This is usually placed on the lower second molars. Occlusal removal holes are placed in the occlusal surface of the crowns to aid in removal of the appliance, especially if a crown removal plier is going to be used. This hole can be made by the clinician at the time of MARA removal, but some clinicians find it easier to have them placed by the laboratory technician during fabrication. Maxillary occlusal removal hole. Mandibular occlusal removal hole.
Vent holes are much smaller and are requested to help extra cement escape from the crown.
Venting is not a necessary feature of cementation, but the name developed because of the venting observed during cementation, and is usually enlarged chairside later to facilitate crown removal. Do not use Vaseline of Chap Stick on the teeth if a crown removal hole or vent has been pre-cut in the occlusal surface of the crown. If there is a hole, the cement should set or cure before cleaning. Check for voids around the margins of the holes to avoid decalcification. When using glass ionomer cement with fluoride in it.