[Reproducibility of plaque formation in the dento-gingival region. 4]

The reproducibility of plaque was quantitatively determined in three twelve-day examination periods. The periodontium of the subjects was healthy; tendencies for plaque formation were extreme or slight. Plaque formation was studied on teeth 33 to 43; the vestibular surface was divided into 1,600 areas, according to topographic factors. The absence and appearance of plaque three times tends to indicate a causal event in that particular area. The results were as follows:1) The reproducibility of plaque formation with "slight" plaque patterns is no lower than with "severe" plaque patterns. 2) The dominating influence of the microrelief (surface roughness) compared with the macrorelief (form of the tooth, tooth position) and other factors holds true for subjects with a tendency for severe and slight plaque formation. 3) Plaque may be formed by several different factors; these factors will affect various topographic zones of the tooth surface differently. Many other differences were reported in subjects with severe or weak plaque formation. 4) Terms of preventive dentistry, the evaluation of surface roughness of the teeth, particularly with adolescents, is necessary in each dental practice.