The Effect of a Masticatory Muscle Training Program on Chewing Efficiency and Bite Force in People with Dementia

A Proposal for a Multidisciplinary Integrated Oral Health Network for Patients Undergoing Major Orthopaedic Surgery (IOHN-OS)

The passing of the years of life physiologically leads to the accumulation of changes in tissues in the oral cavity, influencing dentition, chewing and swallowing mechanisms, and the oral microbiota. Some diseases and medications can aggravate oral symptoms and negatively influence eating behaviours, increasing the likelihood of becoming malnourished. This could make older individuals more vulnerable to complications when undergoing major orthopaedic surgery. Hidden infection foci in the oral cavity are a recognised cause of post-operative periprosthetic joint infections. Dysfunctional oral problems might also compromise feeding after surgery when good nutrition represents a fundamental aspect of a proper recovery. To manage these shortcomings, in this article, the authors hypothesise a multidisciplinary path of care named the Integrated Oral Health Network applied to major Orthopaedic Surgery (IOHN-OS). This peri-operative initiative would include pre-operative oral health screening and risk management by a dental team, patient education programmes before and after surgery, and bedside gerodontology actions like oral care and meal and eating support for fragile individuals. The IOHN-OS has the potential to reshape the concept of suitability for major orthopaedic surgery and generate momentum for designing community-based surveillance programmes that can keep the mouths of older subjects healthy for a long time.

Neurotransmission, Vasculogenesis, and Osteogenesis Activities are Altered in the Aging Temporomandibular Joint of the Senescence-Accelerated Prone 8 Mouse Model

BACKGROUND

Alterations in neurotransmission, vasculogenesis, and osteogenesis pathways that may play pivotal roles in age-related changes in the temporomandibular joint (TMJ) are poorly understood.

PURPOSE

This study aimed to measure the associations between gene and protein profiles in senescence-accelerated prone 8 (SAMP8) mice.

STUDY DESIGN

The investigators designed and used 3 groups of 2 mouse models: 1) early aging SAMP8 at 24 weeks of age and control SAMR1 at 12 and 24 weeks (each stage n = 12).

PREDICTOR/EXPOSURE/INDEPENDENT VARIABLE

The independent variable was investigated using 3 mouse models: an early aging mouse model and a control mouse model (12 and 24 weeks).

MAIN OUTCOME VARIABLE(S)

The primary outcome variables were CGRP, VEGF-A, CD31, LYVE-1, osteocalcin, osteopontin, type I and II collagen, and MMP-2. The secondary outcome variables were histological characteristics.

COVARIATES

Not applicable.

ANALYSES

The gene and protein expression profiles of neurotransmitters, vasculogenesis, and osteogenesis were identified by quantitative real-time polymerase chain reaction and dot blot analysis, respectively. The cellular localization of these events was verified by in situ hybridization and immunohistochemistry. Bivariate statistics were computed for each of the outcome variables. Statistical significance was set to a P value < .05.

RESULTS

The expression of CGRP mRNA in the bony mandibular condyle (BMC) of SAMP8 mice (SAMP8, 3.3 ± 0.39 vs SAMR1, 0.001 ± 0.0001) was high at 24 weeks of age (24 weeks) (P < .001). Higher numbers of cells positive percentage for CGRP (MF, SAMP8, 28.67 ± 1.60 vs SAMR 1, 6.36 ± 1.10; CMC, 27.5 ± 2.12 vs 9.00 ± 1.21; BMC, 31.31 ± 2.81 vs 7.85 ± 1.14) and VEGF-A (MF, 34.43 ± 2.45 vs 14.01 ± 1.28; MD, 32.69 ± 1.86 vs 8.00 ± 0.91; CMC, 36.60 ± 2.05 vs 14.19 ± 1.25 BMC 36.49 vs 12.59 ± 1.41) antibodies were found in the 24 weeks TMJ (P < .01).

CONCLUSIONS AND RELEVANCE

The neurotransmitter, vasculogenesis, and osteogenesis pathways are associated with TMJ aging in the SAMP8 mouse model. In the future, the SAMP8 mouse model may prove to be a robust model for identifying molecular and biochemical events underlying the effects of feeding, occlusal changes, and tooth loss in the aging TMJ.

Use of handgrip strength measurement as an alternative for assessing chewing function in people with dementia

Background

Chewing ability and handgrip strength can be independent explanatory factors of physical fitness. The usability of measurement procedures for assessing chewing function in people with dementia seems to be limited. This study aimed to show an association between handgrip strength and chewing function to enable the use of handgrip strength measurement as an alternative for determining chewing parameters in people with dementia. 

Methods

The data analysed here are part of the OrBiD (Oral Health, Bite Force and Dementia) pilot study. A total of 120 participants were assigned to five evaluation groups based on their cognitive abilities using the Mini-Mental State Examination (MMSE). The MMSE groups in this data analysis were “no dementia” (noDem, MMSE 28–30), “mild cognitive impairment” (mCI, MMSE 25–27), and “mild dementia” (mDem, MMSE 18–24). Handgrip strength, maximum occlusal force, and chewing efficiency were measured. 

Results

The Mini-Mental State Examination scores among all participants (n = 71) resulted in a median of 27 and a range of 18–30. An association between maximum handgrip strength and the cognitive impairment of the participants was shown. Nevertheless, the use of handgrip strength measurement as an alternative for determining chewing function was not verified in this study.

Conclusions

The feasibility and reliability of chewing function measurements in people with dementia should be investigated. Existing measurement procedures may need to be adapted or new assessments may need to be developed to be usable in people with dementia.

Trial registration

ClinicalTrials.gov NCT03775772.