Difference between revisions of "Orofacial Pain"

[[File:Question 2.jpg|200x200px|link=https://wiki.masticationpedia.org/index.php/File:Question_2.jpg|left]]The text provides a comprehensive discussion on the complexities of diagnosing and managing orofacial pain and temporomandibular disorders (TMD), intertwining various scientific concepts and models to better understand these conditions. It starts with an introduction to orofacial pain, specifically focusing on pain management for temporomandibular sensitization and the common coexistence of orofacial pain with headaches and neck pain. These relationships suggest mutual influences and potentially shared pathophysiological mechanisms.

A significant portion of the discussion is dedicated to the correlation between TMD and other disorders like headaches, emphasizing the need to consider a broader range of pathologies when evaluating symptoms that may initially appear related to TMD. This section highlights the complex interplay between these conditions, where each may exacerbate the other, pointing towards a holistic approach to diagnosis and treatment.

The narrative then shifts towards a more theoretical discussion on statistical methodologies used in the study of TMD, comparing Bayesian and frequentist statistics. This comparison underscores the nuances of each approach, particularly focusing on the flexibility and interpretive benefits of Bayesian statistics which may offer more nuanced insights into the relationships between symptoms and underlying disorders.

In addition to theoretical discussions, practical aspects such as the International Classification of Headache Disorders and the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) are mentioned, providing a framework for understanding the diagnostic criteria and classification used in practice.

As usual in the presentation of new sections of specific chapters, it is advisable to introduce recent and documented references on the subject which in this case is 'Orofacial Pain' and Temporomandibular Disorders. In this sense we can partially report a brief introduction by Martina Ferrillo et al.<ref>Martina Ferrillo, Amerigo Giudice, Nicola Marotta, Francesco Fortunato,Daniela Di Venere,Antonio Ammendolia, Pietro Fiore, and  Alessandro de Sire. Pain Management and Rehabilitation for Central Sensitization in Temporomandibular Disorders: A Comprehensive Review. Int J Mol Sci. 2022 Oct; 23(20): 12164. Published online 2022 Oct 12. doi: 10.3390/ijms232012164. PMCID: PMC9602546. PMID: 36293017</ref> on which we will make the first conceptual reflections reported by our thoughtful Linus before proceeding to the presentation of the clinical cases.

The author points out that orofacial and neck pain comorbidities are often associated with TMD.<ref>Plesh O., Adams S.H., Gansky S.A. Temporomandibular joint and muscle disorder-type pain and comorbid pains in a national US sample. J. Orofac. Pain. 2011;25:190–198.</ref> These coexisting conditions (particularly headaches, migraines, and neck pain) are not only highly associated with chronic pain-related TMDs, but also increase the risk of their development.<ref>Bender S.D. Orofacial pain and headache: A review and look at the commonalities. Curr Pain Headache Rep. 2014;18:400. doi: 10.1007/s11916-013-0400-5.</ref><ref name=":0">Botros J., Gornitsky M., Samim F., der Khatchadourian Z., Velly A.M. Back and neck pain: A comparison between acute and chronic pain-related Temporomandibular Disorders. Can. J. Pain. 2022;6:112–120. doi: 10.1080/24740527.2022.2067032. </ref><ref>Ohrbach R., Fillingim R.B., Mulkey F., Gonzalez Y., Gordon S., Gremillion H., Lim P.-F., Ribeiro-Dasilva M., Greenspan J.D., Knott C. Clinical findings and pain symptoms as potential risk factors for chronic tmd: Descriptive data and empirically identified domains from the opera case-control study. J. Pain. 2011;12:T27–T45. doi: 10.1016/j.jpain.2011.09.001</ref> The International Classification of Headaches (ICHD)<ref>Headache Classification Committee of the International Headache Society (IHS) The International Classification of Headache Disorders; 3rd edition (beta version) Cephalalgia. 2013;33:629–808. doi: 10.1177/0333102413485658.</ref> and DC/TMD<ref name=":4">Schiffman E., Ohrbach R., Truelove E., Look J., Anderson G., Goulet J.P., List T., Svensson P., Gonzalez Y., Lobbezoo F., 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;28:6–27. doi: 10.11607/jop.1151</ref> consider the main characteristics of pain in headache and TMD, respectively. There are several hypotheses that attempt to explain the association between TMD and headache, including neuronal convergence, central sensitization, and inhibition of descending pain downregulatory mechanisms.<ref name=":1">Matre D., Knardahl S. ‘Central sensitization’ in chronic neck/shoulder pain. Scand. J. Pain. 2012;3:230–235. doi: 10.1016/j.sjpain.2012.04.003. </ref><ref name=":2">Su M., Yu S. Chronic migraine: A process of dysmodulation and sensitization. Mol. Pain. 2018;14:1744806918767697. doi: 10.1177/1744806918767697.</ref> The close relationship between TMD, headache and neck pain has recently been evaluated, not only in terms of sharing common pathogenetic mechanisms and clinical features, but also considering that one condition might influence or promote the development of another.<ref>Chaves T.C., Dach F., Florencio L.L., Carvalho G.F., Gonçalves M.C., Bigal M.E., Speciali J.G., Bevilaqua-Grossi D. Concomitant Migraine and Temporomandibular Disorders are Associated With Higher Heat Pain Hyperalgesia and Cephalic Cutaneous Allodynia. Clin. J. Pain. 2016;32:882–888. doi: 10.1097/AJP.0000000000000369.</ref><ref name=":0" /><ref>Gonçalves D.A., Camparis C.M., Speciali J.G., Franco A.L., Castanharo S.M., Bigal M.E. Temporomandibular disorders are differentially associated with headache diagnoses: A controlled study. Clin. J. Pain. 2011;27:611–615. doi: 10.1097/AJP.0b013e31820e12f5.</ref> These conditions can cause facial pain and are frequently associated with the development of craniofacial allodynia during painful exacerbation.<ref name=":3">Greenspan J.D., Slade G.D., Bair E., Dubner R., Fillingim R.B., Ohrbach R., Knott C., Diatchenko L., Liu Q., Maixner W. Pain sensitivity and autonomic factors associated with development of TMD: The OPPERA prospective cohort study. J. Pain. 2013;14:T63–T74.e746. doi: 10.1016/j.jpain.2013.06.007.</ref> Indeed, pain in both conditions has been attributed to common dysfunctions of central pain regulation mechanisms..<ref>Furquim B.D., Flamengui L.M., Conti P.C. TMD and chronic pain: A current view. Dental Press J. Orthod. 2015;20:127–133. doi: 10.1590/2176-9451.20.1.127-133.sar.</ref><ref>Bevilaqua-Grossi D., Lipton R.B., Napchan U., Grosberg B., Ashina S., Bigal M.E. Temporomandibular disorders and cutaneous allodynia are associated in individuals with migraine. Cephalalgia. 2010;30:425–432. doi: 10.1111/j.1468-2982.2009.01928.x.</ref> On the other hand, the concomitant TMD and migraine showed worse levels of cutaneous hyperalgesia and allodynia, probably due to central and peripheral nervous system sensitization and impairment of descending pain modulatory pathways.<ref>Conti P.C., Costa Y.M., Gonçalves D.A., Svensson P. Headaches and myofascial temporomandibular disorders: Overlapping entities, separate managements? J. Oral Rehabil. 2016;43:702–715. doi: 10.1111/joor.12410.</ref><ref>Furquim B.D., Flamengui L.M., Conti P.C. TMD and chronic pain: A current view. Dental Press J. Orthod. 2015;20:127–133. doi: 10.1590/2176-9451.20.1.127-133.sar.</ref>