Biologically friendly orthodontic aligners

A system for repositioning teeth of a user in need thereof from an initial tooth arrangement to a final tooth arrangement, the user having a dental arch that comprises malpositioned (“MP”) teeth and normal-positioned (“NP”) teeth, the system comprising one or more cycles of successive appliances, each cycle of successive appliances including:

• (a) at least one first appliance having a geometry selected to reposition the teeth from the initial tooth arrangement to a first intermediate arrangement or the final tooth arrangement;
• (b) optionally one or more intermediate appliances having geometries selected to progressively reposition the teeth from the first intermediate arrangement to successive intermediate arrangements including a last intermediate tooth arrangement;
• and (c) at least one final appliance having a geometry selected to progressively reposition the teeth from the initial tooth arrangement or the last intermediate arrangement to the final tooth arrangement,
• wherein the appliances comprise successive locks having different geometries shaped to receive and allow the appliances to reposition teeth from one arrangement to a successive arrangement,
• wherein the locks comprise polymeric shells having cavities shaped to receive MP teeth and cavities shaped to receive NP teeth so as to resiliently reposition teeth from one arrangement to a successive arrangement, each of the polymeric shells having a labile/buccal (“L/B”) wall and a palatal/lingual (“P/L”) wall,
• wherein at least one shell of the polymeric shells has an occlusal side opening such that a tooth receiving the at least one shell has its occlusal surface exposed.