Oral appliances reduce masticatory muscle activity-sleep bruxism metrics independently of changes in heart rate variability.

OBJECTIVES: Sleep bruxism (SB) is associated with physiological activities including sympathetic autonomic system dominance and sleep micro-arousal. While oral appliances (OA) are used to prevent SB harmful effects, the influence of OAs physiological mechanisms during sleep is unknown. The aim of this study is to assess whether heart rate variability (HRV) changes, as a marker of autonomic nervous system activity, would be associated with the OA mechanism of action on SB using occlusal splint (OS) and mandibular advancement splint (MAS). MATERIALS AND METHODS: A retrospective analysis, from data previously collected in 21 participants with SB (25.6 ± 4.5 years) with polysomnographic recordings, was done. HRV data were compared between a reference night (no-device) and ones during which OS or MAS was used in a crossover study design. Rhythmic masticatory muscle activity (RMMA) index was compared between nights. HRV was evaluated using autoregressive model analysis for three sections: baseline (distance from RMMA), immediately before, and after RMMA period. RESULTS: A significant reduction in RMMA index, when wearing OA during sleep, was observed (P < 0.01), but was not associated with HRV parameters change. HRV significantly changed after RMMA onset for nights with OA during non-REM sleep in comparison with baseline (P < 0.02). CONCLUSIONS: The usage of OAs for SB participants reduced RMMA, but most likely independently of changes in HRV linked to the mechanism associated with SB genesis. CLINICAL RELEVANCE: Wearing OA seems to reduce grinding noise and protect from dental injuries but does not seem to influence SB genesis.

The effect of nocturnal wear of dentures on the sleep quality: a systematic review and meta-analysis.

PURPOSE: The effect of nocturnal wear of denture on sleep quality and integrity is still not well understood. Therefore, this systematic review was conducted to provide evidence on this topic. METHODS: Electronic searches were conducted from 1964 up to September 2015, using MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials. Only publications in English or French, in which sleep quality of edentate adult individuals wearing dentures at night was compared to those not wearing were included in the review. Random effects models were used to pool the effect sizes. RESULTS: A total of 10 studies were included in the systematic review and 5 in the meta-analysis. No statistically significant difference between sleeping with denture and without denture was found for the Apnea-Hypopnea Index (AHI; Standard Mean Difference = -0.60, 95 % CI -1.67-0.47; Z = -1.10; p = 0.27). However, there was considerable heterogeneity in the studies included in the meta-analysis (Tau2 = 1.34; Q-value = 59.32, df = 4 (P < 0.0001); I2 = 93.3 %). When results from randomized controlled trials (RCTs) were pooled in subgroup analyses of AHI, there was a tendency towards favoring sleeping without dentures (P = 0.059) and no evidence of heterogeneity between studies (Tau2 = 0.000; Q-value = 0.06, df = 1 (P = 0.80); I2 = 0.000 %). CONCLUSION: The current evidence suggests that there is no difference in the sleep quality and integrity of individuals wearing or not wearing their denture during sleep. However, the results of randomized controlled trials favoring sleeping without dentures and the likely presence of bias in the previous studies indicate the need for further randomized controlled trials for the development of clinical guideline.

Females with sleep bruxism show lower theta and alpha electroencephalographic activity irrespective of transient morning masticatory muscle pain.

AIMS: To investigate the hypothesis that the presence of transient morning masticatory muscle pain in young, healthy sleep bruxers (SBr) is associated with sex-related differences in sleep electroencephalographic (EEG) activity. METHODS: Data on morning masticatory muscle pain and sleep variables were obtained from visual analog scales and a second night of polysomnographic recordings. Nineteen normal control (CTRL) subjects were age- and sex-matched to 62 tooth-grinding SBr. Differences in sleep macrostructure (stage distribution and duration, number of sleep-stage shifts), number of rhythmic masticatory muscle activity (RMMA) events÷ hour, and EEG activity were analyzed blind to subject status. The influence of pain and gender in SBr and CTRL subjects was assessed with the Fisher's exact test, Mann-Whitney U test, two-sample t test, and analysis of variance (ANOVA). RESULTS: Low-intensity morning transient orofacial pain was reported by 71% of SBr, with no sex difference. RMMA event frequency was higher in SB than CTRL subjects (4.5÷hour vs 1.3÷hour; P < .001). SBr had fewer sleep-stage shifts, irrespective of sex or pain status. Female SBr had significantly lower theta and alpha EEG activity compared to female CTRL subjects (P = .03), irrespective of pain. CONCLUSION: Female SBr had lower theta and alpha EEG activity irrespective of transient morning pain.

Sleep Quality and Comfort Reported by Sleep Bruxism Individuals Wearing the Occlusal Splint and Mandibular Advancement Splint: Revisiting Two Crossover Studies.

PURPOSE: To assess (1) whether an occlusal splint (OS) or mandibular advancement splint (MAS) allowed better sleep quality and was more comfortable in individuals with sleep bruxism (SB); and (2) the relationship between sleep quality, comfort, and reduction in RMMA related to SB. MATERIALS AND METHODS: Polysomnographic data from 21 SB subjects (mean ± SD age 25.6 ± 4.5 years) collected in two previous studies were compared. Morning self-reports on sleep quality and comfort of the oral device, polysomnographic data, and RMMA index data from no-device nights were compared to nights using an OS or MAS. The reduction ratio of the RMMA index was calculated for both devices. A responder to the oral device was identified when the RMMA index was less than 2 and when it showed a reduction of at least 50% from the no-device control night. RESULTS: Self-reports for sleep quality and comfort of the oral device showed a mild advantage of the OS when compared to the MAS (r2 = 0.47, r2 = 0.32; P ≤ .01). In responders, the MAS induced a greater reduction in the RMMA index (P = .03) than the OS. CONCLUSIONS: In the short term, the comfort of the oral device seemed to influence sleep quality in SB individuals. However, despite the slightly higher degree of comfort offered by the OS, the MAS induced a greater effect on the RMMA index. Int J Prosthodont 2022;36:138-147. doi: 10.11607/ijp.7525.

Dental sleep-related conditions and the role of oral healthcare providers: A scoping review.

Dental sleep medicine as a discipline was first described about a quarter of a century ago. Snoring, obstructive sleep apnea, sleep bruxism, xerostomia, hypersalivation, gastroesophageal reflux disease, and orofacial pain were identified as dental sleep-related conditions. This scoping review aimed to: i) identify previously unidentified dental sleep-related conditions; and ii) identify the role of oral healthcare providers in the prevention, assessment, and management of dental sleep-related conditions in adults. A systematic literature search was conducted in PubMed, Embase.com, Web of Science, and Cochrane. Studies that reported an actual or likely role of oral healthcare providers in the prevention, assessment, and/or management of sleep-related conditions were included. Of the 273 included studies, 260 were on previously listed dental sleep-related conditions; the other 13 were on burning mouth syndrome. Burning mouth syndrome was therefore added to the list of dental sleep-related conditions for the first aim and categorized into sleep-related orofacial pain. For the second aim, the role of oral healthcare providers was found to be significant in the prevention, assessment, and management of obstructive sleep apnea and sleep bruxism; in the assessment and management of snoring, sleep-related orofacial pain, and oral dryness; and in the assessment of sleep-related gastroesophageal reflux condition.

Adeno-tonsillectomy and rapid maxillary distraction in pre-pubertal children, a pilot study.

INTRODUCTION: When both narrow maxilla and moderately enlarged tonsils are present in children with obstructive sleep apnea, the decision of which treatment to do first is unclear. A preliminary randomized study was done to perform a power analysis and determine the number of subjects necessary to have an appropriate response. Thirty-one children, 14 boys, diagnosed with OSA based on clinical symptoms and polysomnography (PSG) findings had presence of both narrow maxillary complex and enlarged tonsils. They were scheduled to have both adeno-tonsillectomy and RME for which the order of treatment was randomized: group 1 received surgery followed by orthodontics, while group 2 received orthodontics followed by surgery. Each child was seen by an ENT, an orthodontist, and a sleep medicine specialist. The validated pediatric sleep questionnaire and PSG were done at entry and after each treatment phase at time of PSG. Statistical analyses were ANOVA repeated measures and t tests. RESULTS: The mean age of the children at entry was 6.5 ± 0.2 years (mean ± SEM). Overall, even if children presented improvement of both clinical symptoms and PSG findings, none of the children presented normal results after treatment 1, at the exception of one case. There was no significant difference in the amount of improvement noted independently of the first treatment approach. Thirty children underwent treatment 2, with an overall significant improvement shown for PSG findings compared to baseline and compared to treatment 1, without any group differences. CONCLUSION: This preliminary study emphasizes the need to have more than subjective clinical scales for determination of sequence of treatments.

Associations between sleep-disordered breathing symptoms and facial and dental morphometry, assessed with screening examinations.

INTRODUCTION: Chronic snoring is considered abnormal in a pediatric population. This disorder is often attributed to enlarged tonsils and adenoids, but multiple anatomic obstructions should also be considered. Facial and dental morphometry associations with various sleep-disordered breathing symptoms were investigated at an orthodontic clinic. METHODS: Parents or guardians were asked to complete a 4-part questionnaire on behalf of their children (n = 604; <18 years of age), including medical and dental history, bruxism and temporomandibular disorder habits, sleep and daytime behavior, and sleep duration and quality. All subjects underwent a clinical screening assessment by the same orthodontist to identify standard dental, skeletal, functional, and esthetic factors. RESULTS: In contrast to sleep-disordered breathing or sleep apnea in adults, which is predominantly associated with obesity, sleep-disordered breathing symptoms in this pediatric cohort were primarily associated with adenotonsillar hypertrophy, morphologic features related to a long and narrow face (dolichofacial, high mandibular plane angle, narrow palate, and severe crowding in the maxilla and the mandible), allergies, frequent colds, and habitual mouth breathing. CONCLUSIONS: Because of the recognized impact of pediatric snoring on children's health, the determination of these good predictors can help in preventing and managing sleep-disordered breathing. If a health professional notices signs and symptoms of sleep-disordered breathing, the young patient should be referred to a sleep medicine specialist in conjunction with an orthodontist if there are dentoskeletal abnormalities.

Effects of nocturnal wearing of dentures on the quality of sleep and oral-health-related quality in edentate elders with untreated sleep apnea: a randomized cross-over trial.

STUDY OBJECTIVES: This study aims to assess whether the nocturnal wear of dentures has an effect on the quality of sleep and oral-health-related quality of life of the edentulous elderly with untreated sleep apnea. METHODS: A single-blind randomized cross-over design with two sequences and two periods was used. Participants (n = 77) were randomly assigned either to sequence 1 (nocturnal wear followed by nocturnal nonwear of the denture for 30-30 days) or sequence 2 (nocturnal nonwear followed by nocturnal wear of denture for 30-30 days). The primary sleep outcome was the quality of sleep, assessed through sleep fragmentation measured as Apnea-Hypopnea Index (AHI) and respiratory arousal from portable polysomnography. Secondary outcomes were daytime sleepiness, sleep quality (Pittsburgh Sleep Quality Index, PSQI) and oral-health-related quality of life measured by validated questionnaires. RESULTS: The mean paired difference in AHI scores for the period of wearing versus not wearing dentures at night was small 1.0 event per hour (p = 0.50; 95% confidence interval (CI) = -2.0 to 4.1). The mean respiratory arousal index was higher when wearing dentures at night than when not wearing dentures at night, with a mean paired difference of 2.3 events per hour (p = 0.05; 95% CI = 0.0 to 4.6). No difference in sleepiness and PSQI were noted. Wearing dentures at night resulted in a statistically significantly higher mean score of psychological discomfort when compared to not wearing dentures at night. CONCLUSIONS: The results provide some support to usual practice guidelines to remove dentures at night in edentulous elders suffering from sleep apnea. CLINICAL TRIAL REGISTRATION: NCT01868295.

Phenotypes of responders to mandibular advancement device therapy in obstructive sleep apnea patients: A systematic review and meta-analysis.

Mandibular advancement device (MAD) therapy is the most commonly used non-continuous positive airway pressure (CPAP) treatment for obstructive sleep apnea (OSA). Although OSA patients prefer MAD over CPAP, on average over one third have minimal or no major reduction in OSA severity with MAD therapy. Improved understanding of responder characteristics (or "phenotypes") to MAD may facilitate more efficient use of limited medical resources and optimize treatment efficacy. The aim of this review is to describe the baseline phenotypic characteristics of responders to MAD therapy in OSA patients. Pubmed, Web of Science, EMBASE, Scopus were searched for eligible studies published until Feb 2019. A total of 650 studies were identified. 41 studies were included in this review and meta-analysis. The quality of the studies was assessed using the risk of bias assessment tool for non-randomized studies (RoBANS). Based on meta-analysis, the responders to MAD therapy had certain clinical phenotypic characteristics: lower age (95% CI: -4.55 to -1.62, p < 0.00001), female (95% CI: 0.56 to 0.91, p = 0.006), lower body mass index (95% CI: -2.80 to -1.11, p < 0.00001), smaller neck circumference (95% CI: -1.57 to -0.52, p < 0.00001), lower apnea-hypopnea index (95% CI: -7.23 to -1.89, p < 0.00001), a retracted maxilla and mandible, a narrower airway and a shorter soft palate than non-responders. The above-mentioned phenotypic responder characteristics provides useful information for the clinician when considering prescribing MAD therapy for OSA patients.

Orthodontic expansion treatment and adenotonsillectomy in the treatment of obstructive sleep apnea in prepubertal children.

STUDY OBJECTIVE: Rapid maxillary expansion and adenotonsillectomy are proven treatments of obstructive sleep apnea (OSA) in children. Our goal was to investigate whether rapid maxillary expansion should be offered as an alternative to surgery in select patients. In addition, if both therapies are required, the order in which to perform these interventions needs to be determined. DESIGN: Prepubertal children with moderate OSA clinically judged to require both adenotonsillectomy and orthodontic treatment were randomized into 2 treatment groups. Group 1 underwent adenotonsillectomy followed by orthodontic expansion. Group 2 underwent therapies in the reverse sequence. SUBJECTS: Thirty-two children (16 girls) in an academic sleep clinic. METHOD: Clinical evaluation and polysomnography were performed after each stage to assess efficacy of each treatment modality. RESULTS: The 2 groups were similar in age, symptoms, apnea-hypopnea index, and lowest oxygen saturation. Two children with orthodontic treatment first did not require subsequent adenotonsillectomy. Thirty children underwent both treatments. Two of them were still symptomatic and presented with abnormal polysomogram results following both therapies. In the remaining 28 children, all results were significantly different from those at entry (P = 0.001) and from single therapy (P = 0.01), regardless of the order of treatment. Both therapies were necessary to obtain complete resolution of OSA. CONCLUSION: In our study, 87.5% of the children with sleep-disordered breathing had both treatments. In terms of treatment order, 2 of 16 children underwent orthodontic treatment alone, whereas no children underwent surgery alone to resolve OSA. Two children who underwent both treatments continued to have OSA.

Orthodontics treatments for managing obstructive sleep apnea syndrome in children: A systematic review and meta-analysis.

A small maxilla and/or mandible may predispose children to sleep-disordered breathing, which is a continuum of severity from snoring to obstructive sleep apnea. Preliminary studies have suggested that orthodontic treatments, such as orthopedic mandibular advancement or rapid maxillary expansion, may be effective treatments. The aim is to investigate the efficacy of orthopedic mandibular advancement and/or rapid maxillary expansion in the treatment of pediatric obstructive sleep apnea. Pubmed, Medline, Embase, and Internet were searched for eligible studies published until April 2014. Articles with adequate data were selected for the meta-analysis; other articles were reported in the qualitative assessment. Data extraction was conducted by two independent authors. A total of 58 studies were identified. Only eight studies were included in the review; of these, six were included in the meta-analysis. The research yielded only a small number of studies. Consequently, any conclusions from the pooled diagnostic parameters and their interpretation should be treated carefully. Although the included studies were limited, these orthodontic treatments may be effective in managing pediatric snoring and obstructive sleep apnea. Other related health outcomes, such as neurocognitive and cardiovascular functions have not yet been systematically addressed. More studies are needed with larger sample size, specific inclusion and exclusion criteria and standardized data reporting to help establish guidelines for the orthodontic treatment of pediatric obstructive sleep apnea.

Sleep bruxism, snoring, and headaches in adolescents: short-term effects of a mandibular advancement appliance.

OBJECTIVES: Sleep bruxism (SB) frequently is associated with other sleep disorders and pain concerns. Our study assesses the efficacy of a mandibular advancement appliance (MAA) for SB management in adolescents reporting snoring and headache (HA). METHODS: Sixteen adolescents (mean age, 14.9±0.5) reporting SB, HA (>1d/wk), or snoring underwent four ambulatory polysomnographies for baseline (BSL) and while wearing MAA during sleep. MAA was worn in three positions (free splints [FS], neutral position [NP], and advanced to 50% of maximum protrusion [A50]) for 1 week each in random order (FS-NP-A50 or NP-A50-FS; titration order, NP-A50). Reports of HA were assessed with pain questionnaires. RESULTS: Overall, sleep variables did not differ across the four nights. SB index decreased up to 60% with MAA in A50 (P=.004; analysis of variance). Snoring was measured as the percentage of sleep time spent snoring. The subgroup of snorers (n=8) showed significant improvement with MAA (-93%; P=.002). Initial HA intensity was reported at 42.7±5/100 mm, showing a decreasing trend with MAA (-21% to -51%; P=.07). CONCLUSION: Short-term use of an MAA appears to reduce SB, snoring, and reports of HA. However, interactions between SB, breathing during sleep, and HA as well as the long-term effectiveness and safety of MAA in adolescents need further investigation.

Sleep bruxism and oromandibular myoclonus in rapid eye movement sleep behavior disorder: a preliminary report.

OBJECTIVE: We aimed to compare rhythmic masticatory muscle activity typical of sleep bruxism and oromandibular myoclonus (OMM) during rapid eye movement (REM) sleep in patients with idiopathic REM sleep behavior disorder (iRBD) and in Parkinson disease (PD) patients with RBD (PD-RBD). METHODS: Sleep polygraphic data were collected from 9 age-matched controls and 28 patients (mean±standard error of the mean, 66.0±1.7 y) with a clinical and sleep laboratory diagnosis of RBD. Patients were divided into two groups: 13 patients with iRBD and 15 patients with PD-RBD. Rhythmic masticatory muscle activity, a marker of sleep bruxism, and OMM were scored blind to subject's diagnosis from jaw electromyographic recordings during sleep. RESULTS: The rhythmic masticatory muscle activity index was significantly higher during REM sleep in iRBD subjects compared to controls (P<.01) and was significantly higher during non-REM (NREM) sleep in both subject groups compared to controls (P < or = .03). A positive sleep laboratory diagnosis of sleep bruxism was made in 25% of all patients. In iRBD, patients had more OMM during REM sleep than controls (2.4 times higher; P=.01). CONCLUSION: In the presence of a high frequency of rhythmic masticatory muscle activity during REM sleep, RBD may be suspected and further neurologic assessment is recommended.

Comparison of various treatments for sleep bruxism using determinants of number needed to treat and effect size.

PURPOSE: Sleep bruxism (SB) is associated with temporomandibular pain, headaches, tooth wear, and disruption of the bed partner's sleep. The aim of this report was to compare SB treatments from various experimental studies to guide the selection of a treatment for a large sample size study. MATERIALS AND METHODS: After a literature search, randomized controlled studies of 7 pharmacologic treatments and 3 oral devices were included. The number needed to treat (NNT) was calculated from raw data from the sleep laboratory at the Hôpital du Sacré-Coeur, Montréal or from published articles when sufficient data were available. The effect size (ES) was calculated for all included studies. In the most effective treatments, the NNT ranged from 1 to 4, while a high ES was above 0.8. RESULTS: The treatments with the best NNT and ES results were the mandibular advancement device (MAD) and clonidine. The NNT (+/-95% CI) and ES were 2.2 (1.4 to 5.3) and 1.5 for the MAD, and 3.2 (1.7 to 37.3) and 0.9 for clonidine, respectively. An NNT of 3.8 (1.9 to -69.4) and an ES of 0.6 were observed with the occlusal splint, with a reduction of 42% in the SB index. NNT could not be calculated for clonazepam, although the ES was 0.9. CONCLUSION: Although the NNT and ES results seem to indicate that the MAD and clonidine are the most promising experimental treatments, both treatments were associated with side effects (ie, discomfort for the MAD; REM suppression and morning hypotension for clonidine). The occlusal splint and clonazepam seem to be acceptable short-term alternatives, although further longitudinal, large sample size randomized controlled trials in SB management are needed.