A positioning plug (30) is connected with a positioning block (31).

Two ends of the elastic component (5) are respectively connected with the first positioning block (3) and the second positioning block (4).

A positioning groove (131) is formed in the push rod positioning block (13).

A plug body is provided with a positioning block, which can touch the general positioning switch.

The definition block (33) comprises a location block (332) and a clamping post (34).

The angle-adjustable mounting part comprises a base (101), a positioning block (102) and a rotating shaft (103) adaptive to the positioning block (102).

The apparatus comprises: an inner cavity positioning block (2), an external support body (3), an external positioning block (4), a mandrel (5), and clamps (6).

The positioning block (102) is mounted on the base (101).

The positioning block has a second inertial sensor unit producing orientation-based data for at least two degrees of freedom in orientation of the positioning block.

The design block and the positioning block are connected by means of multiple rod-shaped members.

The die (2) is equipped with a design block (20), a positioning block (24), and multiple rods (12).

An embellishment (18) is mounted on the foam, the embellishment carrying a locator block (24) which defines locator surfaces.

An adjustable marking and measuring tool including a locating block and a guide block is provided.

A parameter calculator calculates alteration parameters related to an actual orientation of the positioning block with respect to the bone as a function of the orientation reference and of the orientation of the positioning block.

The position of the guide block relative to the locating block is adjustable for adjusting the amount of reveal identified by the tool.