Self-reported sleep bruxism and mortality in 1990-2020 in a nationwide twin cohort.

BACKGROUND: The association of sleep bruxism with mortality has not been studied. OBJECTIVES: Altogether 12 040 subjects from the nationwide Finnish twin cohort were included in the analyses. We examined whether self-reported sleep bruxism is associated with increased risk of mortality, and if so, whether the effect is independent of known common risk factors. The time span of the follow-up was 30 years. METHODS: Cox proportional hazards regression models (Hazard Ratios and their 95% Confidence Intervals) adjusted by age, sex and covariates were used to assess the effect of baseline bruxism status in 1990 on future mortality in 1990-2020. RESULTS: The risk of mortality among all participants (n = 12 040), independent of missing covariates and adjusted by age and sex, was 40% higher in weekly bruxers than in never bruxers (HR 1.40, 95% CI 1.16-1.68, p < .001). However, when adjusted by all studied covariates, (n = 11 427) the risk was no longer observed (HR 1.04, 95% CI 0.86-1.25, p = .717). Despite the overall lack of between bruxism and mortality after adjustment for covariates, we examined the cause-specific risks for major cause-of-death groups. There were no substantial associations of weekly bruxism with major disease outcomes by the fully adjusted hazard ratios for them. CONCLUSION: Bruxism does not kill-in line with its definition of being rather a behaviour (with all its phenotypes) than a disease.

Assessment of awake bruxism by a novel bruxism screener and ecological momentary assessment among patients with masticatory muscle myalgia and healthy controls.

BACKGROUND: Bruxism is a masticatory muscle activity occurring during sleep or wakefulness, involving grinding and clenching of teeth and/or jaw bracing. As yet, the aetiology, epidemiology and consequences of awake bruxism (AB) are largely unknown. OBJECTIVES: The aims of the study were to AB behaviours using a novel bruxism screener (BruxScreen) questionnaire part and Ecological Momentary Assessment (EMA; BruxApp©) on AB behaviours, and to investigate AB's prevalence among masticatory muscle myalgia patients and non-patients. METHODS: Altogether, 115 participants (masticatory myalgia patients referred to a specialist clinic (n = 67) and non-patients (n = 46)) filled in a bruxism screener questionnaire to report bruxism behaviours and jaw symptoms. A selection of both groups did a week-long EMA (patients n = 12, non-patients n = 11) to report AB behaviours. The chi-squared test was used to determine group differences in categorical variables. A logistic regression model was fitted to study the probability of AB. RESULTS: According to BruxScreen, bruxism behaviours and jaw symptoms were more frequent in patients than in non-patients (p < .001). Based on EMA, 14.6% of the behaviour in patients was tooth clenching; for non-patients, this was 0.5% (p < .000). Relaxed muscles were reported by patients and non-patients at 20.6% and 56.4%, respectively (p < .021). Logistic regression, adjusted by age and sex, revealed that patients reported AB 5 times more often than non-patients (OR 4.8, 95% CI 2.1-11.2). CONCLUSION: Awake bruxism behaviours are significantly more frequent in masticatory muscle myalgia patients than non-patients and associate with frequent bruxism-related symptoms. Self-reported teeth clenching seems to be the most significant sign of AB behaviour.

Translation and cultural adaptation of the Standardized Tool for the Assessment of Bruxism (STAB) and the Bruxism Screener (BruxScreen): A 12-step guideline.

BACKGROUND: Recently, the Standardized Tool for the Assessment of Bruxism (STAB) and the bruxism screener (BruxScreen) have been developed for use in research and clinical settings. OBJECTIVE: As to ascertain high-quality use of both instruments worldwide, it was our aim to develop a guideline for the translation and cultural adaptation of the STAB and the BruxScreen. METHODS AND RESULTS: This paper describes a 12-step guideline for the translation and cultural adaptation of the STAB and the BruxScreen. A format of a translation log is provided as well. Besides, a website has been created for the guidance of translation teams. CONCLUSION: Following the 12 steps, new language versions of the STAB and the BruxScreen will be ready for further testing (reliability, validity, responsiveness and interpretability) and, ultimately, application in research and clinics around the world.

Awake bruxism in temporomandibular disorders patients referred to tertiary care: A retrospective study on its assessment and TMD management.

BACKGROUND: Bruxism is defined as a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. Bruxism can occur during sleep (sleep bruxism, SB) or during wakefulness (awake bruxism, AB). To date, the effect of AB on the purported negative consequences of bruxism has remained unclear. OBJECTIVES: The assessment of AB, its relation to temporomandibular disorders (TMD) treatment modalities, and their possible outcomes were investigated among TMD patients resistant to treatment in primary care and referred to a tertiary care clinic. METHODS: The records of 115 patients were studied. Patients were referred to the Head and Neck Centre, Department of Oral and Maxillofacial Diseases, Helsinki University Central Hospital, for TMD treatment between 2017 and 2020. The data derived from the eligible patients' records included the following: background data (age and sex), referral data (reason and previous treatment), medical background (somatic and psychiatric), clinical and possible radiological diagnoses at a tertiary care clinic, treatment modalities for masticatory muscle myalgia, bruxism assessment, its possible treatment modalities and their outcomes, and overall management outcome. We analysed the outcomes of single treatment modalities and combined groups of modalities. For the demographic data, the Chi-squared test and Fischer's Exact test were used to determine the associations between the categorical variables. A Sankey-diagram was used to describe the flow of treatment. RESULTS: Temporomandibular joint-pain-dysfunction syndrome (K07.60) was the most frequent single reason to refer a patient to tertiary care (17.4%). At referral, men had myalgia (M79.1) significantly more often (p = .034) than women. Similarly, men had depression (p = .002) more often and other psychiatric diagnoses (p = .034). At tertiary care, the presence of AB was assessed in 53.9%, and self-reported AB was recorded in 48.7%. In patients with possible AB, those who were prescribed neuropathic pain medication showed significantly less improvement in symptoms (p = .021) than those who underwent splint therapy (p = .009). Overall, half of the patients showed overall improvement in their TMD symptoms from the treatment combinations. CONCLUSION: Despite several treatment modalities, only half of the patients showed improvement in their symptoms in the present study. A standardised assessment method encompassing all factors contributing to bruxism behaviours and their consequences is suggested.

The bruxism screener (BruxScreen): Development, pilot testing and face validity.

BACKGROUND: To assess awake and sleep bruxism, the Standardised Tool for the Assessment of Bruxism (STAB) is currently being developed. The STAB will be a comprehensive tool for the detailed assessment of bruxism behaviour itself as well as of its possible consequences, causes, and comorbid conditions. OBJECTIVE: Since the STAB cannot fully meet the 'A4 principle' for a bruxism assessment tool, i.e., being Accurate (reliable and valid), Applicable (feasible), Affordable (cost-effective), and Accessible (suitable for everyday clinical use), the Bruxism Screener (BruxScreen) has been developed to be used in large-scale epidemiological research projects and, especially, in general, dental practices. METHODS: The BruxScreen consists of two parts: a questionnaire (BruxScreen-Q) to be completed by patients, and a clinical assessment form (BruxScreen-C) to be completed by dentists. RESULTS: This paper describes the development of the BruxScreen and provides the outcomes of the pilot testing phase and the face validity assessment (i.e. that the first impressions of the tool indicate that it adequately reflects the construct to be measured). CONCLUSION: The resulting BruxScreen is considered ready for more profound psychometric testing in the general dental setting.

Research routes on awake bruxism metrics: Implications of the updated bruxism definition and evaluation strategies.

BACKGROUND: With time, due to the poor knowledge on it epidemiology, the need to focus on awake bruxism as a complement of sleep studies emerged. OBJECTIVE: In line with a similar recent proposal for sleep bruxism (SB), defining clinically oriented research routes to implement knowledge on awake bruxism (AB) metrics is important for an enhanced comprehension of the full bruxism spectrum, that is better assessment and more efficient management. METHODS: We summarised current strategies for AB assessment and proposed a research route for improving its metrics. RESULTS: Most of the literature focuses on bruxism in general or SB in particular, whilst knowledge on AB is generally fragmental. Assessment can be based on non-instrumental or instrumental approaches. The former include self-report (questionnaires, oral history) and clinical examination, whilst the latter include electromyography (EMG) of jaw muscles during wakefulness as well as the technology-enhanced ecological momentary assesment (EMA). Phenotyping of different AB activities should be the target of a research task force. In the absence of available data on the frequency and intensity of wake-time bruxism-type masticatory muscle activity, any speculation about the identification of thresholds and criteria to identify bruxers is premature. Research routes in the field must focus on the improvement of data reliability and validity. CONCLUSIONS: Probing deeper into the study of AB metrics is a fundamental step to assist clinicians in preventing and managing the putative consequences at the individual level. The present manuscript proposes some possible research routes to advance current knowledge. At different levels, instrumentally based and subject-based information must be gathered in a universally accepted standardised approach.

Standardised Tool for the Assessment of Bruxism.

OBJECTIVE: This paper aims to present and describe the Standardised Tool for the Assessment of Bruxism (STAB), an instrument that was developed to provide a multidimensional evaluation of bruxism status, comorbid conditions, aetiology and consequences. METHODS: The rationale for creating the tool and the road map that led to the selection of items included in the STAB has been discussed in previous publications. RESULTS: The tool consists of two axes, specifically dedicated to the evaluation of bruxism status and consequences (Axis A) and of bruxism risk and etiological factors and comorbid conditions (Axis B). The tool includes 14 domains, accounting for a total of 66 items. Axis A includes the self-reported information on bruxism status and possible consequences (subject-based report) together with the clinical (examiner report) and instrumental (technology report) assessment. The Subject-Based Assessment (SBA) includes domains on Sleep Bruxism (A1), Awake Bruxism (A2) and Patient's Complaints (A3), with information based on patients' self-report. The Clinically Based Assessment (CBA) includes domains on Joints and Muscles (A4), Intra- and Extra-Oral Tissues (A5) and Teeth and Restorations (A6), based on information collected by an examiner. The Instrumentally Based Assessment (IBA) includes domains on Sleep Bruxism (A7), Awake Bruxism (A8) and the use of Additional Instruments (A9), based on the information gathered with the use of technological devices. Axis B includes the self-reported information (subject-based report) on factors and conditions that may have an etiological or comorbid association with bruxism. It includes domains on Psychosocial Assessment (B1), Concurrent Sleep-related Conditions Assessment (B2), Concurrent Non-Sleep Conditions Assessment (B3), Prescribed Medications and Use of Substances Assessment (B4) and Additional Factors Assessment (B5). As a rule, whenever possible, existing instruments, either in full or partial form (i.e. specific subscales), are included. A user's guide for scoring the different items is also provided to ease administration. CONCLUSIONS: The instrument is now ready for on-field testing and further refinement. It can be anticipated that it will help in collecting data on bruxism in such a comprehensive way to have an impact on several clinical and research fields.

Self-reported sleep bruxism in 1990 and 2011 in a nationwide twin cohort: Evidence of trait persistence and genetic liability.

BACKGROUND: Due to different assessment modes employed, a clear picture of the prevalence of sleep bruxism across time cannot be formed. Moreover, studies on the persistent or fluctuating nature of sleep bruxism have yielded divergent and even contradictory results. The aim of the present study was to evaluate in a nationwide twin cohort whether self-reported sleep bruxism was correlated longitudinally, pairwise and cross-twin over a 20-year period. OBJECTIVES: Self-reported bruxism was assessed in 1990 and 2011 by mailed questionnaires in the Finnish Twin Cohort study of same-sex twins born 1945-1957. METHODS: We assessed the phenotypic stability over time for all participating individuals (n = 4992). Among zygosity verified pairs (n = 516 MZ and n = 837 DZ), we estimated the cross-sectional zygosity correlations and the zygosity-specific cross-twin cross-time correlations. RESULTS: Reported bruxism appeared rather persistent over time without significant difference regarding zygosity. The overall phenotypic longitudinal correlation was 0.540 and somewhat higher in men (0.596) than in women (0.507). Pairwise trait correlations in 1990 and 2011 were higher in MZ than in DZ pairs. The cross-twin cross-time correlations were higher in MZ twins than in DZ twins, but less than the cross-sectional MZ and DZ pairwise correlations. CONCLUSIONS: The higher correlation of reported sleep bruxism in the cross-twin cross-time analyses in MZ than in DZ pairs implies a genetic background for bruxism persistence. Also, bruxism over time in individual twins appears to be fairly persistent and somewhat higher in men than women.

The development of the Standardised Tool for the Assessment of Bruxism (STAB): An international road map.

This paper summarises the background reasoning and work that led to the selection of the items included in the Standardised Tool for the Assessment of Bruxism (STAB), also introducing the list of items. The instrument is currently being tested for face validity and on-field comprehension. The underlying premise is that the different motor activities included in the bruxism spectrum (e.g. clenching vs. grinding, with or without teeth contact) potentially need to be discriminated from each other, based on their purportedly different aetiology, comorbidities and potential consequences. Focus should be on a valid impression of the activities' frequency, intensity and duration. The methods that can be used for the above purposes can be grouped into strategies that collect information from the patient's history (subject-based), from the clinical assessment performed by an examiner (clinically based) or from the use of instruments to measure certain outcomes (instrumentally based). The three strategies can apply to all aspects of bruxism (i.e. status, comorbid conditions, aetiology and consequences). The STAB will help gathering information on many aspects, factors and conditions that are currently poorly investigated in the field of bruxism. To this purpose, it is divided into two axes. Axis A includes the self-reported information on bruxism status and potential consequences (subject-based report) together with the clinical (examiner report) and instrumental assessment (technology report). Axis B includes the self-reported information (subject-based report) on factors and conditions that may have an etiological or comorbid role for bruxism. This comprehensive multidimensional assessment system will allow building predictive model for clinical and research purposes.

Bruxism definition: Past, present, and future - What should a prosthodontist know?

STATEMENT OF PROBLEM: The definition of bruxism has evolved, and the dental profession needs to align with the terminologies adopted in the current literature of sleep and orofacial pain medicine. PURPOSE: The purpose of this review was to discuss the recent evolution of bruxism concepts and the implications for changing the definition that is currently used by the prosthodontic community. MATERIAL AND METHODS: A historical perspective on the evolution of the definition of bruxism, as well as a systematic literature review on the validity of polysomnography (PSG)-based criteria for sleep bruxism diagnosis to detect the presence of clinical consequences, is presented. Selected articles were read in a structured Population, Intervention, Comparison, Outcome (PICO) format to answer the question "If a target population with conditions such as tooth wear, dental implant complications, and temporomandibular disorders (P) is diagnosed with sleep bruxism by means of PSG (I) and compared with a population of nonbruxers (C), is the occurrence of the condition under investigation (that is, the possible pathologic consequences of sleep bruxism) be different between the 2 groups (O)?" RESULTS: Eight studies were eligible for the review, 6 of which assessed the relationship between PSG-diagnosed sleep bruxism and temporomandibular disorder pain, while the other 2 articles evaluated the predictive value of tooth wear for ongoing PSG-diagnosed sleep bruxism and the potential role of sleep bruxism in a population of patients with failed dental implants. Findings were contradictory and not supportive of a clear-cut relationship between sleep bruxism assessed based on available PSG criteria and any clinical consequence. The literature providing definitions of bruxism as a motor behavior and not pathology has been discussed. CONCLUSIONS: The bruxism construct has shifted from pathology to motor activity with possibly even physiological or protective relevance. An expert panel including professionals from different medical fields published 2 consecutive articles focusing on the definition of bruxism, as well as an overview article presenting the ongoing work to prepare a Standardized Tool for the Assessment of Bruxism (STAB) to reflect the current bruxism paradigm shift from pathology to behavior (that is, muscle activity). As such, dental practitioners working in the field of restorative dentistry and prosthodontics are encouraged to appraise this evolution.

Research routes on improved sleep bruxism metrics: Toward a standardised approach.

A recent report from the European Sleep Research Society's task force "Beyond AHI" discussed an issue that has been a long-term subject of debate - what are the best metrics for obstructive sleep apnoea (OSA) diagnosis and treatment outcome assessments? In a similar way, sleep bruxism (SB) metrics have also been a recurrent issue for >30 years and there is still uncertainty in dentistry regarding their optimisation and clinical relevance. SB can occur alone or with comorbidities such as OSA, gastroesophageal reflux disorder, insomnia, headache, orofacial pain, periodic limb movement, rapid eye movement behaviour disorder, and sleep epilepsy. Classically, the diagnosis of SB is based on the patient's dental and medical history and clinical manifestations; electromyography is used in research and for complex cases. The emergence of new technologies, such as sensors and artificial intelligence, has opened new opportunities. The main objective of the present review is to stimulate the creation of a collaborative taskforce on SB metrics. Several examples are available in sleep medicine. The development of more homogenised metrics could improve the accuracy and refinement of SB assessment, while moving forward toward a personalised approach. It is time to develop SB metrics that are relevant to clinical outcomes and benefit patients who suffer from one or more possible negative consequences of SB.

Medications and addictive substances potentially inducing or attenuating sleep bruxism and/or awake bruxism.

Bruxism is a repetitive jaw-muscle activity characterised by clenching or grinding of the teeth and/or by bracing or thrusting of the mandible. It can occur during sleep, indicated as sleep bruxism, or during wakefulness, indicated as awake bruxism. Exogenous risk indicators of sleep bruxism and/or awake bruxism are, among others, medications and addictive substances, whereas also several medications seem to have the potential to attenuate sleep bruxism and/or awake bruxism. The objective of this study was to present a narrative literature on medications and addictive substances potentially inducing or aggravating sleep bruxism and/or awake bruxism and on medications potentially attenuating sleep bruxism and/or awake bruxism. Literature reviews reporting evidence or indications for sleep bruxism and/or awake bruxism as an adverse effect of several (classes of) medications as well as some addictive substances and literature reviews on medications potentially attenuating sleep bruxism and/or awake bruxism were used as starting point and guidelines to describe the topics mentioned. Additionally, two literature searches were established on PubMed. Three types of bruxism were distinguished: sleep bruxism, awake bruxism and non-specified bruxism. Generally, there are insufficient evidence-based data to draw definite conclusions concerning medications and addictive substances inducing or aggravating sleep bruxism and/or awake bruxism as well as concerning medications attenuating sleep bruxism and/or awake bruxism. There are insufficient evidence-based data to draw definite conclusions concerning medications and addictive substances inducing or aggravating sleep bruxism and/or awake bruxism as well as concerning medications attenuating sleep bruxism and/or awake bruxism.

Signal acquisition and analysis of ambulatory electromyographic recordings for the assessment of sleep bruxism: A scoping review.

BACKGROUND: Ambulatory electromyographic (EMG) devices are increasingly being used in sleep bruxism studies. EMG signal acquisition, analysis and scoring methods vary between studies. This may impact comparability of studies and the assessment of sleep bruxism in patients. OBJECTIVES: (a) To provide an overview of EMG signal acquisition and analysis methods of recordings from limited-channel ambulatory EMG devices for the assessment of sleep bruxism; and (b) to provide an overview of outcome measures used in sleep bruxism literature utilising such devices. METHOD: A scoping review of the literature was performed. Online databases PubMed and Semantics Scholar were searched for studies published in English until 7 October 2020. Data on five categories were extracted: recording hardware, recording logistics, signal acquisition, signal analysis and sleep bruxism outcomes. RESULTS: Seventy-eight studies were included, published between 1977 and 2020. Recording hardware was generally well described. Reports of participant instructions in device handling and of dealing with failed recordings were often lacking. Basic elements of signal acquisition, for example amplifications factors, impedance and bandpass settings, and signal analysis, for example rectification, signal processing and additional filtering, were underreported. Extensive variability was found for thresholds used to characterise sleep bruxism events. Sleep bruxism outcomes varied, but typically represented frequency, duration and/or intensity of masticatory muscle activity (MMA). CONCLUSION: Adequate and standardised reporting of recording procedures is highly recommended. In future studies utilising ambulatory EMG devices, the focus may need to shift from the concept of scoring sleep bruxism events to that of scoring the whole spectrum of MMA.

Correlates and genetics of self-reported sleep and awake bruxism in a nationwide twin cohort.

BACKGROUND: Sleep bruxism (SB) and awake bruxism (AB) have been considered different entities, although co-occurrence between them has been shown. While genetic factors have a marked influence on phenotypic variance in liability to SB, this remains unclear for AB. AIM: To examine the degree of co-occurrence of SB and AB, and whether they have common correlates and also twin similarity of SB and AB bruxism traits by zygosity and sex. METHODS: A questionnaire was mailed to all twins born 1945-1957 in Finland in 2012 (n = 11 766). Age and sex adjusted logistic regression models were used. Twin similarity was assessed using polychoric correlations, and crosstwin-crosstrait correlations were computed. RESULTS: The response rate was 72% (n = 8410). Any SB was reported by 14.8% and ≥ 3 nights weekly by 5.0%. Percentages for any AB were 18.4% and 6.3%, respectively. There was substantial co-occurrence (29.5%) between SB and AB, and several shared correlates were found. For SB, the polychoric intra-class correlation was 0.366 in monozygotic (MZ) and 0.200 in dizygotic (DZ) pairs, without gender difference. A twofold crosstwin-crosstrait correlation was observed in MZ twins compared to DZ twins. CONCLUSIONS: The risk factor profiles of SB and AB were largely but not entirely similar. The higher correlation in MZ than in DZ pairs suggests the influence of genetic factors on both SB and AB. The higher crosstwin-crosstrait correlation in MZ than in DZ pairs suggests some degree of genetic influences shared by SB and AB.

Temporomandibular disorders, pain in the neck and shoulder area, and headache among musicians.

BACKGROUND: Uncertainties still exist about the role of playing musical instruments on the report of musculoskeletal complaints and headache. OBJECTIVES: To evaluate the prevalence of and risk indicators for symptoms of temporomandibular disorders, pain in the neck or shoulder, and headache among musicians. METHODS: A questionnaire was distributed among 50 Dutch music ensembles. RESULTS: The questionnaire was completed by 1470 musicians (response rate 77.0%). Of these, 371 musicians were categorised as woodwind players, 300 as brass players, 276 as upper strings players, 306 as vocalists and 208 as controls; nine musicians had not noted their main instrument. The mean age was 41.6 years (standard deviation [SD] 17.2), and 46.5% were male. Irrespective of instrumentalist group, 18.3% of the musicians reported TMD pain, 52.5% reported pain in the neck and shoulder area, and 42.5% reported headache. Of the functional complaints, 18.3% of the musicians reported TMJ sounds, whereas a jaw lock or catch on opening or on closing was reported by 7.1% and 2.4%, respectively. TMD pain was associated with playing a woodwind instrument, whereas pain in the neck and shoulder was associated with playing the violin or viola. For each complaint, oral behaviours were found as risk indicator, supplemented by specific risk indicators for the various complaints. CONCLUSIONS: The current finding that pain-related symptoms varied widely between instrumentalist groups seems to reflect the impact of different instrument playing techniques. Playing a musical instrument appears not the primary aetiologic factor in precipitating a functional temporomandibular joint problem.

Towards a Standardized Tool for the Assessment of Bruxism (STAB)-Overview and general remarks of a multidimensional bruxism evaluation system.

The aim of the present paper was to give an overview of the general project and to present the macrostructure of a comprehensive multidimensional toolkit for the assessment of bruxism, viz. a bruxism evaluation system. This is a necessary intermediate step that will be detailed in a successive extended publication and will ultimately lead to the definition of a Standardized Tool for the Assessment of Bruxism (STAB) as the final product. Two invitation-only workshops were held during the 2018 and 2019 General Session & Exhibition of the International Association for Dental Research (IADR) meetings. Participants of the IADR closed meetings were split into two groups, to put the basis for a multidimensional evaluation system composed of two main axes: an evaluation Axis A with three assessment domains (ie subject-based, clinically based and instrumentally based assessment) and an aetiological/risk factors Axis B assessing different groups of factors and conditions (ie psychosocial assessment; concurrent sleep and non-sleep conditions; drug and substance use or abuse; and additional factors). The work of the two groups that led to the identification of different domains for assessment is summarised in this manuscript, along with a road map for future researches. Such an approach will allow clinicians and researchers to modulate evaluation of bruxism patients with a comprehensive look at the clinical impact of the different bruxism activities and aetiologies. The ultimate goal of this multidimensional system is to facilitate the refinement of decision-making algorithms in the clinical setting.

Weight gain may affect mandibular advancement device therapy in patients with obstructive sleep apnea: a retrospective study.

PURPOSE: The aim was to analyze whether or not weight gain influences the treatment outcome of patients with obstructive sleep apnea (OSA) treated with mandibular advancement devices (MAD). METHODS: As a part of a follow-up study among OSA patients treated with MAD in primary oral health care, a group of 28 patients reporting worsening of daytime or nighttime symptoms of OSA was given closer examination. Altogether, 21 subjects had a complete set of recordings and were enrolled into the study. RESULTS: Only three subjects had lost weight during the study period. The mean weight gain of 3.6 kg ± 7.1 kg was significant (p = 0.035). According to linear regression, weight gain was independently significantly associated with lower mean peripheral oxygen saturation 92.4 (SD 1.8 (% per hour) (p = 0.019)) and lowest oxygen saturation 80.1 (SD 7.2 (%) (p = 0.024)) scores. CONCLUSIONS: Weight gain is detrimentally associated with MAD treatment in patients with OSA. These findings suggest that regular follow-up by an experienced dentist is advisable to assess for possible worsening of OSA. Patient support to encourage weight control may be an important adjunct to MAD treatment for OSA.