[1] McGill Univ, Fac Dent, Div Biomed Sci, Montreal, PQ H3A 1G1, Canada
[2] Univ Toronto, Fac Dent, Div Orthodont, Toronto, ON M5G 1G6, Canada
[3] Univ Nantes, Fac Dent Surg, Dept Periodontol, CHU Rmes Inserm,U1229 UIC11, F-44042 Nantes, France
[4] Dalhousie Univ, Fac Dent, Dept Dent Clin Sci, Halifax, NS B3H 4R2, Canada