Bruxism Induced by Obstructive Sleep Apnoea.

Evaluation of the Relationship Between Upper Airway Volume and the Risk of Bruxism Induced by Obstructive Sleep Apnoea.

The relationship between obstructive sleep apnea (OSA), sleep bruxism, and temporomandibular disorders is becoming clearer, but data on how upper airway volume affects bruxism due to OSA is limited. Recent studies have shown that Cone-Beam Computed Tomography (CBCT) accurately images the upper airway, enabling analysis of its volume and its potential impact on bruxism. CBCT uses low radiation doses, significantly lower than harmful levels, making it a safe method for such assessments. Understanding these relationships can inform clinical practices for managing sleep bruxism, which affects 21% of the global population. The study aims to explore how upper airway volume influences the intensity of sleep bruxism related to OSA.

Study Overview

• Status: Not yet recruiting
• Conditions: Bruxism, Sleep-Related; Sleep Apnea Syndrome, Obstructive; Upper Respiratory Tract Illness
• Intervention / Treatment: Diagnostic test: Upper airway volume assessment using Cone-Beam Computed Tomography (CBCT) and Polysomnography; Diagnostic test: Upper airway volume assessment using Cone-Beam Computed Tomography (CBCT)

Detailed Description

The main objective of the study is to assess the relationship between upper airway volume and sleep bruxism and obstructive sleep apnea. The following null hypothesis was adopted: upper airway volume influences the intensity of sleep bruxism induced by obstructive sleep apnea.

The relationship between obstructive sleep apnea and bruxism during sleep (behavior involving increased activity of the masticatory muscles during sleep) and temporomandibular disorders (a group of diseases and disorders related to the morphology and function of the masticatory system (mainly the temporomandibular joints and masticatory muscles) is becoming increasingly well understood. However, there is a lack of data on the relationship between the three-dimensional volume of the upper airways and sleep bruxism induced by sleep apnea. Recent scientific publications have demonstrated the ability of CBCT (Cone-Beam Computed Tomography) to image the upper airway very accurately in order to examine the minimum cross-section and total volume of the upper airway in three dimensions. 3D imaging using CBCT is a simple, effective, and safe method for accurate analysis of the upper airway, which will help determine the relationship between upper airway volume and bruxism induced by obstructive sleep apnea (OSA). Modern cone beam tomography is characterized by significantly lower doses of electromagnetic radiation, averaging between 0.05 and 0.6 mSv (50-600 µSv). It is estimated that, on average, each person receives a dose of radiation from natural sources of approximately 2.4 mSv (2,400 µSv) per year. Radiation doses in diagnostic imaging, therefore, represent only a fraction of these values. It is important to be aware of what dose of radiation is harmful. It is estimated that negative health effects may occur at doses of around 200 mSv (200,000 µSv), which is significantly higher than that received during modern imaging examinations.

Materials and Methods:

A total of 80 adult volunteers will be recruited for the research project, divided into two groups of 40 each, comprising both sexes, who will give their voluntary and informed consent to participate in the study. The study group will consist of patients with sleep bruxism and obstructive sleep apnoea. The control group will consist of patients with sleep bruxism without obstructive sleep apnoea. First, each potential participant in the project will undergo a clinical and physical examination of the stomatognathic system in accordance with the international DC/TMD guidelines (Diagnostic Criteria for Temporomandibular Disorders) and in accordance with the current international consensus on bruxism at the Temporomandibular Disorders Clinic of the University Dental Centre in Wrocław. The patient will undergo a clinical examination during which systemic diseases and medications taken will be recorded.

The study will also include a range of validated questionnaires assessing psycho-emotional well-being and selected aspects related to the functioning of the stomatognathic system, including the PHQ-9 (Patient Health Questionnaire 9), PSS-10 (Perceived Stress Scale 10), GAD-7 (Generalised Anxiety Disorder 7), SWLS (Satisfaction with Life Scale), SSS-8 (Somatic Symptom Scale 8), MIDAS (The Migraine Disability Assessment Test), JFLS-8 (Jaw Functional Limitation Scale - 8), TMD Pain Screener (Temporomandibular Disorders Pain Screener) and DC/TMD Symptom Questionnaire (Diagnostic Criteria for Temporomandibular Disorders Symptom Questionnaire). In addition, the following validated sleep questionnaires will be used: EPWORTH (Epworth Sleepiness Scale), PSQI (Pittsburgh Sleep Quality Index) and STOP-Bang Questionnaire. The next step will be to refer the patient for CBCT imaging, including measurements of the minimum cross-sectional area and 3D volume of the upper airways. Upper airway measurements will be performed in accordance with the protocol by Fonseca et al. (Fonseca C, Cavadas F, Fonseca P. Upper Airway Assessment in Cone-Beam Computed Tomography for Screening of Obstructive Sleep Apnoea Syndrome: Development of an Evaluation Protocol in Dentistry. JMIR Res Protoc. 2023;12:e41049. doi: 10.2196/41049). The CBCT scan will take place at the University Dental Centre in Wrocław. The patient will then be referred to the Department and Clinic of Diabetology, Hypertension and Internal Medicine at the University Hospital, 213 Borowska Street, Wrocław, for a polysomnography examination. Polysomnography (PSG) is a non-invasive test comprising an EEG (electroencephalogram), ECG (electrocardiogram), EOG (electrooculogram), EMG (electromyogram), assessment of chest and abdominal movements, and measurement of blood oxygen saturation. It is used as the gold standard for diagnosing the severity of sleep apnoea by determining the AHI (Apnoea-Hypopnoea Index) and sleep bruxism by determining the BEI (Bruxism Episode Index). The polysomnography will be performed in accordance with the current guidelines of the American Academy of Sleep Medicine. During PSG, numerous other parameters relating to bodily functions during sleep are also collected. The aforementioned medical facilities possess the necessary equipment, scientific and clinical knowledge and experience to carry out the aforementioned examinations (CBCT: Planmeca Viso G7 CT scanner, Helsinki, Finland; PSG: NOX A1 sleep recorder, Iceland). The collected data will undergo thorough and specialist statistical analysis.

Anticipation Results:

By analyzing the results collected during the study and establishing probable correlations or their absence, it will be possible to understand the relationship between specific disorders and behaviors, and then counteract their development in everyday clinical work with patients with sleep bruxism around the world. According to the latest meta-analysis, this is 21% of the global population (Zieliński G et al. Global Prevalence of Sleep Bruxism and Awake Bruxism in Pediatric and Adult Populations: A Systematic Review and Meta-Analysis. J Clin Med. 22 July 2024;13(14):4259. doi: 10.3390/jcm13144259).

• Study Type: Observational
• Enrollment (Estimated): 80

Contacts and Locations

• Study Contact: Name: Andrzej Małysa, PhD; Phone Number: +48 7717186292; Email: andrzej.malysa@umw.edu.pl
• Study Contact Backup: Name: Mieszko Więckiewicz, Professor MD, PhD, DSc; Phone Number: +48 7717186292; Email: mieszko.wieckiewicz@umw.edu.pl

Study Locations

• Poland
  • Dolny Śląsk
    • Wroclaw, Dolny Śląsk, Poland, 50-425
      • Uniwersyteckie Centrum Stomatologiczne

Participation Criteria

Eligibility Criteria

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

• Sampling Method: Non-Probability Sample

Study Population

A total of 80 adult volunteers will be recruited for the research project, divided into two groups of 40 each, comprising both sexes, who will give their voluntary and informed consent to participate in the study. The study group will consist of patients with sleep bruxism and obstructive sleep apnoea. The control group will consist of patients with sleep bruxism without obstructive sleep apnoea. Participants are arbitrarily selected from a population.

Description

Inclusion Criteria:

• age equal to/greater than 18 years
• moderate or high risk of sleep apnea according to the STOP-Bang questionnaire
• presence of bruxism symptoms in the oral cavity according to the current international consensus on bruxism
• positive history of bruxism during sleep

Exclusion Criteria:

• refusal to participate in the study
• pregnancy
• breastfeeding
• presence of severe mental illness
• alcohol and/or drug addiction
• taking medications that affect the neuromuscular and/or respiratory systems
• severe systemic diseases such as cancer
• severe neurological and autoimmune diseases
• multiple missing teeth
• edentulism in the upper and/or lower jaw

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Study Group; The study group will consist of patients with sleep bruxism and obstructive sleep apnoea. Participants will be examined based on the standardised international protocol Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Study participants will complete the following validated questionnaires assessing their psycho-emotional state and selected aspects related to the function of the stomatognathic system, including PHQ-9, PSS-10, GAD-7, SWLS, SSS-8, MIDAS, JFLS-8, TMD Pain Screener and DC/TMD Symptom Questionnaire (Diagnostic Criteria for Temporomandibular Disorders Symptom Questionnaire). In addition, the following validated sleep questionnaires will be used: EPWORTH ,PSQI and STOP-Bang Questionnaire. Subsequently, CBCT computed tomography will be performed along with polysomnography to determine the parameters of upper airway volume and sleep apnea.	Diagnostic test: Upper airway volume assessment using Cone-Beam Computed Tomography (CBCT) and Polysomnography; Patients in the study group will undergo validated questionnaires assessing psycho-emotional well-being and selected aspects related to the functioning of the stomatognathic system, upper airway volume assessment using CBCT tomography and polysomnography.
Control Group; The control group will consist of patients with sleep bruxism. Participants will be examined based on the standardised international protocol Diagnostic Criteria for Temporomandibular Disorders (DC/TMD). Study participants will complete the following validated questionnaires assessing their psycho-emotional state and selected aspects related to the function of the stomatognathic system, including PHQ-9, PSS-10, GAD-7, SWLS, SSS-8, MIDAS, JFLS-8, TMD Pain Screener and DC/TMD Symptom Questionnaire (Diagnostic Criteria for Temporomandibular Disorders Symptom Questionnaire). In addition, the following validated sleep questionnaires will be used: EPWORTH ,PSQI and STOP-Bang Questionnaire. Subsequently, CBCT computed tomography will be performed to determine the parameters of upper airway volume.	Diagnostic test: Upper airway volume assessment using Cone-Beam Computed Tomography (CBCT); Patients in the control group will undergo validated questionnaires assessing psycho-emotional well-being and selected aspects related to the functioning of the stomatognathic system, upper airway volume assessment using CBCT tomography.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The relationship between obstructive sleep apnea and bruxism during sleep.	Relationship between the three-dimensional volume of the upper airways and sleep bruxism induced by sleep apnea, determined by CBCT and polysomnography.	01.04.2026-31.11.2026

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Relationship between masticatory muscle pain and depression assessed by Patient Health Questionnaire.	Each participant will fill in Patient Health Questionnaire - 9. PHQ-9 total score for the nine items ranges from 0 to 27.Scores of 5, 10, 15, and 20 represent cutpoints for mild, moderate, moderately severe and severe depression, respectively.	01.04.2026-31.12.2026
Relationship between masticatory muscle pain and anxiety assessed by Generalized Anxiety Disorder -7.	Each participant will fill in Generalized Anxiety Disorder -7 that consists of 7 items. Total score ranges 0-21 points. Scores of 5, 10, and 15 are taken as the cut-off points for mild, moderate and severe anxiety, respectively.	01.04.2026-31.12.2026
Relationship between masticatory muscle pain and perceived stress assessed by Perceived Stress Scale.	Each participant will fill in Perceived Stress Scale -10. Scores are obtained by reversing the scores on the four positive items, e.g., 0=4, 1=3, 2=2, etc. and then summing across all 10 items. Items 4,5, 7, and 8 are the positively stated items. It can range from 0 to 40. Scores ranging from 0-13 would be considered low stress,14-26 would be considered moderate stress, 27-40 would be considered high perceived stress.	01.04.2026-31.12.2026
Relationship between masticatory muscle pain and satisfaction with life assessed by Satisfaction With Life Scale.	Each participant will fill in Satisfaction With Life Scale which consist of five questions with 5 possible answers. Total score range is 35. Higher score represents higher life satisfaction. Score ranging from 5-9 as considered as extremly dissatisfied with life, 10-14 dissatisfied, 15-19 slightly dissatisfied, 20-24 slightly satisfied, 25-29 satisfied, 30-35 extremely satisfied.	01.04.2026-31.12.2026
Relationship between bruxism and sleep quality assessed by Pittsburgh Sleep Quality Index - a self-report questionnaire that assesses sleep quality over a 1-month time interval.	Each participant will fill in Pittsburgh Sleep Quality Index. The measure consists of 19 individual items, creating 7 components that produce one global score ranging from 0 to 21, where lower scores mean better sleep quality.	01.04.2026-31.12.2026
Relationship between bruxism and apnea risk assessed by STOP-Bang.	Each participant will fill in STOP-Bang questionnaire. The total score ranges from 0 to 8. The lower the score is, the lower the risk of occurrence Obstructive Sleep Apnea (OSA).	01.04.2026-31.12.2026
Relationship between bruxism and headache impact assessed by Migraine Disability Assessment questionnaire.	Each participant will fill in Migraine Disability Assessment questionnaire. Scoring includes adding the total number of days from questions 1-5. Grading includes: grade I (little or no disability) 0-5 days, grade II (mild disability) 6-10 days, grade III (moderate disability) 11-20 days, grade IV (severe disability) more than 21 days.	01.04.2026-31.12.2026
Relationship between bruxism and sleep apnea (OSA) by Epworth Sleepiness Scale	Each participant will fill Epworth Sleepiness Scale (ESS), which is a validated 8-item self-administered questionnaire used to measure average daytime sleepiness and the probability of falling asleep in common situations, ranging from 0 (never) to 3 (high chance) per item. A total score of 11 or higher indicates excessive daytime sleepiness, potentially suggesting sleep disorders like apnea.	01.04.2026-31.12.2026

Collaborators and Investigators

• Sponsor: Wroclaw Medical University
• Investigators: Principal Investigator: Mieszko Adam Więckiewicz, Professor MD, PhD, DSc, Wroclaw Medical University

Publications and helpful links

General Publications

• Błaszczyk B, Waliszewska-Prosół M, Więckiewicz M, Poręba R, Niemiec P, Przegrałek J, Martynowicz H. Sleep bruxism (SB) may be not associated with obstructive sleep apnea (OSA): A comprehensive assessment employing a systematic review and meta-analysis. Sleep Med Rev. 2024 Dec;78:101994. doi: 10.1016/j.smrv.2024.101994. Epub 2024 Aug 22. PMID: 39182463.
• Oksenberg A, Arons E. Sleep bruxism related to obstructive sleep apnea: the effect of continuous positive airway pressure. Sleep Med. 2002 Nov;3(6):513-5. doi: 10.1016/s1389-9457(02)00130-2.

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): October 1, 2026
• Study Completion (Estimated): November 1, 2026

Study Registration Dates

• First Submitted: March 30, 2026
• First Submitted That Met QC Criteria: March 30, 2026
• First Posted (Actual): April 6, 2026

Study Record Updates

• Last Update Posted (Actual): April 6, 2026
• Last Update Submitted That Met QC Criteria: March 30, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Sleep Apnea; Bruxism, Sleep-Related
• Additional Relevant MeSH Terms: Stomatognathic Diseases; Nervous System Diseases; Mental Disorders; Tooth Diseases; Respiratory Tract Diseases; Respiration Disorders; Sleep Wake Disorders; Apnea; Sleep Disorders, Intrinsic; Dyssomnias; Parasomnias; Bruxism; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Sleep Bruxism; Diagnostic Techniques and Procedures; Diagnosis; Monitoring, Physiologic; Polysomnography
• Other Study ID Numbers: SUBK.B160.25.003 (Other Identifier: Wroclaw Medical University)

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