I would imagine you would have to go back and get more fillers after a certain amount of time.
Fillers last anywhere from 6-9 months on the first injection and a little bit longer on each repeated visit. In general you would need to come back for re-treatment every 6-12 months depending on when you feel the look starts to fade.
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Fellow of the Royal College of Surgeons of Canada (FRCSC), Fellow of the Royal College of Physicians of Canada (FRCPC)
Fillers last anywhere from 6-9 months on the first injection and a little bit longer on each repeated visit. In general you would need to come back for re-treatment every 6-12 months depending on when you feel the look starts to fade.
International Society of Plastic Surgery (ISAPS)