Mechanism, Prevention, and Treatment of Radiation-Induced Salivary Gland Injury Related to Oxidative Stress

Radiation therapy is a common treatment for head and neck cancers. However, because of the presence of nerve structures (brain stem, spinal cord, and brachial plexus), salivary glands (SGs), mucous membranes, and swallowing muscles in the head and neck regions, radiotherapy inevitably causes damage to these normal tissues. Among them, SG injury is a serious adverse event, and its clinical manifestations include changes in taste, difficulty chewing and swallowing, oral infections, and dental caries. These clinical symptoms seriously reduce a patient’s quality of life. Therefore, it is important to clarify the mechanism of SG injury caused by radiotherapy. Although the mechanism of radiation-induced SG injury has not yet been determined, recent studies have shown that the mechanisms of calcium signaling, microvascular injury, cellular senescence, and apoptosis are closely related to oxidative stress. In this article, we review the mechanism by which radiotherapy causes oxidative stress and damages the SGs. In addition, we discuss effective methods to prevent and treat radiation-induced SG damage.

Tongue stretching: technique and clinical proposal

Objectives The tongue is an organ with multiple functions, from sucking to phonation, from swallowing to postural control and equilibrium. An incorrect position or mechanics of the tongue can causes sucking problems in the newborn or atypical swallowing in the adult, with repercussions on the position of the head and neck, up to influencing upright posture and other problems. Tongue dysfunctions are quite frequent (10–15%) in the population. For the manual therapist, this frequency indicates one to two subjects every 30 patients. Exercises have been proposed to improve the tone and strength of the swallowing muscles but the results are not so clear in the literature. The aim of this study is to describe and provide a tongue muscle normalization technique that helps the manual therapist in the treatment of problems related to it. Methods The literature has been investigated through pubmed, Google scholar of the last 10 years, the keywords used and combined with the Boolean operators AND and OR, are: “tongue, tongue habits, tongue diseases, taste disorder, neck pain, posture, postural balance, atypical swallowing, muscle stretching exercise, tissue expansion, soft tissue therapy, osteopathic manipulative treatment”. Results and Conclusions The technique is possible to be executed even in a sitting position, in the case the patient is unable to assume a supine position, the subject should provides immediate feedback that allows the therapist to understand if the technique has been correctly executed. The simplicity of execution and application of the technique makes it a possible and immediate therapeutic tool in the clinical setting.

Comparison of three different types of exercises for selective contractions of supra- and infrahyoid muscles

Several exercise methods, such as the Shaker exercise, tongue press exercise, chin tuck against resistance (CTAR) exercise, and submandibular push exercise, have been introduced to strengthen the muscles involved in swallowing. In this study, we compared the effectiveness of the CTAR, submandibular push, and Shaker exercises for the induction of selective supra- and infrahyoid muscle contractions using surface electromyography (EMG). This study is a prospective non-randomized controlled study. Twenty-five healthy subjects and 20 patients experiencing swallowing difficulty were enrolled. During the three different types of exercises, the root mean square (RMS) values of the sternocleidomastoid (SCM), suprahyoid (anterior belly of the digastric and mylohyoid muscles), and infrahyoid (sternothyroid and thyrohyoid muscles) muscles were analyzed using surface EMG. Differences in the activity of swallowing muscles among the three different exercises were analyzed using one-way repeated measured analysis of variance. In terms of both the maximum and mean RMS values of the suprahyoid muscle, the submandibular push exercise showed a larger RMS value than the CTAR and Shaker exercises in healthy subjects (p < 0.05). In terms of both the maximum and mean RMS values of the suprahyoid muscle, the Shaker exercise and submandibular push exercise showed a larger RMS value than the CTAR exercise in patients with swallowing difficulty (p < 0.05). The submandibular push exercise may be effective as a swallowing muscle exercise owing to its superiority in inducing selective contractions of the supra- and infrahyoid muscles. The CTAR and Shaker exercises are also effective in this regard.

DYSPHAGIA IN FIBROMYALGIA SYNDROME IN WOMEN: TRUTH OR MYTH? A CASE CONTROL STUDY

Purpose: This study was aimed to investigate the presence of dysphagia with multidimensional objective tests in FM female patients with and without dysphagia symptom compared to healthy female subjects. Methods: A case control study was conducted on 165 subjects (21 FM patients with dysphagia symptom, 62 FM patients without dysphagia symptom and 82 healthy subjects). All subjects were evaluated with a clinical screening test, endoscopy, electrophysiology of swallowing (dysphagia limit and swallowing intervals) and musculoskeletal ultrasound (cross-sectional thickness and area of swallowing muscles). Patients (with and without dysphagia symptom) and healthy subjects were compared in terms of all evaluation parameters. Results: The mean age of 165 subjects was [Formula: see text] years and all subjects ([Formula: see text], 100%) were female. Endoscopic evaluation results were similar among three groups ([Formula: see text]). Both the functional evaluation of swallowing measured by swallowing intervals ([Formula: see text]-value between 0.001 and 0.004) and the structural features assessed by the ultrasound ([Formula: see text]-value between 0.001 and 0.007) were significantly impaired in patient groups compared to healthy subjects. FM patients without dysphagia symptom also had significant impairments in function ([Formula: see text]-value between 0.001 and 0.004 for swallowing intervals) and structural features ([Formula: see text]-value between 0.001 and 0.007 for cross-sectional thickness and area of swallowing muscles) compared to healthy subjects. Conclusion: The structure and function of swallowing may be affected in patients with FM, even without dysphagia symptoms.

Dental, Occlusal, and Craniofacial Features of Children With Microcephaly Due to Congenital Zika Infection: 3 Cases Report From Valle del Cauca, Cali—Colombia—2020

Objective: Describes dental, occlusal, and craniofacial characteristics of 3 children aged 3 to 4 years with microcephaly due to congenital Zika infection in Cali Valle del Cauca, 2020. Design: Three children case report with congenital Zika virus microcephaly. Setting: Institutional Patients: Three children with maternal viral infection confirmed by polymerase chain reaction during first trimester of pregnancy were included and were born from 2016 to 2017. Interventions: Oral and mouth functional examination was performed including soft tissue examination; lingual and labial frenulum; evaluation of swallowing and chewing; craniofacial analysis; dimension of dental arch; intercanine and intermolar distance, palate form; relationship and growth of maxilla, mandible, and facial dental midline using plaster models; and complementary image analysis. Main Outcome Measures: Child and mother sociodemographic features, craniofacial measurements; dental and oral features; maxillary and mandibular measures; and speech, swallowing, and chewing disorders. Results: Small head circumference at birth and at the time of clinical evaluation was compared to normal children of approximately their age. Upper third of the face was short, and presence of hypertonic masticatory muscles with hypotonic swallowing muscles, dysphagia, dyslalia, bruxism, lip incompetence, tongue interposition, and hypersalivation and epilepsy were the main medical problem. They have complete primary dentition with normal dental morphology, tooth eruption altered, dental caries, and dental malocclusion was identified. Conclusion: There are no changes in the dental formula and dental morphology in the deciduous dentition. They present severe chewing and speaking limitation, facial disproportion, and occlusal problems that warrant dental and medical attention.

Evaluation of Swallowing Related Muscle Activity by Means of Concentric Ring Electrodes

Surface electromyography (sEMG) can be helpful for evaluating swallowing related muscle activity. Conventional recordings with disc electrodes suffer from significant crosstalk from adjacent muscles and electrode-to-muscle fiber orientation problems, while concentric ring electrodes (CREs) offer enhanced spatial selectivity and axial isotropy. The aim of this work was to evaluate CRE performance in sEMG recordings of the swallowing muscles. Bipolar recordings were taken from 21 healthy young volunteers when swallowing saliva, water and yogurt, first with a conventional disc and then with a CRE. The signals were characterized by the root-mean-square amplitude, signal-to-noise ratio, myopulse, zero-crossings, median frequency, bandwidth and bilateral muscle cross-correlations. The results showed that CREs have advantages in the sEMG analysis of swallowing muscles, including enhanced spatial selectivity and the associated reduction in crosstalk, the ability to pick up a wider range of EMG frequency components and easier electrode placement thanks to its radial symmetry. However, technical changes are recommended in the future to ensure that the lower CRE signal amplitude does not significantly affect its quality. CREs show great potential for improving the clinical monitoring and evaluation of swallowing muscle activity. Future work on pathological subjects will assess the possible advantages of CREs in dysphagia monitoring and diagnosis.