Exploring the Effects of Using an Oral Appliance to Reduce Movement Dysfunction in an Individual With Parkinson Disease: A Single-Subject Design Study

Pilot trial of a mouthpiece as treatment for signs and symptoms of Parkinson disease

PURPOSE

Several case studies and anecdotal reports have shown assorted motor and quality of life benefits from use of a dental mouthpiece among people with Parkinson disease (PD). A larger exploratory study is necessary to assess potential efficacy and feasibility of this treatment strategy. If shown to be effective and feasible in a larger sample of people with PD, mechanistic studies may be warranted to examine a potential relationship between orofacial sensory input and motor function in people with PD.

MATERIALS AND METHODS

This study was registered on clinicaltrials.gov (NCT: 04082663). Twenty people with PD, Hoehn and Yahr stages I-III, participated in this study. Each participant completed various baseline motor and quality of life assessments before being fitted with a custom mouthpiece. Motor assessments were completed a second time after 25 min of mouthpiece wear. Participants were asked to wear the mouthpiece for 1 month before completing follow-up quality of life assessments and providing feedback about the mouthpiece. Wilcoxon signed-rank tests were used to compare results across conditions.

RESULTS

Gait velocity and cadence showed significant (p < .05) improvement while wearing the mouthpiece. However, these changes were not significant after correcting for multiple comparisons. Thirteen participants indicated they would be unlikely to continue wearing the mouthpiece.

CONCLUSIONS

These results do not provide adequate evidence to pursue further this type of mouthpiece as a treatment strategy for motor signs and symptoms or quality of life in people with PD.

Sensory-Challenge Balance Exercises Improve Multisensory Reweighting in Fall-Prone Older Adults

BACKGROUND AND PURPOSE

Multisensory reweighting (MSR) deficits in older adults contribute to fall risk. Sensory-challenge balance exercises may have value for addressing the MSR deficits in fall-prone older adults. The purpose of this study was to examine the effect of sensory-challenge balance exercises on MSR and clinical balance measures in fall-prone older adults.

METHODS

We used a quasi-experimental, repeated-measures, within-subjects design. Older adults with a history of falls underwent an 8-week baseline (control) period. This was followed by an 8-week intervention period that included 16 sensory-challenge balance exercise sessions performed with computerized balance training equipment. Measurements, taken twice before and once after intervention, included laboratory measures of MSR (center of mass gain and phase, position, and velocity variability) and clinical tests (Activities-specific Balance Confidence Scale, Berg Balance Scale, Sensory Organization Test, Limits of Stability test, and lower extremity strength and range of motion).

RESULTS

Twenty adults 70 years of age and older with a history of falls completed all 16 sessions. Significant improvements were observed in laboratory-based MSR measures of touch gain (P = 0.006) and phase (P = 0.05), Berg Balance Scale (P = 0.002), Sensory Organization Test (P = 0.002), Limits of Stability Test (P = 0.001), and lower extremity strength scores (P = 0.005). Mean values of vision gain increased more than those for touch gain, but did not reach significance.

DISCUSSION AND CONCLUSIONS

A balance exercise program specifically targeting multisensory integration mechanisms improved MSR, balance, and lower extremity strength in this mechanistic study. These valuable findings provide the scientific rationale for sensory-challenge balance exercise to improve perception of body position and motion in space and potential reduction in fall risk.