R. Ohrbach | SUNY: University at Buffalo (original) (raw)

Papers by R. Ohrbach

Research paper thumbnail of The Effect of 2 Sympatholytic Medications—Propranolol and Clonidine— On Sleep Bruxism: Experimental Randomized Controlled Studies

Yearbook of Dentistry, 2007

Research paper thumbnail of Masticatory Muscle Duty Factors in TMD Diagnostic Groups

Objective: To test the hypothesis that during the day and night, masticatory muscle activities is... more Objective: To test the hypothesis that during the day and night, masticatory muscle activities is greater in individuals with temporomandibular disorders. Method: MRI and Research Diagnostic Criteria were used to categorize 71 informed and consenting subjects according to TMJ disc position (+DD = disc displacement) and pain status (+P = presence of pain). Male (n= 28) and female (n=42) subjects (+DD/+Pain, n=18; +DD/-Pain, n =14; -DD/-Pain, n=38) participated in two laboratory EMG/bite-force calibrations to determine subject-specific masseter and temporalis muscle threshold activities per 20 N bite-force (RMS20N, µV). Over 3 days subjects recorded day and night masseter and temporalis muscle activities using portable EMG recorders. Masseter and temporalis Duty Factors (DF = duration of muscle activity/total recording time, %) were determined based on muscle-specific thresholds of magnitude (5% to 80% RMS20N). ANOVA and Tukey-Kramer post-hoc tests were used to determine independent v...

Research paper thumbnail of Masticatory Muscle Electromyography during Biting in Humans with/without TMDs

Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) co... more Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) compared to healthy subjects (Iwasaki et al. 2009) and for increased muscle forces during jaw loading. Thus, this pilot study tested if individuals with/without temporomandibular disorders (TMDs) use their masticatory muscles similarly during molar biting. Methods: Subjects recruited gave informed consent to participate in IRB-approved protocols. Calibrated examiners used Research Diagnostic Criteria and TMJ magnetic resonance images to classify 71 subjects based on presence (+) or absence (-) of DD and pain into 3 groups (n=females,males): +DD/+pain (n=14,4), +DD/-pain (n=10,4), -DD/-pain (n=19,20). At each of 2 sessions, subjects performed standardized static and dynamic molar bites, 25 right and 25 left, on a calibrated transducer while bite-forces and surface electromyography from right masseter and anterior temporalis muscles were recorded. Slopes of electromyography (μV) versus bite-...

Research paper thumbnail of Masticatory Muscle Orientation Effects on Predicted Lateral Pterygoid Muscle Forces

Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD di... more Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD diagnostic group differences in lateral pterygoid muscle forces during static biting (Kohlmeier et al., 2012, J Dent Res, 91(SI A):578). Method: Research Diagnostic Criteria and magnetic resonance TMJ images were used by calibrated examiners to classify 93 subjects into 4 diagnostic groups based on presence(+) or absence (-) of disc displacement(DD) and pain [group, n=females, males: -DD/-pain, n=15, 13; -DD/+pain, n=8, 8; +DD/-pain, n=16, 13; +DD/+pain, n=15, 13). Subjects gave informed consent to participate in IRB-approved protocols. Three-dimensional geometries described positions of masticatory muscles, dental arches, and mandibular condyles for all subjects from lateral and posteroanterior cephalometric radiographs. The range of anteroposterior variations of masticatory muscle orientations represented (>1300 possible combinations) were used in 2 numerical models to identify key co...

Research paper thumbnail of TMD Diagnostic Group Differences in TMJ Disc Mechanics

Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects... more Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects of normal (perpendicular) load. Method: In accordance with IRB oversight, fifty-two subjects (30 female; 22 male) participated. Research Diagnostic Criteria-calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17; -DD/-Pain, n=17). 3-D craniomandibular geometries were produced for each subject and used in validated numerical models to calculate normal TMJ loads during biting on canine teeth. To test load effects on TMJ disc mechanics, ex vivo data were used in the development and validation of a biphasic finite element model (bFEM) of the TMJ disc. Given the scarcity of mechanical data from healthy human tissue, 187 freshly extracted pig TMJ discs were subjected to a 7.6 N static normal load, followed by cyclic movement. Physical data in the form of aspect ratio and velocity of stress-field translation, compressive...

Research paper thumbnail of Research Diagnostic Criteria for Temporomandibular Disorders: current status & future relevance1

Journal of Oral Rehabilitation, 2010

The Research Diagnostic Criteria for Temporomandibular Disorders (RDC ⁄ TMD), published in 1992, ... more The Research Diagnostic Criteria for Temporomandibular Disorders (RDC ⁄ TMD), published in 1992, was based on international expert recommendations and available empirical data. The major rationale was to offer a putative diagnostic and classification system whose reliability, validity and clinical usefulness for TMD diagnosis and classification could be scientifically evaluated and then revised using an evidence-based model for successive iterations. The present journal issue attests to the accomplishment of that major objective: the RDC ⁄ TMD has been translated into 18 languages and used very extensively in international research. One important component of that research has been to yield reliable and valid data resulting in an evidence-based revision of the RDC ⁄ TMD now available for continuing research and clinical application. The present article offers recommendations and speculations regarding how the RDC ⁄ TMD may continue to serve the function of guiding future research and, most importantly, serve as an evidence-based diagnostic and classification system to aid in the rational choice of clinical care for TMD sufferers around the world. Temporomandibular Disorders (RDC ⁄ TMD) Consortium sponsored Workshop devoted to 'Validation Studies of the RDC ⁄ TMD: Progress toward Version 2' and the future of the RDC ⁄ TMD is in my view, nothing less than an historical occasion in the history of clinical orofacial pain research and dental research more generally. I am most privileged to be asked to review the current status and future relevance of the RDC ⁄ TMD from the perspective of one who was involved in the initiation of both the RDC ⁄ TMD and the consortium.

Research paper thumbnail of Research Diagnostic Criteria for Temporomandibular Disorders: current status & future relevance1

Journal of Oral Rehabilitation, 2010

AIMS To estimate the criterion validity of the Research Diagnostic Criteria for Temporomandibular... more AIMS To estimate the criterion validity of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I TMD diagnoses. METHODS A combined total of 614 TMD community and clinic cases and 91 controls were examined at 3 study ...

Research paper thumbnail of Prevalence of Temporomandibular Pain and Subsequent Dental Treatment in Swedish Adolescents

Yearbook of Dentistry, 2006

Research paper thumbnail of The dilemma of scientific knowledge versus clinical management of temporomandibular disorders

The Journal of Prosthetic Dentistry, 1992

The dilemma of scientific knowledge versus clinical management of TMD is discussed by focus on fi... more The dilemma of scientific knowledge versus clinical management of TMD is discussed by focus on five questions; (1) What is scientific evidence and how is it transmitted? (2) What important evidence is lacking in the field of TMD? (3) What clinical concepts have been challenged by the scientific evidence? (4) Why is there adherence to concepts that appear to conflict with the evidence? (5) How does the clinician provide patient care in the face of uncertainty while retaining scientific integrity? It is concluded that no fundamental reason for a dilemma between scientific evidence and clinical practice need exist provided that (1) clinical investigators use appropriate research protocols and report results in refereed scientific journals and (2) dentists are familiar with the requirements of sound scientific evidence, interpret this evidence and its clinical implications, and apply it to the care of TMD patients.

Research paper thumbnail of Candidate genes associated with psychological risk factors for chronic pain – preliminary findings from the multisite OPPERA cohort study

The Journal of Pain, 2009

Research paper thumbnail of JOR-CORE recommendations on rehabilitation of temporomandibular disorders

Journal of Oral Rehabilitation, 2010

Research paper thumbnail of Sleep Apnea Symptoms and Risk of Temporomandibular Disorder: OPPERA Cohort

Journal of Dental Research, 2013

ABSTRACT The authors tested the hypothesis that obstructive sleep apnea (OSA) signs/symptoms are ... more ABSTRACT The authors tested the hypothesis that obstructive sleep apnea (OSA) signs/symptoms are associated with the occurrence of temporomandibular disorder (TMD), using the OPPERA prospective cohort study of adults aged 18 to 44 years at enrollment (n = 2,604) and the OPPERA case-control study of chronic TMD (n = 1,716). In both the OPPERA cohort and case-control studies, TMD was examiner determined according to established research diagnostic criteria. People were considered to have high likelihood of OSA if they reported a history of sleep apnea or ≥ 2 hallmarks of OSA: loud snoring, daytime sleepiness, witnessed apnea, and hypertension. Cox proportional hazards regression estimated hazard ratios (HRs) and 95% confidence limits (CL) for first-onset TMD. Logistic regression estimated odds ratios (OR) and 95% CL for chronic TMD. In the cohort, 248 individuals developed first-onset TMD during the median 2.8-year follow-up. High likelihood of OSA was associated with greater incidence of first-onset TMD (adjusted HR = 1.73; 95% CL, 1.14, 2.62). In the case-control study, high likelihood of OSA was associated with higher odds of chronic TMD (adjusted OR = 3.63; 95% CL, 2.03, 6.52). Both studies supported a significant association of OSA symptoms and TMD, with prospective cohort evidence finding that OSA symptoms preceded first-onset TMD.

Research paper thumbnail of Intersection of Temporalis Myofascial Pain with Tension-Type Headache Diagnoses

Research paper thumbnail of Diagnostic validity of current and revised RDC/TMD for myofascial pain diagnoses

Research paper thumbnail of Assessment and further development of RDC/TMD Axis II biobehavioural instruments: a research programme progress report

Journal of Oral Rehabilitation, 2010

A symposium was held in Toronto, 2008, in which research progress regarding the biobehavioural di... more A symposium was held in Toronto, 2008, in which research progress regarding the biobehavioural dimension of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) was presented. An extended workshop was held in April 2009 in which further recommendations were made from an expert panel, using the 2008 symposium material as a base. This paper is a summary of the 2008 symposium proceedings with elaborations based on further developments. Seven studies were conducted between 2001 and 2008, in which the following were investigated: (i) basic properties of Axis II instruments, (ii) reliability and criterion validity of Axis II instruments, (iii) expansion of predictors, (iv) metric equivalence of the depression and non-specific physical symptoms subscales in the RDC/TMD, (v) laboratory investigation of oral behaviours, (vi) field data collection of oral behaviours, and (vii) functional limitation of the jaw. Methods and results for each of these studies are described. Based on the results of these studies that have been published, as well as the direction of interim results from the few studies that await completion and publication, the biobehavioural domain of the RDC/TMD, as published in 1992, is reliable and valid. These results also provide strong evidence supporting the future growth of the biobehavioural domain as the RDC/TMD matures into subsequent protocols for both clinical and research applications.

Research paper thumbnail of 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†

Journal of Oral & Facial Pain and Headache, 2014

Aims: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I ... more Aims: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥ 0.95. Consequently, these empirical results supported the development of revised RDC/TMD Axis I diagnostic algorithms that were subsequently demonstrated to be valid for the most common pain-related TMD and for one temporomandibular joint (TMJ) intra-articular disorder. The original RDC/TMD Axis II instruments were shown to be both reliable and valid. Working from these findings and revisions, two international consensus workshops were convened, from which recommendations were obtained for the finalization of new Axis I diagnostic algorithms and new Axis II instruments. Methods: Through a series of workshops and symposia, a panel of clinical and basic science pain experts modified the revised RDC/TMD Axis I algorithms by using comprehensive searches of published TMD diagnostic literature followed by review and consensus via a formal structured process. The panel's recommendations for further revision of the Axis I diagnostic algorithms were assessed for validity by using the Validation Project's data set, and for reliability by using newly collected data from the ongoing TMJ Impact Project-the follow-up study to the Validation Project. New Axis II instruments were identified through a comprehensive search of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. Results: The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting any pain-related TMD as well as valid diagnostic criteria for differentiating the most common pain-related TMD (sensitivity ≥ 0.86, specificity ≥ 0.98) and for one intra-articular disorder (sensitivity of 0.80 and specificity of 0.97). Diagnostic criteria for other common intra-articular disorders lack adequate validity for clinical diagnoses but can be used for screening purposes. Inter-examiner reliability for the clinical assessment associated with the validated DC/TMD criteria for pain-related TMD is excellent (kappa ≥ 0.85). Finally, a comprehensive classification system that includes both the common and less common TMD is also presented. The Axis II protocol retains selected original RDC/TMD screening instruments augmented with new instruments to assess jaw function as well as behavioral and additional psychosocial factors. The Axis II protocol is divided into screening and comprehensive selfreport instrument sets. The screening instruments' 41 questions assess pain intensity, pain-related disability, psychological distress, jaw functional limitations, and parafunctional behaviors, and a pain drawing is used to assess locations of pain. The comprehensive instruments, composed of 81 questions, assess in further detail jaw functional limitations and psychological distress as well as additional constructs of anxiety and presence of comorbid pain conditions. Conclusion: The recommended evidence-based new DC/TMD protocol is appropriate for use in both clinical and research settings. More comprehensive instruments augment short and simple screening instruments for Axis I and Axis II. These validated instruments allow for identification of patients with a range of simple to complex TMD presentations.

Research paper thumbnail of Expanding the taxonomy of the diagnostic criteria for temporomandibular disorders

Journal of Oral Rehabilitation, 2014

There is a need to expand the current temporomandibular disorders' (TMDs) classification to inclu... more There is a need to expand the current temporomandibular disorders' (TMDs) classification to include less common but clinically important disorders. The immediate aim was to develop a consensus-based classification system and associated diagnostic criteria that have clinical and research utility for less common TMDs. The long-term aim was to establish a foundation, vis-a-vis this classification system, that will stimulate data collection, validity testing and further criteria refinement. A working group [members of the International RDC/TMD Consortium Network of the International Association for Dental Research (IADR), members of the Orofacial Pain Special Interest Group (SIG) of the International Association for the Study of Pain (IASP), and members from other professional societies] reviewed disorders for inclusion based on clinical significance, the availability of plausible diagnostic criteria and the ability to operationalise and study the criteria. The disorders were derived from the literature when possible and based on expert opinion as necessary. The expanded TMDs taxonomy was presented for feedback at international meetings. Of 56 disorders considered, 37 were included in the expanded taxonomy and were placed into the following four categories: temporomandibular joint disorders, masticatory muscle disorders, headache disorders and disorders affecting associated structures. Those excluded were extremely uncommon, lacking operationalised diagnostic criteria, not clearly related to TMDs, or not sufficiently distinct from disorders already included within the taxonomy. The expanded TMDs taxonomy offers an integrated approach to clinical diagnosis and provides a framework for further research to operationalise and test the proposed taxonomy and diagnostic criteria.

Research paper thumbnail of Summary of Findings From the OPPERA Prospective Cohort Study of Incidence of First-Onset Temporomandibular Disorder: Implications and Future Directions

The Journal of Pain, 2013

Papers in this issue investigate when and how putative risk factors influence development of firs... more Papers in this issue investigate when and how putative risk factors influence development of first-onset, painful temporomandibular disorder (TMD). The results represent first findings from the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) prospective cohort study that monitored 2,737 men and women aged 18 to 44 years recruited at 4 U.S. study sites. During a median 2.8-year follow-up period, 260 participants developed TMD. The average incidence rate of 4% per annum was influenced by a broad range of phenotypic risk factors including sociodemographic characteristics, health status, clinical orofacial factors, psychological functioning, pain sensitivity, and cardiac autonomic responses. A novel method of multivariable analysis used random forest models to simultaneously evaluate contributions of all 202 phenotypic variables. Variables from the health status domain made the greatest contribution to TMD incidence, followed closely by psychological and clinical orofacial domains. However, only a few measures of pain sensitivity and autonomic function contributed to TMD incidence, and their effects were modest. Meanwhile, age and study site were independent predictors of TMD incidence, even after controlling for other phenotypes. Separate analysis of 358 genes that regulate pain found several novel genetic associations with intermediate phenotypes that, themselves, are risk factors for TMD, suggesting new avenues to investigate biological pathways contributing to TMD. Collectively, the papers in this issue demonstrate that TMD is a complex disorder with multiple causes consistent with a biopsychosocial model of illness. It is a misnomer and no longer appropriate to regard TMD solely as a localized orofacial pain condition.

Research paper thumbnail of Recommendations from the International Consensus Workshop: convergence on an orofacial pain taxonomy

Journal of Oral Rehabilitation, 2010

disciplines included radiology, psychology, ontology, and patient advocacy. The workshop members ... more disciplines included radiology, psychology, ontology, and patient advocacy. The workshop members were divided into workgroups that reviewed core literature describing the properties of the RDC ⁄ TMD, provided recommendations for revision, and suggested relevant research directions. The goals of this workshop were to (i) finalize the revision of the RDC ⁄ TMD into a Diagnostic Criteria for Temporomandibular Disorders (DC ⁄ TMD), which would be more appropriate for routine clinical implementation, (ii) provide a broad foundation for the further development of suitable diagnostic systems for not only TMD but also oro-facial pain as well, and (iii) provide research recommendations oriented towards improving our understanding of TMD and oro-facial pain. This report provides the full description of the workshop and Executive Summary, and it acknowledges the participants and sponsors.

Research paper thumbnail of Reliability of electromyographic activity vs. bite-force from human masticatory muscles

European Journal of Oral Sciences, 2011

The reproducibility of electromyographic (EMG) activity in relation to static bite-force from mas... more The reproducibility of electromyographic (EMG) activity in relation to static bite-force from masticatory muscles for a given biting situation is largely unknown. Our aim was to evaluate the reliability of EMG activity in relation to static bite-force in humans. Eighty-four subjects produced 5 unilateral static bites of different forces at different biting positions on molars and incisors, at two separate sessions, while surface EMG activities were recorded from temporalis, masseter, and suprahyoid muscles bilaterally. Intraclass Correlation Coefficients (ICCs) were used, where an ICC of ≥ 0.60 indicated good reliability of these slopes. ICCs for jaw closing muscles during molar biting were: temporalis ipsilateral 0.58 to 0.93 and contralateral 0.88 to 0.91, masseter ipsilateral 0.75 to 0.86 and contralateral 0.69 to 0.88; while during incisor biting were: temporalis ipsilateral 0.56 to 0.81 and contralateral 0.34 to 0.86, masseter ipsilateral 0.65 to 0.78 and contralateral 0.59 to 0.80. For the suprahyoid muscles the confidence intervals were mostly wide and most included zero. Slopes of the EMG activity versus bite-force for a given biting situation were reliable for temporalis and masseter muscles. These results support the use of these outcome measurements for the estimation and validation of mechanical models of the masticatory system.

Research paper thumbnail of The Effect of 2 Sympatholytic Medications—Propranolol and Clonidine— On Sleep Bruxism: Experimental Randomized Controlled Studies

Yearbook of Dentistry, 2007

Research paper thumbnail of Masticatory Muscle Duty Factors in TMD Diagnostic Groups

Objective: To test the hypothesis that during the day and night, masticatory muscle activities is... more Objective: To test the hypothesis that during the day and night, masticatory muscle activities is greater in individuals with temporomandibular disorders. Method: MRI and Research Diagnostic Criteria were used to categorize 71 informed and consenting subjects according to TMJ disc position (+DD = disc displacement) and pain status (+P = presence of pain). Male (n= 28) and female (n=42) subjects (+DD/+Pain, n=18; +DD/-Pain, n =14; -DD/-Pain, n=38) participated in two laboratory EMG/bite-force calibrations to determine subject-specific masseter and temporalis muscle threshold activities per 20 N bite-force (RMS20N, µV). Over 3 days subjects recorded day and night masseter and temporalis muscle activities using portable EMG recorders. Masseter and temporalis Duty Factors (DF = duration of muscle activity/total recording time, %) were determined based on muscle-specific thresholds of magnitude (5% to 80% RMS20N). ANOVA and Tukey-Kramer post-hoc tests were used to determine independent v...

Research paper thumbnail of Masticatory Muscle Electromyography during Biting in Humans with/without TMDs

Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) co... more Objective: Numerical modeling predicts higher TMJ forces for those with disc displacement (DD) compared to healthy subjects (Iwasaki et al. 2009) and for increased muscle forces during jaw loading. Thus, this pilot study tested if individuals with/without temporomandibular disorders (TMDs) use their masticatory muscles similarly during molar biting. Methods: Subjects recruited gave informed consent to participate in IRB-approved protocols. Calibrated examiners used Research Diagnostic Criteria and TMJ magnetic resonance images to classify 71 subjects based on presence (+) or absence (-) of DD and pain into 3 groups (n=females,males): +DD/+pain (n=14,4), +DD/-pain (n=10,4), -DD/-pain (n=19,20). At each of 2 sessions, subjects performed standardized static and dynamic molar bites, 25 right and 25 left, on a calibrated transducer while bite-forces and surface electromyography from right masseter and anterior temporalis muscles were recorded. Slopes of electromyography (μV) versus bite-...

Research paper thumbnail of Masticatory Muscle Orientation Effects on Predicted Lateral Pterygoid Muscle Forces

Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD di... more Objective: It is unknown if variations in masticatory muscle orientation explain predicted TMD diagnostic group differences in lateral pterygoid muscle forces during static biting (Kohlmeier et al., 2012, J Dent Res, 91(SI A):578). Method: Research Diagnostic Criteria and magnetic resonance TMJ images were used by calibrated examiners to classify 93 subjects into 4 diagnostic groups based on presence(+) or absence (-) of disc displacement(DD) and pain [group, n=females, males: -DD/-pain, n=15, 13; -DD/+pain, n=8, 8; +DD/-pain, n=16, 13; +DD/+pain, n=15, 13). Subjects gave informed consent to participate in IRB-approved protocols. Three-dimensional geometries described positions of masticatory muscles, dental arches, and mandibular condyles for all subjects from lateral and posteroanterior cephalometric radiographs. The range of anteroposterior variations of masticatory muscle orientations represented (>1300 possible combinations) were used in 2 numerical models to identify key co...

Research paper thumbnail of TMD Diagnostic Group Differences in TMJ Disc Mechanics

Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects... more Objective: To determine TMD diagnostic group differences in TMJ disc mechanics due to the effects of normal (perpendicular) load. Method: In accordance with IRB oversight, fifty-two subjects (30 female; 22 male) participated. Research Diagnostic Criteria-calibrated investigators classified subjects based on signs of disc displacement (DD) and pain (+DD/+Pain, n=18; +DD/-Pain, n=17; -DD/-Pain, n=17). 3-D craniomandibular geometries were produced for each subject and used in validated numerical models to calculate normal TMJ loads during biting on canine teeth. To test load effects on TMJ disc mechanics, ex vivo data were used in the development and validation of a biphasic finite element model (bFEM) of the TMJ disc. Given the scarcity of mechanical data from healthy human tissue, 187 freshly extracted pig TMJ discs were subjected to a 7.6 N static normal load, followed by cyclic movement. Physical data in the form of aspect ratio and velocity of stress-field translation, compressive...

Research paper thumbnail of Research Diagnostic Criteria for Temporomandibular Disorders: current status & future relevance1

Journal of Oral Rehabilitation, 2010

The Research Diagnostic Criteria for Temporomandibular Disorders (RDC ⁄ TMD), published in 1992, ... more The Research Diagnostic Criteria for Temporomandibular Disorders (RDC ⁄ TMD), published in 1992, was based on international expert recommendations and available empirical data. The major rationale was to offer a putative diagnostic and classification system whose reliability, validity and clinical usefulness for TMD diagnosis and classification could be scientifically evaluated and then revised using an evidence-based model for successive iterations. The present journal issue attests to the accomplishment of that major objective: the RDC ⁄ TMD has been translated into 18 languages and used very extensively in international research. One important component of that research has been to yield reliable and valid data resulting in an evidence-based revision of the RDC ⁄ TMD now available for continuing research and clinical application. The present article offers recommendations and speculations regarding how the RDC ⁄ TMD may continue to serve the function of guiding future research and, most importantly, serve as an evidence-based diagnostic and classification system to aid in the rational choice of clinical care for TMD sufferers around the world. Temporomandibular Disorders (RDC ⁄ TMD) Consortium sponsored Workshop devoted to 'Validation Studies of the RDC ⁄ TMD: Progress toward Version 2' and the future of the RDC ⁄ TMD is in my view, nothing less than an historical occasion in the history of clinical orofacial pain research and dental research more generally. I am most privileged to be asked to review the current status and future relevance of the RDC ⁄ TMD from the perspective of one who was involved in the initiation of both the RDC ⁄ TMD and the consortium.

Research paper thumbnail of Research Diagnostic Criteria for Temporomandibular Disorders: current status & future relevance1

Journal of Oral Rehabilitation, 2010

AIMS To estimate the criterion validity of the Research Diagnostic Criteria for Temporomandibular... more AIMS To estimate the criterion validity of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I TMD diagnoses. METHODS A combined total of 614 TMD community and clinic cases and 91 controls were examined at 3 study ...

Research paper thumbnail of Prevalence of Temporomandibular Pain and Subsequent Dental Treatment in Swedish Adolescents

Yearbook of Dentistry, 2006

Research paper thumbnail of The dilemma of scientific knowledge versus clinical management of temporomandibular disorders

The Journal of Prosthetic Dentistry, 1992

The dilemma of scientific knowledge versus clinical management of TMD is discussed by focus on fi... more The dilemma of scientific knowledge versus clinical management of TMD is discussed by focus on five questions; (1) What is scientific evidence and how is it transmitted? (2) What important evidence is lacking in the field of TMD? (3) What clinical concepts have been challenged by the scientific evidence? (4) Why is there adherence to concepts that appear to conflict with the evidence? (5) How does the clinician provide patient care in the face of uncertainty while retaining scientific integrity? It is concluded that no fundamental reason for a dilemma between scientific evidence and clinical practice need exist provided that (1) clinical investigators use appropriate research protocols and report results in refereed scientific journals and (2) dentists are familiar with the requirements of sound scientific evidence, interpret this evidence and its clinical implications, and apply it to the care of TMD patients.

Research paper thumbnail of Candidate genes associated with psychological risk factors for chronic pain – preliminary findings from the multisite OPPERA cohort study

The Journal of Pain, 2009

Research paper thumbnail of JOR-CORE recommendations on rehabilitation of temporomandibular disorders

Journal of Oral Rehabilitation, 2010

Research paper thumbnail of Sleep Apnea Symptoms and Risk of Temporomandibular Disorder: OPPERA Cohort

Journal of Dental Research, 2013

ABSTRACT The authors tested the hypothesis that obstructive sleep apnea (OSA) signs/symptoms are ... more ABSTRACT The authors tested the hypothesis that obstructive sleep apnea (OSA) signs/symptoms are associated with the occurrence of temporomandibular disorder (TMD), using the OPPERA prospective cohort study of adults aged 18 to 44 years at enrollment (n = 2,604) and the OPPERA case-control study of chronic TMD (n = 1,716). In both the OPPERA cohort and case-control studies, TMD was examiner determined according to established research diagnostic criteria. People were considered to have high likelihood of OSA if they reported a history of sleep apnea or ≥ 2 hallmarks of OSA: loud snoring, daytime sleepiness, witnessed apnea, and hypertension. Cox proportional hazards regression estimated hazard ratios (HRs) and 95% confidence limits (CL) for first-onset TMD. Logistic regression estimated odds ratios (OR) and 95% CL for chronic TMD. In the cohort, 248 individuals developed first-onset TMD during the median 2.8-year follow-up. High likelihood of OSA was associated with greater incidence of first-onset TMD (adjusted HR = 1.73; 95% CL, 1.14, 2.62). In the case-control study, high likelihood of OSA was associated with higher odds of chronic TMD (adjusted OR = 3.63; 95% CL, 2.03, 6.52). Both studies supported a significant association of OSA symptoms and TMD, with prospective cohort evidence finding that OSA symptoms preceded first-onset TMD.

Research paper thumbnail of Intersection of Temporalis Myofascial Pain with Tension-Type Headache Diagnoses

Research paper thumbnail of Diagnostic validity of current and revised RDC/TMD for myofascial pain diagnoses

Research paper thumbnail of Assessment and further development of RDC/TMD Axis II biobehavioural instruments: a research programme progress report

Journal of Oral Rehabilitation, 2010

A symposium was held in Toronto, 2008, in which research progress regarding the biobehavioural di... more A symposium was held in Toronto, 2008, in which research progress regarding the biobehavioural dimension of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) was presented. An extended workshop was held in April 2009 in which further recommendations were made from an expert panel, using the 2008 symposium material as a base. This paper is a summary of the 2008 symposium proceedings with elaborations based on further developments. Seven studies were conducted between 2001 and 2008, in which the following were investigated: (i) basic properties of Axis II instruments, (ii) reliability and criterion validity of Axis II instruments, (iii) expansion of predictors, (iv) metric equivalence of the depression and non-specific physical symptoms subscales in the RDC/TMD, (v) laboratory investigation of oral behaviours, (vi) field data collection of oral behaviours, and (vii) functional limitation of the jaw. Methods and results for each of these studies are described. Based on the results of these studies that have been published, as well as the direction of interim results from the few studies that await completion and publication, the biobehavioural domain of the RDC/TMD, as published in 1992, is reliable and valid. These results also provide strong evidence supporting the future growth of the biobehavioural domain as the RDC/TMD matures into subsequent protocols for both clinical and research applications.

Research paper thumbnail of 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†

Journal of Oral & Facial Pain and Headache, 2014

Aims: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I ... more Aims: The original Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) Axis I diagnostic algorithms have been demonstrated to be reliable. However, the Validation Project determined that the RDC/TMD Axis I validity was below the target sensitivity of ≥ 0.70 and specificity of ≥ 0.95. Consequently, these empirical results supported the development of revised RDC/TMD Axis I diagnostic algorithms that were subsequently demonstrated to be valid for the most common pain-related TMD and for one temporomandibular joint (TMJ) intra-articular disorder. The original RDC/TMD Axis II instruments were shown to be both reliable and valid. Working from these findings and revisions, two international consensus workshops were convened, from which recommendations were obtained for the finalization of new Axis I diagnostic algorithms and new Axis II instruments. Methods: Through a series of workshops and symposia, a panel of clinical and basic science pain experts modified the revised RDC/TMD Axis I algorithms by using comprehensive searches of published TMD diagnostic literature followed by review and consensus via a formal structured process. The panel's recommendations for further revision of the Axis I diagnostic algorithms were assessed for validity by using the Validation Project's data set, and for reliability by using newly collected data from the ongoing TMJ Impact Project-the follow-up study to the Validation Project. New Axis II instruments were identified through a comprehensive search of the literature providing valid instruments that, relative to the RDC/TMD, are shorter in length, are available in the public domain, and currently are being used in medical settings. Results: The newly recommended Diagnostic Criteria for TMD (DC/TMD) Axis I protocol includes both a valid screener for detecting any pain-related TMD as well as valid diagnostic criteria for differentiating the most common pain-related TMD (sensitivity ≥ 0.86, specificity ≥ 0.98) and for one intra-articular disorder (sensitivity of 0.80 and specificity of 0.97). Diagnostic criteria for other common intra-articular disorders lack adequate validity for clinical diagnoses but can be used for screening purposes. Inter-examiner reliability for the clinical assessment associated with the validated DC/TMD criteria for pain-related TMD is excellent (kappa ≥ 0.85). Finally, a comprehensive classification system that includes both the common and less common TMD is also presented. The Axis II protocol retains selected original RDC/TMD screening instruments augmented with new instruments to assess jaw function as well as behavioral and additional psychosocial factors. The Axis II protocol is divided into screening and comprehensive selfreport instrument sets. The screening instruments' 41 questions assess pain intensity, pain-related disability, psychological distress, jaw functional limitations, and parafunctional behaviors, and a pain drawing is used to assess locations of pain. The comprehensive instruments, composed of 81 questions, assess in further detail jaw functional limitations and psychological distress as well as additional constructs of anxiety and presence of comorbid pain conditions. Conclusion: The recommended evidence-based new DC/TMD protocol is appropriate for use in both clinical and research settings. More comprehensive instruments augment short and simple screening instruments for Axis I and Axis II. These validated instruments allow for identification of patients with a range of simple to complex TMD presentations.

Research paper thumbnail of Expanding the taxonomy of the diagnostic criteria for temporomandibular disorders

Journal of Oral Rehabilitation, 2014

There is a need to expand the current temporomandibular disorders' (TMDs) classification to inclu... more There is a need to expand the current temporomandibular disorders' (TMDs) classification to include less common but clinically important disorders. The immediate aim was to develop a consensus-based classification system and associated diagnostic criteria that have clinical and research utility for less common TMDs. The long-term aim was to establish a foundation, vis-a-vis this classification system, that will stimulate data collection, validity testing and further criteria refinement. A working group [members of the International RDC/TMD Consortium Network of the International Association for Dental Research (IADR), members of the Orofacial Pain Special Interest Group (SIG) of the International Association for the Study of Pain (IASP), and members from other professional societies] reviewed disorders for inclusion based on clinical significance, the availability of plausible diagnostic criteria and the ability to operationalise and study the criteria. The disorders were derived from the literature when possible and based on expert opinion as necessary. The expanded TMDs taxonomy was presented for feedback at international meetings. Of 56 disorders considered, 37 were included in the expanded taxonomy and were placed into the following four categories: temporomandibular joint disorders, masticatory muscle disorders, headache disorders and disorders affecting associated structures. Those excluded were extremely uncommon, lacking operationalised diagnostic criteria, not clearly related to TMDs, or not sufficiently distinct from disorders already included within the taxonomy. The expanded TMDs taxonomy offers an integrated approach to clinical diagnosis and provides a framework for further research to operationalise and test the proposed taxonomy and diagnostic criteria.

Research paper thumbnail of Summary of Findings From the OPPERA Prospective Cohort Study of Incidence of First-Onset Temporomandibular Disorder: Implications and Future Directions

The Journal of Pain, 2013

Papers in this issue investigate when and how putative risk factors influence development of firs... more Papers in this issue investigate when and how putative risk factors influence development of first-onset, painful temporomandibular disorder (TMD). The results represent first findings from the Orofacial Pain: Prospective Evaluation and Risk Assessment (OPPERA) prospective cohort study that monitored 2,737 men and women aged 18 to 44 years recruited at 4 U.S. study sites. During a median 2.8-year follow-up period, 260 participants developed TMD. The average incidence rate of 4% per annum was influenced by a broad range of phenotypic risk factors including sociodemographic characteristics, health status, clinical orofacial factors, psychological functioning, pain sensitivity, and cardiac autonomic responses. A novel method of multivariable analysis used random forest models to simultaneously evaluate contributions of all 202 phenotypic variables. Variables from the health status domain made the greatest contribution to TMD incidence, followed closely by psychological and clinical orofacial domains. However, only a few measures of pain sensitivity and autonomic function contributed to TMD incidence, and their effects were modest. Meanwhile, age and study site were independent predictors of TMD incidence, even after controlling for other phenotypes. Separate analysis of 358 genes that regulate pain found several novel genetic associations with intermediate phenotypes that, themselves, are risk factors for TMD, suggesting new avenues to investigate biological pathways contributing to TMD. Collectively, the papers in this issue demonstrate that TMD is a complex disorder with multiple causes consistent with a biopsychosocial model of illness. It is a misnomer and no longer appropriate to regard TMD solely as a localized orofacial pain condition.

Research paper thumbnail of Recommendations from the International Consensus Workshop: convergence on an orofacial pain taxonomy

Journal of Oral Rehabilitation, 2010

disciplines included radiology, psychology, ontology, and patient advocacy. The workshop members ... more disciplines included radiology, psychology, ontology, and patient advocacy. The workshop members were divided into workgroups that reviewed core literature describing the properties of the RDC ⁄ TMD, provided recommendations for revision, and suggested relevant research directions. The goals of this workshop were to (i) finalize the revision of the RDC ⁄ TMD into a Diagnostic Criteria for Temporomandibular Disorders (DC ⁄ TMD), which would be more appropriate for routine clinical implementation, (ii) provide a broad foundation for the further development of suitable diagnostic systems for not only TMD but also oro-facial pain as well, and (iii) provide research recommendations oriented towards improving our understanding of TMD and oro-facial pain. This report provides the full description of the workshop and Executive Summary, and it acknowledges the participants and sponsors.

Research paper thumbnail of Reliability of electromyographic activity vs. bite-force from human masticatory muscles

European Journal of Oral Sciences, 2011

The reproducibility of electromyographic (EMG) activity in relation to static bite-force from mas... more The reproducibility of electromyographic (EMG) activity in relation to static bite-force from masticatory muscles for a given biting situation is largely unknown. Our aim was to evaluate the reliability of EMG activity in relation to static bite-force in humans. Eighty-four subjects produced 5 unilateral static bites of different forces at different biting positions on molars and incisors, at two separate sessions, while surface EMG activities were recorded from temporalis, masseter, and suprahyoid muscles bilaterally. Intraclass Correlation Coefficients (ICCs) were used, where an ICC of ≥ 0.60 indicated good reliability of these slopes. ICCs for jaw closing muscles during molar biting were: temporalis ipsilateral 0.58 to 0.93 and contralateral 0.88 to 0.91, masseter ipsilateral 0.75 to 0.86 and contralateral 0.69 to 0.88; while during incisor biting were: temporalis ipsilateral 0.56 to 0.81 and contralateral 0.34 to 0.86, masseter ipsilateral 0.65 to 0.78 and contralateral 0.59 to 0.80. For the suprahyoid muscles the confidence intervals were mostly wide and most included zero. Slopes of the EMG activity versus bite-force for a given biting situation were reliable for temporalis and masseter muscles. These results support the use of these outcome measurements for the estimation and validation of mechanical models of the masticatory system.