MR sialographic assessment of the masseter muscle and the ductal kinking in patients with recurrent parotitis.

Dysfunction of the masseter muscle may cause pathological kinking of the parotid duct leading to parotitis; MR sialography is a non-invasive radiological examination that allows to evaluate dynamically the ductal system of the parotid glands. In the present study we aimed to assess the relationships between Stensen's duct and masseter muscle and their implications in the aetiopathogenesis of recurrent parotitis secondary to masseter muscle dysfunction. Forty-one patients with recurrent unilateral parotitis and nine with bilateral recurrent parotitis, all with a clinical suspicious of masseter muscle hypertrophy due to bruxism were enrolled. They underwent ultrasonography as a first line examination and then MR sialography and sialendoscopy. Different anatomical features were studied. Involved parotid glands had a wider duct compared to contralateral unaffected parotid glands of patients with recurrent parotitis (p = 0.00134); male subjects with parotitis had a longer duct compared to the salivary glands of healthy patients (p = 0.00943 for affected glands and p = 0.00629 for the contralateral). A concordance between the evidence of an acute duct angle during sialendoscopy and a wider duct in patients with parotitis was observed although not statistically significant. These initial findings suggest that the masticatory muscle dysfunction related to bruxism seems to condition alteration of parotid duct course and anatomy thus favouring the occurrence of recurrent parotitis. A specific diagnostic iter based on clinical evaluation, dynamic ultrasonography and MR sialography, is therefore, mandatory to confirm the relationship between masseter muscle anatomy and parotid duct anomalies; this is the premise for an adequate therapeutic approach to underlying masticatory muscle disorder.

Feasibility of 3D printed salivary duct models for sialendoscopic skills training: preliminary report.

PURPOSES: To explore the feasibility of 3D printed salivary duct models for the sialendoscopic skills training. METHODS: Healthy volunteers and patients affected by obstructive salivary gland disorders were submitted to 3 Tesla MR sialography. The MR data underwent an image segmentation process to produce the 3D printed salivary duct prototypes. Sialendoscopies were carried out by three groups of investigators with different levels of endoscopic experience. Realism, usefulness of the training process and potential advantages of the 3D printed models in the preoperative surgical planning were evaluated by means of a specific survey. RESULTS: Four cases were included in our study: one healthy parotid, one submandibular gland, one case of lithiasis and one of stenosis involving the parotid gland. In all cases, the three groups of investigators successfully explored the salivary ducts up to the tertiary branches, detected the cause of obstruction and correctly treated it. Seven untoward events occurred during the operative sialendoscopies. Overall, the questionnaire score was about 79.3%, reflecting a positive impression regarding the models on behalf of all the investigators. CONCLUSIONS: 3D printed salivary duct models resulted feasible for the sialendoscopic skills training. The opportunity to reproduce the patient-specific anatomy may add further information useful in the preoperative decision making. These positive results should be verified by further researches and experiences.

Recurrent parotid swelling secondary to masseter muscle hypertrophy: a multidisciplinary diagnostic and therapeutic approach.

PURPOSE: To present a patient with an atypical recurrent parotid swelling due to masseter muscle hypertrophy and the diagnostic/therapeutic assessment to treat this condition. CASE REPORT: A patient referring recurrent right facial swelling underwent a complete multidisciplinary assessment of the parotid region that revealed masseter muscle hypertrophy, confirmed by means of clinical (otolaryngological and gnathological evaluation), radiological (utrasonography, dynamic magnetic resonance imaging, and cone beam computed tomography), instrumental (electromyography to evaluate the right masseter muscle function and kinesiography to evaluate maximum right deflection - MaxRDefl and maximum opening - MaxMO) and sialendoscopy assessment where T0 indicates the pre-treatment values. All electromyographic and kinesiographic parameters were evaluated six months after the orthodontic application of a neuromuscular orthosis at T1. At T1, the effectiveness of the orthodontic therapy was demonstrated by the complete resolution of symptoms, and instrumental results documented more efficient muscle activity at rest and during clenching and a better mandibular position. At EMG T1, the resting and post-TENS values were, respectively, 1.2 and 1.8 microV. At kinesiography, MaxRDefl increased from 10.2 (T0) to 10.5 mm (T1); maxMO increased from 41.2 (T0) to 48 mm (T1). CONCLUSION: The proposed multidisciplinary assessment based on otolaryngological, gnathological, and radiological evaluation may be useful in the case of recurrent parotid swelling secondary to masseter muscle hypertrophy to plan an appropriate management with a removable neuromuscular orthosis.

Submandibular swelling: tooth or salivary stone?

Submandibular swelling is a common clinical disorder of the maxillo-facial region that may be one of the manifestation of several pathologic disorders including sialolithiasis. A 38-year-old woman experienced a recurrent painful swelling in the right submandibular region for seven years. The symptoms, not always meal-related, gradually became chronic and associated with dysphagia, odynophagia and fever. Ultrasonography of the salivary glands revealed a retained glandular structure and no ductal obstruction or dilatation, and orthopantomography showed the presence of a structure compatible with tooth, but these findings did not correlate with clinical scenario. Only CT dental scan identified the radiological image as a salivary stone. Sialolithiasis should always be considered in the diagnostic iter of painful submandibular swelling. A careful evaluation of recurrence and characteristics of signs and symptoms associated to the swelling can help in making the correct diagnosis and planning a proper therapeutic strategy.