If the patient’s mandibular wisdom teeth have been completely extracted and the maxillary wisdom teeth have erupted, it is considered best to extract the maxillary wisdom teeth unless there are other teeth missing in the maxillary posterior region itself, because once there are no more wisdom teeth in the opposite jaw to serve as a support, the maxillary wisdom teeth will elongate downward, ultimately resulting in the maxillary wisdom teeth frequently biting into the mucous membranes of the posterior region below. Because of the improper eruption position of the maxillary wisdom teeth, it is often impossible to brush the teeth, which will likely lead to decay of the maxillary wisdom teeth, or food impaction in the neighboring space between the front teeth, which will affect the health of the front teeth in the long run. Therefore, whether the maxillary wisdom teeth are extracted or not mainly depends on whether its eruption position is appropriate, and whether there are wisdom teeth in the opposite jaw with which to bite.