Abstract: Bonding to calcified tissues, including human teeth, tooth dentine and bone, is achieved through the medium of crystal growth adhered to the tissue. The crystals preferably comprise gypsum crystals which are formed by contacting the tissue surface with a mildly acidic solution containing sulphate ions. An uncured liquid resin is applied to the crystal growth and is cured to achieve adhesion by micromechanical interlock with the crystal growth and by superficial penetration of the tissue surface.

Abstract: Bonding to calcified tissues, including human teeth, tooth dentine and bone, is achieved through the medium of crystal growth adhered to the tissue. The crystals preferably comprise gypsum crystals which are formed by contacting the tissue surface with a mildly acidic solution containing sulphate ions. An uncured liquid resin is applied to the crystal growth and is cured to achieve adhesion by micromechanical interlock with the crystal growth and by superficial penetration of the tissue surface.

Abstract: Placement devices for positioning orthodontic attachments, such as, brackets, on the lingual and facial side of teeth are described. A tooth engagement plate or other member, which engages the facial side of a tooth for lingual placement or the lingual side for facial placement, is mounted for pivotal movement at least about a horizontal transverse axis. An orthodontic bracket holder is mounted to a handle for both horizontal and vertical movement to permit placement of an orthodontic bracket on the opposite side of a tooth to that engaged by the plate. In operation, for lingual placement, the tooth engagement plate is positioned in engagement with the facial side of the tooth, the bracket is located in its desired position adjacent the lingual side of the tooth by up and down movement of the handle and vertical movement of the bracket holder.

Abstract: Bonding to calcified tissues, including human teeth, tooth dentine and bone, is achieved through the medium of crystal growth adhered to the tissue. The crystals preferably comprise gypsum crystals which are formed by contacting the tissue surface with a mildly acidic solution containing sulphate ions.