Understanding the Standard Superimpositions

The standard five superimpositions are used to describe facial changes in the:

You cannot display superimpositions on top of the x-ray image or photo image. Only a set portion of the tracing is displayed for each.

The standard five superimpositions are as follows:

Ba-Na at NA:Ba-Na at NA: Alignment of the line between basion and nasion at the nasion point. Used to evaluate maxillary change and point A change.
Na-Po at ANS-PNS:Na-Po at ANS-PNS: Alignment of the line between soft tissue nasion and soft tissue Pogonion at the intersection of the line between ANS and PNS. Used to evaluate soft tissue.
Ba-Na at CC:Ba-Na at CC: Alignment of the line between basion and nasion at the point where a perpendicular line from center of cranium to the Ba-Na line. Used to evaluate facial axis change, chin growth, and upper molar position. Center of cranium is a constructed point, the intersection of the line between PT (Pterygo-Maxillary Fissure) and gnathion and the line between nasion and basion.
Go-Me at Me:Go-Me at Me: Alignment of the line between gonion and Menton at the Menton point. Used to evaluate tooth change within the mandible.
ANS-PNS at ANS:ANS-PNS at ANS: Alignment of the line between ANS and PNS at the ANS point. Used to evaluate dentition and anchorage requirements.