1. Master and Doctoral Program in Medical-Dental and Health Sciences at the School of Dentistry, National Autonomous University of Mexico, Ciudad de México 04510, Mexico
2. Faculty of Higher Studies (FES) Iztacala, National Autonomous University of Mexico, Tlalnepantla de Baz 54090, Mexico
3. Health Care Department, Metropolitan Autonomous University-Xochimilco, Ciudad de México 04960, Mexico
4. Dental Public Health Department, Graduate and Research Division at the School of Dentistry, National Autonomous University of Mexico, Ciudad de México 04510, Mexico
5. University Hospital for Conservative Dentistry and Periodontology, Medical University of Innsbruck, 6020 Innsbruck, Austria
6. School of Dental Medicine, University of Bern, 3010 Bern, Switzerland