Efficacy of a new membrane obturator prosthesis in terms of speech, swallowing, and the quality of life of patients with acquired soft palate defects: study protocol of the VELOMEMBRANE randomized crossover trial.

BACKGROUND: Soft palate defects created during oral cancer surgery may prevent complete palatal closure and trigger palatopharyngeal insufficiency. One current treatment employs a rigid obturator prosthesis; an extension of acrylic resin at the level of the hard palate ensures surface contact with the remaining musculature. Unfortunately, airflow escape often causes hypernasality, compromises speech intelligibility, and creates swallowing problems (including leakage of food and fluid into the nasal airway). We plan to test a new removable denture featuring a thick dental dam that serves as a membrane obturator. The principal objective of the clinical trial is a comparison of speech handicap levels after 1 month in patients with acquired velar insufficiencies who wear either the new device or a conventional, rigid obturator. The secondary objectives are between-device comparisons of the swallowing handicaps and the health-related qualities of life. METHODS: The VELOMEMBRANE trial is a superiority, open-labeled, two-way, random crossover clinical trial. Adult patients exhibiting velar or palatovelar substance loss after tumor excision and who are indicated for rigid obturator-mediated prosthetic rehabilitation will be recruited in two teaching hospitals in France. Fourteen participants will be randomly allocated to wear both prostheses for 1-month periods in either order. The new membrane obturator is a removable resin prosthesis incorporating a rigid extension that holds a dental dam to restore the soft palate. The primary outcome will be the extent of phonation-related disability (the overall score on the Voice Handicap Index [VHI]). The secondary outcomes will be the Deglutition Handicap Index and health-related quality of life scores of the European Organization for Research and Treatment of Cancer (EORTC). DISCUSSION: High-quality evidence will be provided to document the utility of a new medical device that may greatly improve the management and quality of life of patients with acquired velar insufficiency. TRIAL REGISTRATION: ClinicalTrials.gov NCT04009811 . Registered on 4 July 2019.

Machine Learning Analysis of the Anatomical Parameters of the Upper Airway Morphology: A Retrospective Study from Cone-Beam CT Examinations in a French Population.

The objective of this study is to assess, using cone-beam CT (CBCT) examinations, the correlation between hard and soft anatomical parameters and their impact on the characteristics of the upper airway using symbolic regression as a machine learning strategy. Methods: On each CBCT, the upper airway was segmented, and 24 anatomical landmarks were positioned to obtain six angles and 19 distances. Some anatomical landmarks were related to soft tissues and others were related to hard tissues. To explore which variables were the most influential to explain the morphology of the upper airway, principal component and symbolic regression analyses were conducted. Results: In total, 60 CBCT were analyzed from subjects with a mean age of 39.5 ± 13.5 years. The intra-observer reproducibility for each variable was between good and excellent. The horizontal soft palate measure mostly contributed to the reduction of the airway volume and minimal section area with a variable importance of around 50%. The tongue and the position of the hyoid bone were also linked to the upper airway morphology. For hard anatomical structures, the anteroposterior position of the mandible and the maxilla had some influence. Conclusions: Although the volume of the airway is not accessible on all CBCT scans performed by dental practitioners, this study demonstrates that a small number of anatomical elements may be markers of the reduction of the upper airway with, potentially, an increased risk of obstructive sleep apnea. This could help the dentist refer the patient to a suitable physician.

Oral mucosal changes induced by adjuvant endocrine therapies in breast cancer patients: clinical aspects and proposal for management.

Adjuvant systemic treatments in breast cancer are indicated to reduce the risk of relapse. Their systemic side effects have been well documented and include menopausal symptoms such as impaired libido and vaginal dryness, increased risk of endometrial cancer, stroke, musculoskeletal symptoms including arthralgia and myalgia, osteopenia and fractures, skin rashes, and hypercholesterolemia. However, few articles have focused on the oral mucosal reactions related to adjuvant endocrine therapies (AETs) which clearly differ from those reported with chemotherapies or other targeted therapies used for breast cancer. AETs primarily expose patient to a higher risk of worsened periodontal health, salivary flow modifications, taste disturbance, and global deterioration of oral health-related quality of life. Although the rate of permanent discontinuation of AETs because of oral mucosal changes remains low, an interdisciplinary approach to evaluate oral health and to optimize oral supportive care appears essential to ensure an appropriate management and limit dose adjustment in treated patients. In this respect and based on our clinical experience, we propose recommendations to allow oncologists, nurses, and attending practitioners to implement appropriate measures rapidly and/or refer patients to dentists.

Periosteum Metabolism and Nerve Fiber Positioning Depend on Interactions between Osteoblasts and Peripheral Innervation in Rat Mandible.

The sympathetic nervous system controls bone remodeling by regulating bone formation and resorption. How nerves and bone cells influence each other remains elusive. Here we modulated the content or activity of the neuropeptide Vasoactive Intestinal Peptide to investigate nerve-bone cell interplays in the mandible periosteum by assessing factors involved in nerve and bone behaviors. Young adult rats were chemically sympathectomized or treated with Vasoactive Intestinal Peptide or Vasoactive Intestinal Peptide10-28, a receptor antagonist. Sympathectomy depleted the osteogenic layer of the periosteum in neurotrophic proNerve Growth Factor and neurorepulsive semaphorin3a; sensory Calcitonin-Gene Related Peptide-positive fibers invaded this layer physiologically devoid of sensory fibers. In the periosteum non-osteogenic layer, sympathectomy activated mast cells to release mature Nerve Growth Factor while Calcitonin-Gene Related Peptide-positive fibers increased. Vasoactive Intestinal Peptide treatment reversed sympathectomy effects. Treating intact animals with Vasoactive Intestinal Peptide increased proNerve Growth Factor expression and stabilized mast cells. Vasoactive Intestinal Peptide10-28 treatment mimicked sympathectomy effects. Our data suggest that sympathetic Vasoactive Intestinal Peptide modulate the interactions between nervous fibers and bone cells by tuning expressions by osteogenic cells of factors responsible for mandible periosteum maintenance while osteogenic cells keep nervous fibers at a distance from the bone surface.

Different sympathetic pathways control the metabolism of distinct bone envelopes.

Bone remodeling, the mechanism that modulates bone mass adaptation, is controlled by the sympathetic nervous system through the catecholaminergic pathway. However, resorption in the mandible periosteum envelope is associated with cholinergic Vasoactive Intestinal Peptide (VIP)-positive nerve fibers sensitive to sympathetic neurotoxics, suggesting that different sympathetic pathways may control distinct bone envelopes. In this study, we assessed the role of distinct sympathetic pathways on rat femur and mandible envelopes. To this goal, adult male Wistar rats were chemically sympathectomized or treated with agonists/antagonists of the catecholaminergic and cholinergic pathways; femora and mandibles were sampled. Histomorphometric analysis showed that sympathectomy decreased the number of preosteoclasts and RANKL-expressing osteoblasts in mandible periosteum but had no effect on femur trabecular bone. In contrast, pharmacological stimulation or repression of the catecholaminergic cell receptors impacted the femur trabecular bone and mandible endosteal retromolar zone. VIP treatment of sympathectomized rats rescued the disturbances of the mandible periosteum and alveolar wall whereas the cholinergic pathway had no effect on the catecholaminergic-dependent envelopes. We also found that VIP receptor-1 was weakly expressed in periosteal osteoblasts in the mandible and was increased by VIP treatment, whereas osteoblasts of the retromolar envelope that was innervated only by tyrosine hydroxylase-immunoreactive fibers, constitutively expressed beta-2 adrenergic receptors. These data highlight the complexity of the sympathetic control of bone metabolism. Both the embryological origin of the bone (endochondral for the femur, membranous for the mandibular periosteum and the socket wall) and environmental factors specific to the innervated envelope may influence the phenotype of the sympathetic innervation. We suggest that an origin-dependent imprint of bone cells through osteoblast-nerve interactions determines the type of autonomous system innervating a particular bone envelope.