[1] Univ Med Ctr Giessen & Marburg, Med Ctr Dent, Dept Operat Dent Endodont & Pediat Dent, Campus Marburg,Georg Voigt Str 3, D-35039 Marburg, Germany
[2] Publ Hlth Dept Dist Marburg Biedenkopf, Schwanallee 23, D-35037 Marburg, Germany
[3] Justus Liebig Univ Giessen, Univ Med Ctr Giessen & Marburg, Med Ctr Dent, Dept Pediat Dent, Schlangenzahl 14, D-35392 Giessen, Germany