[1] Univ Modena & Reggio Emilia, Dept Surg Med Dent & Morphol Sci Transplant Surg O, Unit Dent & Oral Maxillo Facial Surg, Largo Pozzo 71, I-41124 Modena, Italy
[2] Univ Modena & Reggio Emilia, Dept Biomed Metab & Neural Sci, I-41125 Modena, Italy
[3] Univ Modena & Reggio Emilia, Environm Genet & Nutr Epidemiol Res Ctr, Dept Biomed Metab & Neural Sci, Sect Publ Hlth, I-41125 Modena, Italy
[4] Univ Calif Berkeley, Sch Publ Hlth, Berkeley, CA 94704 USA
[5] Boston Univ, Sch Publ Hlth, Dept Epidemiol, Boston, MA 02118 USA