Efficacy of dental prophylaxis (rubber cup) for the prevention of caries and gingivitis: a systematic review of the literature

Sometimes we do things in dentistry, or indeed in other parts of our lives because that is ‘the norm’; that is what we have deemed ‘accepted practice’. But what are these norms, these protocols based on? Is there any evidence for them, or are we carrying out procedures with no proven track record, and simply because it seems logical?