Abstract
We investigated the brushing force, namely the denture brushing force, applied during mechanical cleaning with a tooth brush or denture brush.
The elderly subjects were four males and six females between the age of 66 and 85 years, who wore complete dentures. The dental staff subjects included four males and six females between 24 and 43 years, who had not worn dentures. Five kinds of denture brush and two kinds of tooth brush were used in this study. We recorded strain wave forms while the subjects were cleaning an experimental upper complete denture using the brushes with one-axis strain gages attached to their necks. Then, we converted the strain wave forms into force wave forms in the brushing plane, and measured the grip force for each subject.
In some series of cleaning actions by the elderly, there were short periods with no force to the brush. However, the dental staffs always applied force. The brushing rhythm of the elderly was slower than that of the dental staff. Also the denture brushing force of the elderly was weaker than that of the dental staff. There were positive correlations between the denture brushing forces and grip forces. The shape of bristles affected the denture brushing force. When the brush with a narrow brushing plane was used, the brushing force of the elderly was different from that of the dental staff.
Not all brushes which easily give brushing force for the dental staff are easy for the elderly. Thus, it is necessary to select the brush by having each elderly patient try them personally.
