M.H. Steenks

Masticatory function in subacute TMD patients before and after treatment

Masticatory function can be impaired in temporomandibular disorders (TMDs) patients. We investigated whether treatment of subacute non-specific TMD patients may influence oral function and clinical outcome measures. Fifteen patients with subacute TMD participated in the study. We quantified masticatory performance, maximum voluntary bite force, muscle activity and chewing cycle duration before and after treatment. Masticatory performance and bite force of patients were compared with the results obtained for an age- and gender-matched group of subjects without TMD complaints. Furthermore, we determined possible changes in anamnestic and clinical scores from questionnaires (mandibular function impairment questionnaire; MFIQ), pain scores and clinical outcome measures. Maximum bite force significantly increased, although the values after treatment were still significantly lower than those of the subjects without TMD complaints. The corresponding electromyography values did not show significant change after treatment. The masticatory performance of the patients remained unaltered; patients chewed significantly less efficient than controls. The average duration of chewing cycles significantly decreased after treatment. We observed a significant improvement in MFIQ scores. During the clenching and chewing tasks, the visual analogue scale scores were significantly higher than before these tasks. We may conclude that subacute temporomandibular joint disorders negatively influence chewing behaviour. Bite force, chewing cycle duration and also perceived mandibular function significantly improved after treatment, although the masticatory performance remained unaltered.

Dysphagia in spinal muscular atrophy type II More than a bulbar problem

Objective: In patients with spinal muscular atrophy (SMA) type II, feeding problems and dysphagia are common, but the underlying mechanisms of these problems are not well defined. This case control study was designed to determine the underlying mechanisms of dysphagia in SMA type II. Methods: Six children with SMA type II and 6 healthy matched controls between 6.4 and 13.4 years of age were investigated during swallowing liquid and solid food in 2 different postures using surface EMG (sEMG) of the submental muscle group (SMG) and a video fluoroscopic swallow study (VFSS). Results: The VFSS showed postswallow residue of solid food in the vallecula and above the upper esophageal sphincter (UES), which can be responsible for indirect aspiration. Better results in swallowing were achieved in a more forward head position. These findings were supported by the sEMG measurements of the SMG during swallowing. Conclusions: Dysphagia in spinal muscular atrophy type II is due to a neurologic dysfunction (lower motor neuron problems from the cranial nerves in the brainstem) influencing the muscle force and efficiency of movement of the tongue and the submental muscle group in combination with a biomechanical component (compensatory head posture). The results suggest an integrated treatment with an adapted posture during meals and the advice of drinking water after meals to prevent aspiration pneumonias.

Reduced mandibular range of motion in Duchenne Muscular Dystrophy: predictive factors.

Patients with Duchenne muscular dystrophy (DMD) experience negative effects upon feeding and oral health. We aimed to determine whether the mandibular range of motion in DMD is impaired and to explore predictive factors for the active maximum mouth opening (aMMO). 23 patients with DMD (mean age 16.7 ± 7.7 years) and 23 controls were assessed using a questionnaire about mandibular function and impairments. All participants underwent a clinical examination of the masticatory system, including measurement of mandibular range of motion and variables related to mandibular movements. In all patients, quantitative ultrasound of the digastric muscle and the geniohyoid muscle and the motor function measure (MFM) scale were performed. The patients were divided into early and late ambulatory stage (AS), early non-ambulatory stage (ENAS) and late non-ambulatory stage (LNAS). All mandibular movements were reduced in the patient group (P < 0.001) compared to the controls. Reduction in the aMMO (<40 mm) was found in 26% of the total patient group. LNAS patients had significantly smaller mandibular movements compared to AS and ENAS (P < 0.05). Multiple linear regression analysis for aMMO revealed a positive correlation with the body height and disease progression, with MFM total score as the strongest independent risk factor (R(2) = 0.71). Mandibular movements in DMD are significantly reduced and become more hampered with loss of motor function, including the sitting position, arm function, and neck and head control. We suggest that measurement of the aMMO becomes a part of routine care of patients with DMD.

Reliability and Validity of the Diagnostic Criteria for Temporomandibular Disorders Axis I in Clinical and Research Settings: A Critical Appraisal

The recently published Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) Axis I, which is recommended for use in clinical and research settings, has provided an update of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). The authors of the DC/TMD based their publication on the results of a Validation Project (2001-2008) and consecutive workgroup sessions held between 2008 and 2013. The DC/TMD represents a major change in both content and procedures; nonetheless, earlier concerns and new insights have only partly been followed up when drafting the new recommendations. Moreover, the emphasis on immediate implementation in clinical and research settings is not in line with the provided external evidence on which the DC/TMD is based. This Focus Article describes these concerns with regard to several aspects of the DC/TMD: the additional classification categories; the high dependency on pressure-pain results from use of the recommended palpation technique; the TMD pain screening instrument; the test population characteristics; the utility of additional subgroups; the use of a reference standard; the dichotomy between pain and dysfunction; and the DC/TMD algorithms. Thus, although the DC/TMD represents an improvement over the RDC/TMD, its immediate implementation in research and clinical care does not yet appear to be adequately substantiated.

Authors' Response to Critical Commentaries: Reliability and Validity of the DC/TMD Axis I

No abstract available.