. 2017 Apr 1;9(4):e584–e589. doi: 10.4317/jced.53605
Copyright: © 2017 Medicina Oral S.L.
This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Figure 1.
Study design.