Dysmasema: Persistent Decline in Masticatory Function Related to Aging and Systemic Factors

Abstract

Decreased masticatory function, which is termed 'masticatory dysfunction', has long been considered a sign and symptom of underlying oral diseases. Masticatory function usually improves when the underlying diseases are treated. However, in older patients with systemic diseases, persistent masticatory dysfunction may occur even after individuals receive dental treatment. In this narrative review, the authors review of the current research on masticatory dysfunction associated with systemic factors, and proposed the concept of Dysmasema - a persistent condition of masticatory dysfunction refractory to dental treatment and associated with aging and systemic factors. The rationale for the need for the new concept (i.e., Dysmasema) and the elements needed to identify Dysmasema - namely, low masticatory performance, subjective eating difficulty, and poor nutritional status - are addressed. This new proposal, which is based on clinical, epidemiological, and pathological perspectives, contributes to the precise diagnosis and treatment of older adults by linking masticatory dysfunction with systemic factors.

Keywords: Eating difficulty; Geriatrics; Mastication; Masticatory performance; Oral health.

Fig. 1

Associations between oral diseases, masticatory dysfunction, and Dysmasema. (A) Oral diseases, such as periodontitis or dental caries, which may lead to tooth loss, are associated with multiple forms of oral dysfunction, including lower masticatory performance and eating difficulties. Dental treatment that focuses on restoring deficits, such as periodontal treatment or dental implant surgery, improves masticatory dysfunction and nutritional status. (B) In contrast to the condition in which masticatory function is significantly improved by dental treatment (i.e., [A]), Dysmasema refers to the condition in which masticatory dysfunction is persistent, even when dental treatment is completed. Persistent masticatory dysfunction can be evaluated by lower masticatory performance, experience of eating difficulties, and worse nutritional status. Notably, in older adults with systemic diseases, systemic factors (e.g., sarcopenia or cognitive impairment) may have a greater impact on masticatory function. Therefore, identifying the underlying systemic factors may play a critical role in improving masticatory function.