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Acta Odontológica Latinoamericana

versión On-line ISSN 1852-4834

Acta odontol. latinoam. vol.29 no.3 Buenos Aires dic. 2016



Assessment of knowledge on temporomandibular disorders among Mexican dental educators


Irene A. Espinosa1, Edgar M. Pérez1, Yoly M. Gonzalez2, Alejandro Corona3

1 School of Stomatology, Benemerita Universidad Autonoma de Puebla, México
2 Department of Oral Diagnostic Sciences, State University New York at Buffalo, USA
3 Undergraduate Student in Psychology, State University New York at Buffalo, USA

CORRESPONDENCE: Dr. Irene Aurora Espinosa Tlacomulco 4513, Col. Ampliacion Reforma Sur. CP 72160 Puebla, Pue. Mexico.


Temporomandibular disorders (TMDs) is an umbrella term that embraces a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints, muscles and all associated tissues. Because of the relatively high number of patients with TMDs in the population, instruction in this area of health care should be included on all dental curricula. Although levels of knowledge among dentists have been evaluated in several countries, they have not been in Mexico. This study evaluates the dental faculty's range of knowledge about TMD at five dental schools in Puebla, Mexico. Using an observational design, a survey was administered to 161 educators in order to assess their knowledge of TMD. Four domains were assessed, including: a) pathophysiology; b) psychophysiology; c) psychiatric disorders; and d) chronic pain. Overall knowledge of TMD was measured using a consensus of TMD experts' answers as a reference standard1The results show that educators' overall knowledge had 55% agreement with the reference standard. Individually, the psychophysiological domain was correctly recognized by 77.7% of the educators; correct responses on the other domains ranged from 38% to 56%. This study demonstrates the need to incorporate standardized TMDs instruction into the dental curricula at Mexican Universities, without which graduating dentists will lack the necessary knowledge or experience to diagnose and manage their TMD patients.

Key words: Temporomandibular joint disorders; Dental education; Teaching.


Evauación del conocimiento sobre trastornos temporomandibulares en docentes de odontología en México

Los Trastornos Témporomandibulares (TTM) incluyen un grupo de condiciones musculoes que léticas y neuromusculares que afectan a la Articulación Temporomandibular (ATM), los músculos masticadores y otros tejidos asociados. Debido al número relativamente alto de pacientes con TTM en la población, la educación en esta área de la salud debe ser incluida en las currículas de las escuelas de odontología. A pesar de que el nivel de conocimiento sobre TTM ha sido evaluado en diversos países, esto no ha sido realizado en México, por lo que el objetivo del presente estudio fue evaluar el nivel de conocimiento sobre los TTM de los profesores de odontología en cinco universidades de Puebla, México. Bajo un diseño observacional, se administró una encuesta a 161 docentes de odontología para evaluar el nivel de conocimiento sobre los TTM. La encuesta incluyó cuatro dominios: a) patofisiología; b) psicofisiología; c) trastornos psiquiátricos y d) dolor crónico. Se usaron las respuestas otorgadas con un consenso de expertos como estándar de referencia1 para evaluar el nivel global de conocimiento sobre los TTM. Los resultados mostraron que los docentes tuvieron un nivel global de conocimiento del 55% de acuerdo al estándar de referencia. El dominio psicofisiológico indivi dualmente fue el mejor reconocido con el 77% de acuerdo con los expertos; las respuestas correctas en los otros dominios oscilaron entre el 38% y el 56%. El presente estudio demostró la necesidad de incorporar educación sobre los TTM estandarizada en la currícula de las escuelas o facultades de odontología en las universidades mexicanas. Hasta que esto suceda, las generaciones de odontólogos no tienen el conocimiento ni la experiencia necesarios para diagnosticar y manejar a los pacientes con Trastornos Temporomandibulares.

Palabras clave: Trastornos Temporomandibulares; Educación dental; Enseñanza.



Temporomandibular disorders are recognized by the American Association of Dental Research (AADR) as a collective term that embraces a group of musculoskeletal and neuromuscular conditions that involve the temporomandibular joints, the muscles and all associated tissues 2. TMDs have been identified as a major cause of nondental pain in the orofacial region and are considered to be a subclassification of musculoskeletal disorders 3. It has been speculated that the onset of TMD is complex and multifactorial, and such factors have been classified as predisposing, precipitating and perpetuating 4. The reported prevalence of TMD, according to populationbased studies, ranges from 6.3% to 15% in women and 2.8% to 10% in men. TMD conditions have been found to have an agespecific pattern, peaking at 35 to 45 years of age 5-10. Studies have shown that the prevalence of signs or symptoms associated to TMD can be observed in up to 50% of the general population, of which only 3% to 7% seek professional help, depending on the severity of their symptoms 5. Additionally, it has been demonstrated that patients with more than one TMD diagnosis have a greater chronicity as well as greater psychosocial involvement 10-13.
In the United States, there have been several attempts to improve education in this field. Since 1990, the First Educational Conference to Develop the Curriculum in Temporomandibular Disorders and Orofacial Pain proposed several curriculum models specifically for predoctoral, postdoctoral, and continuing education 14-22. A second educational conference was held in 1992, at which the educational methodologies for the implementation of formal curriculum guidelines in dental education, problembased learning, decision analysis, and computer technology were discussed 23. Finally, in 2000, the Third Educational Conference was held, sponsored by the American Academy of Orofacial Pain, the Association of University TMD and Orofacial Pain Programs, the American Academy of Oral Medicine, the Canadian Academy of Oral and Maxillofacial Pathology and Oral Medicine, and the Association of Canadian Faculties of Dentistry. Over 130 educators participated with the goal of improving the teaching of TMD and OFP at predoctoral level 23,24.
Today, TMDs are being studied and treated with a medical perspective that involves orthopedic principles combined with a biopsychosocial understanding of how chronic pain disorders affect those who suffer them 25,26. Despite this progress, there are still controversies among those in the field of dental and advanced dental education. LeResche et al. 1 evaluated the extent of knowledge of TMD in a random sample of general dentists and TMD specialists. They reported that practicing dentists tended to agree with the opinion of experts on psychophysiological aspects, but they generally disagreed on issues related to the domain of pathophysiology. The study concluded that there is a high degree of consensus in knowledge among specialists and general dentists on some items; however, there is a need to reach a more consistent consensus among all domains.
Based on the information presented above, there is no doubt that teaching TMD should be a fundamental component of the dental curriculum, not only at the didactic level, but also incorporated into the student's clinical experiences, which influence knowledge and skills for treating TMD patients 13,15,26,27-32. As far as we know, there is no published study evaluating the knowledge of dental educators or clinicians in the area of TMD in Mexico. Therefore, the aim of this study was to evaluate knowledge of TMD among dental educators at five dental schools in Puebla, Mexico.


An observational, crosssectional study was conducted on 161 dental educators from five, out of a total of twentyone, dental schools in the city of Puebla, Mexico. All twentyone universities were invited to participate, but only 5 accepted to participate voluntarily and obtained approval from the relevant institutions. A published survey conducted in Seattle was used as reference1 in which thirteen researchers who publish extensively in the refereed TMD literature formed the TMD expert group. These experts belonged to the International Association for Dental Research (IADR) and/or the International Association for the Study of Pain (IASP), and all had extensive clinical and/or research experience with TMD patients. The Seattle study was translated and adapted by an expert panel into Spanish. This survey consisted of 35 items divided into four domains: a) pathophysiology: assessing knowledge of biomedical or biomechanical aspects of TMD etiology, diagnosis and treatment, b) psychophysiology: assessing knowledge of the interaction of physical and psychological factors in TMD etiology, diagnosis and treatment, c) psychiatric disorders: assessing knowledge about anxiety, depression and somatization disorders associated with TMD, and d) chronic pain: assessing knowledge about the causes, diagnosis and appropriate treatment of chronic pain conditions as applied to TMD, according with survey proposal by LeResche et al 1.
In the original Seattle study, the statements were evaluated by panels of experts. The expert responses used in the Seattle study were also used for the present study. The statements were said to generate expert consensus if more than 75% of the experts in the designated group endorsed an “agree” response (scored 7 to 10) or a “disagree” response (scored 0 to 3).
The answers were considered “correct” if the response matched the reference standard or response provided by the consensus of TMD experts. Otherwise, the responses were considered “incorrect”, even those in which the participants answered “I don't know”. All the participants answered the survey at their respective institutions in the presence of the researcher.

Statistical Analysis
Descriptive statistics including mean, median, standard deviation (SD), and percentages are presented. In addition, the median percentage of correct responses for each domain and total instrument scores were calculated. Comparisons by gender and by year of graduation from dental school were performed using the MannWhitney test. Comparison by academic level was performed using the Kruskal Wallis test. A significance α level of 0.05 was used. SPSS version 17 was used for the statistical analysis. The dependent variable was TMD knowledge in dental educators. The independent variables were: gender, academic level, and year of graduation.


A total 161 dental educators participated in this study. Mean age was 40 years with a standard deviation of 10 years. Gender distribution was 55% female and 45% male. Regarding academic level, 24% were general dentists, 37% had a clinical specialty (not specifically TMD), and 39% had either an MS or PhD degree.
In the first domain (pathophysiology), the median percentage of correct responses by dental educators was 38% (Table 1). Within this domain, the item with the lowest rate of correct responses was “Occlusal equilibration is a useful early treatment for TMD”, for which only 2,5% of educators had
adequate knowledge. The item with the highest number of correct responses in the same domain was “Nocturnal bruxism is caused by occlusal interferences”, for which 68% of educators had adequate knowledge. This particular domain presented a wide range of variability.

Table 1: Pathophysiology Domain.

In the second domain (psychophysiology), dental educators had better knowledge of the subject, and the median percentage of total correct answers was 78% (Table 2).Within this domain, the item with the lowest rate of correct answers was “Stress is a major factor in the development of TMD”, with only 47% of the educators demonstrating adequate knowledge. The item with the highest percentage of correct answers was “Stress management is indicated for many TMD patients”, with 88% of the educators having adequate knowledge. In the third domain (psychiatric disorders), the median percentage of total correct answers by dental educators was 50% (Table 3). The item with the lowest rate of correct answers was “Clinical depression is rare in chronic TMD patients”, with only 47% of educators having adequate knowledge. The item with the highest percentage of correct answers in this domain was “Depression can be an important etiologic factor in chronic pain”, with 62% of educators demonstrating adequate knowledge.

Table 2: Psychophysiologic Domain.

Table 3: Psychiatric Disorders Domain.

Finally, in the fourth domain (chronic pain), the median percentage of correct answers was 56% (Table 4). Within this domain, the item with the lowest rate of correct answers was “Prescription of narcotics, as needed for pain as treatment of choice when TMD pain is severe”, where only 26% of the participants had adequate knowledge. The item with the highest rate of correct answers in this domain was “Behavior modification treatments are appropriate for patients with chronic TMD pain”, where 63% of dental educators agreed with experts on TMD.

Table 4: Chronic Pain Domain.

Comparison by gender (Table 5), year of graduation (Table 6), and academic level (Table 7) showed no statistically significant difference among groups (p>0.05).

Table 5: Comparison by gender.

Table 6: Comparison by time that the educators finished the last academic level.

Table 7: Comparison by academic level.


This research shows that participating dental educators' knowledge ofTMD differs greatly from the knowledge of experts in TMD reported in the literature1,33. Several countrieshave made efforts to assess knowledge of TMD among dentists1,25,31-36,38,39. Researchers have shown that even among professionals with advanced education in TMD, there is no homogeneity of concepts on the pathophysiology of these conditions 1,34,36-38. In Mexico there is no specialty in TMD, and patients with this condition are treated by specialists in different areas of stomatology and general dentists. This study represents the first evaluation conducted in Mexico, and clearly indicated the inconsistency of knowledge and understanding of these disorders, and consequently, the low priority that has being assigned to the field of TMD in dental education. We believe that this study highlights the need for dental educators to be prepared and teach the most updated knowledge in the field to their dental students.
Our results are consistent with data previously reported by several researchers. No difference was found by gender, academic level and year of graduation1,35. This is also consistent with Glaros et al 33 who claims that general dentists and specialists in areas other than the TMD do not differ in knowledge about these disorders. However, other authors have found controversial results, with specialists obtaining better scores 34. Our data are also consistent with previously reported results on the pathophysiological domain, representing the lowest rate of 38% 1,33,35,38. The results illustrate a poor understanding of the etiology, diagnosis, and treatment of TMD. Our research showed the greatest weakness (only 2.5% of correct answers according to the experts) is in the belief that occlusal balance is a useful option in early treatment of temporomandibular disorders. Occlusal equilibrations are still being used in Mexico for the early management of patients with TMD, despite the vast worldwide evidence against such treatment. This particular finding contrasts with values from other previously reported studies in which the percentage of agreement of general dentists and other specialists was about 30% and 26%1,33. On the other hand, the correct percentage, according to the experts in this research, about the statement “orthodontic treatment can prevent TMD” (21%), was slightly lower in studies by Glaros et al 33 (19%) and Le Resche 1(14%), although all results are low.
Conversely, it is noteworthy that the domain of psychophysiology (mechanisms of acute and chronic pain, biofeedback, oral parafunctional habits, stress, etc.) in the etiology of temporomandibular disorders was well recognized by the participants (78%). This highlights the understanding of most educators of the role of psychophysiological factors in the field of TMD. Previous studies 1,33 have shown correct knowledge of this domain in 50% to 90% of general dentists and other specialists, consistent with the results of our study (46% to 88%).With respect to the domain of psychiatric disorders, our study has found that depression and anxiety are recognized as determining factors in patients with TMD, with 52% to 62% of participants answering those items correctly. Studies by Le Resche1 and Glaros33 found success rates higher than those reported in our study. Finally, domain analysis of chronic pain denotes that participants have acceptable knowledge of said domain (55%). However, issues such as “PRN narcotics (i.e., “as needed” for pain) are a treatment of choice when TMD pain is severe” and “Chronic pain is a behavioral as well as a
physical problem”, remain poorly understood by participants. Despite the high prevalence of TMD reported in the literature, knowledge of TMD among dental educators needs improvement, as previous studies have reported 1,33,34,37,38. The results denote a high level of variability in the domain of the pathophysiology diagnosis and treatment as well as a need to improve in the other domains. Knowledge among educators is not influenced by gender, academic level, or year of graduation. These results support the conclusion that there is an important need for improvement in the knowledge of TMD in the dental educational system in Puebla, Mexico.


The authors would like to thank the Benemerita Universidad Autonoma de Puebla and the Consejo Nacional de Ciencia y Tecnologia (CONACYT) for providing financial support for PhD. Irene Espinosa during her International Scholarship Award, and for Mauricio Perez during his Master's studies.


1. Le Resche L, Truelove EL, Dworkin SF. Temporomandibular disorders: a survey dentists' knowledge and beliefs. J Am Dent Assoc 1993; 124:97-106.         [ Links ]

2. Greene CS. Managing the care of patients with temporoman di bu lar disorders: a new guideline for care. J Am Dent Assoc 2010; 141:1086-1088.         [ Links ]

3. De Leeuw R. Orofacial Pain Guidelines for Assessment, Diagnosis and Management.Quintessence Books. 4th ed. Chicago, USA: The American Academy of Orofacial Pain, 2008:131-132.         [ Links ]

4. Okeson JP. Management of temporomandibular disorders and occlusion. 5th ed. St Louis: Mosby, 2003:143-189.         [ Links ]

5. Le Resche L. Epidemiology of Temporomandibular Disorders: Implications for the Investigation of Etiologic Factors. Crit Rev Oral Biol Med 1997; 8:291-305.         [ Links ]

6. Isong U, Gansky S, Plesh O. Temporomandibular joint and muscle disordertype pain in the US adults: the National Health Interview Survey. J Orofac Pain 2008; 22:317-322.         [ Links ]

7. National Institute of Dental and Craniofacial Research Facial Pain. 2010. NIH Publication No. 10-3487.: URL:        [ Links ]

8. Gonzalez YM. Are temporomandibular disorders a public health problem? Alpha Omegan 2003;96:11-14        [ Links ]

9. Sessle JB, Lavigne JG, Lund JP. Orofacial Pain From Basic Sciences to Clinical Management. 1st ed. Chicago: Quintessence Book, 2001:17-19.         [ Links ]

10. Slade GD, Bair E, Kunthel B, Mulkey F, Baraian C, Rothwell R, Reynolds M, Miller V, et al. Study Methods, Recruitment, Sociodemographic Findings, and Demographic Representativeness in the OPPERA Study. J Pain 2011; 12:T12–T26.         [ Links ]

11. Espinosa SI, Lara MC, Lara CA, Saavedra GM, Vargas GH. Comparacion de losaspectospsicosociales (eje II) de los pacientes con trastornos teporomandibulares, de acuerdo a la combinacion de diagnosticosfisicos (eje I) de los criterios diagnosticos para la investigacion de los trastornos tempo romandibulares (CDI/TTM). Rev Oral 2009;10: 477-481. URL:        [ Links ]

12. Slade GD, Diatchenko L, Bhalang K, Sigurdsson A, Fillingim RB, Belfer I, Max MB, Goldman D, et al. Influence of psychological factors on risk of temporoman dibular disorders. J Dent Res 2007; 86:1120-1125.         [ Links ]

13. Klasser GD, Greene CS. Predoctoral teaching of temporo mandibular disorders: a survey of U.S. and Canadian dental schools. J Am Dent Assoc 2007; 138:231-237.         [ Links ]

14. Gontyy AA.Teaching a comprehensive orofacial pain course in the dental curriculum. J Dent Educ 1990; 54:319-322.         [ Links ]

15. Solberg WK, Fricton JR. The role of the dental school in teaching TMD and orofacial pain. J Craniomandib Disord 1992; 6:107-110.         [ Links ]

16. Greene CS, Stockstill JW, Clark GT. Predoctoral education for TMD and orofacial pain: a philosophical overview. J Craniomandib Disord 1992; 6:111-112.         [ Links ]

17. Attanasio R, Mohl ND. Suggested curriculum guidelines for the development of predoctoral programs in TMD and orofacial pain. J Craniomandib Disord 1992; 6:113-116.         [ Links ]

18. Attanasio R, Mohl ND. Suggested curriculum guidelines for the development of continuing education programs in TMD and orofacial pain. J Craniomandib Disord 1992; 6:137-140.         [ Links ]

19. Attanasio R, Mohl ND. Suggested curriculum guidelines for the development of postdoctoral programs in TMD and orofacial pain. J Craniomandib Disord 1992; 6:126-134.         [ Links ]

20. Stockstill JW. Curriculum outline for adjunctive predoctoral education in TMD and orofacial pain. J Craniomandib Disord 1992; 6:117-122.         [ Links ]

21. Fricton JR, Pullinger AG, Mohl ND. Postdoctoral education for TMD and orofacial pain. A philosophical overview. J Craniomandib Disord 1992; 6:123-125.         [ Links ]

22. McNeill C, Falace D, Attanasio R. Continuing education for TMD and orofacial pain: a philosophical overview. J Craniomandib Disord 1992; 6:135-136.         [ Links ]

23. Mohl ND, Attanasio R. The Third Educational Conference to Develop the Curriculum in Temporomandibular Disorders and Orofacial Pain: introduction. J Orofac Pain 2002;16: 1731-75.         [ Links ]

24. Mohl ND. The Third Educational Conference to Develop the Curriculum in Temporomandibular Disorders and Orofacial pain: Summary/Conclusions. J Orofac Pain 2002; 16:198-199.         [ Links ]

25. Shankland W. Temporomandibular disorders: standard treatment options. Gen Dent 2004; 52:349-355.         [ Links ]

26. Klasser GD, Greene CS. The changing field of temporo man di bular disorders: what dentists need to know? J Can Dent Assoc 2009; 75:49-53.         [ Links ]

27. McKinney JF, Mosby EL. Temporomandibular disorders: what to teach in dental school. J Craniomandib Disord 1990; 4:17-19.         [ Links ]

28. Douglass GD. Making a comprehensive diagnosis in a comprehensive care curriculum. J Dent Educ 2002; 66:414-420.         [ Links ]

29. Gonzalez Y, Mohl ND. Care of patients with temporoman di bular disorders: an educational challenge. J Orofac Pain 2002;16:200-206.         [ Links ]

30. Alsafi Z, Michelotti A, Ohrbach R, Nilner M, List T. Achieved competences in temporomandibular disorders/ orofacial pain: a comparison between two dental schools in Europe. Eur J Dent Educ 2015;19:161-168.         [ Links ]

31. Al-Khotani A, Bjornsson O, Naimi-Akbar A, Christidis N, Alstergren P. Study on selfassessment regarding knowledge of temporomandibular disorders in children/adolescents by Swedish and Saudi Arabian dentist. Acta Odontol Scand 2015; 73:522-529.         [ Links ]

32. Alonso AA, Heima M, Lang LA, Teich ST. Dental students' perceived level of competence in orofacial pain. J Dent Educ 2014; 78:1379-1387.         [ Links ]

33. Glaros AG, Glass EG, McLaughlin L. Knowledge and beliefs of dentists regarding temporomandibular disorders and chronic pain. J Orofac Pain 1994; 8:216-222.         [ Links ]

34. Baharvand M, Sedaghat Monfared M, Hamian M, Jalali Moghaddam E, Sadat Hosseini F, Alavi KA. Temporo mandibular disorders: knowledge, attitude and practice among dentists in Tehran, Iran. J Dent Res Dent Clin Prospect 2010; 4:90-94.         [ Links ]

35. Just JK, Perry HT, Greene CS. Treating TM disorders: a survey on diagnosis, etiology and management. J Am Dent Assoc 1991; 122:55-60.         [ Links ]

36. Tegelberg A, Wenneberg B, List T. General practice dentists' knowledge of temporomandibular disorders in children and adolescents. Eur J Dent Educ. 2007; 11:216-221.         [ Links ]

37. Patil S, Iyengar AR, Ramneek. Assessment of knowledge, attitude and practices of dental practitioners regarding temporomandibular joint disorders in India. J Adv Clin Res Insights 2016;3:64-71.         [ Links ]

38. Lee WY, Choi JW, Lee JW. A study of dentists´ knowledge and beliefs regarding temporomandibular disorders in Korea. CRANIO 2000; 18:142-146.         [ Links ]

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