FUNCTIONAL DENTAL OCCLUSION MAY PREVENT FALLS IN ELDERLY INDIVIDUALS WITH DEMENTIA

To the Editor: More than one-third of persons aged 65 and older fall each year, and in half, falls are recurrent. The prevention of falls in this growing population is a primary concern for maintaining an adequate quality of life. Elderly persons with cognitive impairment and dementia have two times the risk for falls as cognitively normal elderly persons. It has been demonstrated that multifactorial assessment and intervention focused on these risk factors, including impaired gait and balance (postural instability), environmental hazards, drugs, and cardiovascular diagnoses, has been successful in preventing falls in cognitively normal elderly persons but not in the elderly with cognitive impairment and dementia. It can be hypothesized that primitive reflexes such as postural stability are more important for demented elderly. When in an upright position, permanent oscillations are generated to maintain balance. Sensorial afferents are provided from proprioceptive, tactile, vestibular, and visual receptors. Proprioception of the mandibular system arises from the masticatory muscular system and dentoalveolar ligaments. Poor or absent dental occlusion may decrease proprioception in this area, interfering with the stability of head posture. In this study, the incidence of falls in individuals with adequate dental occlusion is compared with that of those with inadequate dental occlusion. In addition, in a smaller pilot study, the effect of improved dental occlusion on occurrence of falls was investigated in subjects who had previously fallen recurrently. Subjects for this study were 146 ambulatory elderly persons who had been admitted to a special geriatric hospital for individuals with behavior disorders who were also suffering from severe dementia. Inclusion criteria limited subjects to those who could walk, with or without a cane, for all of their ambulation. Multifactorial assessments of each patient’s function, including the Mini-Mental State Examination (MMSE), and pharmacotherapeutic status were performed, and occupational therapists conducted daily group rehabilitations to maintain physical ability. One dentist (MY) classified each subject’s occlusion into one of three categories: Group AFnatural dentition with adequate function, Group BFpartially or fully edentulous but maintaining functional occlusion with dentures in either or both jaws, and Group CFfunctionally inadequate occlusion with no dentures. Subjects were also divided into two groups: the high falls group ( 2 falls during the previous year), and the low falls group ( 1 falls). In a smaller pilot study, denture treatment was provided for a small subgroup of high falls patients who gave informed consent. After denture delivery, the incidence of falls was recorded over 1 year. During the 1-year investigative period, 41 of 146 patients had recurrent falls. No differences between the high and low falls groups in proportion of women (75.6% vs 69.5%), mean age (83.1 6.4 vs 81.9 6.9), use of psychoneurotic medications (56.1% vs 61.9%), or mean MMSE score (9.6 6.7 vs 11.8 6.3) were found. Dental status was significantly different between the high and low groups (Po.001) (Table 1). In the high falls group, 10 patients (2 men and 8 women, mean age standard deviation 81.0 8.0, mean MMSE score 12.1 4.0) who gave informed consent received denture treatment. Conventional denture treatments were provided, and all patients used dentures after treatment. During the investigative period after denture delivery, three patients were excluded because they were comatose or dead. All of the seven remaining patients experienced decreased frequency of falls, with five patients experiencing one or no falls during 1 year of follow-up. Within the limits of this study, it was found that patients with functionally inadequate dental status had significantly more-frequent falls than those with functionally adequate occlusion composed of natural teeth, dentures, or both. Because tooth loss may result in a decrease in proprioception in the masticatory muscles or dentoalveolar ligaments, an associated perturbation of visual stabilization and postural imbalances may be induced. One study indicated that dental occlusal condition is associated with reduced lower extremity dynamic strength, agility, and balance function in elderly people. These findings suggest that functional occlusion of natural or artificial teeth may play an important role in generating an adequate posture reflex through mandibular stability, preventing falls. The current small intervention pilot study, which reconstructed occlusion with dentures, supports these finding. In conclusion, poor or inadequate dental occlusion may be a predisposing factor for falls in older people, and improving occlusion deserves attention as an approach to prevention of falls in elderly patients. A dental examination is recommended for inclusion in the standard health examination for elderly persons, especially those with symptoms of dementia.