Effect of dentures on pharyngeal swallowing function in patients with dysphagia

Hyoid displacement during swallowing function for completely edentulous subjects rehabilitated with mandibular implant retained overdenture

BACKGROUND

Hyoid bone is attached to the mandible, tongue, larynx, temporal bone, and cervical spine via different types of muscles or ligaments. The tongue, mandible, and hyoid system play a crucial role in swallowing function. This within subject study aimed to evaluate the impact of mandibular implant overdentures on the displacement of the hyoid bones during the swallowing process.

METHODS

Twenty five healthy edentulous subjects were selected for participating in the study. New complete dentures were constructed for all the participants. Subsequently two dental implants were inserted in the canine regions of the participant's mandibular arch. In order to retain the mandibular prosthesis in place, ball attachments were incorporated into the mandibular dentures to convert them into implant overdentures. Using 10 ml of thin liquid bolus, videofluoroscopy swallowing examination was performed in three different oral conditions: without complete dentures (WCD), with complete denture (CDs), and with a mandibular implant overdenture (IODs). ANOVA with Bonferroni test was used to analyze the data in order to determine how the hyoid displacement varied throughout different oral conditions.

RESULTS

Compared to complete dentures, mandibular implant overdentures showed a significant decrease (P < 0.05) in both anterior hyoid displacement and duration of hyoid maximum anterior excursion (DOHMAE). However, there was a non-significant difference (P > 0.05) between the two oral circumstances in terms of superior hyoid displacement or duration for hyoid maximum elevation (DOHME). There is no penetration or aspiration for both complete denture and implant overdenture oral conditions.

CONCLUSION

Implant retained overdentures have a positive effect on hyoid displacement during swallowing of thin liquid bolus consistency relative to conventional complete dentures.

TRIAL REGISTRATION

Retrospectively registered (NCT06187181) 02/1/2024.

Biomechanical and Cortical Control of Tongue Movements During Chewing and Swallowing

Tongue function is vital for chewing and swallowing and lingual dysfunction is often associated with dysphagia. Better treatment of dysphagia depends on a better understanding of hyolingual morphology, biomechanics, and neural control in humans and animal models. Recent research has revealed significant variation among animal models in morphology of the hyoid chain and suprahyoid muscles which may be associated with variation in swallowing mechanisms. The recent deployment of XROMM (X-ray Reconstruction of Moving Morphology) to quantify 3D hyolingual kinematics has revealed new details on flexion and roll of the tongue during chewing in animal models, movements similar to those used by humans. XROMM-based studies of swallowing in macaques have falsified traditional hypotheses of mechanisms of tongue base retraction during swallowing, and literature review suggests that other animal models may employ a diversity of mechanisms of tongue base retraction. There is variation among animal models in distribution of hyolingual proprioceptors but how that might be related to lingual mechanics is unknown. In macaque monkeys, tongue kinematics-shape and movement-are strongly encoded in neural activity in orofacial primary motor cortex, giving optimism for development of brain-machine interfaces for assisting recovery of lingual function after stroke. However, more research on hyolingual biomechanics and control is needed for technologies interfacing the nervous system with the hyolingual apparatus to become a reality.

Association between denture use and food form in older adults requiring long-term care: A multicenter cross-sectional study

PURPOSE

This study aimed to determine whether denture use contributes to maintaining and improving food forms in long-term care facility (LTCFs) residents.

METHODS

In 888 residents of 37 LTCFs in Japan, the following were investigated: nutritional intake status, food forms, age, sex, Barthel index (BI), clinical dementia rating (CDR), number of teeth present, number of occlusal supports, swallowing function, and use of dentures. Among all residents, those who were well-nourished and had ≤9 occlusal supports were analyzed. Based on standardized criteria, the food forms consumed by the subjects were divided into two groups: dysphagia and normal diet, which were further classified into four levels. Analysis was performed using a generalized estimation equation with the four levels of food forms as dependent variables and age, sex, BI, CDR, presence of dysphagia, number of teeth present, and use of dentures as independent variables.

RESULTS

The final analysis included 622 (70.0%) residents. Of these, 380 (61.1%) used dentures. The analyses revealed that food form was significantly associated with age (adjusted odds ratio [OR], 0.98), BI (OR, 1.04), number of teeth present (OR, 1.03), presence of dysphagia (OR, 0.44), and use of dentures (OR, 2.82).

CONCLUSION

Denture use was associated with food forms among Japanese LTCF residents. This indicates that the use of dentures is related to the maintenance of food forms, even in the elderly who participate in few activities of daily living, have reduced cognitive function, and require long-term care.