In terms of effect, it should be no problem for the prosthesis to fill the chin for a lifetime, because the current materials are very developed and the material science is progressing rapidly, so the silica gel put into the body, including the expansion body and artificial bone, will not age and deform, so if the shape has not changed, it doesn't matter if it is put into the body for a lifetime. Another point is that some patients, for example, when choosing MEDPOR artificial bone for chin augmentation, we need titanium nail for fixation, so after one year, this titanium nail may need to be taken out, so this is a problem; There is also the problem of bone absorption. No matter what kind of prosthesis, as long as it is placed in the body and contacts with the bone surface, the bone will be absorbed to a certain extent. Then different materials and different surface tensions, including different pressures on the bone surface, will affect bone absorption. On the whole, the bone absorption of artificial bone will be lower, and the bone absorption of silica gel will be higher. Sometimes, for example, we have been taking this kind of silicone prosthesis for chin augmentation for 10 years. In the process of taking it, we will find that the bone under the prosthesis will press out a big hole. In this case, sometimes the appearance effect may be affected to some extent. Then there will be patient feedback in clinic. They felt that the effect was quite good when they had just finished augmentation of prosthesis, but it was not obvious after a while, so bone absorption may be one of the reasons for this phenomenon.