I use the green XCP sometimes, but mostly I just free-hand it (have patients hold) when the rubber dam is on. endo in-progress x-rays take a lot of skills and practice and I find upper molars and lower premolars to be more difficult.
you hardly ever have to remove the rubber dam frame (if it's a plastic frame) or anything else (like bite block, suction, etc.) when taking an xray if you free hand. here are some tricks:
1) anterior teeth: with everything intact (frame in place) push the frame away from mouth, placing the sensor then have the patient hold with thumb. make sure the source cone is either down for up (not straight) to capture apex
2) lower molars: unhook RD frame on the opposite side, the top 2 or 3 corners only, flip the dam corner away from underneath the frame exposing oral cavity. ask the pt to stick the tongue out then roll it to the opposite side while placing the sensor under the dam next to the tongue. ask pt to relax their tongue and you will feel the sensor slide into place. the cone needs to be angled up from the mandible not straight on
3) upper molars/premolars: unhook RD frame on the opposite side, the bottom 2 or 3 corners only, flip the dam corner away from underneath the frame exposing the oral cavity. place sensor next to the tooth being worked on, have pt hold the sensor in place with their opposite index finger. if pt has trouble holding the sensor in place, you can place a wooden tongue depressor in the plastic sleeve right behind the sensor so the pt can hold this with their hand. some people use snap-a-ray. the cone needs to be angled down from the sinus not straight on.
there are many advantages to not removing the rubber dam frame when taking x-ray if you can help it (this is not possible if you use XCP). this way you can look back and forth when you angle your cone and align it directly with your sensor avoiding a cone cut because the frame is holding everything in place so the dam is not obstructing your view. when the frame is not there, the rubber dam gets bunched up inside pt's mouth and saliva all over the place contaminating the whole field. this also saves you a lot of time removing as little as possible.
