Keep gels cooled if suggested to preserve strength; expired or warm-stored gels can underperform

https://zanderckjg432.timeforchangecounselling.com/in-office-vs-at-home-teeth-whitening-your-guide-to-expert-teeth-whitening-gilbert-and-affordable-teeth-whitening-gilbert-az

Keep gels refrigerated if suggested to maintain effectiveness; ended or warm-stored gels can underperform and produce irregular whitening results.