Removable and adjustable abutment devices and methods of operation thereof

A securement assembly for adjustably retaining an oral appliance in an oral cavity, comprising:

• a sleeve comprising a sleeve frame having a bottom edge, a plurality of locking flaps comprising a first locking flap and a second locking flap, wherein the sleeve defines a lumen therethrough, and wherein the bottom edge is defined by a plurality of cutouts along the bottom edge,
• wherein the first locking flap has a first length dimension and the second locking flap has a second length dimension,
• wherein the first length dimension is different from the second length dimension;
• an abutment assembly comprising a frustum having a frustum surface and configured to receive the lumen of the sleeve,
• wherein the abutment assembly is defined by an undercut extending radially inward relative to a portion of the frustum surface, wherein the portion of the frustum surface is configured to be in contact with the plurality of locking flaps;
• and
• wherein the first locking flap and the second locking flap project radially inward relative to the sleeve frame for locking against an edge of the abutment assembly adjoining the undercut.