There is a set of index marks for each cuspid and each first molar location. This is necessary because Opposing_Bases can be used as either an Upper or Lower. The lower cuspid and lower first molar in a normal mouth is usually anterior of the upper cuspid and upper first molar. Aligning the teeth to the correct index marks will insure a better relationship between the upper and lower models when articulated.
You do not have to be concerned with the index marks if the Opposing_Base is being used to pour a Triple Tray Impression on the Pouring Jig because the Opposing Index-Plate takes care of the alignment.
The Arch Opposing_Base can be used in place of a stone base. It comes in three sizes (small, medium and large) and can be used as an "Upper" or "Lower." It requires less than one forth the amount of stone over a solid stone base which will drastically lower material and shipping cost if applicable. It matches the RTP_Base which increases the overall esthetic value. It has retention pins on the bottom if you choose to mount it on a fixed articulator with plaster. You can also use a Mounting-Plate which has several advantages (less clean up, less weight and better overall appearance). Notice that the tongue area is capped which eliminates any stone in this area.
The Arch Opposing_Base is also used when pouring Triple Tray impressions on the Pouring Jig. You will notice a large, female sleeve on the bottom, anterior area which secures its position on the Opposing Index-Plate. Refer to the Home Page under section entitled "Using the System," and go to"Pouring Triple Tray Impressions (using the Pouring Jig)."
have a slot on the posterior surface to
receive a Vertex® or similar articulator
and is also designed to receive a Mounting-Plate...
Articulated Triple Tray System Bases do not need or contain this feature.