[1] Columbia Univ, Coll Dent Med, New York, NY USA
[2] Univ Texas Hlth Sci Ctr Houston, Dept Periodont & Dent Hyg, Houston, TX 77030 USA
[3] Columbia Univ, Coll Dent Med, Div Prosthodont, New York, NY USA
[4] Univ Minnesota, Sch Dent, Dept Diagnost & Biol Sci, Hard Tissues Res Lab, Minneapolis, MN 55455 USA
[5] Columbia Univ, Coll Dent Med, Dept Periodont, Implant Dent, New York, NY USA
[6] Friedrich Schiller Univ, Univ Hosp Jena, Ctr Dent Med, Dept Conservat Dent & Periodontol,Sect Geriodont, Alten Post 4, D-07743 Jena, Germany
[7] Columbia Univ, Coll Dent Med, Div Periodont, Dent Med, New York, NY USA