to a maximum of two sizes larger, according to canal length and anatomy. Following canal preparation, final irrigation was performed. The canals were obturated using the lateral condensation technique with a resin-based root canal sealer.; Drug: Ibuprofen 400 mg (if necessary); Ibuprofen (oral analgesic) was prescribed to all patients who underwent root canal treatment and was recommended for use only in case of postoperative pain.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Postoperative pain intensity	To evaluate postoperative pain, each patient was provided with a pain diary after root canal treatment and was instructed to record pain intensity using the Numeric Rating Scale (NRS). Detailed instructions on how to use the NRS were given to all participants. Pain intensity was recorded at 6, 12, 24, 48, and 72 hours and at 5 and 7 days after treatment. Patients were prescribed 400 mg ibuprofen for use only in cases of severe pain. Data from patients who used analgesics during the follow-up period were excluded from the analysis.	6, 12 hours 1, 2, 3, 5 and 7 days postoperatively

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Maximum mouth opening	Maximum mouth opening was measured in millimeters using a digital caliper during the preoperative examination and at the 7-day postoperative follow-up.	Baseline and 7 days postoperatively
Temporomandibular joint pain and percussion sensitivity	Temporomandibular joint pain and percussion sensitivity of the treated tooth were evaluated using the Numeric Rating Scale during the preoperative period and at the 7-day postoperative follow-up.	Baseline and 7 days postoperatively

Collaborators and Investigators

• Sponsor: Recep Tayyip Erdogan University
• Investigators: Principal Investigator: Edanur Maraş, DDS, PhD, Recep Tayyip Erdoğan University, Faculty of Dentistry, Department of Endodontics

Study record dates

Study Major Dates

• Study Start (Actual): March 10, 2025
• Primary Completion (Actual): July 1, 2025
• Study Completion (Actual): July 14, 2025

Study Registration Dates

• First Submitted: December 15, 2025
• First Submitted That Met QC Criteria: December 26, 2025
• First Posted (Actual): January 9, 2026

Study Record Updates

• Last Update Posted (Actual): January 9, 2026
• Last Update Submitted That Met QC Criteria: December 26, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Postoperative pain; Endodontics; Temporomandibular Joint Disorders; Temporomandibular Joint; Root Canal Therapy
• Additional Relevant MeSH Terms: Pain; Neurologic Manifestations; Musculoskeletal Diseases; Stomatognathic Diseases; Muscular Diseases; Postoperative Complications; Pathologic Processes; Joint Diseases; Jaw Diseases; Mandibular Diseases; Craniomandibular Disorders; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Pain, Postoperative; Temporomandibular Joint Disorders; Organic Chemicals; Carboxylic Acids; Acids, Carbocyclic; Phenylpropionates; Ibuprofen
• Other Study ID Numbers: 2025/82 (Other Identifier: Recep Tayyip Erdoğan University Clinical Research Ethics Committee)

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Individual participant data will not be shared.

Drug and device information, study documents

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