Comparison of international classification of orofacial pain (icop) and diagnostic criteria for temporomandibular disorders (dc/tmd) algorithms for diagnosing myofascial orofacial pain

The International Classification of Orofacial Pain (ICOP) is a new classification system for orofacial pains, which was published in February 2020. However, this clinical diagnostic criteria has not been validated or tested to be reliable for diagnosing myofascial orofacial pain (MOP). This study aimed to determine whether the ICOP diagnostic algorithm can effectively identify MOP when compared with the gold standard, Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) algorithm. This retrospective cross-sectional study constructed the diagnostic algorithm from the ICOP and the DC/TMD criteria. The clinical data of MOP patients was extracted from clinical charts in the Occlusion and Orofacial Pain Clinic, Chulalongkorn University, Thailand. Two independent clinicians in TMD and Orofacial Pain postgraduate program and three undergraduate dental students identified the MOP subgroups based on ICOP and DC/TMD algorithms. Overall, 119 DC/TMD myalgia datasets were screened and all cases were classified into subgroups of MOP according to ICOP algorithm. Despite the limitations associated with the retrospective design, the sensitivity of the ICOP algorithm for identifying MOP was equal to 1 when compared to DC/TMD algorithm. The sensitivity value for identifying “local myalgia” and “myofascial pain with referral” based on ICOP algorithms were equal to 1. The inter-rater reliability for executing ICOP algorithm were consistent among undergraduate students; 95% confidence interval [0.862, 1.000], and postgraduate dentists; 95% confidence interval [0.900, 1.000]. In summary, this study indicates that the sensitivity of the ICOP algorithm was comparable to the DC/TMD algorithm for correctly identifying MOP.