Related Experiment Video
Updated: Aug 17, 2026

Multilevel Oblique Lumbar Interbody Fusion in Degenerative Lumbar Disc Disease with Instability
Published on: July 25, 2025
Clinical and functional outcomes in disc displacement with reduction and without reduction: A comparative study
Muhammet Bahattin Bingül1, Aziz Dengiz2, Mehmet Emrah Polat1
1Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Harran University, Şanlıurfa, Turkey.
Background:
Disc displacement with reduction (DDwR) and disc displacement without reduction (DDwoR) are recognized as distinct diagnostic entities, but comparative data on their functional and physical parameters remain limited.
Objective:
To compare functional and physical parameters between DDwR and chronic DDwoR patients.
Methods:
This cross-sectional study included 204 patients with TMJ internal derangement per DC/TMD criteria (91 DDwR, 113 DDwoR). Pain, chewing efficiency, joint sounds, mandibular range of motion, muscle palpation, and occlusal parameters were assessed.
Results:
DDwoR patients showed greater masticatory pain (p = .013), lower chewing efficiency (p = .004), higher masseter tenderness (p < .001), and more restricted mouth opening and movement (p < .001) than DDwR patients. No differences emerged in pain intensity, activity interference, joint sounds, temporal tenderness, tinnitus, deviation, or midline discrepancy (p > .05). .
Conclusions:
DDwoR carries a greater functional and mechanical burden than DDwR. Beyond pain alone, mandibular mobility, masseter tenderness, and occlusal features may improve subtype-specific diagnosis and treatment.
Related Concept Videos
Degenerative Disc Disease I: Introduction
Degenerative Disc Disease ll: Pathophysiology