Palpation of the lateral pterygoid area in the myofascial pain diagnosis

Persistent myogenic temporomandibular disorders: Are navigation-guided botulinum toxin-A injections into the lateral pterygoid muscles effective?

BACKGROUND

Botulinum toxin has proven effective in treating persistent myogenous temporomandibular disorders (M-TMDs) unresponsive to conservative therapies. While the usual injection sites are the masseter and temporalis muscles, the deeper lateral pterygoid muscle (LPM) is often overlooked due to its difficulty of access and the risk of local complications. This study aims to evaluate the effectiveness of botulinum toxin-A injections (BTX-A) in the LPM with MR-guided navigation of patients with persistent M-TMDs.

METHODS

This retrospective study enrolled 34 patients suffering from M-TMDs despite conservative therapies with a total of 51 injection sessions. All of them were treated by BTX-A injections in the LPM using MR-guided navigation, masseter and temporalis with clinical guidance. The effectiveness of the treatment was evaluated with measures of maximum pain-intensity scores of breakthrough and background pain, maximal interincisal mouth opening (MIO), and the presence of joint sounds. The assessment was conducted before injections, and subsequently, at 1 and 3 months postoperatively. Adverse events and perception of improvement with the treatment were also reported for each injection sessions.

RESULTS

BTX-A injections in the LPM significantly improved pain scores intensity with a reduction of 65 % and 49 % respectively at the 1- and 3-month follow-ups, with peak effectiveness at 1 month. This study showed also a statistically significant improvement in mean MIO at 3 months post-injection and a decrease in joint sounds with persistence in 9,7 % of cases at 3-month follow-up compared to 41,2 % at baseline. No significant adverse events were observed. Patients treated with BTX-A injections in the LPM had a subjective complete improvement in their perception of treatment efficacy in 63 % of cases at the end of the follow-up period.

CONCLUSIONS

This study reports clinical experience on the use of MR-guided navigation to perform accurate, reliable, and safe BTX-A injections in the LPM. Although our results appear to be encouraging regarding symptom improvement of patients suffering from persistent M-TMDs, this approach may not be feasible as a primary standard procedure for managing M-TMDs. Further research is necessary to explore potential reproducible, safe, and cost-effective alternatives to enhance the accessibility of the LPM in clinical practice.

Anatomical consideration of ultrasonography-guided intraoral injection for temporal tendinitis

Temporal tendinitis is characterized by acute inflammation often resulting from mechanical stress, such as repetitive jaw movements associated with jaw opening and closing and teeth clenching. Treatment for temporal tendinitis typically involves the administration of local anesthetic or corticosteroid injections. However, the complex anatomical structure of the coronoid process, to which the temporalis tendon attaches, located deep within the zygomatic arch, poses challenges for accurate injections. In this study, we aimed to establish guidelines for the safe and effective treatment of temporal tendinitis by using intraoral ultrasonography (US) to identify the anatomical structures surrounding the temporalis tendon and coronoid process. US was performed using an intraoral transducer on 58 volunteers without temporomandibular joint disease. The procedure involved placing the transducer below the occlusal plane of the maxillary second molar. Measurements were taken for the horizontal distance from the anterior border of the coronoid process, observed at the midpoint (MP) of the US images, and the depth of the coronoid process and temporalis muscle from the oral mucosa. The anterior border of the coronoid process was visualized on all US images and classified into three observed patterns at the MP: type A (anterior to the MP, 56.2%), type B (at the MP, 16.1%), and type C (posterior to the MP, 27.7%). The temporalis muscle was located at a mean depth of 3.12 ± 0.68 mm from the oral mucosa. The maxillary second molar is an intraoral landmark for visualizing the anterior border of the coronoid process. The new location information obtained using intraoral US could help identify the safest and most effective injection sites for the treatment of temporal tendinitis.

Temporal tendinosis: A cause of chronic orofacial pain

PURPOSE OF REVIEW

Diverse musculoskeletal disorders and neuropathic symptoms of the face pose significant diagnostic challenges. In particular, temporal tendinosis is generally overlooked in the medical and dental literature and is therefore a poorly understood topic and often problematic cause of chronic orofacial pain. In this article, we explore temporal tendinosis as a cause of unresolved orofacial pain by reviewing the complex anatomy of the temporalis muscle, common presentations of temporal tendinosis, possible etiologies for injury and place a strong emphasis on required diagnostic evaluation and clinical management.

RECENT FINDINGS

Temporal tendinosis remains under diagnosed due to a combination of anatomical complexity and incomplete description in the majority of general anatomy medical textbooks. The two main presentations are unilateral facial pain with or without temporal headache and pain radiating from the distal temporalis tendon to the temporalis muscle. Diagnosis should be made with a combination of focused history, physical examination and specialised imaging, preferably with ultrasound but with MRI an alternate option. While many management options are available, optimal treatment remains unclear. Temporal tendinosis is an under-recognised and under-treated condition. Despite the fact that orofacial pain is one of the single most common complaints of patients presenting to physicians or dentists, it is widely acknowledged that training for diagnosis and manage of temporal tendinopathy among primary care physicians in both medical and dental professions is inadequate. This may result in extensive workups, leading to suboptimal management and chronic pain syndromes.

Ultrasound-Guided Injection of the Temporalis Tendon: A Novel Technique

A novel technique, ultrasound-guided injection of the temporalis tendon in adults, is described. Ultrasound-guided injection of the temporalis tendon is based on visualization of the temporalis muscle, temporalis tendon, and coronoid process. A practical step-by-step guide to doing the procedure is given. This technique is effective and reproducible. Two patients successfully treated with this technique will be briefly discussed. The anatomic location and size of the temporalis tendon make it mandatory to use ultrasound to ensure precision.

A critical overview of the current myofascial pain literature - September 2016

This edition of the overview of the current myofascial pain literature includes 24 studies, case reports and systematic and narrative reviews. Surprisingly, five of the 24 papers were difficult to read and interpret mostly because of a poor mastery of the English language. It is somewhat surprising that journal editors and reviewers would accept papers that are needlessly difficult to read and not direct the authors to language services or others who could improve the quality of the writings. Of course, it is exciting that researchers and clinicians from all over the world continue to focus on myofascial pain and attempt to shed new light on the complexity of the problem to improve the clinical decision-making process and eventually clinical approaches and outcomes. There were no new papers on manual therapies, but many focused on dry needling.

Executive summary of the Diagnostic Criteria for Temporomandibular Disorders for clinical and research applications

BACKGROUND

In this executive summary, the authors describe a protocol for assessing patients with temporomandibular disorder (TMD). It is based on the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) for clinical and research applications.

METHODS

The DC/TMD was developed using published Axis I physical diagnoses for the most common TMDs. Axis I diagnostic criteria were derived from pertinent clinical TMD signs and symptoms. Axis II consists of psychosocial and behavioral questionnaires already in the public domain. A panel of experts vetted and modified the Axis I and Axis II diagnostic protocols. Recommended changes were assessed for diagnostic accuracy by using the Validation Project's data set, which formed the basis for the development of the DC/TMD.

RESULTS

Axis I diagnostic criteria for TMD pain-related disorders have acceptable validity and provide definitive diagnoses for pain involving the temporomandibular joint (TMJ) and masticatory muscles. Axis I diagnostic criteria for the most common TMJ intra-articular disorders are appropriate for screening purposes only. A definitive diagnosis for TMJ intra-articular disorders requires computed tomography or magnetic resonance imaging. Axis II questionnaires provide valid assessment of psychosocial and behavioral factors that can affect management of TMD.

CONCLUSIONS

The DC/TMD provides a questionnaire for the pain history in conjunction with validated clinical examination criteria for diagnosing the most common TMDs. In addition, it provides Axis II questionnaires for assessing psychosocial and behavioral factors that may contribute to the onset and perpetuation of the patient's TMD.

PRACTICAL IMPLICATIONS

The DC/TMD is appropriate for use in clinical and research settings to allow for a comprehensive assessment of patients with TMD.

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†

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 self report 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.

Clinical assessment of patients with orofacial pain and temporomandibular disorders

Accurate diagnosis of chronic pain disorders of the mouth, jaws, and face is frequently complex. It is common for patients with chronic orofacial pain to consult multiple clinicians and receive ineffective treatment before a correct diagnosis is reached. This problem is a significant public health concern. Clinicians can minimize error by starting the diagnostic procedure with a careful, accurate history and thorough head and neck examination followed by a thoughtfully constructed differential diagnosis. The possibility that the patient has symptoms of a life-threatening underlying disease rather than a more common dental, sinus, or temporomandibular disorder must always be considered.

Diagnostic challenges of nonodontogenic toothache

The objective of this article was to present two nonodontogenic conditions that may mimic odontogenic toothache: trigeminal neuralgia and burning mouth syndrome. Two cases are presented in which one is related to the upper left second premolar and the other is related to the upper left first molar. Both showed pain when chewing. These two cases highlight the complexities involved in diagnosing nonodontogenic toothache. This article demonstrates the importance of having a thorough knowledge of both odontogenic and nonodontogenic toothache, as well as the need for careful evaluation of the nature of the pain and history, clinical and radiographic examinations.

Temporal tendinitis: a modified Levandoski panoramic analysis of 21 cases

In 1993, Levandoski published the details of a system to analyze panoramic radiographs and especially, the temporomandibular joints. Piedra expanded the work of Levandoski to analyze facial and dental asymmetries. In this brief treatise, the disorder of temporal tendinitis was explored. A modified Levandoski technique was used to compare the lengths of the coronoid and condylar processes in an attempt to demonstrate how the panoramic radiograph can be simply used in the diagnosis of temporal tendinitis in the retrospective study of 21 such cases.

CONCLUSIONS

a total of 18 of the 21 coronoid processes (85%) were equal to or longer than their condylar process counterparts, thus indicating that a panoramic radiograph may be useful in the diagnosis of temporal tendinitis.