Some parameters that you need to be aware of:
The crest whitening patch may help you, but they're relatively weak and won't whiten all your teeth, and may leave a line that doesn't cover the entire tooth. It's not expensive, and we have patients who are satisfied with the results (until they see what we can do).
Within the 18-25 age group, the system that sells within one hour has a greater chance of success. Teeth are more receptive to whitening gel. After treatment, everyone's teeth were white. Not only because of the whitening agent, but mainly due to the opening of your mouth and the dehydration of a hot light (not a laser). Once again, a disqualified person: we have a very successful, sustained scaling treatment at the age of 62. I've stopped using our "zoom 2" system because I'm very disappointed with the results.
Your best result will be through the dental clinic's professional system. There are different systems available. If you are less than 25 years old, you can try the system in the office, but in my office, I won't even give you (remember, I no longer use it), because I can't guarantee the cost of the long-term results leads to similar.
