For Peer Review
Association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism
Journal: Journal of Sleep Research Manuscript ID Draft
Manuscript Type: Regular Research Paper Date Submitted by the Author: n/a
Complete List of Authors: Yoshida, Yuya; Showa University, School of Dentistry, Department of Prothodontic
Suganuma, Takeshi; Showa University, School of Dentistry, Department of Prosthodontics
Takaba, Masayuki; Showa Unversity, School of Dentistry, Depatment of Prothodontics
Ono, Yasuhiro; Showa University, School of Dentistry, Department of Prothodontics
Abe, Yuka; Showa University, School of Dentistry, Department of Prosthodontics
Yoshizawa, Shuichiro ; Showa University, School of Dentistry, Department of Prosthodontics
Sakai, Takuro; Showa University, School of Dentistry, Department of Prosthodontics
Yoshizawa, Ayako; Showa University, School of Dentistry, Department of Prosthodontics
Nakamura, Hirotaka; Showa University, School of Dentistry, Department of Prosthodontics
Kawana, Fusae; Yumino Heart Clinic,
Baba, Kazuyoshi; Showa University, School of Dentistry, Department of Prosthodontics
Keywords: Sleep related movement disorder, Diagnosis, Tooth wear, Rhythmic masticatory muscle activity, Orofacial pain, Polysomnograph
For Peer Review
Association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism
Running Head: Clinical signs and symptoms of sleep bruxism
Yuya Yoshida1, Takeshi Suganuma1, Masayuki Takaba1, Yasuhiro Ono1, Yuka Abe1, Shuichiro Yoshizawa1, Takuro Sakai1, Ayako Yoshizawa1, Hirotaka Nakamura1, Fusae Kawana2, Kazuyoshi Baba1
1 Department of Prosthodontics, School of Dentistry, Showa University, 2-1-1 Kitasenzoku, Ohta-ku, Tokyo 145-8515, Japan
2 Yumino Heart Clinic, 3-14-29 Takada, Toshima-ku, Tokyo 171-0033, Japan
CONFLICTS OF INTEREST
The authors have no financial conflicts of interest to declare.
Total number of words: 4170, total number of references: 25
Address correspondence to: Dr. Kazuyoshi Baba
Department of Prosthodontics, School of Dentistry, Showa University 2-1-1 Kitasenzoku, Ohta-ku, Tokyo 145-8515, Japan
Tel: +81-3-3787-1151; Fax: +81-3-3784-7603 E-mail: [email protected] 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
SUMMARY
The aim of this study was to investigate the association between patterns of jaw motor activity during sleep and clinical signs and symptoms of sleep bruxism. A total of 35 university students and staff members participated in this study after providing informed consent. All participants were divided into either an sleep bruxism group (n=21) or a control group (n=14) based on the following clinical diagnostic criteria: 1) reports of tooth-grinding sounds for at least three nights a week during the preceding six months by their sleep partner; 2) presence of tooth attrition with exposed dentin; 3) reports of morning masticatory muscle fatigue or tenderness; and 4) presence of masseter muscle hypertrophy. Video-polysomnography was performed in the sleep laboratory for two nights.
sleep bruxism episodes were measured using masseter electromyography, visually inspected, and then categorized into phasic or tonic episodes. Phasic episodes were further categorized into episodes with or without grinding sounds as evaluated by audio signals. Sleep bruxism subjects with reported grinding sounds had a significantly higher total number of phasic episodes with grinding sounds than subjects without reported grinding sounds or controls (Kruskal-Wallis/Steel-Dwass; p<0.05). Similarly, sleep bruxism subjects with tooth attrition exhibited significantly longer phasic burst durations than those without or controls (Kruskal-Wallis/Steel-Dwass; p<0.05). Furthermore, sleep bruxism subjects with morning masticatory muscle fatigue or tenderness exhibited significantly longer tonic burst durations than those without or controls (Kruskal-Wallis/Steel-Dwass; p<0.05). These results suggest that each clinical sign and symptom of sleep bruxism represents different aspects of jaw motor activity during sleep.
Keywords
Sleep related movement disorder Diagnosis
Tooth wear
Rhythmic masticatory muscle activity Orofacial pain
Polysomnograph 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
INTRODUCTION
In the third edition of the International Classification of Sleep Disorders (ICSD-3), sleep bruxism (SB) is defined as “an oral parafunction characterized by grinding or clenching of the teeth during sleep that is associated with an excessive (intense) sleep arousal activity.” These involuntary masticatory muscle activities may cause and/or accelerate abnormal tooth attrition (Menapace et al., 1994, Abe et al., 2009), fracture of dental restorations and tooth structures (Lin et al., 2012), periodontal disease, or temporomandibular disorders (Clark et al., 1981, Baba et al., 2005, Manfredini and Lobbezoo, 2010), and consequently, SB may deteriorate prognoses after dental treatments. Therefore, to prevent such SB-related clinical problems, accurate diagnosis is necessary.
Although polysomnography (PSG) with simultaneous audio-video recording is considered the gold standard for diagnosis of SB, the associated costs and technical complexity of laboratory-based poly-channel recordings are problematic. For example, PSG recording requires the subject to sleep at a sleep laboratory and to be wired directly to numerous recording devices. In addition, for PSG data to be correctly scored, additional manual recounts by specialists or sleep laboratory technicians are necessary (Rompre et al., 2007, Dutra et al., 2009). Overall, although PSG recordings are useful for research purposes, they have significant limitations in the clinical setting.
Therefore, clinical diagnosis of SB is generally made based on information gathered through medical interviews and clinical examinations, such as reports of tooth grinding sounds during sleep (Tsiggos et al., 2008), orodental findings such as tooth attrition (Gandara and Truelove, 1999), morning symptoms of masticatory muscle pain, fatigue, or stiffness (Rompre et al., 2007), and masseter muscle hypertrophy (Pintado et al., 1997). One important question is whether these signs and symptoms accurately represent SB. To answer this question, we investigated the association between the clinical diagnostic criteria for SB and the frequency of jaw motor events 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
during sleep as evaluated by PSG in a previous study (Yoshizawa et al., 2014). We found that subjects with tooth grinding and attrition had a higher frequency of rhythmic masticatory muscle activity (RMMA) episodes, during sleep than those without. In addition, no difference was found in the frequency of jaw motor episodes regardless of the presence or absence of morning masticatory muscle symptoms and masseter muscle hypertrophy, suggesting that these clinical signs and symptoms could represent distinct physiological components of jaw motor activity during sleep.
However, that study was limited by the small sample size and lack of controls (e.g., those without SB). Therefore, a case-controlled study using a larger study sample was considered necessary to confirm the results.
For these reasons, the aim of this study was to examine whether clinical signs and symptoms are associated with the occurrence of specific types of SB episodes in case and control subjects.
MATERIALS AND METHODS Participants
A total of 40 participants, 24 with possible SB and 16 possible controls based on self-report
(Lobbezoo et al., 2013), were recruited from among undergraduate students, graduate students, and staff at Showa University. After providing informed consent, participants were enrolled based on the following inclusion criteria: 1) between the age of 20 and 35 years; 2) dentulous with bilateral occlusal contacts in the intercuspal position; and 3) presence of a sleep partner. Exclusion criteria were as follows: 1) more than two missing posterior teeth, excluding third molars or the use of a removable prosthesis; 2) use of medication with possible effects on sleep or motor behavior; 3) alcohol or drug abuse; 4) ongoing physical or dental therapy including orthodontic treatment; 5) 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
major neurological or psychiatric disorders; and 6) sleep disorder (e.g., sleep apnea syndrome, narcolepsy).
All participants underwent clinical interviews and examinations regarding the clinical signs and symptoms of SB, followed by laboratory-based PSG with simultaneous audio-video recordings. This study was approved by the Showa University School of Dentistry Ethics Committee (#2010-025; March 30, 2012).
Clinical signs and symptoms of SB
The clinical diagnostic criteria for SB, which were derived from the literature (Dube et al., 2004), consisted of one primary criterion: a history of tooth grinding sounds occurring at least three nights a week for the preceding six months as reported by their sleep partner, and the following three secondary criteria: 1) more than three teeth with dentine exposure caused by attrition; 2) presence of masticatory muscle fatigue or tenderness in the morning; and 3) presence of masseter muscle hypertrophy. All clinical interviews and examinations were conducted by an experienced dentist (YY); the same dentist also determined the presence or absence of all clinical signs and symptoms.
After enrollment, two subjects (one from possible SB, one from possible controls) dropped out from the study due to time conflicts. The clinical diagnosis of SB was made when an individual satisfied the primary criterion or two of the three secondary criteria. All 23 possible SB subjects were clinically diagnosed as having SB, and the remaining 15 subjects who did not meet any of these criteria were assigned to the control group.
PSG recordings
Individuals were studied in the sleep laboratory for two nights. The first night allowed them to adapt to the laboratory setting and permitted us to rule out the presence of sleep disorders. Only 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
data from the second night were used for the analysis. PSG recordings, with surface electrodes, included six electroencephalograms (EEG; C2A1, C3A2, O2A1, O3A2, F2A1, and F3A2), bilateral electrooculograms, an electrocardiogram, and electromyograms (EMG) of the chin/suprahyoid, bilateral masseter, temporalis, and tibialis muscles. Respiration was monitored using a nasal pressure/thermistor sensor and pulse oximeter. All signals were amplified (Embla N7000 PSG amplifier, Natus Neurology Inc., Warwick, RI, USA) and recorded at a sampling rate of 200 Hz, then stored for off-line manual analysis using PSG software (Embla REMbrandt, Natus Neurology Inc.). Audio-video recordings were carried out simultaneously to distinguish SB episodes from nonspecific orofacial activities (Lavigne et al., 1991, Kato et al., 1999) and to recognize tooth grinding sounds associated with SB episodes.
Sleep and SB scoring
According to the guidelines of the American Academy of Sleep Medicine, sleep data were manually scored for each 30-s epoch by an experienced sleep technician (FK). Total sleep time, sleep efficiency, sleep latency, microarousal index, awakening index, and percentage of time spent in each sleep stage were calculated.
Masticatory EMG potentials with amplitudes that exceeded approximately 10% of maximum voluntary contraction were retained for analysis. Nonspecific EMG activity unrelated to SB (e.g., sighing, coughing, somniloquy, or activities related to head/body movements) was removed with the aid of audio-video recordings (Dutra et al., 2009), and then jaw motor episodes were scored into phasic episodes (three EMG bursts or more, each lasting 0.25 to 2.0 s), tonic episodes (EMG burst >2.0 s), or mixed episodes (both types of bursts) (Lavigne et al., 1996).
RMMA was defined as both phasic and mixed episodes and counted separately from isolated tonic episodes (Rompre et al., 2007).
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
Next, the total number of SB episodes per hour, as well as the total number of phasic, tonic, and mixed episodes per hour, were calculated. Regarding phasic episodes, the presence or absence of grinding sounds was also determined with the aid of audio-video inspection. In addition, each mixed episode was divided into phasic and tonic bursts, and the total duration of each type of burst was then calculated. All SB scorings were manually conducted by one of the authors (YY).
The following PSG-based SB diagnostic criteria were applied to each participant: 1) more than four bruxism episodes per hour; 2) more than six bruxism bursts per episode and/or 25 bruxism bursts per hour of sleep; and 3) at least two episodes with grinding sounds (Rompre et al., 2007).
Data from three subjects were excluded because of PSG failure (one from the probable SB group) and the presence of sleep apnea syndrome (one from the probable SB group and one from the probable control group) (Lobbezoo et al., 2013). Overall, data from 35 subjects (18 females, 17 males; mean age ± standard deviation, 26.5 ± 2.5 years) were analyzed. Twenty-one participants who satisfied at least one of the above criteria were definitely diagnosed as having SB, and the remaining 14 who did not meet any of these criteria were categorized as definite controls (Lobbezoo et al., 2013) (Fig. 1).
Statistical analysis
Sleep variables were compared between the SB and control groups using independent-samples t tests or Mann-Whitney U tests with 5% set as the level of significance. SB variables were compared among the three groups (the SB groups with and without clinical signs or symptoms and the control group) using Kruskal-Wallis/Steel-Dwass tests with 5% set as the level of significance.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
RESULTS
Clinical signs and symptoms
The distribution of the clinical signs and symptoms identified in all subjects is summarized in Table 1. Tooth attrition was present in all SB and two control subjects. Muscle hypertrophy was present in seven SB and two control subjects; however, the other three variables were only found in the SB group. Since the original tooth attrition criterion was satisfied by the majority of the SB subjects, we increased the cut-off value for the number of teeth with dentine exposure (from three to a median value of nine). This new criterion identified nine SB subjects as positive.
Reports of tooth grinding (r=0.55, p<0.01) and morning masticatory muscle fatigue or tenderness (r=0.58, p<0.01) were positively correlated with the presence of tooth attrition. The correlation between reports of tooth grinding and morning muscle fatigue or tenderness was also significant (r=0.55, p<0.01). No other significant correlations were found.
Sleep and SB variables
Descriptive statistics of the sleep and SB variables are shown in Tables 2 and 3, respectively.
Regarding the sleep structure, the SB group had lower sleep efficiency than the control group;
however, the majority of the sleep variables were comparable between the two groups. The SB variables were consistently larger in the SB group than in the control group, and phasic episodes most frequently occurred during SB episodes (Table 3). In total, 74% of the SB burst duration was categorized as phasic (Table 3).
Association between SB variables and clinical signs and symptoms
Tooth grinding was reported in 12 of the 21 SB subjects. These subjects tended to exhibit a higher 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
number of RMMA episodes than those without this symptom; however, this trend was not statistically significant. Nonetheless, this group did exhibit a significantly higher number of phasic episodes with grinding sounds identified by PSG than the SB group without reported grinding sounds and the controls (Table 4 and Fig. 2). Those with a higher number of teeth with dentine exposure (larger than nine) had a significantly higher number of RMMA episodes and phasic episodes with grinding sounds, and longer total phasic burst durations (Table 4 and Fig. 3) than the other two groups. Seven out of the 21 SB subjects reported having morning masticatory muscle fatigue or tenderness; these seven subjects exhibited significantly longer tonic burst durations than those without morning muscle fatigue or tenderness and controls (Fig. 4). Finally, muscle hypertrophy was present in 13 SB and two control subjects. This sign was not associated with any of the SB variables.
DISCUSSION
This study should be regarded as a confirmative study of our previous study (Yoshizawa et al., 2014). Clear improvements over the previous study included the establishment of a control group, a larger sample size, and a more detailed investigation of PSG data, such as grinding sound analysis.
Overall, this study reproduced the results of our previous study and provided several new findings as discussed below.
Reports of tooth grinding noises tended to be positively associated with a higher frequency of RMMA episodes; this result, although not statistically significant, was also consistent with those from our previous study (Yoshizawa et al., 2014). However, we did find a significant association between tooth grinding sounds and phasic episodes with grinding sounds, which were recognized by audio-video observations of PSG data. It should be noted that only one-third of the phasic episodes (34%) were associated with grinding sounds as identified by PSG in the SB 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
subjects with grinding sounds reported by their sleep partner. This value decreased to 6% in the SB group without reported grinding sounds. These results suggest that the more frequently grinding sounds occur, the more likely these sounds would be heard by a sleep partner. We also speculate some of phasic episodes without grinding sounds might represent rhythmic clenching without jaw grinding movements (Amemori et al., 2001) and others might be jaw grindings but insufficiently intense to generate grinding sounds. This study did not conduct simultaneous jaw tracking recordings; therefore, this issue should be addressed in future studies.
Since tooth attrition is a cumulative record of both functional and parafunctional tooth wear, the evaluation of tooth attrition to establish a diagnosis of ongoing SB and its severity remains controversial (Johansson et al., 2008, Kato and Lavigne, 2010, Carra et al., 2011). Some studies have reported finding a positive relationship between tooth attrition and self-reported bruxism (Carlsson et al., 1985, Ekfeldt et al., 1990); however, those studies did not differentiate between sleep and waking bruxism. Previous PSG studies, including ours (Abe et al., 2009, Yoshizawa et al., 2014), have reported an association between the presence of tooth attrition and a higher frequency of RMMA, but not isolated tonic episodes. The present study reproduced the results of those studies. In addition, we also found a stronger and more direct association with the frequency of phasic episodes with grinding sounds, with a 4.7-fold difference between SB subjects with and without this variable. As previously stated, this stronger association indicates that phasic episodes with grinding sounds might be representative of jaw grinding movements with intense muscle contraction.
Morning masticatory muscle symptoms are thought to be a type of post-exercise muscle soreness resulting from frequent masticatory muscle contractions during sleep (Svensson et al., 2008). However, we did not find any associations between morning muscle symptoms and the occurrence of RMMA or isolated tonic episodes, which is consistent with our previous study 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
(Yoshizawa et al., 2014). However further investigation of the total tonic burst durations of not only isolated tonic, but also mixed episodes found a significant associated with this symptom. This result suggests that clenching-type SB might contribute to the development of morning symptoms. Since masticatory muscle fatigue or tenderness is reportedly affected by muscle contraction strength and frequency, further quantitative analysis of tonic activity might have captured this association (Svensson et al., 2008). Although morning masticatory muscle symptoms were associated with reports of grinding sounds and tooth attrition, the jaw motor activity of SB subjects with these symptoms was characterized differently.
Masseter muscle hypertrophy was not associated with any of SB variables, which is in agreement with our previous study (Yoshizawa et al., 2014). Although masseter muscle
hypertrophy is often included as a sign for the clinical diagnosis for SB, it has not yet been validated in terms of sensitivity and specificity (Lavigne et al., 1996). The clinical diagnosis of hypertrophy is often accompanied by difficulty in appropriate confirmation due to vague standards, so diagnosis may depend entirely on the evaluations of clinicians. In addition, severe or frequent tooth clenching during wakefulness is known as one of the most important contributors to morphological change such as masseter muscle hypertrophy (Clark et al., 1981, Bas et al., 2010, Kato and Lavigne, 2010). In fact, this clinical sign was also found in our control subjects.
Several limitations should be acknowledged when interpreting the results of this study.
First, we used a convenient sample of dental students and university staff. As such, they might have had background information on clinical signs and symptoms of SB upon enrollment. Actually, no inconsistencies were found between self-reported SB status, clinical SB diagnosis, and PSG SB diagnosis. This suggests that the results may be less generalizable to typical dental patients, to whom clinical diagnostic criteria are utilized. Second, whereas clinical diagnosis is generally made using a combination of clinical variables, in this study, we evaluated each clinical variable
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
separately. Actually, we found significant correlations between reports of grinding sounds, tooth attrition status, and morning muscle symptoms, which suggested that these variables might be observed simultaneously. However, the aim of this study was to investigate the PSG characteristics of SB in relation to indivisual clinical signs and symptoms, not the clinical characteristics of patient groups categorized by validated PSG diagnostic criteria. Therefore, the sensitivity and specificity of the clinical diagnostic criteria should be investigated in a future study.
The results of this study suggest that each of clinical signs and symptoms of SB relates differently to specific patterns of jaw motor activity during sleep. The presence of tooth attrition and reported tooth grinding during sleep can be helpful for predicting an increased number of phasic episodes with grinding sounds. Furthermore, morning masticatory muscle symptoms might be able to predict increased tonic activity, and masseter hypertrophy should be used as secondary criterion for SB diagnosis. Therefore, in dental practice, in consideration of the limitations of each item, the associations identified in this study could help predict the nature of jaw motor activity in patients with SB.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
LEGENDS FIGURE
Fig. 1. Protocol for assignment of recruited participants
Fig. 2. Association between reported grinding sounds and frequency of phasic episodes with grinding sounds
*p <0.05.
SB: sleep bruxism.
Kruskal-Wallis/Steel-Dwass tests were used.
Fig. 3. Association between attrition and total phasic burst duration
*p <0.05.
SB: sleep bruxism.
Kruskal-Wallis tests and Steel-Dwass tests were used.
Fig. 4. Association between morning masticatory muscle symptoms and total tonic burst duration
*p <0.05.
SB: sleep bruxism.
Kruskal-Wallis/Steel-Dwass tests were used.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
TABLES
Table 1. Distribution of clinical signs and symptoms (n=35)
Table 2. Descriptive statistics of the sleep variables
SB: sleep bruxism; REM: rapid eye movement. *p <0.05.
†Mann-Whitney U tests; otherwise, independent-samples t tests were used.
Data are expressed as mean (standard deviation) or median (min-max).
Table 3. Descriptive statistics of the sleep bruxism variables SB: sleep bruxism. *p <0.05.
Data are expressed as the median (min-max).
Mann-Whitney U tests were used.
Table 4. Associations between clinical signs and symptoms and electromyogram activity
Contrasts: a = SB group with clinical signs and symptoms vs. SB group without clinical signs and symptoms; b = SB group without clinical signs and symptoms vs. control group; c = SB group with clinical signs and symptoms vs. control group.
Kruskal-Wallis/Steel-Dwass tests were used.
Data are expressed as the median (min-max).
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
REFERENCES
Abe, S., Yamaguchi, T., Rompre, P. H., De Grandmont, P., Chen, Y. J. and Lavigne, G. J. Tooth wear in young subjects: a discriminator between sleep bruxers and controls? Int. J.
Prosthodont., 2009, 22: 342-50.
Amemori, Y., Yamashita, S., Ai, M., Shinoda, H., Sato, M. and Takahashi, J. Influence of nocturnal bruxism on the stomatognathic system. Part I: a new device for measuring mandibular movements during sleep. J. Oral Rehabil., 2001, 28: 943-9.
Baba, K., Haketa, T., Sasaki, Y., Ohyama, T. and Clark, G. T. Association between masseter muscle activity levels recorded during sleep and signs and symptoms of temporomandibular disorders in healthy young adults. J. Orofac. Pain, 2005, 19: 226-31.
Bas, B., Ozan, B., Muglali, M. and Celebi, N. Treatment of masseteric hypertrophy with botulinum toxin: a report of two cases. Med. Oral Patol. Oral Cir. Bucal., 2010, 15: e649-52.
Carlsson, G. E., Johansson, A. and Lundqvist, S. Occlusal wear. A follow-up study of 18 subjects with extensively worn dentitions. Acta Odontol. Scand., 1985, 43: 83-90.
Carra, M. C., Huynh, N., Morton, P. et al. Prevalence and risk factors of sleep bruxism and wake-time tooth clenching in a 7- to 17-yr-old population. Eur. J. Oral Sci., 2011, 119:
386-94.
Clark, G. T., Beemsterboer, P. L. and Rugh, J. D. Nocturnal masseter muscle activity and the symptoms of masticatory dysfunction. J. Oral Rehabil., 1981, 8: 279-86.
Dube, C., Rompre, P. H., Manzini, C., Guitard, F., De Grandmont, P. and Lavigne, G. J.
Quantitative polygraphic controlled study on efficacy and safety of oral splint devices in tooth-grinding subjects. J. Dent. Res., 2004, 83: 398-403.
Dutra, K. M., Pereira, F. J., Jr., Rompre, P. H., Huynh, N., Fleming, N. and Lavigne, G. J. Oro-facial activities in sleep bruxism patients and in normal subjects: a controlled polygraphic and 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
audio-video study. J. Oral Rehabil., 2009, 36: 86-92.
Ekfeldt, A., Hugoson, A., Bergendal, T. and Helkimo, M. An individual tooth wear index and an analysis of factors correlated to incisal and occlusal wear in an adult Swedish population.
Acta Odontol. Scand., 1990, 48: 343-9.
Gandara, B. K. and Truelove, E. L. Diagnosis and management of dental erosion. J. Contemp. Dent.
Pract., 1999, 1: 16-23.
Johansson, A., Johansson, A. K., Omar, R. and Carlsson, G. E. Rehabilitation of the worn dentition.
J. Oral Rehabil., 2008, 35: 548-66.
Kato, T. and Lavigne, G. J. Sleep Bruxism: A Sleep-Related Movement Disorder. Sleep Med. Clin., 2010, 5: 9-35.
Kato, T., Montplaisir, J. Y., Blanchet, P. J., Lund, J. P. and Lavigne, G. J. Idiopathic myoclonus in the oromandibular region during sleep: a possible source of confusion in sleep bruxism diagnosis. Mov. Disord., 1999, 14: 865-71.
Lavigne, G. J., Rompre, P. H. and Montplaisir, J. Y. Sleep bruxism: validity of clinical research diagnostic criteria in a controlled polysomnographic study. J. Dent. Res., 1996, 75: 546-52.
Lavigne, G. J., Velly-Miguel, A. M. and Montplaisir, J. Muscle pain, dyskinesia, and sleep. Can. J.
Physiol. Pharmacol., 1991, 69: 678-82.
Lin, W. S., Ercoli, C., Lowenguth, R., Yerke, L. M. and Morton, D. Oral rehabilitation of a patient with bruxism and cluster implant failures in the edentulous maxilla: a clinical report. J.
Prosthet. Dent., 2012, 108: 1-8.
Lobbezoo, F., Ahlberg, J., Glaros, A. G. et al. Bruxism defined and graded: an international consensus. J. Oral Rehabil., 2013, 40: 2-4.
Manfredini, D. and Lobbezoo, F. Relationship between bruxism and temporomandibular disorders:
a systematic review of literature from 1998 to 2008. Oral Surgery, Oral Medicine, Oral 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
Pathology, Oral Radiology and Endodontology. 2010, 109: e26-e50.
Menapace, S. E., Rinchuse, D. J., Zullo, T., Pierce, C. J. and Shnorhokian, H. The dentofacial morphology of bruxers versus non-bruxers. Angle Orthod., 1994, 64: 43-52.
Pintado, M. R., Anderson, G. C., Delong, R. and Douglas, W. H. Variation in tooth wear in young adults over a two-year period. J. Prosthet. Dent., 1997, 77: 313-20.
Rompre, P. H., Daigle-Landry, D., Guitard, F., Montplaisir, J. Y. and Lavigne, G. J. Identification of a sleep bruxism subgroup with a higher risk of pain. J. Dent. Res., 2007, 86: 837-42.
Svensson, P., Jadidi, F., Arima, T., Baad-Hansen, L. and Sessle, B. J. Relationships between craniofacial pain and bruxism. J. Oral Rehabil., 2008, 35: 524-47.
Tsiggos, N., Tortopidis, D., Hatzikyriakos, A. and Menexes, G. Association between self-reported bruxism activity and occurrence of dental attrition, abfraction, and occlusal pits on natural teeth. J. Prosthet. Dent., 2008, 100: 41-6.
Yoshizawa, S., Suganuma, T., Takaba, M. et al. Phasic jaw motor episodes in healthy subjects with or without clinical signs and symptoms of sleep bruxism: a pilot study. Sleep Breath, 2014, 18: 187-93.
2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59
For Peer Review
Figures
Fig.1
Participants (n=40)
Clinical signs and symptoms (n=40) Medical interviews and oral examinations
PSG recording (n=38)
Dropout (n=2)
Exception (n=1)
SB group (n=21) Control group (n=14)
Possible SB; n=24, Possible control; n=16
Possible SB; n=23, Possible control; n=15
Sleep and SB scoring (n=37)
Exception (n=2)
* PSG failure
* Presence of sleep apnea syndrome
* Time conflicts
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Fig.2
0 5 10 15 20 25
SB+ SB- Control
*
*
*
Phasic episode with sounds /hr
SB presence SB absence Control
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Fig.3
0 100 200 300 400 500 600
SB+ SB- Control
*
*
*
Phasic burst duration (s)
SB presence SB absence Control
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Fig.4
0 20 40 60 80 100 120 140
SB+ SB- Control
*
*
Tonic burst duration (s)
SB presence SB absence Control
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Tables
Table 1. Distribution of clinical signs and symptoms (n=35)
Presence Presence Absence Absence
Presence 3 0 0 2 Presence
Presence 2 1 1 0 Absence
Absence 1 3 3 3 Presence
Absence 0 2 2 12 Absence
Presence Absence Presence Absence
Reports from sleep partner
Reports of mornig masticatory musclefatigure or tenderness
Tooth attrition Muscle hypertrophy
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Table 2. Descriptive statistics of the sleep variables
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Table 3. Descriptive statistics of the sleep bruxism variables
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
For Peer Review
Table 4. Associations between clinical signs and symptoms and electromyogram activity
Journal of Sleep Research 2
3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58
