TMJ
Prevalence of temporomandibular joint disorder among North Saudi University students Abdalwhab M. A. Zwiri1, Mahmoud K. Al-Omiri2,3 1
Department of Oral Medicine and Periodontics, Faculty of Dentistry, Aljouf University, Sakaka, KSA, Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman, Jordan, 3The City of London School of Dentistry, London, UK
2
Objective: The aim of the current investigation was to study the prevalence of temporomandibular disorder (TMD) among university students of North Saudi Arabia. Methods: A specifically constructed questionnaire was distributed to 489 university students to investigate the prevalence of temporomandibular joint (TMJ) findings among them. The study sample consisted of 346 males and 143 females (age range was 18–25 years). The data were analyzed, and probability values were set at Pj0.05. Results: A total of 49.7% of participants had at least one sign or symptom of TMD. Clicking was the most reported finding. Pain in or about the ears/cheeks was the second most common finding. In all, 24.3% of the participants reported one TMJ finding; meanwhile, 0.4% reported the presence of five concurrent TMJ signs and symptoms. Females reported more TMJ signs and symptoms than males (Pv0.05). Science and health students reported more TMD findings than humanitarian college students (Pv0.05). Discussion: University students in north Saudi Arabia reported high prevalence of TMD. Also, students from science and health colleges reported higher prevalence of TMD findings than humanitarian college students. Clicking and pain are the most prevalent findings of TMD among university students. The results of this investigation highlight the need for additional research to shed more light on the risk factors and findings related to TMD. This will facilitate drawing adequate guidelines for prevention and management of TMD. Keywords: TMD, Temporomandibular dysfunction, Temporomandibular joint, Prevalence, Saudi, University students
Introduction In recent years, temporomandibular joint disorder (TMD) has signified a universal health dilemma.1–16 According to the American Dental Association, TMD is defined as a group of orofacial disorders characterized by pain in the preauricular area, temporomandibular joint (TMJ), or muscles of mastication, limitations, and deviations in mandibular range of motion, and TMJ sounds during jaw function.4 In 1998, Luther5 used the term TMD to signify the variety of symptoms, signs, and combinations thereof that have been assigned to the TMJ and its related structures. Thus, it becomes apparent that clinicians cannot agree upon a precise definition for TMD.
Correspondence to: Mahmoud K. Al-Omiri, Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman 11942, Jordan. Email: [email protected] ß W. S. Maney & Son Ltd 2015 DOI 10.1179/2151090315Y.0000000007
Temporomandibular disorder is a heterogeneous group of pathologies affecting the TMJ, the jaw muscles, or both. Therefore, the term TMD could be regarded as an umbrella for a number of clinical findings that affect TMJ and masticatory muscles.6,7 It is not only difficult to diagnose TMJ problems in the beginning but often their proper treatment is also controversial.6,8 There is no such distinction concerning other joints in the body. Thorough knowledge is necessary for the established diagnosis to result in correct treatment.6,8 In addition, TMD findings might differ between individuals and within the same individual at various times, which further complicates TMD diagnosis and renders it more difficult.9 Temporomandibular disorder is considered to be the most common orofacial pain condition of non-dental origin. Nevertheless, the assessment of TMD prevalence is a complex issue, due to the frequent concurrent
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presence of other symptoms, such as earache, headache, neuralgia, and tooth pain, which may be related to the TMD or be present as ancillary findings to be assessed in the differential diagnosis process.8 The reported prevalence of TMD among different general populations is high. Cross-sectional prevalence studies have reported that approximately 40–87% of the participants had one or more TMD findings, and approximately 33% had at least one sign or symptom.10–16 Pain is the most important symptom in temporomandibular joint dysfunction (TMD) for both the patient and the clinician, and is the main reason why patients with TMJ disease seek medical help.17 According to some researchers, it is commonly accepted that TMD is of multifactorial origin and is best thought of as the result of a combination of occlusal, neurophysiologic, and psychological factors.18 Low self esteem was associated with more prevalent TMD findings.19 Psychological and emotional features are obviously linked with the prevalence of TMD findings.20,21 Based on psychometric differences, it is currently justified to subcategorize patients with myofascial pain dysfunction into a myogenic pain group and a TMJ-related pain group.22 Temporomandibular dysfunction might influence any individual with different signs and symptoms irrespective of gender12 or age, including children.23 Proffit and Fields24 claimed that there was female preponderance in TMJ discomfort, and that TMJ discomfort occurred more in persons with a history of jaw trauma. Some researchers claimed that university students (18–25 years old) had higher prevalence of TMD symptoms than older subjects25 and populations of rural areas.26 Symptoms of TMD were remarkably prevalent among samples representative of the student community in Jordan and Brazil.7,27 Not enough data are available regarding prevalence of TMJ symptoms among university students in Saudi. Therefore, this study was conducted to investigate prevalence of TMD among university students from north Saudi Arabia, using the guidelines recommended by the American Dental Association, and to compare the prevalence of TMD among students from different faculties, in an attempt to recognize the risk groups for TMD development. The Null hypothesis was that TMD is not prevalent among university students, and that students from different faculties have similar TMD prevalence.
The study was approved by Deanship of Research, Aljouf University, Sakaka, Saudi Arabia. Each participant was provided with a full explanation of the study and how to complete the required questionnaire. Participants’ written informed consent was obtained before being recruited into the study. To be included in the study, participants had to be university students, have no medical or mental issues that affected their ability to comprehend or complete the questionnaire, have no dental pain, have no bony lesions in the jaws, and have no problems related to third molar eruption. All participants were examined under a dental unit light using a dental mirror, and had an orthopantographic radiograph (OPG), in order to rule out any bony lesion, any problem related to third molar eruption, or any dental related disease that could cause pain or findings confused with TMD. Participants with problems related to dental disease, bony lesions, or third molar eruption were excluded from the study. In total, 489 students (346 males and 143 females) were recruited into the study. Participants’ age range was from 18 to 25 years old (mean520.8 years old, SD51.7 years). First-year students formed 33.1% of the sample (162 students), while 30.3% (148 students) of the sample were second-year students, 22.1% (108 students) were third-year students, 13.5% (66 students) were fourth-year students, and 1% (5 students) were fifth-year students. Moreover, 304 (62.2%) of the participants were studying at humanitarian colleges, 95 (19.4%) were health college students, and 90 (18.4%) were science college students. A questionnaire was constructed and dispensed randomly to participants (Appendix 1). There was no time limit for completion of the questionnaire, so there was no reason for the subject to give induced answers. The completed questionnaire contained items regarding the different symptoms of TMD and the possible risk factors. Statistical analysis was carried out using SPSS software (Version 19.0, SPSS Inc., Chicago, IL, USA). Pearson correlation test was used to find out the relationships between the TMD findings and independent factors. To identify potential confounding variables for the TMD findings, a stepwise multivariate logistic regression was utilized. Probability values were set at Pj0.05.
Results Materials and Methods The study sample was derived from officially registered students studying at Aljouf University. 2
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Table 1 presents the prevalence of different TMD findings among the study sample. Clicking was the most prevalent TMD finding among the study VOL .
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Table 1 The prevalence of various findings of TMD in the study population according to gender and field of study (n5489). Number of respondents Health and Science
Humanitarian
TMD findings
Male
Female
Male
Female
Total prevalence (%)
Clicking Pain on or about ear Difficulty with chewing Limitation in mouth opening Pain on chewing
20 19 11 12 6
21 25 15 5 12
77 61 44 32 17
25 13 10 14 3
29.2 24 16.4 12.9 7.8
TMD: temporomandibular disorder.
population. Pain in or about the ears or cheeks was less prevalent than clicking, meanwhile pain during chewing was the least prevalent finding (Table 1). Nearly half of the participants (246 students) reported no TMD findings, while 49.7% (243) of them had one or more finding. Among those who had TMD findings, 24.3% (119 students) had one symptom, while 0.4% (2 students) had five coexisting TMD findings (Table 2). The five symptoms of TMD were found to be significantly associated and occurred together (Pv0.05). Females had more TMD findings than males (r50.509, P50.000). Also, there were significant correlations between TMD findings and field of study (r50.197, P50.000); TMD findings were significantly more prevalent among students from science and health colleges, while the least prevalent findings were reported by students from humanitarian colleges. Temporomandibular disorder findings were more prevalent among students who experienced trauma to the maxillofacial area (r50.166, P50.000), or who were unsatisfied with their appearance or study achievement (r50.143, P50.002). Moreover, TMD symptoms were more prevalent among participants who suffer clenching (r50.122, P50.007) or limited mouth opening (r50.126, P50.005). A stepwise multivariate logistic regression analysis showed that pain, clicking, limited mouth opening, and bruxism had strong associations with the presence of TMD (Pv0.05) (Table 3). The multicollinearity within the regression model (the correlation between the
Table 2 The prevalence of concurrent TMD symptoms in the study population Number of concurrent symptoms 5 4 3 2 1 TMD: temporomandibular disorder.
Number of respondents (%) 2 (0.4) 17 (3.5) 35 (7.2) 70 (14.3) 119 (24.3)
independent variables within the regression model) was tested, and revealed that the tolerance value was larger than 0.1 and the variance inflation factor (VIF) was less than 10 for all variables (Table 3). No significant correlation between the independent variables was found, and thus the variables do not depend on each other and do not measure the same concept. This ensures the accuracy of the calculated model, where pain, clicking, limited mouth opening, and bruxism had strong associations with the presence of TMD.
Discussion This study found that university students in north Saudi Arabia reported a high prevalence of TMD. Also, students from science and health colleges reported a higher prevalence of TMD findings than humanitarian college students. Therefore, the null hypothesis was rejected. This study showed that TMD findings were common among the study sample of North Saudi students at Aljouf University. This is in harmony with findings of previous studies on Brazilian27 and Jordanian7 university students. Clicking was the most common TMD finding in this investigation, which agrees with the findings of previous studies.16,28 Also, periauricular pain was found to be the second most common symptom among the participants, and this contrasts with some studies7 that reported periauricular pain as the most common symptom of TMD. In the current study, female participants reported a higher prevalence of TMD findings than males; a finding that is in agreement with the results of earlier investigations.3,27 Also, in this study, science and health college students reported more TMD findings. The reasons behind this could be the larger study load that associates their courses, the higher competition required for admission to science and health colleges in comparison to humanitarian colleges, and the
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Table 3 Stepwise logistic regression for findings of TMD Collinearity statistics TMD findings
Standardized coefficients beta
T
P-value
Clicking on yawning Clicking after awaking Pain after awaking Pain during eating Pain under stress Pain during yawning Pain during speaking Difficulty in mouth opening Bruxism
0.071 0.052 0.315 0.320 0.237 0.407 0.109 {0.046 0.081
2.730 2.027 13.536 13.662 9.101 15.694 4.661 {1.986 3.496
0.007 0.043 0.000 0.000 0.000 0.000 0.000 0.048 0.001
Tolerance 0.732 0.766 0.918 0.904 0.732 0.738 0.913 0.921 0.932
VIF 1.367 1.306 1.090 1.106 1.366 1.355 1.095 1.086 1.073
Predictors: TMD findings, Dependant variable5TMD incidence, R square50.774, Standard error of the estimate50.20623. VIF: variance inflation factor; TMD: temporomandibular disorder.
possibility of higher levels of stress and anxiety among science and health students. In the present study, TMD findings were significantly related to emotional and psychological features. This result concurs with the findings of earlier investigations.29,30 Trauma to the maxillofacial region was significantly related to TMD findings among the study sample; this concurs with the results of previous studies that associated trauma with TMD findings.31 The results of this investigation highlight the need for additional research to shed more light on the risk factors and findings related to TMD. This will facilitate drawing adequate guidelines for prevention and management of TMD. Also, the findings of this study support the idea of conducting regular examinations for university students in order to allow early diagnosis and prompt management of TMD. Study limitations include the use of questionnaires to investigate symptoms of TMD, which is a subjective method of research. However, every attempt was made to adequately explain the questionnaire and the study to the participants, and participants were given no time limits to complete the questionnaires. Additionally, the number of selected students in each year was not similar, due to variations in the number of students in each year and variations in acceptance to participate in the study between students from different years of study. This could affect the obtained results. However, since the students were of a similar age group, the effect of this point on the results would not undermine the results of this study, and this was the reason why the relationship exists between prevalence of TMD findings and year of study. This could be an area for further research. No studies were found in the literature on TMD findings among individuals who are non-university students and of similar age group to university 4
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students. This could be because it is difficult to find subjects who are in the same age group, but not university or college students. Therefore, it was not possible to compare the results of this investigation to non-university students of a similar age group. However, previous studies on university students did not use controls of a similar age and did not study non-university students who are of the same age of university students. This could be an area for future research. Further studies are also required on larger samples and different populations to identify the effects of racial and cultural backgrounds on the development of TMD.
Conclusions Within the limitations of this investigation, it was concluded that university students in north Saudi Arabia reported a high prevalence of TMD. Also, students from science and health colleges reported a higher prevalence of TMD findings than humanitarian college students. Clicking and pain were the most prevalent findings of TMD among the study sample.
Acknowledgements The authors would like to thank Aljouf University for supporting this research (Reference number 34/171).
Disclaimer Statements Contributors Prof Mahmoud Al-Omiri: conceived and designed the study, obtained funding and ethical approval, collected the data, analyzed and interpreted the data, and wrote and revised the article. Dr Abdalwhab M. A. Zwiri: conceived and designed the study, obtained funding and ethical approval, collected the data, interpreted the data, and wrote and revised the article. Funding Aljouf University, Sakaka, Saudi Arabia. VOL .
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Conflicts of interest The authors have no conflict of interest. Ethics approval Ethical approval was obtained by Deanship of Research, Aljouf University, Sakaka, Saudi Arabia. Reference number 34/171.
Appendix 1: The Questionnaire Used in this Study (1) Do you usually hear a click at your temporomandibular joint? Yes % No % (2) When do you usually hear the click? (3) Is your click painful? Yes % No % (4) Do you know anyone with TMD? Yes % No % (5) Have you ever sought treatment for pain or click in your joint? Yes % No % (6) Do you have chewing difficulty? Yes % No % (7) Do you usually feel pain at your temporomandibular joint? Yes % No % (1) % After awaking Yes % No % (2) % During eating Yes % No % (3) % When under stress Yes % No % (4) % During yawning Yes % No % (5) % During speaking Yes % No % (6) % All the time Yes % No % (8) Do you usually complain of headache? Yes % No % (9) Do you usually complain of pain in the neck? Yes % No % (10) Do you usually complain of pain in the shoulders? Yes % No % (11) Have you ever had difficulty in opening your mouth? Yes % No % (12) Do you usually clench your teeth during day time? Yes % No % (13) Do people hear your bruxism sound at night? Yes % No % (14) Do you usually use any of the following?
Chewing gum Yes % No % Nuts Yes % No % Long phone call Yes % No % The habit of biting on a hard objects (e.g. pencil) Yes % No % (15) Have you ever had any of the following? Trauma to the chin or face Yes % No % Subjected to a lengthy extraction of posterior teeth or Lengthy dental appointment Yes % No % Missing posterior teeth Yes % No % Orthodontic treatment Yes % No % (16) Are you satisfied with your: Accomplishment in the university Yes % No % Appearance Yes % No % Life style Yes % No % (17) Do you have any sleeping disorder (not getting enough sleep) Yes % No %
Prevalence of temporomandibular joint disorder
(18) Do you complain of any of the following diseases?
Rheumatoid arthritis Yes % No % Lupus erythematousus Yes % No % Psoriasis Yes % No % Hypermobility of joints disorder Yes % No % Gout Yes % No % Reflux (heartburn) Yes % No % Low back pain Yes % No %
References 1 Sari S, Sonmez H. Investigation of the relationship between oral parafunctions and temporomandibular joint dysfunction in Turkish children with mixed and permanent dentition. J Oral Rehabil. 2002;29:108–12. 2 James BA. Costen syndrome of ear and sinus symptoms dependent upon disturbed function of the temporomandibular joint. Ann Otol Rhinol Laryngol. 1934;43:1–15. 3 Roda RP, Jose´ V, Baga´n JV, Ferna´ndez JMD, Baza´n SH, Soriano YJ. Review of temporomandibular joint pathology. Part I: classification, epidemiology and risk factors. Med Oral Patol Oral Cir Bucal. 2007;12:E292–8. 4 Laskin D, Greenfield W, Gale E. The president’s conference on the examination, diagnosis and management of temporomandibular disorders. Chicago: American Dental Association; 1983. 5 Luther F. Orthodontics and the temporomandibular joint: where are we now? Part I. Orthodontic treatment and temporomandibular disorders. Angle Orthod. 1998;68:295–304. 6 McNeill C. Management of temporomandibular disorders: concepts and controversies. J Prosthet Dent. 1997;77:510–22. 7 Ryalat S, Baqain ZH, Amin W, Sawair F, Samara O, Badran DH. Prevalence of temporomandibular joint disorders among students of the University of Jordan. J Clin Med Res. 2009;1:158–64. 8 Leresche L. Epidemiology of temporomandibular disorders: implications for the investigation of etiologic factors. Critical Rev Oral Biol Med. 1997;8:291–305. 9 Cooper BC, Kleinberg I. Examination of a large patient population for the presence of symptoms and signs of temporomandibular disorders. J Craniomandib Pract. 2007;25:114–26. 10 Solberg WK. Temporomandibular disorders: background and the clinical problem. Br Dent J. 1986;160:157–67. 11 Schiffman EL, Fricton JR, Haley DP, Shapiro BL. The prevalence and treatment needs of subjects with temporomandibular disorders. J Am Dent Assoc. 1990;120:295–303. 12 Nassif NJ, Hilsen KL. Screening for temporomandibular disorders: history and clinical examination. American Dental Association. J Prosthodont. 1992;1:42–6. 13 McNeill C, editor. Temporomandibular disorders. Guidelines for classification, assessment and management. 2nd edn. London: The Academy of Orofacial Pain, Quintessence; 1993. 14 Carlsson GE, Magnusson T, editors. Management of temporomandibular disorders in the general dental practice. London: Quintessence; 1999; p. 13–17. 15 Chuang SY. Incidence of temporomandibular disorders (TMDs) in senior dental students in Taiwan. J Oral Rehabil. 2002;29:1206–11. 16 Okeson JP, editor. Management of temporomandibular disorders and occlusion. 3rd edn. St. Louis: Mosby; 2003; p. 413–35. 17 Roda RP, Ferna´ndez JMD, Baza´n SH, Soriano YJ, Margaix M, Sarrio´n G. A review of temporomandibular joint disease (TMJD). Part II: clinical and radiological semiology morbidity processes. Med Oral Patol Oral Cir Bucal. 2008;13:E102–9. 18 Moss RA, Garret J, Chiodo JF. Temporomandibular joint dysfunction and myofacial pain dysfunction syndromes: parameters etiology and treatment. Psychol Bull. 1982;92:331–46. 19 Godoy F, Rosenblatt A, Godoy-Bezerra J. Temporomandibular disorders and associated factors in Brazilian teenagers: a cross-sectional study. Int J Prosthodont. 2007;20:599–604. 20 Gerke DC, Goss AN, Bassett DL. Psychological factors in temporomandibular joint dysfunction: life events. Aust Prosthodont J. 1990;4:29–34. 21 Manfredini D, Landi N, Bandettini Di Poggio A, Dell’Osso L, Bosco M. A critical review on the importance of psychological
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factors in temporomandibular disorders. Minerva Stomatol. 2003;52:321–30. Dahlstrom WG, Welsh GS, Dahlstrom LE. An MMPI handbook, Vol II, clinical interpretation. Minneapolis: University of Minnesota Press; 1972. Nilner M, Lassing SA. Prevalence of functional disturbances and diseases of the stomatognathic system in 7-14 year olds. Swed Dent J. 1981;5:173–87. In: Proffit WR, Fields HW, editors. Contemporary orthodontics. 3rd edn. St. Louis: Mosby; 2000; p. 201–8. Osterberg T, Carlsson GE, Wedel A, Johansson U. A cross-sectional and longitudinal study of craniomandibular dysfunction in an elderly population. J Craniomandib Disord. 1992;6:237–45. Goddard G, Karibe H. TMD prevalence in rural and urban Native American populations. J Craniomandib Pract. 2002;20:125–8.
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27 Pedroni CR, De Oliveira AS, Guaratini MI. Prevalence study of signs and symptoms of temporomandibular disorders in university students. J Oral Rehabil. 2003;30:283–9. 28 Shiau YY, Chang C. An epidemiological study of temporomandibular disorders in university students of Taiwan. Community Dent Oral Epidemiol. 1992;20:43–7. 29 Filho J, Manzi FR, de Freitas DQ, Boscolo FN, de Almeida SM. Evaluation of temporomandibular joint in stress free patients. Dentomaxillofac Radiol. 2007;36:336–40. 30 Speculand B, Hughes AO, Goss AN. Role of recent stressful life events experience in the onset of TMJ dysfunction pain. Community Dent Oral Epidemiol. 1984;12:197–202. 31 Klobas L, Tegelberg A, Axelsson S. Symptoms and signs of temporomandibular disorders in individuals with chronic whiplash-associated disorders. Swed Dent J. 2004;28:29–36.
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Prevalence of temporomandibular joint disorder among North Saudi University students Abdalwhab M. A. Zwiri1, Mahmoud K. Al-Omiri2,3 1
Department of Oral Medicine and Periodontics, Faculty of Dentistry, Aljouf University, Sakaka, KSA, Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman, Jordan, 3The City of London School of Dentistry, London, UK
2
Objective: The aim of the current investigation was to study the prevalence of temporomandibular disorder (TMD) among university students of North Saudi Arabia. Methods: A specifically constructed questionnaire was distributed to 489 university students to investigate the prevalence of temporomandibular joint (TMJ) findings among them. The study sample consisted of 346 males and 143 females (age range was 18–25 years). The data were analyzed, and probability values were set at Pj0.05. Results: A total of 49.7% of participants had at least one sign or symptom of TMD. Clicking was the most reported finding. Pain in or about the ears/cheeks was the second most common finding. In all, 24.3% of the participants reported one TMJ finding; meanwhile, 0.4% reported the presence of five concurrent TMJ signs and symptoms. Females reported more TMJ signs and symptoms than males (Pv0.05). Science and health students reported more TMD findings than humanitarian college students (Pv0.05). Discussion: University students in north Saudi Arabia reported high prevalence of TMD. Also, students from science and health colleges reported higher prevalence of TMD findings than humanitarian college students. Clicking and pain are the most prevalent findings of TMD among university students. The results of this investigation highlight the need for additional research to shed more light on the risk factors and findings related to TMD. This will facilitate drawing adequate guidelines for prevention and management of TMD. Keywords: TMD, Temporomandibular dysfunction, Temporomandibular joint, Prevalence, Saudi, University students
Introduction In recent years, temporomandibular joint disorder (TMD) has signified a universal health dilemma.1–16 According to the American Dental Association, TMD is defined as a group of orofacial disorders characterized by pain in the preauricular area, temporomandibular joint (TMJ), or muscles of mastication, limitations, and deviations in mandibular range of motion, and TMJ sounds during jaw function.4 In 1998, Luther5 used the term TMD to signify the variety of symptoms, signs, and combinations thereof that have been assigned to the TMJ and its related structures. Thus, it becomes apparent that clinicians cannot agree upon a precise definition for TMD.
Correspondence to: Mahmoud K. Al-Omiri, Department of Prosthodontics, Faculty of Dentistry, University of Jordan, Amman 11942, Jordan. Email: [email protected] ß W. S. Maney & Son Ltd 2015 DOI 10.1179/2151090315Y.0000000007
Temporomandibular disorder is a heterogeneous group of pathologies affecting the TMJ, the jaw muscles, or both. Therefore, the term TMD could be regarded as an umbrella for a number of clinical findings that affect TMJ and masticatory muscles.6,7 It is not only difficult to diagnose TMJ problems in the beginning but often their proper treatment is also controversial.6,8 There is no such distinction concerning other joints in the body. Thorough knowledge is necessary for the established diagnosis to result in correct treatment.6,8 In addition, TMD findings might differ between individuals and within the same individual at various times, which further complicates TMD diagnosis and renders it more difficult.9 Temporomandibular disorder is considered to be the most common orofacial pain condition of non-dental origin. Nevertheless, the assessment of TMD prevalence is a complex issue, due to the frequent concurrent
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presence of other symptoms, such as earache, headache, neuralgia, and tooth pain, which may be related to the TMD or be present as ancillary findings to be assessed in the differential diagnosis process.8 The reported prevalence of TMD among different general populations is high. Cross-sectional prevalence studies have reported that approximately 40–87% of the participants had one or more TMD findings, and approximately 33% had at least one sign or symptom.10–16 Pain is the most important symptom in temporomandibular joint dysfunction (TMD) for both the patient and the clinician, and is the main reason why patients with TMJ disease seek medical help.17 According to some researchers, it is commonly accepted that TMD is of multifactorial origin and is best thought of as the result of a combination of occlusal, neurophysiologic, and psychological factors.18 Low self esteem was associated with more prevalent TMD findings.19 Psychological and emotional features are obviously linked with the prevalence of TMD findings.20,21 Based on psychometric differences, it is currently justified to subcategorize patients with myofascial pain dysfunction into a myogenic pain group and a TMJ-related pain group.22 Temporomandibular dysfunction might influence any individual with different signs and symptoms irrespective of gender12 or age, including children.23 Proffit and Fields24 claimed that there was female preponderance in TMJ discomfort, and that TMJ discomfort occurred more in persons with a history of jaw trauma. Some researchers claimed that university students (18–25 years old) had higher prevalence of TMD symptoms than older subjects25 and populations of rural areas.26 Symptoms of TMD were remarkably prevalent among samples representative of the student community in Jordan and Brazil.7,27 Not enough data are available regarding prevalence of TMJ symptoms among university students in Saudi. Therefore, this study was conducted to investigate prevalence of TMD among university students from north Saudi Arabia, using the guidelines recommended by the American Dental Association, and to compare the prevalence of TMD among students from different faculties, in an attempt to recognize the risk groups for TMD development. The Null hypothesis was that TMD is not prevalent among university students, and that students from different faculties have similar TMD prevalence.
The study was approved by Deanship of Research, Aljouf University, Sakaka, Saudi Arabia. Each participant was provided with a full explanation of the study and how to complete the required questionnaire. Participants’ written informed consent was obtained before being recruited into the study. To be included in the study, participants had to be university students, have no medical or mental issues that affected their ability to comprehend or complete the questionnaire, have no dental pain, have no bony lesions in the jaws, and have no problems related to third molar eruption. All participants were examined under a dental unit light using a dental mirror, and had an orthopantographic radiograph (OPG), in order to rule out any bony lesion, any problem related to third molar eruption, or any dental related disease that could cause pain or findings confused with TMD. Participants with problems related to dental disease, bony lesions, or third molar eruption were excluded from the study. In total, 489 students (346 males and 143 females) were recruited into the study. Participants’ age range was from 18 to 25 years old (mean520.8 years old, SD51.7 years). First-year students formed 33.1% of the sample (162 students), while 30.3% (148 students) of the sample were second-year students, 22.1% (108 students) were third-year students, 13.5% (66 students) were fourth-year students, and 1% (5 students) were fifth-year students. Moreover, 304 (62.2%) of the participants were studying at humanitarian colleges, 95 (19.4%) were health college students, and 90 (18.4%) were science college students. A questionnaire was constructed and dispensed randomly to participants (Appendix 1). There was no time limit for completion of the questionnaire, so there was no reason for the subject to give induced answers. The completed questionnaire contained items regarding the different symptoms of TMD and the possible risk factors. Statistical analysis was carried out using SPSS software (Version 19.0, SPSS Inc., Chicago, IL, USA). Pearson correlation test was used to find out the relationships between the TMD findings and independent factors. To identify potential confounding variables for the TMD findings, a stepwise multivariate logistic regression was utilized. Probability values were set at Pj0.05.
Results Materials and Methods The study sample was derived from officially registered students studying at Aljouf University. 2
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Table 1 presents the prevalence of different TMD findings among the study sample. Clicking was the most prevalent TMD finding among the study VOL .
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Table 1 The prevalence of various findings of TMD in the study population according to gender and field of study (n5489). Number of respondents Health and Science
Humanitarian
TMD findings
Male
Female
Male
Female
Total prevalence (%)
Clicking Pain on or about ear Difficulty with chewing Limitation in mouth opening Pain on chewing
20 19 11 12 6
21 25 15 5 12
77 61 44 32 17
25 13 10 14 3
29.2 24 16.4 12.9 7.8
TMD: temporomandibular disorder.
population. Pain in or about the ears or cheeks was less prevalent than clicking, meanwhile pain during chewing was the least prevalent finding (Table 1). Nearly half of the participants (246 students) reported no TMD findings, while 49.7% (243) of them had one or more finding. Among those who had TMD findings, 24.3% (119 students) had one symptom, while 0.4% (2 students) had five coexisting TMD findings (Table 2). The five symptoms of TMD were found to be significantly associated and occurred together (Pv0.05). Females had more TMD findings than males (r50.509, P50.000). Also, there were significant correlations between TMD findings and field of study (r50.197, P50.000); TMD findings were significantly more prevalent among students from science and health colleges, while the least prevalent findings were reported by students from humanitarian colleges. Temporomandibular disorder findings were more prevalent among students who experienced trauma to the maxillofacial area (r50.166, P50.000), or who were unsatisfied with their appearance or study achievement (r50.143, P50.002). Moreover, TMD symptoms were more prevalent among participants who suffer clenching (r50.122, P50.007) or limited mouth opening (r50.126, P50.005). A stepwise multivariate logistic regression analysis showed that pain, clicking, limited mouth opening, and bruxism had strong associations with the presence of TMD (Pv0.05) (Table 3). The multicollinearity within the regression model (the correlation between the
Table 2 The prevalence of concurrent TMD symptoms in the study population Number of concurrent symptoms 5 4 3 2 1 TMD: temporomandibular disorder.
Number of respondents (%) 2 (0.4) 17 (3.5) 35 (7.2) 70 (14.3) 119 (24.3)
independent variables within the regression model) was tested, and revealed that the tolerance value was larger than 0.1 and the variance inflation factor (VIF) was less than 10 for all variables (Table 3). No significant correlation between the independent variables was found, and thus the variables do not depend on each other and do not measure the same concept. This ensures the accuracy of the calculated model, where pain, clicking, limited mouth opening, and bruxism had strong associations with the presence of TMD.
Discussion This study found that university students in north Saudi Arabia reported a high prevalence of TMD. Also, students from science and health colleges reported a higher prevalence of TMD findings than humanitarian college students. Therefore, the null hypothesis was rejected. This study showed that TMD findings were common among the study sample of North Saudi students at Aljouf University. This is in harmony with findings of previous studies on Brazilian27 and Jordanian7 university students. Clicking was the most common TMD finding in this investigation, which agrees with the findings of previous studies.16,28 Also, periauricular pain was found to be the second most common symptom among the participants, and this contrasts with some studies7 that reported periauricular pain as the most common symptom of TMD. In the current study, female participants reported a higher prevalence of TMD findings than males; a finding that is in agreement with the results of earlier investigations.3,27 Also, in this study, science and health college students reported more TMD findings. The reasons behind this could be the larger study load that associates their courses, the higher competition required for admission to science and health colleges in comparison to humanitarian colleges, and the
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Table 3 Stepwise logistic regression for findings of TMD Collinearity statistics TMD findings
Standardized coefficients beta
T
P-value
Clicking on yawning Clicking after awaking Pain after awaking Pain during eating Pain under stress Pain during yawning Pain during speaking Difficulty in mouth opening Bruxism
0.071 0.052 0.315 0.320 0.237 0.407 0.109 {0.046 0.081
2.730 2.027 13.536 13.662 9.101 15.694 4.661 {1.986 3.496
0.007 0.043 0.000 0.000 0.000 0.000 0.000 0.048 0.001
Tolerance 0.732 0.766 0.918 0.904 0.732 0.738 0.913 0.921 0.932
VIF 1.367 1.306 1.090 1.106 1.366 1.355 1.095 1.086 1.073
Predictors: TMD findings, Dependant variable5TMD incidence, R square50.774, Standard error of the estimate50.20623. VIF: variance inflation factor; TMD: temporomandibular disorder.
possibility of higher levels of stress and anxiety among science and health students. In the present study, TMD findings were significantly related to emotional and psychological features. This result concurs with the findings of earlier investigations.29,30 Trauma to the maxillofacial region was significantly related to TMD findings among the study sample; this concurs with the results of previous studies that associated trauma with TMD findings.31 The results of this investigation highlight the need for additional research to shed more light on the risk factors and findings related to TMD. This will facilitate drawing adequate guidelines for prevention and management of TMD. Also, the findings of this study support the idea of conducting regular examinations for university students in order to allow early diagnosis and prompt management of TMD. Study limitations include the use of questionnaires to investigate symptoms of TMD, which is a subjective method of research. However, every attempt was made to adequately explain the questionnaire and the study to the participants, and participants were given no time limits to complete the questionnaires. Additionally, the number of selected students in each year was not similar, due to variations in the number of students in each year and variations in acceptance to participate in the study between students from different years of study. This could affect the obtained results. However, since the students were of a similar age group, the effect of this point on the results would not undermine the results of this study, and this was the reason why the relationship exists between prevalence of TMD findings and year of study. This could be an area for further research. No studies were found in the literature on TMD findings among individuals who are non-university students and of similar age group to university 4
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students. This could be because it is difficult to find subjects who are in the same age group, but not university or college students. Therefore, it was not possible to compare the results of this investigation to non-university students of a similar age group. However, previous studies on university students did not use controls of a similar age and did not study non-university students who are of the same age of university students. This could be an area for future research. Further studies are also required on larger samples and different populations to identify the effects of racial and cultural backgrounds on the development of TMD.
Conclusions Within the limitations of this investigation, it was concluded that university students in north Saudi Arabia reported a high prevalence of TMD. Also, students from science and health colleges reported a higher prevalence of TMD findings than humanitarian college students. Clicking and pain were the most prevalent findings of TMD among the study sample.
Acknowledgements The authors would like to thank Aljouf University for supporting this research (Reference number 34/171).
Disclaimer Statements Contributors Prof Mahmoud Al-Omiri: conceived and designed the study, obtained funding and ethical approval, collected the data, analyzed and interpreted the data, and wrote and revised the article. Dr Abdalwhab M. A. Zwiri: conceived and designed the study, obtained funding and ethical approval, collected the data, interpreted the data, and wrote and revised the article. Funding Aljouf University, Sakaka, Saudi Arabia. VOL .
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Conflicts of interest The authors have no conflict of interest. Ethics approval Ethical approval was obtained by Deanship of Research, Aljouf University, Sakaka, Saudi Arabia. Reference number 34/171.
Appendix 1: The Questionnaire Used in this Study (1) Do you usually hear a click at your temporomandibular joint? Yes % No % (2) When do you usually hear the click? (3) Is your click painful? Yes % No % (4) Do you know anyone with TMD? Yes % No % (5) Have you ever sought treatment for pain or click in your joint? Yes % No % (6) Do you have chewing difficulty? Yes % No % (7) Do you usually feel pain at your temporomandibular joint? Yes % No % (1) % After awaking Yes % No % (2) % During eating Yes % No % (3) % When under stress Yes % No % (4) % During yawning Yes % No % (5) % During speaking Yes % No % (6) % All the time Yes % No % (8) Do you usually complain of headache? Yes % No % (9) Do you usually complain of pain in the neck? Yes % No % (10) Do you usually complain of pain in the shoulders? Yes % No % (11) Have you ever had difficulty in opening your mouth? Yes % No % (12) Do you usually clench your teeth during day time? Yes % No % (13) Do people hear your bruxism sound at night? Yes % No % (14) Do you usually use any of the following?
Chewing gum Yes % No % Nuts Yes % No % Long phone call Yes % No % The habit of biting on a hard objects (e.g. pencil) Yes % No % (15) Have you ever had any of the following? Trauma to the chin or face Yes % No % Subjected to a lengthy extraction of posterior teeth or Lengthy dental appointment Yes % No % Missing posterior teeth Yes % No % Orthodontic treatment Yes % No % (16) Are you satisfied with your: Accomplishment in the university Yes % No % Appearance Yes % No % Life style Yes % No % (17) Do you have any sleeping disorder (not getting enough sleep) Yes % No %
Prevalence of temporomandibular joint disorder
(18) Do you complain of any of the following diseases?
Rheumatoid arthritis Yes % No % Lupus erythematousus Yes % No % Psoriasis Yes % No % Hypermobility of joints disorder Yes % No % Gout Yes % No % Reflux (heartburn) Yes % No % Low back pain Yes % No %
References 1 Sari S, Sonmez H. Investigation of the relationship between oral parafunctions and temporomandibular joint dysfunction in Turkish children with mixed and permanent dentition. J Oral Rehabil. 2002;29:108–12. 2 James BA. Costen syndrome of ear and sinus symptoms dependent upon disturbed function of the temporomandibular joint. Ann Otol Rhinol Laryngol. 1934;43:1–15. 3 Roda RP, Jose´ V, Baga´n JV, Ferna´ndez JMD, Baza´n SH, Soriano YJ. Review of temporomandibular joint pathology. Part I: classification, epidemiology and risk factors. Med Oral Patol Oral Cir Bucal. 2007;12:E292–8. 4 Laskin D, Greenfield W, Gale E. The president’s conference on the examination, diagnosis and management of temporomandibular disorders. Chicago: American Dental Association; 1983. 5 Luther F. Orthodontics and the temporomandibular joint: where are we now? Part I. Orthodontic treatment and temporomandibular disorders. Angle Orthod. 1998;68:295–304. 6 McNeill C. Management of temporomandibular disorders: concepts and controversies. J Prosthet Dent. 1997;77:510–22. 7 Ryalat S, Baqain ZH, Amin W, Sawair F, Samara O, Badran DH. Prevalence of temporomandibular joint disorders among students of the University of Jordan. J Clin Med Res. 2009;1:158–64. 8 Leresche L. Epidemiology of temporomandibular disorders: implications for the investigation of etiologic factors. Critical Rev Oral Biol Med. 1997;8:291–305. 9 Cooper BC, Kleinberg I. Examination of a large patient population for the presence of symptoms and signs of temporomandibular disorders. J Craniomandib Pract. 2007;25:114–26. 10 Solberg WK. Temporomandibular disorders: background and the clinical problem. Br Dent J. 1986;160:157–67. 11 Schiffman EL, Fricton JR, Haley DP, Shapiro BL. The prevalence and treatment needs of subjects with temporomandibular disorders. J Am Dent Assoc. 1990;120:295–303. 12 Nassif NJ, Hilsen KL. Screening for temporomandibular disorders: history and clinical examination. American Dental Association. J Prosthodont. 1992;1:42–6. 13 McNeill C, editor. Temporomandibular disorders. Guidelines for classification, assessment and management. 2nd edn. London: The Academy of Orofacial Pain, Quintessence; 1993. 14 Carlsson GE, Magnusson T, editors. Management of temporomandibular disorders in the general dental practice. London: Quintessence; 1999; p. 13–17. 15 Chuang SY. Incidence of temporomandibular disorders (TMDs) in senior dental students in Taiwan. J Oral Rehabil. 2002;29:1206–11. 16 Okeson JP, editor. Management of temporomandibular disorders and occlusion. 3rd edn. St. Louis: Mosby; 2003; p. 413–35. 17 Roda RP, Ferna´ndez JMD, Baza´n SH, Soriano YJ, Margaix M, Sarrio´n G. A review of temporomandibular joint disease (TMJD). Part II: clinical and radiological semiology morbidity processes. Med Oral Patol Oral Cir Bucal. 2008;13:E102–9. 18 Moss RA, Garret J, Chiodo JF. Temporomandibular joint dysfunction and myofacial pain dysfunction syndromes: parameters etiology and treatment. Psychol Bull. 1982;92:331–46. 19 Godoy F, Rosenblatt A, Godoy-Bezerra J. Temporomandibular disorders and associated factors in Brazilian teenagers: a cross-sectional study. Int J Prosthodont. 2007;20:599–604. 20 Gerke DC, Goss AN, Bassett DL. Psychological factors in temporomandibular joint dysfunction: life events. Aust Prosthodont J. 1990;4:29–34. 21 Manfredini D, Landi N, Bandettini Di Poggio A, Dell’Osso L, Bosco M. A critical review on the importance of psychological
CRANIOt: The Journal of Craniomandibular & Sleep Practice
2015
VOL .
00
NO .
0
5
Zwiri and Al-Omiri
22 23 24 25 26
6
Prevalence of temporomandibular joint disorder
factors in temporomandibular disorders. Minerva Stomatol. 2003;52:321–30. Dahlstrom WG, Welsh GS, Dahlstrom LE. An MMPI handbook, Vol II, clinical interpretation. Minneapolis: University of Minnesota Press; 1972. Nilner M, Lassing SA. Prevalence of functional disturbances and diseases of the stomatognathic system in 7-14 year olds. Swed Dent J. 1981;5:173–87. In: Proffit WR, Fields HW, editors. Contemporary orthodontics. 3rd edn. St. Louis: Mosby; 2000; p. 201–8. Osterberg T, Carlsson GE, Wedel A, Johansson U. A cross-sectional and longitudinal study of craniomandibular dysfunction in an elderly population. J Craniomandib Disord. 1992;6:237–45. Goddard G, Karibe H. TMD prevalence in rural and urban Native American populations. J Craniomandib Pract. 2002;20:125–8.
CRANIOt: The Journal of Craniomandibular & Sleep Practice
2015
27 Pedroni CR, De Oliveira AS, Guaratini MI. Prevalence study of signs and symptoms of temporomandibular disorders in university students. J Oral Rehabil. 2003;30:283–9. 28 Shiau YY, Chang C. An epidemiological study of temporomandibular disorders in university students of Taiwan. Community Dent Oral Epidemiol. 1992;20:43–7. 29 Filho J, Manzi FR, de Freitas DQ, Boscolo FN, de Almeida SM. Evaluation of temporomandibular joint in stress free patients. Dentomaxillofac Radiol. 2007;36:336–40. 30 Speculand B, Hughes AO, Goss AN. Role of recent stressful life events experience in the onset of TMJ dysfunction pain. Community Dent Oral Epidemiol. 1984;12:197–202. 31 Klobas L, Tegelberg A, Axelsson S. Symptoms and signs of temporomandibular disorders in individuals with chronic whiplash-associated disorders. Swed Dent J. 2004;28:29–36.
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