1995 Volume 37 Issue 4 Pages 695-705
The purpose of this study was to investigate the effect of removal of artificial plaque by ultrasonic cavitation from interproximal tooth surfaces with the interdental gingiva receded. For this purpose, we developed the newly tip capable of generating ultrasonic cavitation around the oscillating tip in water, and prepared two jaw models with different degrees of interdental gingival recession (exposed tooth crown surface and root surface). The tooth models in these jaw models were designated the upper central incisors (11, 21), the upper right canine and first premolar (13, 14), and the upper right first and second molars (16, 17). The areas of artificial plaque removed from the tooth crown and root surfaces were mesial in 11 and 14 and distal in 16, were momentarily measured in the two different methods to use the tip: the use by projection on one side, palatal or facial, and use on both sides. We also investigated the relationship between the rate of plaque removal and the shape of the interproximal space in each type of tooth. The following results were obtained. In the model with exposed tooth surface, the rate of plaque removal was the highest in 11 when the tip was used on the facial and palatal side. The reason was as follows: The distance between tips and the interproximal areas, and degree of the shadow for projection of cavitation at 11 were greater than other sites. In addition, the rate of plaque removal was the highest in 11 in the model with exposed root surface. These results suggested that the rate of plaque removed from all tooth models is affected by the distance between tips and interproximal areas or morphological factors in the interproximal space. When the tip was used on both the facial and palatal side, almost all the plaque was found to have been removed more effectively in a shorter time.
