Wauters, Mariana, Stellamary Hernández, Israel Juárez, and Gastón Vergara. 2014. “Oral Hygiene, Periodontal Status and Treatment Needs in 12 Years Old Students, Castro-Chile, 2014.”. Journal of Oral Research 4 (1), 19-24. https://doi.org/10.17126/joralres.2015.006.