Oral tactile sensitivity and masticatory performance are impaired in stroke patients

Abstract

SUMMARY Oro-facial impairment following stroke frequently involves reduced chewing performance, that is oral phase dysphagia. The aim was to investigate the sensitivity of oral tissues following stroke and its potential impact on masticatory function.Therefore, hospitalised post-stroke patients were recruited and compared to healthy controls. Outcome measures comprised masticatory performance employing a colour-mixing ability, that is a bolus-kneading test, maximum lip-and bite force and the one-point and two-point tactile thresholds. Food hoarding and prevalence of dry mouth were evaluated with ordinal scales. Twenty-seven stroke patients (age 64Á3 AE 14Á1 years) and 27 healthy controls (age 60Á8 AE 14Á3 years, P = 0Á254) participated in this study. The groups had similar numbers of occluding units. Stroke patients reported more frequently dry mouth sensations and food hoarding. The intra-oral tactile sensitivity on the contra-lesional side was significantly lower in stroke patients compared to controls (0Á0001 < P < 0Á0002), and significant intra-group side differences were found only in the stroke group (0Á0001 < P < 0Á0010). For the lip, both sides were less sensitive in the stroke group compared with controls. The experiments confirmed lower masticatory performance and lip force in the stroke group, but the bite force was similar compared to healthy controls. Oral sensitivity was correlated with masticatory performance when a global correlation model was applied. A stroke may affect the sensitivity of the intra-oral tissues contralesionally, thus potentially affecting chewing function. Rehabilitation should therefore not only focus on motor impairment, but equally stimulate the sensitivity of the oral tissues, employing dry ice application or similar specific treatments.

Masticatory ability improves after maxillary implant overdenture treatment: A randomized controlled trial with 1‐year follow‐up

“…Another factor contributing to the correlation between objective and subjective masticatory ability could be that the lower maximum bite force due to pain is the main contributor to the bad reports of masticatory ability by complete denture wearers and not due to their impaired mixing ability . It has been found that a higher bite force results in better chewing efficiency . However this statement mainly refers to methods that evaluate masticatory ability with brittle test foods, which are usually hard …”

Changes in masticatory performance of edentulous patients treated with single‐implant mandibular overdentures and conventional complete dentures

“…These tests rely less on the crushing and comminution of the test food, but more on the bolus forming and kneading . Therefore, these tests are not highly dependent on the maximum bite force, as the specimens are more deformable and often soft, but rather on the force, coordination and sensitivity of the soft tissues (eg, the tongue, palate and cheeks) that are affected by ageing itself, diminished capability of adaptation to the dentures and poor mandibular denture retention . Of course, the structures are less, if at all, affected by any implant therapy designed to stabilise the denture; consequently, these tests often fail to demonstrate a short‐term (up to 1 year) effect on chewing efficiency .…”

Two‐colour chewing gum mixing ability test for evaluating masticatory performance in children with mixed dentition: validity and reliability study

“…Maximum available bite force may be an important factor in the comminution test due to higher forces necessary to crush chewing substances, whereas this factor is less important when chewing gum is used. Bite force then becomes a significant predictor, when the forces are limited due to tooth loss or atrophy of the jaw closing muscles . For this reason, children in mixed dentition were recruited in this study, for their temporary decreased masticatory capacity during this stage, and also for better cooperation compared to children in primary dentition.…”

“…Masticatory performance can be assessed in an objective way by determining an individual's ability to grind or pulverise food before swallowing . MP has been reported to be affected by sex, age , body mass index , state of dental health, interocclusal relation, occlusal table size, number of posterior functional units, neurological status , intra‐oral sensitivity and occlusal contact area . Numerous methods have been used to determine MP such as the comminution test, sugar loss from chewing gum , photometric methods to quantify changes in colour and colour change in chewing gum .…”