Correction to: Calcium and vitamin D supplementation and/or periodontal therapy in the treatment of periodontitis among Brazilian pregnant women: protocol of a feasibility randomis... oleh Paula Guedes Cocate, Gilberto Kac, Berit Lilienthal Hieitmann, Paulo Nadanovsky, Maria Cláudia da Veiga Soares Carvalho, Camila Benaim, Michael Maia Schlüssel, Maria Beatriz Trindade de Castro, Nadya Helena Alves-Santos, Amanda Farnum Baptista, Michael F. Holick, Rana R. Mokhtar, Alessandra Raymundo Bomfim, Amanda Rodrigues Amorim Adegboye