Ellwood R, DeVizio W. Caries Res 2017; 51: 167–169

A systematic review (Caries Res 2016; 50: 383–393) has questioned the findings claiming the efficacy of toothpastes containing 1.5% arginine and fluoride and the research ethics unpinning these findings. The authors of this letter repost the assertions made in this systematic review. Much of this letter revisits the issues the same authors published (RIGHT OF REPLY – A proud contribution: DOI: 10.1038/sj.bdj.2016.6) in response to an OPINION (Br Dent J 2015; 219: 567–569 – two of the authors in the OPINION published in Br Dent J were those who published the systematic review in Caries Res). The authors of the letter state that this systematic review was 'both out of date and in some instances factually incorrect.' Focusing on the research ethics, it is stated in the systematic review that several studies used a non-fluoride containing toothpaste as the control; this '...offers poorer protection against caries than the standard method... violates the basic principles of ethics in research.' Yet the authors of the letter state that permission to carry out these studies was granted by the local ethics committee [Institutional Review Board (Ethics Committee) of Sichuan University]. The Declaration of Helsinki – Ethical Principles for Medical Research Involving Human Subjects is unequivocal in stating that the international norms and standards upheld by Research Ethics Committees, '...must not be allowed to reduce or eliminate any of the protections for research subjects...' (Paragraph 23).'