TY - JOUR AU - Reitan, K TI - Principles of retention and avoidance of posttreatment relapse JO - Am J Orthod VL - 55 PY - 1969 DO - 10.1016/0002-9416(69)90050-5 L3 - PubMed-ID: 4890739 SP - 776 EP - 790 ER -