Effect of Jaw Clenching on Balance Recovery: Dynamic Stability and Lower Extremity Joint Kinematics after Forward Loss of Balance

Abstract

Postural control is crucial for most tasks of daily living, delineating postural orientation and balance, with its main goal of fall prevention. Nevertheless, falls are common events, and have been associated with deficits in muscle strength and dynamic postural stability. Recent studies reported on improvements in rate of force development and static postural control evoked by jaw clenching activities, potentially induced by facilitation of human motor system excitability. However, there are no studies describing the effects on dynamic stability. The present study, therefore, aimed to investigate the effects of submaximum jaw clenching on recovery behavior from forward loss of balance. Participants were 12 healthy young adults, who were instructed to recover balance from a simulated forward fall by taking a single step while either biting at a submaximum force or keeping the mandible at rest. Bite forces were measured by means of hydrostatic splints, whereas a 3D motion capture system was used to analyze spatiotemporal parameters and joint angles, respectively. Additionally, dynamic stability was quantified by the extrapolated CoM concept, designed to determine postural stability in dynamic situations. Paired t-tests revealed that submaximum biting did not significantly influence recovery behavior with respect to any variable under investigation. Therefore, reductions in postural sway evoked by submaximum biting are obviously not transferable to balance recovery as it was assessed in the present study. It is suggested that these contradictions are the result of different motor demands associated with the abovementioned tasks. Furthermore, floor effects and the sample size might be discussed as potential reasons for the absence of significances. Notwithstanding this, the present study also revealed that bite forces under both conditions significantly increased from subjects’ release to touchdown of the recovery limb. Clenching the jaw, hence, seems to be part of a common physiological repertoire used to improve motor performance.

Influence of controlled masticatory muscle activity on dynamic reactive balance

“…44 Since the clenching activity was performed before the perturbation and during the balance recovery, in these individuals clenching might also be part of the physiological repertoire during coping with demanding motor tasks. 11 However, further studies are needed to clarify this hypothesis.…”

“…5 There are a variety of studies indicating an influence of stomatognatic motor activity in the form of chewing, tongue activity or different clenching conditions in different jaw relations on human balance and posture under static conditions. [5][6][7][8][9][10][11][12] This means, in particular, a reduced body sway in the anterior-posterior direction, 8 a reduced variability of muscular co-contraction patterns of posture-relevant muscles of the lower extremities and reduced trunk and head sway under the influence of controlled biting activities. 9 This might be interpreted as a body sway stabilising effect.…”

“…The studies showed that oral-motor activities such as jaw clenching may contribute to increased postural stability, represented in terms of decreased postural sway in upright bipedal und unipedal standing. [8][9][10][11] To the best of our knowledge, the effects of motor activity of the masticatory system on dynamic balance have not yet been investigated in depth. 11 Therefore, the aim of this study was to investigate the influence of different functional stomatognatic activities on postural performance during a dynamic reactive balance task, which was operationalised with an oscillating platform perturbed in different directions.…”

Relationship between occlusal force and falls among community-dwelling elderly in Japan: a cross-sectional correlative study

“…Song-Yu et al [ 8 ] reported that elderly individuals with a partial lack of teeth had significantly less stable posture. Proper clenching excites the human motor system and affects human postural control [ 25 ]. In this study, we did not examine the relationship between MOF and denture use or between MOF and the number of remaining teeth.…”

Efeitos imediatos de interferência oral nos músculos mastigatórios e de interferência podal nas funções orofaciais, oclusão e postura corporal em jovens saudáveis

“…Os sistemas optoeletrônicos de captura de movimento atualmente disponíveis, como o BTS usado no presente estudo, foram considerados padrão ouro para análise de movimento em 3D (Robertson et al, 2004). Esses sistemas usam câmeras de captura infravermelha que rastreiam marcadores reflexivos passivos colocados na pele dos indivíduos, de modo que captam a posição 3D, isto é, as três dimensões no espaço de cada marcador ao longo do tempo, para cálculos subsequentes de parâmetros cinemáticos (Ringhof et al, 2015(Ringhof et al, , 2016.…”