Fixed detachable dental attachment device, assembly and methods of using the same

A fixed detachable dental attachment device, comprising:

• a cap for securing a dental appliance having
• a first attachment portion adapted to be rigidly secured to the dental appliance,
• a body portion having an outer surface which engages the dental appliance,
• an open end and an inner cavity facing away from the dental appliance and having an inner end facing the open end and an annular wall extending from the inner end to the open end, and
• a retention head extending from the inner end of the inner cavity and having an enlarged end portion, the annular wall having a concave portion extending up to the open end, the concave portion being defined by a concave lip and an inner annular surface of the annular wall;
• an abutment comprising an upper portion and a second attachment portion, the second attachment portion defining a central axis, wherein the upper portion has a convex outer surface comprising an open end and a socket;
• a retainer ring engaging an annular ring extending from a sidewall of a cylindrical cavity of the socket to retain the retainer ring in the socket, wherein the retainer ring has a tapered, lower inner wall, and a tapered upper inner wall, wherein the enlarged end portion of the retention head extends into the socket and through the retainer ring to secure the cap onto the abutment with the convex outer surface of the abutment engaging the concave portion of the annular wall of the cap and the enlarged end portion engaging the tapered, lower inner wall of the retainer ring, such that the enlarged end portion of the retention head is in swivel engagement in the retainer ring in the socket and the concave lip and the inner annular surface of the concave portion of the cap is in direct swivel engagement with the convex outer surface of the abutment;
• and
• the upper portion of the abutment having a second axis that is pre-angled at a predetermined angle in the range from 5° to 45° relative to the central axis of the second attachment portion.