Oro-facial impairment in stroke patients

Stroke is considered one of the leading causes of death and acquired disability with a peak prevalence over the age of 80 years. Stroke may cause debilitating neurological deficiencies that frequently result in sensory deficits, motor impairment, muscular atrophy, cognitive deficits and psychosocial impairment. Oro-facial impairment may occur due to the frequent involvement of the cranial nerves' cortical representation areas, central nervous system pathways or motoneuron pools. The aim of this narrative, non-systematic review was to discuss the implications of stroke on oro-facial functions and oral health-related quality of life (OHRQoL). Stroke patients demonstrate an impaired masticatory performance, possibly due to reduced tongue forces and disturbed oral sensitivity. Furthermore, facial asymmetry is common, but mostly discrete and lip restraining forces are reduced. Bite force is not different between the ipsi- and contra-lesional side. In contrast, the contra-lesional handgrip strength and tongue-palate contact during swallowing are significantly impaired. OHRQoL is significantly reduced mainly because of the functional impairment. It can be concluded that impaired chewing efficiency, dysphagia, facial asymmetry, reduced lip force and OHRQoL are quantifiable symptoms of oro-facial impairment following a stroke. In the absence of functional rehabilitation, these symptoms seem not to improve. Furthermore, stroke affects the upper limb and the masseter muscle differently, both, at a functional and a morphological level. The rehabilitation of stroke survivors should, therefore, also seek to improve the strength and co-ordination of the oro-facial musculature. This would in turn help improve OHRQoL and the masticatory function, subsequently preventing weight loss and malnutrition.