The interdental brush and its place in operative and crown and bridge dentistry.

The effect of the interdental brush was evaluated on sixty-seven extracted teeth which were stained and examined under the stereomicroscope. Thirty-one of the teeth were totally covered with plaque when the interdental brush was used on them immediately before extraction. Thirty-six of the teeth were from patients who had used the interdental brush routinely for several years. The interdental brush was found to have an excellent effect both in the central part of the interdental space and on the embrasures. However, the most noteworthy finding was that it removes plaque as far as 2-2 1/2 mm below the gingival margin. This means that restorations can be kept free of plaque, even if they are extended into the pocket. In modern dentistry 'extension for prevention of dental caries' has become a controversial principle because subgingival restorations retain plaque which induces destructive periodontal disease. In many cases this problem can be solved by introducing the interdental brush.