NCT07673471

Brief Summary

This study investigated whether the shape of the face affects how jaw muscles respond to botulinum toxin injections in people who grind their teeth (bruxism). Participants were divided into two groups based on their facial structure: low-angle (shorter face height) and normal-angle. Each participant received botulinum toxin type A injections into the masseter (jaw) muscle. Bite force measurements were taken before and 15 days after the injection using the T-Scan computerized occlusal analysis system. The study aimed to determine whether facial structure influences the early changes in bite force balance following the injection.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
34

participants targeted

Target at P25-P50 for not_applicable

Timeline
Completed

Started Feb 2026

Shorter than P25 for not_applicable

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

February 9, 2026

Completed
3 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 8, 2026

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

May 8, 2026

Completed
2 months until next milestone

First Submitted

Initial submission to the registry

June 23, 2026

Completed
6 days until next milestone

First Posted

Study publicly available on registry

June 29, 2026

Completed
Last Updated

June 29, 2026

Status Verified

June 1, 2026

Enrollment Period

3 months

First QC Date

June 23, 2026

Last Update Submit

June 23, 2026

Conditions

BruxismOcclusal Changes

Outcome Measures

Primary Outcomes (1)

  • Change in Center of Force (CoF)

    The Center of Force (CoF) represents the geometric center of the total occlusal force distribution, measured using the T-Scan Novus™ computerized occlusal analysis system (version 10.0.40; Tekscan, Inc., South Boston, MA, USA). CoF values closer to zero indicate greater bilateral occlusal balance. Within-group changes (T0 to T1) and between-group differences were assessed and compared between low-angle (GoGn/SN \< 26°) and normal-angle (GoGn/SN 26-38°) subgroups.

    Baseline (T0) and day 15 post-injection (T1)

Secondary Outcomes (1)

  • Change in Anterior and Posterior Force Percentage

    Baseline (T0) and day 15 post-injection (T1)

Study Arms (1)

Masseter BTX-A Injection (Low-Angle and Normal-Angle Subgroups)

EXPERIMENTAL

Patients with bruxism received bilateral masseter muscle injections of 25 units of botulinum toxin type A (Botox®, Allergan) per side. T-Scan occlusal force measurements were performed at baseline (T0) and day 15 post-injection (T1). Participants were stratified into low-angle and normal-angle subgroups based on GoGn/SN cephalometric angle.

Biological: Botulinum Toxin Type A (BOTOX) Injection

Interventions

Botulinum Toxin Type A (BOTOX) InjectionBIOLOGICAL

Botulinum toxin type A (Botox®, Allergan, Irvine, CA, USA) was injected bilaterally into the masseter muscle at a dose of 25 units per side (50 units total per patient). Injections were performed by a single experienced clinician under sterile conditions using a 30-gauge needle.

Also known as: botox
Masseter BTX-A Injection (Low-Angle and Normal-Angle Subgroups)

Eligibility Criteria

Age18 Years - 40 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64)

You may qualify if:

  • Age 18-40 years
  • Confirmed bruxism diagnosis through self-report and clinical signs
  • Full permanent dentition excluding third molars
  • Angle Class I molar relationship
  • No previous BTX-A injection within 6 months
  • GoGn/SN angle between 18° and 38° on lateral cephalometric radiograph

You may not qualify if:

  • Systemic neuromuscular disorders
  • Known allergy to botulinum toxin or its excipients
  • Pregnancy or breastfeeding
  • Active infection at the injection site
  • Concurrent use of medications known to interact with BTX-A
  • History of orthognathic surgery or prior temporomandibular joint surgery

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Department of Orthodontics, Faculty of Dentistry, Biruni University

Istanbul, Istanbul, 34010, Turkey (Türkiye)

Location

MeSH Terms

Conditions

Bruxism

Interventions

Botulinum Toxins, Type A

Condition Hierarchy (Ancestors)

Tooth DiseasesStomatognathic DiseasesHabitsBehavior

Intervention Hierarchy (Ancestors)

Botulinum ToxinsMetalloendopeptidasesEndopeptidasesPeptide HydrolasesHydrolasesEnzymesEnzymes and CoenzymesMetalloproteasesBacterial ProteinsProteinsAmino Acids, Peptides, and ProteinsBacterial ToxinsToxins, BiologicalBiological Factors

Study Officials

  • Esra Agaoğlu Mogul

    Department of Orthodontics, Faculty of Dentistry, Biruni University

    STUDY CHAIR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Principal Investigator

Study Record Dates

First Submitted

June 23, 2026

First Posted

June 29, 2026

Study Start

February 9, 2026

Primary Completion

May 8, 2026

Study Completion

May 8, 2026

Last Updated

June 29, 2026

Record last verified: 2026-06

Data Sharing

IPD Sharing
Will not share

Individual participant data will not be shared due to patient privacy and ethical restrictions. Data are available from the corresponding author on reasonable request.

Locations

TU(1)