See: Orientation jig
An orientation jig is a device that is created in the laboratory. This abutment transfer device is designed to correctly maintain a component’s positional relationship as it is transferred from the custom-designed cast to the patient’s mouth. Abutment transfer devices are available for use with both closed tray and open tray techniques.
A restorative dentist uses impression coping (i.e., transfer coping) to create a cast that is identical to the patient’s mouth. This cast is used to ensure that the correct position of the patient’s abutment or implant is attained at the time that it is placed. Although impression coping is appropriate for the creation of an abutment level or an implant level cast, the correct coping must be used in each circumstance (e.g., impression posts, transfer copings, etc.).
The abutment-implant interface is the area of the abutment connection where the prosthetic screw comes into contact with the abutment. There are several different types of abutment-implant interfaces, all of which are affected by the particular type of hardware used. Types of abutment-implant interfaces include straight matching, straight non-matching, straight one-piece, concave matching, concave non-matching, and concave one-piece. For proper fit and overall success of a dental implant, the abutment-implant interface must be flush with no space or micromotion in between the prosthetic screw and the abutment. If micro motion is detected, more torque may be applied, however, periodontists must be careful to avoid applying too much force. If the abutment-implant interface is not flush, the integrity of the implant may be compromised and the patient may have a higher risk of overall implant failure. What type of hardware is used usually depends on the preferences of the periodontist.
There are two different levels of impressions that can be made in implant dentistry — abutment-level impressions and implant-level impressions. Each type of impression has benefits and caveats, and which is used depends largely on the type of procedure that the patient needs to have and what the periodontists preference is. An implant level impression requires subgingival placement of copings, while abutment-level impressions are easier due to supragingival margins. Impression copings are necessary for implant-level impressions, however, in some cases they don’t need to be used with abutment-level impressions. However, custom abutment is typically not available with abutment-level impressions, and abutment modification may be needed in the mouth. A periodontist will perform a full examination and conduct several imaging studies, including potentially 3-D volume renderings, to determine whether abutment-level impressions or implant-level impressions are necessary to achieve the doctor’s and the patient’s desired results.