Evaluation of the maximum isometric tongue force of healthy volunteers

Severity of tongue base collapse in various body positions in patients with obstructive sleep apnea: A trajectory analysis

BACKGROUND

Drug-induced sleep endoscopy (DISE) is used for evaluating upper airway anatomy and determining airway obstruction patterns. It is typically performed with the patient in the supine position. Airway collapse severity is influenced by body position and level of consciousness; the resultant dynamic changes may vary across patients. In this study, we evaluated the severity of upper airway collapse through awake endoscopy and DISE and identified factors affecting the pattern of airway collapse severity.

METHODS

This study included 66 patients with obstructive sleep apnea. The patients underwent type 1 polysomnography, tongue strength assessment, awake endoscopy in the sitting and supine positions, and DISE. Group-based trajectory modeling was performed to identify patients with different collapse severity patterns in different body positions and at different levels of consciousness.

RESULTS

Patient with similar severity trajectory were assigned to the same group. Two different severity trajectories (group 1 and group 2) were identified at the tongue base level. Tongue depression strength varied significantly between groups 1 and 2 (47.00 vs. 35.00 kPa; P = .047). During awake endoscopy, collapse severity was significantly higher in group 2 than in group 1. Group 1 had lower rapid eye movement/nonrapid eye movement apnea-hypopnea index ratios and higher tongue depression strength than did group 2.

CONCLUSION

In patients with obstructive sleep apnea, tongue strength may vary depending on body position. Our results should be interpreted with caution because of the limited sample size. Future studies should investigate the effect of oropharyngeal rehabilitation on tongue strength and collapse severity.

Enhancing the mechanical properties and surface morphology of individualized Ti-mesh fabricated through additive manufacturing for the treatment of alveolar bone defects

Titanium meshes are widely utilized in alveolar bone augmentation, and this study aims to enhance the properties of titanium meshes through heat treatment (HT) and the synergistic finishing technology of electric field and flow field (EFSF). Our findings illustrate that the titanium mesh exhibits improved mechanical properties following HT treatment. The innovative EFSF technique, in combination with HT, has a substantial impact on improving the surface properties of titanium meshes. HT initiates grain fusion and reduces surface pores, resulting in enhanced tensile and elongation properties. EFSF further enhances these improvements by significantly reducing surface roughness and eliminating adhered titanium powder, a byproduct of selective laser melting printing. Increased hydrophilicity and surface-free energy are achieved after EFSF treatment. Notably, the EFSF-treated titanium mesh exhibits reduced bacterial adhesion and is non-toxic to osteoblast proliferation. These advancements increase its suitability for clinical alveolar bone augmentation.

Reliability and Responsiveness of a Novel Device to Evaluate Tongue Force

BACKGROUND

Measurements of tongue force are important in clinical practice during both the diagnostic process and rehabilitation progress. It has been shown that patients with chronic temporomandibular disorders have less tongue strength than asymptomatic subjects. Currently, there are few devices to measure tongue force on the market, with different limitations. That is why a new device has been developed to overcome them. The objectives of the study were to determine the intra- and inter-rater reliability and the responsiveness of a new low-cost device to evaluate tongue force in an asymptomatic population.

MATERIALS AND METHODS

Two examiners assessed the maximal tongue force in 26 asymptomatic subjects using a developed prototype of an Arduino device. Each examiner performed a total of eight measurements of tongue force in each subject. Each tongue direction was measured twice (elevation, depression, right lateralization, and left lateralization) in order to test the intrarater reliability.

RESULTS

The intrarater reliability using the new device was excellent for the measurements of the tongue force for up (ICC > 0.94), down (ICC > 0.93) and right (ICC > 0.92) movements, and good for the left movement (ICC > 0.82). The SEM and MDC values were below 0.98 and 2.30, respectively, for the intrarater reliability analysis. Regarding the inter-rater reliability, the ICC was excellent for measuring the tongue up movements (ICC = 0.94), and good for all the others (down ICC = 0.83; right ICC = 0.87; and left ICC = 0.81). The SEM and MDC values were below 1.29 and 3.01, respectively, for the inter-rater reliability.

CONCLUSIONS

This study showed a good-to-excellent intra- and inter-reliability and good responsiveness in the new device to measure different directions of tongue force in an asymptomatic population. This could be a new, more accessible tool to consider and add to the assessment and treatment of different clinical conditions in which a deficit in tongue force could be found.

Fracture Load of an Orthodontic Appliance for Robin Sequence Treatment in a Digital Workflow

CAD/CAM technologies and materials have the potential to improve the treatment of Robin Sequence with orthodontic appliances (Tübingen palatal plate, TPP). However, studies on the provided suitability and safety are lacking. The present study evaluates CAD/CAM technologies and materials for implementation into the workflow for producing these orthodontic appliances (TPPs), manufactured by different techniques and materials: additive manufacturing (AM) and subtractive manufacturing (SM) technologies vs. conventional manufacturing. The fracture load was obtained in a universal testing machine, and the breaking behavior of each bunch, as well as the necessity of adding a safety wire, was evaluated. The minimum fracture load was used to calculate the safety factor (SF) provided by each material. Secondary factors included manufacturing time, material cost and reproducibility. Dental LT clear showed the highest fracture load and best breaking behavior among AM materials. The highest fracture load and safety factor were obtained with Smile polyether ether ketone (PEEK). For the prototyping stage, the use of a Freeprint tray (SF = 114.145) is recommended. For final manufacturing, either the cost-effective approach, Dental LT clear (SF = 232.13%), or the safest but most expensive approach, Smile PEEK (SF = 491.48%), can be recommended.

Tendon-like tether formation for tongue-base advancement in an ovine model using a novel implant device intended for the surgical management of obstructive sleep apnoea

Obstructive sleep apnoea (OSA) is a serious debilitating condition with significant morbidity and mortality affecting almost one billion adults globally. The current gold standard in the non-surgical management of airway collapse is continuous positive airway pressure (CPAP). However, non-compliance leads to a high abandon rate (27-46%). While there are multiple sites of airway obstruction during sleep, the tongue base is recognized as the key player in the pathogenesis of OSA. Poor outcomes of current tongue suspension devices are due to fracture, slippage or migration of devices. Three tongue tethering device groups, namely a polydioxanone/polyurethane combination (PDO + PU) treatment group, a PDO analytical control group, and a polypropylene (PP) descriptive control group, were implanted into 22 sheep (75-85 kg) in a two-phased study. After implant times of 8, 16, and 32 weeks, sheep were serially euthanized to allow for explantation of their tongues and chins. The PDO + PU devices remodeled during the 32-week implant period into a hybrid biological tendon-like tether through the process of gradual degradation of the PDO and collagen deposition as shown by electrophoresis, histology and mechanical testing. The control PDO device degraded completely after 32 weeks and the PP devices remained intact. The hybrid biological tendon-like tether exhibited a break-strength of 60 N, thus exceeding the maximum force to overcome upper airway collapse.

Maximum isometric tongue force in patients with obstructive sleep apnoea

Background

Obstructive sleep apnea (OSA) is a sleep disorder with a prevalence of 9–38%. The underlying pathology in OSA is a collapse of the upper airway. Especially in more severely affected patients, this collapse is often located at the level of the tongue base. Therefore, various implantable systems (anchors and ligament techniques) were developed to prevent or overcome this collapse. These systems are exposed to various forces. Different models have been developed to measure these forces and data comparing forces in healthy individuals with OSA patients are rare.

Purpose

Purpose of the study was to evaluate possible differences in tongue forces between healthy individuals and patients with OSA.

Method

To evaluate maximum isometric tongue forces, we conducted a matched pair design study including 20 healthy individuals and 20 patients suffering from OSA. Maximum isometric tongue forces were measured in an anterior/posterior direction with the help of self-designed new device that clamps the tongue.

Results

We could show that the maximum isometric force does not differ significantly in healthy individuals (10.7 ± 5.2N) from patients with OSA (14.4 ± 6.3N).

Conclusion

Currently there are no indications that maximum isometric tongue force does differ in healthy individuals and patients with OSA. Higher, as well as lower, tongue forces in patients with OSA seem not to differ from healthy subjects and therefore may not be needed to consider, in the development of tongue management devices, for OSA patients.

The Mechanical Properties and Biometrical Effect of 3D Preformed Titanium Membrane for Guided Bone Regeneration on Alveolar Bone Defect

The purpose of this study is to evaluate the effect of three-dimensional preformed titanium membrane (3D-PFTM) to enhance mechanical properties and ability of bone regeneration on the peri-implant bone defect. 3D-PFTMs by new mechanically compressive molding technology and manually shaped- (MS-) PFTMs by hand manipulation were applied in artificial peri-implant bone defect model for static compressive load test and cyclic fatigue load test. In 12 implants installed in the mandibular of three beagle dogs, six 3D-PFTMs, and six collagen membranes (CM) randomly were applied to 2.5 mm peri-implant buccal bone defect with particulate bone graft materials for guided bone regeneration (GBR). The 3D-PFTM group showed about 7.4 times higher mechanical stiffness and 5 times higher fatigue resistance than the MS-PFTM group. The levels of the new bone area (NBA, %), the bone-to-implant contact (BIC, %), distance from the new bone to the old bone (NB-OB, %), and distance from the osseointegration to the old bone (OI-OB, %) were significantly higher in the 3D-PFTM group than the CM group (p < .001). It was verified that the 3D-PFTM increased mechanical properties which were effective in supporting the space maintenance ability and stabilizing the particulate bone grafts, which led to highly efficient bone regeneration.

Tongue retaining devices for obstructive sleep apnea: A systematic review and meta-analysis

OBJECTIVE

Tongue Retaining Devices (TRD) anteriorly displace the tongue with suction forces while patients sleep. TRD provide a non-surgical treatment option for patients with Obstructive Sleep Apnea (OSA). Our objective was to conduct a systematic review of the international literature for TRD outcomes as treatment for OSA.

METHODS

Three authors independently and systematically searched four databases (including PubMed/MEDLINE) through June 26, 2016. We followed guidelines set within the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA).

RESULTS

Sixteen studies with 242 patients met criteria. The overall means±standard deviations (M±SD) for apnea-hypopnea index (AHI) decreased from 33.6±21.1/h to 15.8±16.0/h (53% reduction). Seven studies (81 patients) reported lowest oxygen saturation (LSAT), which improved from 79.8±17.5% to 83.9±8.6%. Four studies (93 patients) reported Epworth sleepiness scale (ESS), which decreased from 10.8±4.8 to 8.2±4.5, p <0.0001. Four studies (31 patients) reported Oxygen Desaturation Index (ODI) which decreased from 29.6±32.1 to 12.9±8.7, a 56.4% reduction.

CONCLUSION

Current international literature demonstrates that tongue retaining devices reduce apnea-hypopnea index by 53%, increase lowest oxygen saturation by 4.1 oxygen saturation points, decrease oxygen desaturation index by 56% and decrease Epworth sleepiness scale scores by 2.8 points. Tongue retaining devices provide a statistically effective alternative treatment option for obstructive sleep apnea.

Caracterização da força da língua por meio de medidas objetivas

RESUMO Objetivo: analisar a força axial da língua e parâmetros relacionados por meio do FORLING. Método: foram analisados os dados de 92 participantes, entre homens e mulheres, com média de 23,3±7,7 anos. Resultados: no parâmetro força média da língua, identificaram-se valores médios de 13,0 N, já para a força máxima observou-se valor médio de 18,3 N. A força média e a máxima da língua apresentaram correlação positiva e associação altamente significante (p<0,001). A energia acumulada pela língua indicou valores de 131,1 N/s. O tempo médio gasto para que se alcance a força máxima da língua foi de 3,8 segundos, indicando um efeito do treinamento ao se comparar a 1ª à 3ª medida, com redução dos valores (p<0,001). Conclusão: o instrumento demonstrou ser capaz de mensurar parâmetros importantes para o fonoaudiólogo, indicando ser uma promissora ferramenta complementar à avaliação clínica fonoaudiológica.