An abutment impression coping typically comes in two different types — open tray impression coping and closed tray impression coping. Although what abutment impression coping technique is used depends entirely on the periodontists preferences, many periodontists prefer closed tray impression coping versus open tray. This is because with open tray impression coping, the periodontist must be certain they can find and access the impression coping screw to be able to remove the impression. Failure to do so with an open tray may lead to the impression becoming locked in the patient’s mouth. Although a closed tray impression coping does not have this problem and is generally easier to use, open trays are considered to be more accurate, especially in cases of multiple implants that will need to be splinted in patients who are partially or fully without teeth. This accuracy makes open trays preferred by many periodontists.