Dynamic change in the thickness of the masseter muscle between contraction and relaxation is associated with the masticatory function in older adults: a cross-sectional study

Abstract

Background: Decreased masticatory function contributes to malnutrition in the elderly. The purpose of our study was to explore whether the masseter muscle is involved in masticatory function in older adults and to help determine if the masticatory function of the elderly can be improved by exercising the masseter muscle.Methods: Random sampling was adopted in our research, and a total of 413 older adults from 9 nursing homes in China were recruited from March 10 to June 12, 2022. The thickness and echo intensity of their masseter muscles were assessed using ultrasound. Masticatory function was measured using a color-changing chewing gum, and the change of α* before and after chewing (Δα*) was defined as masticatory function.If Δα* <14.2 in males or <10.8 in females was masticatory dysfunction. Their number of molar occlusal supports (MOSN), comorbidity, oral diadochokinesis (ODK), maximum tongue pressure (MTP), and calf circumference (CC) were evaluated. Multiple linear regression analysis was performed to identify the factors independently associated with the masticatory function.Results: Of the 413 older adults, 179 (43.3%) had masticatory dysfunction. The average thickness of the masseter muscle between contraction and relaxation was 1.3 mm (range, 0.7-2.0 mm). The thickness of the masseter muscle and ODK decreased with age, while the echo intensity of the masseter muscle increased.The results of the multiple linear regression analysis showed that dynamic change in the thickness of the masseter muscle between contraction and relaxation (β=0.085; P=0.049), MTP (β=0.147; P=0.001) and MOSN (β=0.349; P<0.001), brushing teeth ≥2 times/day (β=−0.187; P<0.001), and CC (β=0.135; P=0.002) were independent factors affecting masticatory function.Conclusions: We found that masticatory dysfunction was prevalent among older adults in nursing homes in Southwest China, and the dynamic change in the thickness of the masseter muscle between contraction and relaxation was positively correlated with masticatory function. This result suggests that we can improve the masticatory function of the elderly by increasing the thickness of the masseter muscle between contraction and relaxation (e.g., by exercising the masseter).

Jawline Aesthetic Definition: Enhancement with Masseteric Augmentation Using Ultrasound-Guided Fat Transfer

“…Furthermore, hypotrophy and atrophy can affect facial muscles, including masseter muscle, which has functional and aesthetic consequences. 10 Different techniques have been described to address a weak or poorly defined jawline, but to our knowledge, none of them have used our approach, which directly enhances masseter muscle volume. This particular location is critical to address as vital structures pass through it, and improper technique can result in serious injuries to the passing structures.…”

“…Furthermore, hypotrophy and atrophy can affect facial muscles, including masseter muscle, which has functional and aesthetic consequences. 10…”

“…9 Conversely, atrophy and hypotrophy of the masseteric muscles are commonly observed in older individuals, often resulting in masticatory and deglutition disturbances. 10…”

“…9 Conversely, atrophy and hypotrophy of the masseteric muscles are commonly observed in older individuals, often resulting in masticatory and deglutition disturbances. 10 Fat transfer is the most appropriate approach for facial augmentation and rejuvenation, either as a standalone procedure 11,12 or in combination with other techniques. 13…”

Association between animal protein intake, oral frailty and calf circumference in middle-aged and older adults: a cross-sectional analysis from the Shika study

“…Further, frailty is associated with sarcopenia, of which one of the indicators is calf circumference (CC) 6 7. It has been reported that chewing8 9 and swallowing10 11 functional decline are associated with decreased CC. A cross-sectional study conducted on older adults has revealed that poor chewing function is significantly related to gastrocnemius muscle thickness, which is a component of the calf 8.…”