An indirect bonding apparatus is made by initially placing spacer material over a replica of the patient's tooth structure. A tray is then formed over the spacer material and hardened. Next, the spacer material is removed from the tooth replica and orthodontic appliances are placed on the replica at...http://www.google.co.uk/patents/US7410357?utm_source=gb-gplus-sharePatent US7410357 - Method and apparatus for indirect bonding of orthodontic appliances
