This review shows that there is consensus in the literature that (meticulous) tooth brushing once per day is sufficient to maintain oral health and to prevent caries and periodontal diseases. Tooth brushing is also regarded as an important vehicle for application of anti-caries agents, such as fluorides. However, most patients are not able to achieve sufficient plaque removal by performing oral hygiene measures at home. Therefore, tooth brushing twice daily is recommended by most of the dentists in order to improve plaque control. This rule is followed by most of the patients taking care for their oral health and has shown to be effective in maintenance of oral health in numerous studies. Study of the literature gives no clear evidence as to the optimal time-point of tooth brushing (before or after meals). However, in order to eliminate food impaction and to shorten the duration of sucrose impact by tooth cleaning after meals seems to be recommendable. Although--with our current knowledge of potential harm due to brushing of erosively altered and softened tooth surfaces--giving advice on a more individual basis is recommended for patients suffering from erosion.