Digital vs Conventional Stabilizing Splints in Temporomandibular Disorders

Official title

A Randomized Controlled Trial Comparing Digitally Fabricated and Conventional Stabilizing Splints in the Management of Temporomandibular Disorders

Overview

This randomized controlled trial aims to compare the clinical effectiveness of digitally fabricated and conventionally fabricated maxillary stabilization splints in patients diagnosed with Temporomandibular Disorders (TMD) according to Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Participants will be randomly allocated in a 1:1 ratio to receive either a Digitally fabricated splint produced using computer-aided design and three-dimensional printing technology or a conventionally fabricated splint using standard impression and laboratory techniques. The primary outcome is Change in Pain Intensity measured using the Characteristic Pain Intensity component of the Graded Chronic Pain Scale (GCPS), 0-100 scale. Higher scores indicate greater pain severity from baseline to 3 months as primary end point. Secondary outcomes include change in pain-related disability assessed using the Graded Chronic Pain Scale (GCPS) disability score, change in maximum mouth opening measured in millimeters (mm), change in jaw functional limitation assessed using the Jaw Functional Limitation Scale (JFLS), resolution of temporomandibular joint (TMJ) clicking (present/absent), change in oral health-related quality of life assessed using the Oral Health Impact Profile-14 (OHIP-14), and compliance with splint use measured as average nightly wear time (hours per night). Assessments will be conducted at baseline and 3 months post-intervention. Outcome assessment will be performed by a blinded examiner.

Detailed description

This study is a parallel-group randomized controlled clinical trial designed to evaluate the effect of fabrication technique on the clinical performance of stabilization splints in patients with temporomandibular disorders (TMD). Eligible participants will be diagnosed according to Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) Axis I criteria. Following informed consent, participants will be randomly assigned in a 1:1 ratio to either the digitally fabricated splint group or the conventionally fabricated splint group using a computer-generated randomization sequence. Allocation concealment will be ensured by sequentially generated numbered, opaque, sealed envelopes prepared by an independent investigator.

For the digital workflow, maxillary and mandibular arches will be captured using an intra oral scanner. Splints will be designed using computer-aided design software and fabricated using additive manufacturing (three-dimensional printing) with biocompatible resin materials via digital light processing (DLP) technology. Post-processing will include cleaning and light curing according to standardized protocols.

For the conventional workflow, impressions will be obtained using elastomeric materials, followed by cast fabrication and articulation. Stabilization splints will be fabricated using heat-cured acrylic resin according to standardized laboratory procedures.

To ensure comparability between groups, splint design parameters will be standardized. All appliances will be maxillary full-coverage stabilization splints with even and simultaneous bilateral contacts in centric relation and canine-guided occlusion during excursive movements. Splint thickness will be standardized (approximately 2-3 mm), and all appliances will be adjusted intraorally at delivery to achieve uniform occlusal contacts.

Participants will be instructed to wear the splints nightly for a minimum of 8 hours. Clinical evaluations will be conducted at baseline and 3 months post-intervention. Outcome assessment will be performed by an examiner blinded to group allocation.

Data will be analyzed using IBM SPSS Statistics (version 26.0; IBM Corp., Armonk, NY, USA). A two-sided p-value \< 0.05 will be considered statistically significant.. Normality will be assessed using the Shapiro-Wilk test. Between-group comparisons will be performed using independent t-tests or Mann-Whitney U tests, as appropriate. Within-group comparisons will be conducted using paired t-tests or Wilcoxon signed-rank tests. Repeated measures will be analyzed using repeated measures ANOVA or mixed-effects models.

This study is designed to isolate the effect of fabrication technique by controlling splint design variables while employing clinically relevant material systems, thereby providing evidence on the comparative effectiveness of digitally fabricated and conventionally fabricated stabilization splints in the management of temporomandibular disorders.

Interventions

• Device Conventional Stabilizing Splint
  A conventional stabilizing splint is a removable dental appliance that fits over the upper or lower teeth. It is made using traditional laboratory methods from heat cure acrylic material based on a standard impression of the patient's teeth.
• Device Digital Stabilizing Splint
  A digital stabilizing splint is a removable appliance that fits over the teeth and is made using digital scanning and three dimensional printing technology. A digital scan of the patient's teeth is used to design the splint on a computer, and it is then fabricated using three dimensional printing technology using a biocompatible material.

Primary outcome measures

• Change in Pain Intensity [Time frame: Baseline to 3 months post-intervention]

Secondary outcome measures (6)

• Change in Pain-Related Disability [Time frame: Baseline to 3 months post-intervention]
• Change in maximum mouth opening (MMO) [Time frame: Baseline to 3 months post-intervention]
• Change in Jaw Functional Limitation [Time frame: Baseline to 3 months post-intervention]
• Resolution of Temporomandibular joint (TMJ) clicking [Time frame: Baseline and 3 months post intervention]
• Change in oral health-related quality of life [Time frame: Baseline to 3 months post-intervention]
• Compliance with splint use [Time frame: From intervention (day of splint delivery) to 3 months post-intervention, with compliance recorded continuously and summarized as average nightly wear time at 3 months.]

Eligibility criteria

Inclusion criteria

• Adults aged 18-40 years
• Diagnosis of Temporomandibular Disorder (TMD) according to standardized Diagnostic Criteria for Temporomandibular disorders Axis I
• Maximum unassisted mouth opening between 20-30 mm
• Symptoms present for ≥3 months (to exclude transient/self-limiting cases)
• Willingness to comply with study protocol and provide informed consent

Exclusion criteria

• Diagnosis of temporomandibular joint myalgia or Myofascial pain as the primary condition
• History of trauma to the temporomandibular joint or mandible
• Presence of degenerative joint diseases (e.g., osteoarthritis, rheumatoid arthritis)
• Congenital or developmental craniofacial anomalies affecting temporomandibular joint
• Prior temporomandibular joint surgery or ongoing orthodontic treatment
• Current use of: Analgesics, muscle relaxants, or anti-inflammatory drugs affecting temporomandibular joint symptoms
• Prior Occlusal splint therapy within the last 3 months
• Systemic conditions affecting joint function (e.g., connective tissue disorders)
• Pregnancy or lactation (if intervention may influence compliance or physiology

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: No

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Single blind

Primary purpose

Treatment

Study locations

Pakistan · 1 center

• Shifa College of Dentistry — Islamabad

Identifiers

NCT: NCT07566936 · IRB 243-25 · 053-2025

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗