If there is no occlusal relationship between the innermost tooth of the upper teeth and the opposite jaw, there is no effect of extraction, but if there is an occlusal relationship with the opposite jaw, the extraction will reduce part of the chewing efficiency. 1. With occlusal relationship: the last tooth of the upper teeth, depending on the oral condition, may be the second molar or wisdom teeth, if the growth position is positive and has occlusal relationship with the opposing teeth, it can exercise the function of mastication, the extraction will reduce some of the efficiency of mastication, so it is recommended that the second molar be restored as soon as possible after extraction. 2. No occlusal relationship: If the last tooth of the upper teeth has no occlusal relationship with the opposing teeth and does not exercise mastication, the extraction generally does not have much effect, such as wisdom teeth are generally recommended to be extracted. Extraction of teeth need to do a comprehensive physical examination to confirm that the body can withstand the extraction surgery, it is recommended to professional hospitals for examination and treatment.