This study was performed to know the cleaning effect of different types of toothbrushes. The head of toothbrush was designed to have same length of nylon bristles and same tufted space. Nine different types of toothbrushes were prepared as follows:
A. Trimmed shape
1. Straight trimmed to irregular height.
2. Straight trimmed to uniform height.
3. Convexly trimmed.
B. Diameter of bristles
1. 0.23 mm.
2. 0.33 mm.
3. 0.40 mm.
Eighteen patients who had no denture and were normal dentition were instructed to clean with modified Stillman's method for 5 minutes. Quantity of eliminated debris was calculated by specially prepared measure.
From the observation, the toothbrush that was tufted the widest bristles showed high effectiveness and it was significant at the 5% level by wholly-significant-difference method. Concerning the shape, the shape with straight trimmed to unifrom height showed high effectiveness, but it was statistically insignificant. During observation period, injuried gingiva by toothbrush was not observed.