Effects of tooth loss and denture wear on tongue-tip motion in elderly dentulous and edentulous people

Delayed Swallowing Reflex is Overlooked in Swallowing Screening Among Acute Stroke Patients

BACKGROUND AND PURPOSE

Dysphagia in the acute phase of stroke contributes significantly to poor outcomes and is associated with the development of aspiration pneumonia and malnutrition. Therefore, an accurate evaluation of swallowing is necessary before initiating oral food intake. The modified water swallow test (MWST) and the repetitive saliva swallow test (RSST) are commonly used as bedside screening methods for swallowing dysfunction, but it is unclear whether other factors contribute to dysphagia and consequent aspiration. The purpose of this study was to identify characteristics that might be overlooked in screening tests.

METHODS

Participants were prospectively selected from patients hospitalized for stroke at the Suiseikai Kajikawa Hospital between August 1, 2016 and June 30, 2018. Inclusion criteria were conscious and stable medical condition, and patients who were diagnosed with dementia were excluded. A videofluoroscopic (VF) swallowing study was carried out on all patients who met the inclusion/exclusion criteria and who passed both the MWST and the RSST.

RESULTS

Aspiration was observed in 16 of 172 patients (9.3%) when swallowing 3 ml of water. These aspirated patients showed significantly delayed swallowing reflex on VF.

CONCLUSIONS

Swallowing evaluation using a combination of the MWST and the RSST is reasonably effective. However, patients who show a delayed swallowing reflex might be overlooked by this screening procedure.

Utility of the luminance standard deviation to quantify magnetic resonance imaging motion artifact induced by tongue movement

Clear magnetic resonance imaging (MRI) is required to diagnose tongue cancer. However, the absence of occlusal support may cause tongue movements which are known to introduce artifacts on the MR image. This pilot study compared the manifest of artifacts from the tongue at rest and during motion using luminance standard deviation (LSD) to quantify the artifacts, in dentulous subjects. Participants were ten dentulous participants (5 males, 5 females; age 31.50 ± 8.38 years) with occlusal support. MRI was conducted with the tongue at rest and during lateral movement. The LSD was measured in the regions of interest (ROI) in the axial and sagittal planes. Tongue movement evoked unclear MR images, compared with the images taken at rest. Statistical analysis revealed that the LSD significantly differed between the tongue at rest and in motion in the axial (P = 0.004) and sagittal planes (ROI-A: P = 0.002, ROI-P: P = 0.006). These findings suggest that tongue movement introduces motion artifact and the LSD responds quantitatively to the magnitude of artifacts. Future studies will evaluate whether a prosthetic device used to provide occlusive support can decrease these artifacts when analyzed using LSD.

Wearing complete dentures is associated with changes in the three-dimensional shape of the oropharynx in edentulous older people that affect swallowing

OBJECTIVE

To investigate the effects of wearing complete dentures on pharyngeal shape for swallowing in edentulous older people.

BACKGROUND

In the absence of complete dentures, edentulous older people often lose the occlusal support necessary to position the mandible, which leads to an anterosuperior shift of the mandible during swallowing. This may result in pharyngeal shape changes effecting swallowing function in older people. However, the details of this phenomenon are currently unclear.

MATERIALS AND METHODS

Participants were 17 older edentulous volunteers. Cone-beam computed tomography imaging was performed with the participant in the seated position and wearing (i) both maxillary and mandibular dentures, (ii) maxillary dentures only and (iii) no dentures. During imaging, participants were instructed to keep their mouth closed to the mandibular position determined in advance during swallowing for each denture-wearing condition. The volume, height and average cross-sectional area of the velopharynx and oropharynx were measured, and the positions of the epiglottis and mandible were recorded.

RESULTS

While the vertical height of the oral cavity and pharynx significantly decreased, the volume and average cross-sectional area of the oropharynx significantly increased when dentures were not worn (p < 0.01). The absence of dentures caused an anterosuperior shift of the mandible when swallowing and drew the epiglottis forward, resulting in expansion of the oropharynx where the tongue base forms the anterior wall.

CONCLUSION

The absence of dentures results in anatomical changes in oropharyngeal shape that may exacerbate the pharyngeal expansion caused by ageing and reduce the swallowing reserve.

Caracterização da pressão da língua em idosos

Objetivo Caracterizar a pressão da língua em idosos. Métodos Estudo transversal, com a participação de 45 idosos, de 61 a 96 anos, sendo 34 (75,6%) do gênero feminino e 11 (24,4%) do masculino, sem distúrbios neurológicos e cognitivos, sem histórico de câncer de cabeça e pescoço e de procedimento radioterápico. Consistiu na aplicação de questionário, com registro da presença ou ausência de queixa de problemas na deglutição, seguido da avaliação miofuncional orofacial, enfocando a mobilidade e tensão de língua. Para a mensuração da pressão da língua, foi utilizado o Iowa Oral Performance Instrument (IOPI). A análise dos dados foi descritiva, com nível de significância de 5%. Resultados A média do pico pressórico foi de 44,6 KPa (±16), com os valores mínimo e máximo entre 9 e 88 KPa. Houve correlação moderada negativa entre pico pressórico e idade. Os longevos apresentaram a menor média de pico pressórico e inferior ao padrão de normalidade. Houve diferença entre a média de pico pressórico e uso de próteses, tensão de língua e mobilidade de língua no estalo. Conclusão Houve diminuição moderada do pico pressórico da língua com o aumento da idade e redução pressórica com o decréscimo da tensão da língua e de sua mobilidade no estalo. Em contrapartida, os valores de pico foram maiores nos idosos que utilizam próteses dentárias, quando comparados aos que destas não fazem uso.

Impacts of wearing complete dentures on bolus transport during feeding in elderly edentulous

Prosthetic treatment with dentures is often required for the elderly who have reduced swallowing function. Therefore, it is important to understand the relationship between denture-wearing and feeding function from the perspective of swallowing. To clarify changes in bolus transport during feeding in elderly edentulous patients with or without complete dentures. Subjects were 15 elderly edentulous volunteers who were treated with maxillary and mandibular complete dentures. The test food was 10 g of minced agar jelly containing barium sulphate with a particle diameter of 4·0-5·6 mm. Lateral videofluoroscopy was performed to assess the position of the leading edge of the bolus, the bolus volume in each area at swallow onset, bolus transit time and the mandibular position during pharyngeal swallowing. There were significant changes between the bolus transport with and without dentures. Without dentures, the leading edge of the bolus at swallow onset fell from the valleculae area to the hypopharynx, and the bolus volume in the hypopharynx increased. Bolus transit time increased in the oral cavity, valleculae and hypopharynx. The mandibular position shifted anterosuperior direction. The results arose owing to anatomical changes in the oral and pharyngeal structure and the following functional changes: poor food manipulation, poor bolus formation and delayed swallowing reflex. Removing dentures in elderly edentulous individuals influences bolus transport during feeding, resulting in the exacerbation of the reduced swallowing reserve capacity that accompanies ageing, and may increase the risk of dysphagia.

Deglutitive tongue movement after correction of mandibular protrusion

OBJECTIVE

To investigate any change in deglutitive tongue movement following the correction of malocclusion by orthognathic surgery.

MATERIALS AND METHODS

The subjects were nine patients with mandibular protrusion. A control group consisted of 10 individuals with a similar age range and normal occlusion. Swallowing events before and after mandibular setback via sagittal split ramus osteotomy were recorded by cineradiography, and the tongue movement was analyzed. Time and linear measurements were compared before and after surgical treatment by the Wilcoxon signed rank test; control and test subjects were compared with the Mann-Whitney U-test.

RESULTS

Tongue-palate contact and the tongue-tip position changed after orthognathic surgery and became similar to those of the controls. Movements of the anterior and middorsal regions of the tongue did not change after orthognathic surgery and remained different from those of the controls.

CONCLUSION

Our findings suggest that tongue-palate contact and tongue-tip position during deglutition adapted to the corrected oral and maxillofacial morphology, but the anterior and middorsal regions of the tongue during deglutition may have been affected by pharyngeal constrictors rather than by the oral and maxillofacial morphology.

Effect of complete denture wearing on deglutition time: a cine-magnetic resonance imaging study

Purpose of the study was to evaluate the effect of complete denture wearing on deglutition time (DT), hyoid bone and larynx movements in edentulous patients with real-time balanced turbo field echo cine-magnetic resonance imaging. Subjects were examined by cine-magnetic resonance imaging in supine position during swallowing water. Two sets of images for 23 edentulous (with/without wearing complete dentures) and one for 23 dentulous patients were obtained. Radiographic outputs representing three consecutive deglutition stages (oral, pharyngeal and oesophageal) were provided to perform measurements. Deglutition time significantly increased when edentulous patients wore their dentures (mean 0·75 s increased to 1·17 s), whereas dentulous patients' DT was about 0·91 s (P ≤ 0.05). The duration of deglutition is crucial because prolonged pharyngeal transit times increases the risk of aspiration. Within the limitations of the study, complete denture wearing could increase the shortened DT of the edentulous patients.