The innermost tooth generally refers to the wisdom tooth, which is the third molar. The innermost tooth pain is most likely due to the ectopic growth of the wisdom tooth, leading to the possibility of pulpitis, pericoronitis, etc. Since humans are evolving and food is becoming more and more refined, the jawbone is smaller than before, which results in not having enough space for the wisdom teeth to grow, making it easy for ectopic growth, blockage, and ambulation of wisdom teeth to occur. This situation will affect the contact relationship between wisdom teeth and surrounding soft tissues and neighboring teeth, thus forming a blind band, causing food embedding, which is not easy to clean, and will lead to the occurrence of pulpitis, caries, pericoronitis of wisdom teeth, decay of neighboring teeth, pulpitis, tooth loosening, periodontitis, etc. after a long time.