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Article

Relationship between Oral Parafunctional and Postural Habits and the Symptoms of Temporomandibular Disorders: A Survey-Based Cross-Sectional Cohort Study Using Propensity Score Matching Analysis

by
Susumu Abe
1,
Fumiaki Kawano
1,
Yoshizo Matsuka
2,
Taeko Masuda
1,
Toshinori Okawa
1 and
Eiji Tanaka
3,*
1
Department of Comprehensive Dentistry, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
2
Department of Stomatognathic Function and Occlusal Reconstruction, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
3
Department of Orthodontics and Dentofacial Orthopedics, Graduate School of Biomedical Sciences, Tokushima University, Tokushima 770-8504, Japan
*
Author to whom correspondence should be addressed.
J. Clin. Med. 2022, 11(21), 6396; https://doi.org/10.3390/jcm11216396
Submission received: 28 September 2022 / Revised: 25 October 2022 / Accepted: 26 October 2022 / Published: 28 October 2022
(This article belongs to the Section Dentistry, Oral Surgery and Oral Medicine)
Browse Figure
Review Reports Versions Notes

Abstract

:
Temporomandibular disorders (TMDs) are a multifactorial joint disease of the masticatory system. The possible etiological factors involved in the onset and progression of TMDs include oral parafunctional habits (OPFHs) and postural habits (PHs). However, little information is available on the association between OPFHs and PHs and a predisposition to TMDs. Thus, to investigate whether the presence of OPFH and PH predisposes individuals to TMDs, a survey-based cross-sectional cohort study of self-reported TMD was performed. A total of 2292 patients with TMD were recruited for the survey. Through one-to-one propensity score matching, 166 patients with and without sleep bruxism (SB) were selected. The SB group had a significantly higher risk of masticatory muscular pain or fatigue than the non-SB group (p = 0.018). Furthermore, the SB group without other OFPHs and PHs did not show a significantly higher risk of TMD symptoms than the non-SB group. Diurnal clenching and bad posture also affect the stomatognathic system, causing pain or fatigue; however, it did not result in TMDs in patients without any OPFHs and PHs. This implies that OPFHs and PHs may increase the risk of TMD symptoms in coexistence with other habits.

1. Introduction

Temporomandibular disorders (TMDs) are a collective term used to describe pain and functional disturbance of the masticatory system [1,2]. Masticatory system pain and disturbance affect oral health-related quality of life [3]. Furthermore, prolonged pain may affect the overall quality of life of the patient [4]. Thus, clinicians should aim for rapid elimination of TMD-related pain to allow for improvement in masticatory function.
According to the Diagnostic Criteria for TMD (DC/TMD) Axis I, TMDs can be divided into pain-related TMDs including masticatory muscle disorders and arthralgia, and intra-articular disorder including disc displacement with or without reduction and mouth opening limitation and osteoarthritis [5]. Epidemiological surveys have shown that TMD is the second most common musculoskeletal disorder that causes pain and disability [6,7] and that musculoskeletal pain occurs in 2–12% of the population [8,9,10], while 10% of the population reported severe symptoms [11]. In a large population study, tenderness of the TMJ and masticatory muscle was observed in 5% and 15% of the population, respectively [12]; however, these symptoms were self-reported by approximately 4% and 6–8% of the patients, respectively [13,14]. The reported prevalence of TMD symptoms and signs may differ widely depending on the method of examination, diagnostic criteria, age, and patient sample selection [15,16,17]. The commonly used treatments for muscular and arthrogenous TMDs are clarified into four types: non-invasive management modalities including occlusal splint, medications, orthotics, and physical therapy; minimally invasive modalities including arthrocentesis, arthroscopy, and intra-articular injections of corticosteroids or hyaluronic acid; invasive surgical modalities including arthroplasty, osteotomy, and osteodistraction; and salvage procedures including total joint replacement [18,19].
Numerous factors can be considered in the etiology of TMDs. Oral parafunctional habits (OPFHs), such as bruxism, diurnal clenching, and thumb sucking, are common and usually have negligible effects on the stomatognathic apparatus [20]. Sleep bruxism (SB) is a movement disorder characterized by repetitive masticatory muscle activity during sleep, and it could be associated with myofascial pain and arthralgia [21]. However, when the activity exceeds the individual resistance threshold or the host’s adaptive capacity decreases, it may cause damage to the dentition, muscles, and TMJ [22]. Several researchers have suggested that OPFHs are a possible etiological factor in the progression of TMDs in growing populations [22,23,24,25]. Furthermore, postural habits (PHs), such as bad posture and sleeping in face down position, are considered indicative of a potential TMD [26,27]. However, little information is available on the association between OPFHs and PHs and a predisposition to TMDs.
Thus, to investigate whether the presence of OPFH and PH predisposes to TMDs, we performed a survey-based cross-sectional cohort study of self-reported TMD among outpatients who visited the Temporomandibular Joint Clinic of Tokushima University Hospital. We aimed to assess the prevalence of self-reported subjective symptoms indicative of TMD and their correlation with OPFHs and PHs associated with the onset and progression of TMDs.

2. Materials and Methods

2.1. Participants

Outpatients with the chief complaint of TMD symptoms who visited the Temporomandibular Joint Clinic at Tokushima University Hospital between April 2010 and September 2021 were recruited. The inclusion criteria for the patients were age >12 years and at least one TMD symptom according to the DC/TMD [5]. The exclusion criteria were uncertain symptoms of TMD; orofacial pain, such as trigeminal neuralgia; toothache; and pain of dental origin.
The Ethics Committee of Tokushima University Hospital approved the study, and written informed consent was obtained from each patient after sufficient explanation of the research purposes (No. 2279-4).

2.2. Questionnaire

All participants were asked to fill out a unique self-reported questionnaire, including items on TMD symptoms, general and oral health, OPFHs and PHs, and some sociodemographic issues. The answer alternatives to all questions were “yes” or “no”, except for items 9 and 14 (Table 1). All patients answered the prepared 21 items in the self-reported questionnaire before the clinical examination. Of the 21 items, 6 items evaluated the present TMD symptoms for the patients, and the remaining included the past medical history or present/past OPFH and PH. In addition, multiple-choice questions regarding the following topics were added to the questionnaire: TMD symptoms (TMJ pain during various mandibular movements (item 1); masticatory muscle pain and fatigue (item 2); difficulty in mouth opening (item 3); TMJ sounds, such as clicking or popping (item 4); frequent headaches and stiff shoulder (item 5); and joint luxation (item 6)), and OPFH and PH (SB (item 16), diurnal grinding or clenching (DC) (item 17), chin on hand (CH) (item 18), face down (FD) (item 19), and bad posture (BP) (item 20)). Furthermore, two items in the questionnaire about previous TMJ treatment (item 9) and chewing side (item 13) with three answer choices were included. Patients were asked to grade two items on “maximum present pain related to this symptom (item 7)” and “degree of daily hindrance related to this symptom (item 8)”. These were rated on a visual analog scale (VAS) with a 100 mm straight horizontal line anchored by descriptors at each end. For “maximum present pain related to this symptom”, which measured painful experiences, the descriptor was “no pain” on the left end and “worst pain” on the right end; for the “degree of daily hindrance related to this symptom”, it was “not at all” on the left and “hardest time” on the right end.

2.3. Setting of Outcomes

The clinical outcomes were set as the present TMD symptoms, which included “TMJ pain during various mandibular movements (item 1)”, “masticatory muscle pain and fatigue (item 2)”, “difficulty in mouth opening (item 3)”, “TMJ sounds, such as clicking or popping (item 4)”, “frequent headaches and stiff shoulder (item 5)”, and “joint luxation (item 6)” from answers of alternatively self-reported questionnaires.

2.4. Statistical Analysis

In the present study, the estimated propensity score of each patient was used to perform individual matching analysis to determine whether OPFH and PH were present. Statistical analysis was performed using SPSS 27.0 (SPSS Inc., Chicago, IL, USA). To calculate the propensity score, a logistic regression model was fitted for each symptom and the patients’ constitution, including age, sex, habits, and history. To evaluate the effect of OPFH and PH on TMD symptoms, the estimated propensity score is required to calculate C-statistics, which is represented by the area under the receiver operating characteristic (ROC) curve and is an indicator for evaluating the goodness of fit [28]. Each patient who had an OPFH or PH was matched with a patient who had no habits with the closest estimated propensity on the logit scale within a specified range (≤0.2 of the pooled standard deviation of estimated logits) as a caliper using a specific OPFH or PH. The propensity score was calculated in the absence of other habits except for the targeted habit.
Fisher’s exact test was used to compare the six present TMD symptoms between the groups with and without OPFHs and PHs. Logistic regression analysis for each TMD symptom was performed in propensity-matched patients to analyze the odds ratios and 95% confidence intervals with reference to the absence of OPFHs and PHs. The two VAS scales for pain and daily hindrance were compared between the presence and absence of each habit using the Mann–Whitney U test.
In the present study, two different methods were used to analyze the effect of OPFHs and PHs: (1) all items, including other OPFHs and PHs except for targeted habits were used, and (2) patients without other OPFHs and PHs were selected to investigate the effect of targeted habits on the onset and progression of TMD symptoms.

3. Results

Of 2367 outpatients, 2292 patients with TMD (639 males and 1653 female) were recruited for the survey using the self-reported questionnaire (Figure 1). The remaining 75 patients who did not fill in the questionnaire items, responded to an indefinite answer, or were below 12 years of age were excluded. Because this analysis focused on each OPFH or PH, one-to-one propensity score matching was performed for each habit to patient history.
Table 2 shows the demographic and clinical characteristics of TMD patients with and without SB. Nine items, including age, medical history of TMD, orthodontic treatment experience, nervousness, hobby, and involvement in sports, and four OPFHs were significantly different between TMD groups with and without SB before propensity score matching (Table 2-(1)). As these items were regarded as confounding factors, we performed propensity score matching to remove these factors. A total of 904 patients with and without SB were selected, and the C-statistic for goodness of fit was calculated using the area under the ROC curve. The computed value was 0.683 in the propensity score model. After propensity score matching, patient distributions were closely balanced (Table 2-(2)). It was observed that the values for all items did not differ significantly between the TMD patients with and without SB.
To examine whether SB affects TMD symptoms, patients without other OPFHs and PHs were included (Table 3). A total of 675 patients had no OPFHs or PHs regardless of SB presence. Significant differences in age and habitual chewing side were found between the patients with and without SB (Table 3). Through one-to-one propensity score matching, 166 patients with and without SB were selected. The C-statistic for goodness of fit in the propensity score model was calculated as 0.620.
Table 4 shows the results of the logistic regression analysis of TMD symptoms involving SB presence in the propensity-matched group in comparison with the non-SB group. The SB group had a significantly higher risk of masticatory muscular pain or fatigue compared with the non-SB group (odds ratio = 1.523; 95% confidence interval, 1.074–2.159; p = 0.018), including medical history, OPFHs, and PHs. However, the degree of maximum pain of daily hindrance did not differ significantly between the SB and non-SB groups, regardless of masticatory muscle pain or fatigue. Furthermore, the SB group without other OFPHs and PHs showed no significantly higher risk of TMD symptoms than the non-SB group (Table 4).
For other OFPHs or PHs except SB, the demographic and clinical characteristics of TMD patients with and without DC, CH, FD, or BP were evaluated (Tables S1–S4). Before propensity score matching, the results indicated significant differences in items 5 to 7 between TMD patients with and without DC, CH, FD, or BP. After propensity score matching, patient distributions were closely balanced between TMD patients with and without each OPFH or PH. Furthermore, to identify the single habit as the causative factor for TMD, single-targeted habits, except the other OFPHs and PHs, were analyzed (Tables S5–S8). For each single targeted habit (DC, CH, FD, or BP), the demographic and clinical characteristics of TMD patients without other OFPHs or PHs, except for each single targeted habit, before and after propensity score matching. Before propensity score matching, items 3 to 7 showed significant differences between the presence and absence of each single targeted habit. However, there were no significant differences between the presence and absence of each single targeted habit after propensity score matching. All C-statistics for goodness of fit were calculated around 0.700 in the propensity score model. Notably, the DC group had a significantly higher risk of jaw pain (odds ratio = 1.372; 95% confidence interval, 1.063–1.770; p = 0.015), masticatory pain or fatigue (odds ratio = 1.477; 95% confidence interval, 1.100–1.982; p = 0.009), and headache or shoulder stiffness (odds ratio = 1.509; 95% confidence interval, 1.203–1.894; p < 0.001) than the non-DC group (Table 4). Furthermore, the DC group had significantly higher maximum pain and daily hindrance than the non-DC group (p = 0.003 and p = 0.010, respectively). However, patients with TMD without other OPFHs and PHs, except for DC, showed no significantly higher risk of TMD symptoms (Table 4). The BP group had a significantly higher risk of headache or shoulder stiffness (odds ratio = 1.599; 95% confidence interval, 1.278–2.002; p < 0.001) than the non-BP group (Table 4). Furthermore, TMD patients without other OPFHs and PHs, except for BP, showed a significantly higher risk of headache or shoulder stiffness (odds ratio = 1.713; 95% confidence interval, 1.160–2.532; p = 0.007) than the non-BP group (Table 4). However, as CH and FD did not have significant differences in all items between TMD patients with and without CH or FD, OPFHs and PHs did not affect TMD symptoms (Table 4).

4. Discussion

Numerous epidemiological surveys of TMD have been designed and reported previously [5,28,29,30,31]. In these studies, the prevalence of TMD was examined in general subjects or patient populations, and varying incidence rates were reported, ranging from 20% to 50% [29]. These studies also indicated that TMDs have a multifactorial etiology and that OPFHs (e.g., nocturnal bruxism and clenching), DC (teeth contact habit), anatomical factors, trauma or general hypermobility of the joints, psychosocial issues (e.g., anxiety and depressive syndrome), and cervical posture are potential risk factors [29,32,33]. However, considering the presence of confounding factors, these findings imply that participants with OPFHs are subject to TMD symptoms and signs. Thus, to avoid confounds in the study design, a propensity score matching analysis was adopted in this study. The estimated propensity score is commonly applied in clinical or epidemiological studies [34]. It allows for dealing with various selection biases in retrospective studies, such as the pseudo-randomization of data [35]. Thus, this analysis can organize confounds by indication [36]. This can be applied to the comparison of observed prognostic factors, such as the effect, cost, or treatment duration between different clinical treatment groups. The estimated propensity score involves the extraneous factor that each patient had and is suitable to match the resembling patients using a fixed caliper, which is the nearest neighbor matching method. When using the propensity score-matched analysis in this study, demographic factors, individual medical or dental history, and the presence of jobs and hobbies were unified to remove confounding factors. To our knowledge, this is the first study in which a matched case–control analysis was conducted to identify the causes of TMD.
The present study showed that SB affected pain or fatigue of the masticatory muscles, and DC affected jaw pain, pain or fatigue of the masticatory muscles [21], and headache or shoulder stiffness in matched patients with a medical history and various habits. However, in patients without OPFHs and PHs, SB and DC were not considered potential risk factors for TMD symptoms. Thus, although SB or DC alone did not affect TMD symptoms, these habits might produce a risk for TMD symptoms when combined with other habits. Previous studies reported that various oral parafunctional factors can affect TMD symptoms [22,37,38,39,40]. Our results showed that masticatory muscle pain, fatigue, headache, or shoulder stiffness might develop combined OPHFs and PHs, and these TMD symptoms are recognized as a part of myofascial pain or fatigue [5]. Although management of myofascial pain or fatigue is not sufficient to resolve pathophysiological mechanisms, excessive extension or contraction might stimulate nociceptive neurons in the skeletal muscle. Furthermore, nociceptors on the terminals of nociceptive neurons develop pain or fatigue [41]. By continuing excessive activation in the peripheral nervous system, pain sensitivity might increase, and peripheral or central nervous plasticity may develop [42].
The following considerations and limitations of the present cohort survey should be addressed. First, as this cohort survey was performed using a propensity score-matched analysis, the results obtained were generalizable to the paired data by the range of propensity scores [34]. Therefore, the propensity score-matched method can reduce or remove the biases in demographic factors or medical history but not the effect of other biases from unobserved factors, such as information on internal medication, academic history, work history/current job, and annual income may persist [43]. Our score-matched analysis should be organized using the high propensity score-matched analysis because of the lack of unobserved confounding factors. Second, although SB was regarded as an OPFH in the self-report questionnaire, previous reports provided detailed information about the patients [44], for example, whether the patient is self-aware about SB and how frequently SB occurs in a week. However, each item for OPFH or PH in this self-report questionnaire was not included in detail, and this questionnaire was not applied in a pilot study with a smaller population. Finally, the questionnaire used in this survey did not include questions about occlusal status and masticatory performance [12]. The occlusal condition is an important factor in diagnosing TMDs; therefore, further surveys and investigations involving occlusal conditions are needed to identify the specific causative factors in patients with TMD.

5. Conclusions

In conclusion, we performed a propensity score-matched analysis using a large cohort of TMD patients with OFPHs and/or PHs. According to the results of our matched case–control study, SB, DC, and BP affected the stomatognathic system in terms of pain or fatigue while SB and DC did not affect TMD symptoms in patients without OPFHs and PHs. This implies that these habits might produce a risk for TMD symptoms owing to the coexistence of other habits.

Supplementary Materials

The following supporting information can be downloaded at: https://www.mdpi.com/article/10.3390/jcm11216396/s1, Table S1. Demographic and clinical characteristics of TMD patients with and without DC; Table S2. Demographic and clinical characteristics of TMD patients with and without DC if other OPFHs and PHs were absent; Table S3. Demographic and clinical characteristics of TMD patients with and without CH; Table S4. Demographic and clinical characteristics of TMD patients with and without CH if other OPFHs and PHs were absent; Table S5 Demographic and clinical characteristics of TMD patients with and without FD; Table S6. Demographic and clinical characteristics of TMD patients with and without FD if other OPFHs and PHs were absent; Table S7. Demographic and Clinical Characteristics of TMJ Patients with and without BP; Table S8. Demographic and clinical characteristics of TMD patients with and without BP if other OPFHs and PHs were absent.

Author Contributions

S.A., F.K., Y.M., T.M., T.O. and E.T. conceived and designed the research. S.A., Y.M., and E.T. acquired data. S.A., F.K., T.M., T.O. and E.T. analyzed data. S.A., Y.M., T.O. and E.T. wrote the manuscript. All authors gave their final approval and agreed to be accountable for all aspects of this work. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Grants-in-Aid 19K11323 (S.A.) for Science Research from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.

Institutional Review Board Statement

This study was approved by the Ethics Committee of Tokushima University Hospital (No. 2279-4).

Informed Consent Statement

Informed consent was obtained from all subjects involved in the study.

Acknowledgments

The authors thank Fumihiro Matsumoto, Yoshitaka Suzuki, Emi Takegawa, Hinayo Umeda, Daisuke Ikutame, Mariko Tanaka, Shigeki Hanawa, and Sooha Kim for their clinical assistance in this study.

Conflicts of Interest

The authors declare no conflict of interest.

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Jcm 11 06396 g001 550
Figure 1. Demographic data of TMD patients for age.
Figure 1. Demographic data of TMD patients for age.
Jcm 11 06396 g001
Table
Table 1. Questions for patients with TMD at the initial visit.
Table 1. Questions for patients with TMD at the initial visit.
TMJ Symptoms
 1. Do you have pain in the jaw joint?
 2. Do you have masticatory muscular pain or fatigue?
 3. Is it hard for you to open your mouth?
 4. Do you have clicking or popping sound in either or both jaws?
 5. Do you ever have frequent headaches or neck and/or shoulder pain?
 6. Do you ever have difficulty closing after opening wide? (joint luxation)
 7. How do you experience maximum pain related to this symptom? (Could you check the bars?)
 8. How do you have a daily hindrance related to this symptom? (Could you check the bars?)
Medical history or characteristics
 9. Have you ever had a previous medical history of TMD?
  If you answered “Yes”, was previous medical history same or different side for presence of TMD symptom?
 10. Have you ever had a previous TMD treatment?
 11. Have you ever had systemic bone or joint problems, such as rheumatic arthritis, gout, osteoporosis, or osteoarthritis?
 12. Have you ever injured your head, neck, jaw, or spine?
 13. Have you ever had orthodontic treatment?
 14. Which side do you usually or exclusively use during chewing, “Right side”, “Left side”, or “Both sides”?
 15. Do you consider yourself a nervous person?
 16. Do you frequently follow long-term desk work, long-time driving, hobbies, or sports?
Oral parafunctional or postural habits
 17. Do you grind your teeth during your sleep? (sleep bruxism)
 18. Do you clench or grind your teeth during the day? (awake bruxism or tooth contact habits)
 19. Do you rest your chin on your hand?
 20. Do you sleep lying face down?
 21. Do you have bad posture such as a hunch?
Table
Table 2. Demographic and clinical characteristics of TMD patients with and without SB. (1) Before propensity score matching. (2) After propensity score matching.
Table 2. Demographic and clinical characteristics of TMD patients with and without SB. (1) Before propensity score matching. (2) After propensity score matching.
(1) Before Propensity Score Matching
SB
Yes (=Presence)No (=Absence)p–Value
Age (years) 43.6 (28–57.8)
(N = 484)		53.4 (29.9–67.9)
(N = 1804)		<0.001
Gender Female352 (21.3%)1301 (78.7%)0.995
(N = 2292)Male136 (21.3%)503 (78.7%)
Medical history of TMJ
(N = 2211)		Yes and Same121 (24%)383 (76%)<0.001
Yes and Difference146 (25.7%)421 (74.3%)
No205 (18%)935 (82%)
TMD treatmentYes128 (24.1%)403 (75.9%)0.079
(N = 2269)No357 (20.5%)1381 (79.5%)
Systemic historyYes95 (19%)405 (81%)0.153
(N = 2276)No390 (22%)1386 (78%)
Head and neck injuryYes89 (23.8%)285 (76.2%)0.205
(N = 2277)No397 (20.9%)1506 (79.1%)
Orthodontic treatmentYes70 (29.4%)168 (70.6%)0.001
(N = 2285)No418 (20.4%)1629 (79.6%)
Chewing side
(N = 2257)		Both side174 (20.1%)691 (79.9%)0.147
Right side164 (20.3%)642 (79.7%)
Left side141 (24.1%)445 (75.9%)
Nervous personYes336 (23.3%)1106 (76.7%)0.003
(N = 2262)No147 (17.9%)673 (82.1%)
Desk work and recreationYes294 (23.9%)936 (76.1%)0.002
(N = 2217)No183 (18.5%)804 (81.5%)
SBYes278 (34.4%)530 (65.6%)<0.001
(N = 2292)No210 (14.2%)1274 (85.8%)
CHYes141 (25.8%)405 (74.2%)0.003
(N = 2292)No347 (19.9%)1399 (80.1%)
FDYes93 (25.1%)277 (74.9%)0.049
(N = 2292)No395 (20.6%)1527 (79.4%)
BPYes243 (24.4%)752 (75.6%)0.001
(N = 2292)No245 (18.9%)1052 (81.1%)
(2) After Propensity Score Matching
SB
Yes (=Presence)No (=Absence)p–Value
Age (years)43.4 (27.4–58.4)
(N = 452)		43.6 (24.1–59.8)
(N = 452)		0.873
Gender Female330 (50.5%)323 (49.5%)0.603
(N = 904)Male122 (48.6%)129 (51.4%)
Medical history of TMJ
(N = 904)		Yes and Same116 (48.9%)121 (51.1%)0.920
Yes and Difference137 (50.7%)133 (49.3%)
No199 (50.1%)198 (49.9%)
TMD treatmentYes121 (48%)131 (52%)0.458
(N = 904)No331 (50.8%)321 (49.2%)
Systemic historyYes91 (50%)91 (50%)1.000
(N = 904)No361 (50%)361 (50%)
Head and neck injuryYes88 (49.7%)89 (50.3%)0.933
(N = 904)No364 (50.1%)363 (49.9%)
Orthodontic treatmentYes63 (52.1%)58 (47.9%)0.625
(N = 904)No389 (49.7%)394 (50.3%)
Chewing side
(N = 940)		Both side164 (47.4%)182 (52.6%)0.465
Right side150 (51.4%)142 (48.6%)
Left side138 (51.9%)128 (48.1%)
Nervous personYes311 (49.8%)313 (50.2%)0.886
(N = 904)No141 (50.4%)139 (49.6%)
Desk work and recreationYes278 (50.5%)273 (49.5%)0.733
(N = 904)No174 (49.3%)179 (50.7%)
DCYes255 (49.7%)258 (50.3%)0.840
(N = 904)No197 (50.4%)194 (49.6%)
CHYes132 (49.8%)133 (50.2%)0.942
(N = 904)No320 (50.1%)319 (49.9%)
FDYes86 (47.8%)94 (52.2%)0.505
(N = 904)No366 (50.6%)358 (49.4%)
BPYes221 (49.1%)229 (50.9%)0.595
(N = 904)No231 (50.9%)223 (49.1%)
Table
Table 3. Demographic and clinical characteristics of TMD patients with and without SB, in case the other OPFHs and PHs are absent.
Table 3. Demographic and clinical characteristics of TMD patients with and without SB, in case the other OPFHs and PHs are absent.
(1) Before Propensity Score Matching
SB
Yes (=Presence)No (=Absence)p–Value
Age (years)54.8 (39.5–67.7)
(N = 89)		63.6 (47.1–73.2)
(N = 586)		0.001
Gender Female59 (12.7%)404 (87.3%)0.616
(N = 675)Male30 (14.2%)182 (85.8%)
Medical history of TMJ
(N = 647)		Yes and Same15 (12.5%)105 (87.5%)0.278
Yes and Difference23 (17.3%)110 (82.7%)
No47 (11.9%)347 (88.1%)
TMD treatmentYes21 (14.8%)121 (85.2%)0.527
(N = 667)No67 (12.8%)458 (87.2%)
Systemic historyYes22 (11.6%)167 (88.4%)0.479
(N = 671)No66 (13.7%)416 (86.3%)
Head and neck injuryYes14 (14.7%)81 (85.3%)0.643
(N = 672)No75 (13%)502 (87%)
Orthodontic treatmentYes7 (17.1%)34 (82.9%)0.453
(N = 673)No82 (13%)550 (87%)
Chewing side
(N = 669)		Both side33 (11.5%)255 (88.5%)0.021
Right side24 (11%)195 (89%)
Left side32 (19.8%)130 (80.2%)
Nervous personYes53 (15.3%)294 (84.7%)0.131
(N = 666)No36 (11.3%)283 (88.7%)
Desk work and recreationYes45 (15.6%)243 (84.4%)0.105
(N = 659)No42 (11.3%)329 (88.7%)
(2) After Propensity Score Matching
SB
Yes (=Presence)No (=Absence)p–Value
Age (years)55.9 (39.6–67.7)
(N = 83)		52.9 (28.4–72.9)
(N = 83)		0.626
Gender Female55 (50.9%)53 (49.1%)0.745
(N = 166)Male28 (48.3%)30 (51.7%)
Medical history of TMJ
(N = 166)		Yes and Same15 (51.7%)14 (48.3%)0.978
Yes and Difference22 (50%)22 (50%)
No46 (49.5%)47 (50.5%)
TMD treatmentYes19 (51.4%)18 (48.6%)0.852
(N = 166)No64 (49.6%)65 (50.4%)
Systemic historyYes21 (48.8%)22 (51.2%)0.859
(N = 166)No62 (50.4%)61 (49.6%)
Head and neck injuryYes14 (42.4%)19 (57.6%)0.331
(N = 166)No69 (51.9%)64 (48.1%)
Orthodontic treatmentYes6 (40%)9 (60%)0.417
(N = 166)No77 (51%)74 (49%)
Chewing side
(N = 166)		Both side33 (47.8%)36 (52.2%)0.594
Right side22 (46.8%)25 (53.2%)
Left side28 (56%)22 (44%)
Nervous personYes48 (50%)48 (50%)1.000
(N = 166)No35 (50%)35 (50%)
Desk work and recreationYes42 (51.9%)39 (48.1%)0.641
(N = 166)No41 (48.2%)44 (51.8%)
Table
Table 4. Logistic regression analysis of TMD symptoms with the presence of targeted habit with reference to the absence of SB in the propensity-matched group. (1) Regardless of the presence or absence of other OPFHs and PHs. (2) In cases where other OPFHs and PHs are absent, except for the targeted habits.
Table 4. Logistic regression analysis of TMD symptoms with the presence of targeted habit with reference to the absence of SB in the propensity-matched group. (1) Regardless of the presence or absence of other OPFHs and PHs. (2) In cases where other OPFHs and PHs are absent, except for the targeted habits.
(1)HabitNOdds Ratio95% Confidence Intervalp–Value
Pain in jaw jointSB8411.0510.776–1.4250.746
DC12281.3721.063–1.7700.015
CH9350.9540.715–1.2720.749
FD6231.1860.836–1.6830.339
BP12690.8900.695–1.1390.354
Masticatory muscular pain/fatigueSB8291.5231.074–2.1590.018
DC12091.4771.100–1.9820.009
CH9081.1270.782–1.6230.521
FD6080.8240.535–1.2690.378
BP12401.3060.972–1.7540.076
Hard to open mouthSB8290.7810.594–1.0270.077
DC12141.0230.816–1.2820.847
CH9131.0450.804–1.3570.742
FD6101.2380.900–1.7030.189
BP12480.8800.704–1.1000.261
Clicking/popping in jawSB8520.8230.620–1.0920.176
DC12440.8770.696–1.1040.176
CH9380.9020.691–1.1780.448
FD6381.3570.978–1.8830.068
BP12911.1690.930–1.4690.180
Headache/shoulder stiffnessSB8241.2180.926–1.6020.159
DC12061.5091.203–1.894<0.001
CH9080.9480.730–1.2290.685
FD6061.1690.850–1.6100.337
BP12381.5991.278–2.002<0.001
Joint luxationSB8270.7480.400–1.4000.363
DC12060.7390.424–1.2880.285
CH9090.7520.425–1.3290.325
FD6061.3860.696–2.7610.352
BP12370.8700.520–1.4570.596
(1) Targeted Habit
HabitNYes (=Presence)No (=Absence)p–Value
Maximum Pain (VAS)SB88840.00 (11.50–56.50)40.00 (12.00–61.00)0.548
DC129141.50 (18.00–60.00)36.00 (9.00–55.00)0.003
CH97635.00 (13.00–55.00)42.00 (13.25–60.00)0.151
FD67135.00 (12.00–56.00)35.00 (10.00–55.00)0.769
BP134640.00 (14.00–56.00)40.00 (14.00–58.00)0.616
Daily Hindrance (VAS)SB87747.00 (20.00–62.00)45.00 (20.00–60.00)0.828
DC128249.00 (22.00–64.00)45.50 (19.00–56.00)0.010
CH96940.00 (18.00–55.25)47.00 (20.00–60.00)0.062
FD67042.00 (19.00–56.00)40.00 (18.50–58.00)0.887
BP133649.00 (21.25–61.75)45.00 (20.00–57.00)0.078
(2)HabitNOdds Ratio95% Confidence Intervalp–Value
Pain in jaw jointSB1490.8440.375–1.9010.683
DC3551.2810.792–2.0730.312
CH1361.0400.479–2.2600.921
FD991.5310.661–3.5470.319
BP4301.0170.672–1.5400.935
Masticatory muscular pain/fatigueSB1421.8100.727–4.5040.198
DC3421.4660.850–2.5260.167
CH1310.3950.097–1.5980.180
FD961.9550.459–8.3180.358
BP4161.6180.913–2.8660.097
Hard to open mouthSB1450.6980.363–1.3420.281
DC3440.9010.589–1.3790.632
CH1331.0920.551–2.1650.801
FD961.6350.711–3.7580.246
BP4200.9750.664–1.4320.897
Clicking/popping in jawSB1520.8200.429–1.5680.549
DC3560.7320.479–1.1190.149
CH1400.5300.270–1.0410.064
FD1060.6590.295–1.4730.308
BP4441.0520.714–1.5510.798
Headache/shoulder stiffnessSB1421.4740.758–2.8670.252
DC3421.0600.692–1.6240.790
CH1310.9140.450–1.8560.804
FD961.4970.650–3.4460.342
BP4181.7131.160–2.5320.007
Joint luxationSB1430.2500.027–2.2940.187
DC3420.3470.090–1.3300.107
CH1310.7740.198–3.0220.712
FD970.2850.054–1.4880.117
BP4160.5320.218–1.2970.159
(2) Targeted Habit
HabitNYes (=Presence)No (=Absence)p–Value
Maximum Pain (VAS)SB16229.50 (8.00–53.50)34.00 (5.00–54.75)0.916
DC37642.00 (17.50–61.00)35.00 (10.00–55.00)0.068
CH14430.00 (12.50–51.50)35.00 (3.00–53.00)0.997
FD10535.00 (12.25–58.00)23.00 (0.00–53.00)0.110
BP46146.00 (13.50–60.75)35.00 (5.00–58.50)0.073
Daily Hindrance (VAS)SB15845.00 (19.00–52.00)48.50 (19.75–58.00)0.382
DC37245.50 (20.00–63.00)46.00 (15.50–60.00)0.313
CH14537.00 (12.50–50.00)39.00 (14.00–51.50)0.698
FD10745.00 (25.00–53.00)39.00 (14.25–53.75)0.352
BP45950.00 (23.50–59.50)38.50 (13.00–56.25)0.007
SB: sleep bruxism, DC: diurnal grinding or clenching, CH: chin on hand, FD: face down, BP: bad posture. In bold: Variables with significant difference.
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Abe, S.; Kawano, F.; Matsuka, Y.; Masuda, T.; Okawa, T.; Tanaka, E. Relationship between Oral Parafunctional and Postural Habits and the Symptoms of Temporomandibular Disorders: A Survey-Based Cross-Sectional Cohort Study Using Propensity Score Matching Analysis. J. Clin. Med. 2022, 11, 6396. https://doi.org/10.3390/jcm11216396

AMA Style

Abe S, Kawano F, Matsuka Y, Masuda T, Okawa T, Tanaka E. Relationship between Oral Parafunctional and Postural Habits and the Symptoms of Temporomandibular Disorders: A Survey-Based Cross-Sectional Cohort Study Using Propensity Score Matching Analysis. Journal of Clinical Medicine. 2022; 11(21):6396. https://doi.org/10.3390/jcm11216396

Chicago/Turabian Style

Abe, Susumu, Fumiaki Kawano, Yoshizo Matsuka, Taeko Masuda, Toshinori Okawa, and Eiji Tanaka. 2022. "Relationship between Oral Parafunctional and Postural Habits and the Symptoms of Temporomandibular Disorders: A Survey-Based Cross-Sectional Cohort Study Using Propensity Score Matching Analysis" Journal of Clinical Medicine 11, no. 21: 6396. https://doi.org/10.3390/jcm11216396

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