It is possible to place a neuromodulator on only one side, but given the dynamic nature of the muscles and smile caution should be had on achieving perfect symmetry. Be sure to discuss with your treating provider as to their opinion.
It can take up to two weeks to see your final result from Botox injections. Most patients begin to see some effect five to seven days after treatment. The effects will gradually wear off typically over three to four months.
When using BOTOX for unusual areas, i.e. gummy smile, you need to use a expert Botox injector only. Sounds like the treatments were done correctly. And the results are point on. YES! the lip appears to flatten when the orbicular oris muscle is paralyzed. Thus the longer, flat effect. And NO...
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Everything you need to know about Botox for Gummy Smile