The second aspect that should be studied from an oral antiseptic, the antiplaque effect, is defined as the capacity that an agent has to avoid the formation of bacterial aggregates (plaque) on the oral surfaces. For its study in vivo, models start from a baseline sample with levels of plaque near to 0 in order to assess the power of the antiseptic to reduce the formation of bacterial plaque (normally dental plaque) against the control. A clinical study of 6 months using a determinate antiplaque agent is necessary in order to tag an antiseptic as effective. However, in the literature, there is an established model of 4 days of plaque regrowing which can assess the inhibitory activity that the mouthwashes have per se; furthermore, it determines the relative efficacy of the different formulations being considered as predictable of the antiplaque effect of an antiseptic.