Review articles
 

By Dr. Anna D'Urso , Dr. Emanuela Coppotelli , Dr. Doria Tolevski Meshkova , Dr. Silvia Del Prete
Corresponding Author Dr. Silvia Del Prete
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, Via Caserta 6 - Italy
Submitting Author Dr. Silvia Del Prete
Other Authors Dr. Anna D'Urso
Departement of Oral and Maxillofacial Sciences, Sapienza University of Rome, Italy - Italy

Dr. Emanuela Coppotelli
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, italy - Italy

Dr. Doria Tolevski Meshkova
Department of Oral and Maxillofacial Sciences, Sapienza University of Rome, italy - Italy

ORTHODONTICS

TMD, Fibromyalgia, ACR, DC/TMD, Functional Somatic Syndrome

D'Urso A, Coppotelli E, Tolevski Meshkova D, Del Prete S. Association between Temporomandibular Disorders and Fibromyalgia: A review. WebmedCentral ORTHODONTICS 2014;5(12):WMC004781
doi: 10.9754/journal.wmc.2014.004781

This is an open-access article distributed under the terms of the Creative Commons Attribution License(CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
No
Submitted on: 11 Dec 2014 09:50:57 PM GMT
Published on: 12 Dec 2014 09:40:17 AM GMT

Abstract


Fibromyalgia (FM) and Temporomandibular Disorders (TMD) are two different painful disorders whose clinical conditions often overlap. The presence of Fibromyalgia may represent a risk factor for the development of a temporomandibular disorder and worsen the prognosis. Several studies in the literature have highlighted common clinical symptoms and predisposing factors. However, the etiology of the two diseases have not been fully clarified yet in the literature. The purpose of the work is taking stock of the knowledge in the literature about the two diseases separately and their overlap and possible interaction.

 

 

Introduction


Fibromyalgia (FM) is defined by the American College of Rheumatology (ACR) as a disorder characterized by widespread pain and tenderness in at least 11 of 18 musculoskeletal sites for at least 3 months (1).

Temporomandibular Disorders (TMD) is a generic term that identifies a number of clinical problems that involve the masticatory musculature, the temporomandibular joint and associated structures (2)

TMD and FM are both musculoskeletal chronic pathologies. The pain due to Temporomandibular Disorders is localized, while the pain due to Fibromyalgia disease is diffuse and may involve different parts of the body. For this reason, it may be possible an overlap between FM and TMD (2).

Several studies in the past linked Fibromyalgia and Temporomandibular Disorders (3-8). In this studies Fibromyalgia was found to be very frequent in patients with TMD and vice versa. Fibromyalgia was considered a risk factor for the development of TMD (9).

Both of these diseases share common symptoms such as muscle pain, generalized pain sensitivity, fatigue, difficulty concentrating (10). In patients with fibromyalgia and temporomandibular disorders are also frequently found: state of anxiety, depression and reduced stress response (11, 12).

The casual relationship between these two multifactorial and non-specific disorders is not yet clarified and has opened a debate on the possibility of considering them as distinct clinical entity or not. The purpose of this article is to clarify the status of the literature on the subject, highlighting the aspects of each disease separately and then underlining the correlations

Temporomandibular Disorders (TMD)


Temporomandibular disorders include the collection of pathological condition of the temporomandibular joint, mastication muscles and associated structures (13). The complexity of the disease has led, in recent years, to consider TMD as multifactorial disorders, both for the frequent association of causal factors and for the current inability of researchers to recognize the true etiological factors.

Typical aspects of temporomandibular disorders, such as temporomandibular joint pain and functional limitation of mandibular movements, are frequently associated with painful symptoms including neck pain, headaches and brachialgia. Moreover, the presence of symptoms such as tinnitus and vertigo often put the patient with TMD in differential diagnosis with ENT pathology (14).

The literature shows that about 60%-70% of the population has or reports at least one sign of temporomandibular disorders, but only the 5% is under treatment for the disease (15). TMD are the second most common cause of facial pain, occurring mainly in young and middle-aged women (16). The chronic form of these pathological conditions represents a very negative development.

The treatment of the disorder involves multiple health care providers and are more complex and less auspicious prognosis (17). The increase in the population of this type of disease has a very high social cost (in the US was estimated at 4 million dollars) (18).

The most common worldwide used tool for the diagnosis of temporomandibular disorders is the Diagnostic Criteria (DC/TMD) System, updated in 2014; it represents a useful method in clinical practice for high reliability (19).

The new classification DC/TMD divides the DTM in 11 clinical forms, grouped in 2 categories:

  • Painful (pain disorders): arthralgia, myalgia (local myalgia, myofascial pain, myofascial pain reported), headache attributed to the TMD.
  • Articular (joint disorders): four disorders dislocation of the disc (the disc dislocation reduced, irreducible dislocation of the disc without limitation of mouth opening or limitation of mouth opening displacement and reduced with intermittent lock), degenerative diseases of ATM and subluxation.

Several studies have highlighted some predisposing factors for the development of TMD (20):

  • female gender
  • somatic symptoms and psychological effects (somatization. dissatisfaction with life, mental instability, depression)
  • vulnerability to musculoskeletal pain present throughout the body

The temporomandibular disorders fall within the Group of Regional Pain Syndrome (along with interstitial cystitis, irritable bowel syndrome, the vulvodinie, chronic pain in lower back) and often co-exist with common chronic algic diseases, such as fibromyalgia, in the wider family of central sensitization syndromes(21).

Fibromyalgia (FM)


Fibromyalgia is a syndrome characterized by chronic widespread, musculoskeletal pain, stiffness, not restored sleep, fatigue, cognitive dysfunction (known as the "fibro fog") and, consequently, impaired daily activities. The diagnostic feature is the presence of "tender points" in the muscle and connective tissue in all four quadrants of the body (22, 23).

The diagnosis is made using the Fibromyalgia Classification Criteria given by the American College of Rheumatology (ACR) in 1990 (1) (Figure 1). Although the ACR criteria are the standard criteria currently used to study FM, it is believed that fibromyalgia is not a musculoskeletal disorder; rather, it fits into a larger group of disorders that includes chronic widespread pain, diffuse tenderness, severity and discomfort (24-28).

Nel 1984 Yunus (29) included FM in the family of "Central Sensitization Syndromes", including a series of diseases with clinical and pathophysiological continuous and an overlap between phenotypic and nosographic expression.

Frequently in patients with fibromyalgia can be found other associated disorders such as temporomandibular disorders, primary headaches, interstitial cystitis, chronic pain, lower back pain, chronic fatigue syndrome, primary dysmenorrheal, psychiatric disorders such as anxiety and depression with painful physical symptoms and many other (29).

Fibromyalgia is part of a functional somatic syndrome that includes several related diseases characterized by more symptoms, suffering, disability and by objective structural/functional abnormalities. These syndromes include multiple chemical sensitivity, the sick building syndrome, repetitive strain injury (RSI), the side effects of silicone breast implants, the Gulf War syndrome, chronic whiplash injury, chronic fatigue syndrome (CFS), irritable bowel syndrome, and fibromyalgia (30).

The real etiology of fibromyalgia is still unknown. The most accredited hypothesis are:

  • central processing errors of sensory peripheral information (31)
  • Abnormalities in the hypothalamic-pituitary-adrenal axis have been identified (32)
  • An increase in the levels of substance P, serotonin, and growth hormone (33)

Predisposing factors seem to be:

  • Familiar
  • Physical trauma
  • Psychological trauma
  • Contracted infection as a child

In several studies the prevalence of fibromyalgia varies from a minimum of 4,7% to a maximum of 13,2%.  Female gender is affected about 1,5-2 times more than men (34).

Fibromyalgia is characterized by the following symptoms :

  • Widespread musculoskeletal pain and tender points
  • Sleep not restored
  • Morning stiffness
  • Fatigue
  • Headache
  • Irritable bowel syndrome
  • Temporomandibular disorders
  • Subjective numbness, swelling, tingling
  • Chest pain
  • Dizziness
  • Cognitive dysfunction, short-term memory loss
  • Restless legs
  • Mood disorders- anxiety, depression

The clinical aspects of this pathology significantly reduces the quality of life of subjects affected and it represent a social and economic cost for patients and their families.

Temporomandibular Disorders and Fibromyalgia


Several studies, in the past, have connected fibromyalgia and temporomandibular disorders (35-40). These studies have established the frequency with which the TMD were found in patients with fibromyalgia and vice versa.

In a large sample of patients affected by fibromyalgia the 94% reported TMD symptoms, including pain and difficulty in chewing and in mouth opening, which followed preexisting fibromyalgia long lasting pain (41).

Clinical studies revealed that the 68% to the 97% of fibromyalgia patients have TMD signs and symptoms(42-43).

Patients affected by fibromyalgia most frequently report TMD symptoms than vice versa (36). A study reported that the 75% of FM patients met the TMD criteria, whereas only 18% of TMD patients fulfilled the FM criteria.

Two prospective cohort studies, of both adults (44) and adolescents (45), found that the presence of multiple pain conditions, elsewhere in the body, could predict the onset of temporomandibular joint disorders pain within the next 3 years. It has been reported that widespread pain predicts the onset of dysfunctional temporomandibular joint disorders pain among women, but not its maintenance among either women or men(46).

However Rammelsberg et al. (47) observed that other body pains contributed to the persistence of masticatory myofascial pain.

Other studies showed that the presence of fibromyalgia can be an independent risk factor for the development of a myofascial TMD (48).

More recently it has been shown that a clinically manifest temporomandibular disorder occurs more frequently in patients already suffering from FM (49).

Fibromyalgia has been considered far more debilitating with respect to number of pain sites, somatic symptoms, and level of pain intensity than TMD.

FM patients report more functional disability, work difficulty, and overall health dissatisfaction. On the contrary, studies found that select clinical features, including muscle palpation and mouth opening did not differ between FM patients and those with masticatory myofascial pain syndrome (50). Other studies found that pain type, intensity, description, and quality were similar in both temporomandibular disorders and fibromyalgia patients (42).

Several general health problems have been reported to be equally frequent in FM and TMD patients, and they share common symptoms such as muscle pain, generalized pain sensitivity, sleep and concentration difficulties, bowel complaints, and headaches (51).

Depression and anxiety are also common in fibromyalgia as well as in temporomandibular disorders patients(43, 52).

Increased pain sensitivity was reported for both patient groups during functional dental investigation, stress and depression, as signs of somatization, were discussed as etiologic cofactors in TMD and FM (53-55). Thus, it has been suggested that temporomandibular disorders may be considered a stress-related disorder similar to fibromyalgia and chronic fatigue syndrome. Stress related disorders are characterized by common somatic and psychologic complaints such as fatigue, sleep disturbances, anxiety, and depression (51,56). In a study among patients with face painful fibromyalgia the 71% also had a TMD (57).

Some studies investigating pain sensitivity of TMD patients in extra-trigeminal regions reported increased experimentally evoked pain in non-facial areas (58,59), while others failed to detect this phenomenon (60). It was suggested that generalized up-regulation of Central Nervous System responsiveness to aversive stimulation may constitute a pathophysiologic mechanism contributing to myofascial pain in TMD patients(58).

Both temporomandibular disorders and fibromyalgia patients have demonstrated greater sensitivity to pain, hyperalgesia, lower pain thresholds in the cold and pressure pain (61). This could indicate temporomandibular disorders as a precursor of FMS in a continuous spectrum sharing the same underlying pathology. Central nervous system dysfunction and the resultant alteration in pain perception might be the cause for the TMD in FM patients (62).

Fantoni et al. (63) advocate the inclusion of TMD in the group of Functional Somatic Syndrome (comprising also fibromyalgia) due to the following evidence in literature: TMD share many symptoms with FSS, including chronic pain, headaches, dizziness, nausea, and unrefreshing sleep.  

Conclusions


Temporomandibular disorders and Fibromyalgia are closely related disorders that require a multidisciplinary approach. The aim is to prevent all those common risk factors and early interception in order to reduce disability and improve prognosis. It would be desirable the neurologist would send patients to visit gnathological specialist because of the high prevalence of fibromyalgia patients with temporomandibular disorders.

References


  1. Wolfe F, Smythe HA, Yunus MB, et al. The American College of Rheumatology 1990 Criteria for the Classification of Fibromyalgia. Report of the Multicenter Criteria Committee. Arthritis Rheum1990; 33:160-72.
  2. Okeson JP. Temporomandibular disorders: guidelines for evaluation, diagnosis, and management.Chicago:American Academy of Orofacial Pain; Quintessence Publishing; 1996.
  3. Hedenberg-Magnusson B, Ernberg M, Kopp S. Presence of orofacial pain and temporomandibular disorder in fibromyalgia. A study by questionnaire. Swed Dent J. 1999; 23:185-92.
  4. Plesh O, Wolfe F, Lane N. The relationship between fibromyalgia and temporomandibular disorders: prevalence and symptom severity. J Rheumatol. 1996; 23:1948-52.
  5. McCain GA, Scudds RA. The concept of primary fibromyalgia (fibrositis): clinical value, relation and significance to other chronic musculoskeletal pain syndromes. Pain. 1988; 33:273-87.
  6. Eriksson PO, Lindman R, Stal P, Bengtsson A. Symptoms and signs of mandibular dysfunction in primary fibromyalgia syndrome(PSF) patients. Swed Dent J. 1988; 12:141-9.
  7. Blasberg B, Chalmers A. Temporomandibular pain and dysfunction syndrome associated with generalized musculoskeletal pain: a retrospective study. J Rheumatol Suppl. 1989; 19:87-90.
  8. Fricton JR. The relationship of temporomandibular disorders and fibromyalgia: implications for diagnosis and treatment. Curr Pain Headache Rep. 2004; 8:355-63.
  9. Torsten J, Miglioretti DL, Leresche L, Von Korff M, Critchlow CW. Widespread pain as a risk factor for dysfunctional temporomandibular disorder pain. Pain. 2003; 102:257-263
  10. Aaron LA, Burke MM, Buchwald D. Overlapping conditions among patients with chronic fatigue syndrome, fibromyalgia, and temporomandibular disorder. Arch Intern Med. 2000; 160:221-7.
  11. Rhodus NL, Fricton J, Carlson P, Messner R. Oral symptoms associated with fibromyalgia syndrome. J Rheumatol. 2003; 30:1841-5.
  12. Hudson JI, Pope HG Jr. Fibromyalgia and psychopathology: is fibromyalgia a form of "affective spectrum disorder"? J Rheumatol Suppl. 1989; 19:15-22.
  13. Di Paolo C, Cascone P. Patologia dell'articolazione Temporomandibolare. UTET. 2004
  14. Molina OF, dos Santos J, Nelson SJ, Nowlin T. A clinical study of specific signs and symptoms of CMD in bruxers classified by the degree of severity. The Journal of Craniomandibular Practice, 1999; 17: 268-278.
  15. Dimitroulis G. Temporomandibular disorders: A clinical update. BMJ 1998; 317:190-4
  16. Kassler GD, Greene CS. The changing field of temporomandibular disorders: What dentists need to know. J Can Dent Assoc. 2009; 75:49- 53
  17. Von Korff M. Health services research and temporomandibular pain. In: Sessle BJ, Bryant PS, Dionne RA, eds. Temporomandibular disorders and related pain conditions. Seattle: IASP Press. 1995; 227-36.
  18. Gatchel RJ, Stowell AW, Wildenstein L, Riggs R, Ellis E 3rd Efficacy of an early intervention for    patients with acute temporomandibular disorders- related pain: a one year outcome study.JADA 2006; 137(3):339-47.
  19. Schiffman E, Ohrbach R, Truelove E, Look J, Anderson G, Goulet JP, et al. Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for Clinical and Research Applications: recommendations of the International RDC/TMD Consortium Network* and Orofacial Pain Special Interest Group†. J Oral Facial Pain Headache. 2014; 28(1):6-27.
  20. LeResche, L., Mancl, L., Drangsholt, M. T., Huang, G., & Von Korff, M. Predictors of onset of facial pain and temporomandibular disorders in early adolescence. Pain. 2007; 129, 269-278.
  21. Smith HS, Harris R, Clauw D. Fibromyalgia: an afferent processing disorder leading to a complex pain generalized syndrome. Pain Physician. 2011; 14(2):E217-45.
  22. Balasubramaniam R, Laudenbach JM, Stoopler ET. Fibromyalgia: An update for oral health care providers. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007; 104:589-602
  23. Aaron LA, Burke MM, Buchwald D. Overlapping conditions among patients with chronic fatigue syndrome, fibromyalgia and temporomandibular disorders. Arch Intern Med. 2000; 160:221-7.
  24. Wolfe F, Ross K, Anderson J, Russell IJ. Aspects of fibromyalgia in the general population: sex, pain threshold, and fibromyalgia symptoms. J Rheumatol. 1995; 22:151-6.
  25. Wolfe F, Anderson J, Harkness D, et al. Health status and disease severity in fibromyalgia: results of a six-center longitudinal study. Arthritis Rheum. 1997; 40:1571-9.
  26. Croft P. Testing for tenderness: what's the point? J Rheumatol. 2000; 27:2531-3.
  27. Croft P, Burt J, Schollum J, Thomas E, Macfarlane G, Silman A. More pain, more tender points: is fibromyalgia just one end of a continuous spectrum? Ann Rheum Dis. 1996; 55:482-5.
  28. Croft P, Schollum J, Silman A. Population study of tender point counts and pain as evidence of fibromyalgia. BMJ. 1994; 309:696-9.
  29. Yunus MB. Primary fibromyalgia syndrome: Current concepts. Compr Ther. 1984; 10:21-28.
  30. Barsky AJ, Borus JF. Functional somatic syndromes. Ann Intern Med. 1999; 130:910-21
  31. Smith HS, Harris R, Clauw D. Fibromyalgia: an afferent processing disorder leading to a complex pain generalized syndrome. Pain Physician. 2011; 14(2):E217-45.
  32. Gur A, Oktayoglu P. Central nervous system abnormalities in fibromyalgia and chronic fatigue syndrome: new concepts in treatment. Curr Pharm Des. 2008; 14:1274-94.
  33. Clauw DJ. Perspectives on fatigue from the study of chronic fatigue syndrome and related conditions. PMR. 2010; 2:414-30
  34. Jones GT1, Atzeni F, Beasley M, Flüß E, Sarzi-Puttini P, Macfarlane GJ. The prevalence of fibromyalgia in the general population - a comparison of the American College of Rheumatology 1990, 2010 and modified 2010 classification criteria. Arthritis Rheumatol. 2014 Oct 16. doi: 10.1002/art.38905. [Epub ahead of print]
  35. Hedenberg-Magnusson B, Ernberg M, Kopp S. Presence of orofacial pain and temporomandibular disorder in fibromyalgia. A study by questionnaire. Swed Dent J. 1999; 23:185-92.
  36. Plesh O, Wolfe F, Lane N. The relationship between fibromyalgia and temporomandibular disorders: prevalence and symptom severity. J Rheumatol. 1996; 23:1948-52.
  37. McCain GA, Scudds RA. The concept of primary fibromyalgia (fibrositis): clinical value, relation and significance to other chronic musculoskeletal pain syndromes. Pain. 1988; 33:273-87.
  38. Eriksson PO, Lindman R, Stal P, Bengtsson A. Symptoms and signs of mandibular dysfunction in primary fibromyalgia syndrome (PSF) patients. Swed Dent J. 1988; 12:141-9.
  39. Blasberg B, Chalmers A. Temporomandibular pain and dysfunction syndrome associated with generalized musculoskeletal pain: a retrospective study. J Rheumatol Suppl. 1989; 19:87-90.
  40. Fricton JR. The relationship of temporomandibular disorders and fibromyalgia: implications for diagnosis and treatment. Curr Pain Headache Rep. 2004; 8:355-63.
  41. Wolfe F, Ross K, Anderson J, Russell IJ, Hebert L. The prevalence and characteristics of fibromyalgia in the general population. Arthritis Rheum. 1995; 38:19-28.
  42. Pennacchio EA, Borg-Stein J, Keith DA. The incidence of pain in the muscles of mastication in patients with fibromyalgia. J Mass Dent Soc. 1998; 47:8-12.
  43. Rhodus NL, Fricton J, Carlson P, Messner R. Oral symptoms associated with fibromyalgia syndrome. J Rheumatol. 2003; 30:1841-5.
  44. Von Korff M, LeResche L, Dworkin SF. First onset of common pain symptoms: A prospective study of depression as a risk factor. Pain. 1993; 55:251-258.
  45. LeResche L, Mancl LA, Drangsholt MT, Huang G, Von Korff M. Predictors of onset of facial pain and temporomandibular disorders in early adolescence. Pain. 2007; 129:269-278.
  46. John MT, Miglioretti DL, LeResche L, Von Korff M, Critchlow CW. Widespread pain as a risk factor for dysfunctional temporomandibular disorder pain. Pain. 2003; 102:257-263.
  47. Rammelsberg P, Le Resche L, Dworkin S, Mancl L. Longitudinal outcome of temporomandibular disorders: A 5-year epidemiologic study of muscle disorders defined by research diagnostic criteria for temporomandibular disorders. J Orofac Pain. 2003; 17:9-20.
  48. Torsten J, Miglioretti DL, Leresche L, Von Korff M, Critchlow CW.  Widespread pain as a risk factor for dysfunctional temporomandibular disorder pain. Pain. 2003; 102:257-263
  49. Velly AM, Look JO, Schiffman E, Lenton PA, Kang W, Messner RP, Holcroft CA, Fricton JR.The effect of fibromyalgia and widespread pain on the clinically significant temporomandibular muscle and joint pain disorders: a prospective 18-month cohort study. J Pain. 2010; 11:1155-1164
  50. Cimino R, Michelotti A, Stradi R, Farinaro C. Comparison of clinical and psychologic features of fibromyalgia and masticatory myofascial pain. J Orofac Pain. 1998; 12:35-41.
  51. Aaron LA, Burke MM, Buchwald D. Overlapping conditions among patients with chronic fatigue syndrome, fibromyalgia, and temporomandibular disorder. Arch Intern Med. 2000; 160:221-7.
  52. Hudson JI, Pope HG Jr. Fibromyalgia and psychopathology: is fibromyalgia a form of"affective spectrum disorder"? J Rheumatol Suppl. 1989; 19:15-22.
  53. Aggarwal VR, McBeth J, Zakrzewska JM, Lunt M, Macfarlane GJ. Are reports of mechanical dysfunction in chronic oro-facial pain related to somatisation? A population based study. Eur J Pain.2008; 12:501-7.
  54. Sieber M, Grubenmann E, Ruggia GM, Palla S. Relation between stress and symptoms of craniomandibular disorders in adolescents. Schweiz Monatsschr Zahnmed. 2003; 113:648-54.
  55. Van Houdenhove B, Egle UT. Fibromyalgia: a stress disorder? Piecing the biopsychosocial puzzle together. Psychother Psychosom. 2004; 73: 267-75.
  56. Korszun A, Papadopoulos E, Demitrack M, Engleberg C, Crofford L. The relationship between temporomandibular disorders and stress-associate syndromes. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 1998; 86:416-20.
  57. Ramesh Balasubramaniam, BDSc,a Reny de Leeuw, DDS et al. Prevalence of temporomandibular disorders in fibromyalgia and failed back syndrome patients: A blinded prospective comparison study Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007; 104:204-16
  58. Sarlani E, Grace EG, Reynolds MA, Greenspan JD. Evidence for up-regulated central nociceptive processing in patients with masticatory myofascial pain. J Orofac Pain. 2004; 18:41-55.
  59. Svensson P, List T, Hector G. Analysis of stimulus-evoked pain in patients with myofascial temporomandibular pain disorders. Pain. 2001; 92:399-409.
  60. Carlson CR, Reid KI, Curran SL, Studts J, Okeson JP, Falace D, Nitz A, Bertrand PM.Psychological and physiological parameters of masticatory muscle pain. Pain. 1998; 76:297-307.
  61. Pfau DB, Rolke R, Nickel R, Treede Rolf-Detlef, Daublaender M. Somatosensory profiles in subgroups of patients with myogenic temporomandibular disorders and fibromyalgia syndrome Pain.2009; 147:72-83
  62. Balasubramaniam R, Laudenbach JM, Stoopler ET. Fibromyalgia: An update for oral health care providers. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2007; 104:589-602. 
  63. Fantoni F, Salvetti G, Manfredini D, Bosco M. Current concepts on functional somatic syndromes and    temporomandibular disorders. Stomatologija. 2007; 9:3-9

Source(s) of Funding


None

Competing Interests


None

Reviews
0 reviews posted so far

Comments
0 comments posted so far

Please use this functionality to flag objectionable, inappropriate, inaccurate, and offensive content to WebmedCentral Team and the authors.

 

Author Comments
0 comments posted so far

 

What is article Popularity?

Article popularity is calculated by considering the scores: age of the article
Popularity = (P - 1) / (T + 2)^1.5
Where
P : points is the sum of individual scores, which includes article Views, Downloads, Reviews, Comments and their weightage

Scores   Weightage
Views Points X 1
Download Points X 2
Comment Points X 5
Review Points X 10
Points= sum(Views Points + Download Points + Comment Points + Review Points)
T : time since submission in hours.
P is subtracted by 1 to negate submitter's vote.
Age factor is (time since submission in hours plus two) to the power of 1.5.factor.

How Article Quality Works?

For each article Authors/Readers, Reviewers and WMC Editors can review/rate the articles. These ratings are used to determine Feedback Scores.

In most cases, article receive ratings in the range of 0 to 10. We calculate average of all the ratings and consider it as article quality.

Quality=Average(Authors/Readers Ratings + Reviewers Ratings + WMC Editor Ratings)