From the present study in group 2 (Nos. 3, 4, and 5), it was clarified that taste buds with a taste pore were first detected 6 to 8 months after surgery, but the number of regenerated taste buds did not increase between 1 and 2 years after surgery. In this group, there were 2 phenomena that are not usually observed. One is that regenerated taste buds were found only on the lateral border of the tongue and not on the dorsal surface. The CTN in combination with lingual nerve enters the tongue in the middle of the lateral border. From its entry into the tongue, it divides into 3 branches of which all 3 run forward and medially. The most lateral branch runs to the lateral border and tip of the tongue. The intermediate branch, which is the largest and penetrates the muscular layer of the tongue, innervates the largest part of the mucosa of the dorsal aspect of the tongue.21 Considering these anatomical aspects, it may be difficult for regenerated nerve fibers to penetrate the thick muscular layer and reach the dorsal surface of the tongue. On the other hand, it may be easy to regenerate on the surface of the lateral border. The second point is that taste buds were not functional throughout the follow-up period in group 2. Since confocal laser scanning microscopy and EGM were performed in the same area of the tongue (midlateral region), it was suggested that taste receptors were not expressed in the taste pore. Further study is necessary to verify whether or not taste receptors are expressed in the taste pore in group 2, although biopsy is needed to perform immunohistochemical study.