Thank you for sharing you concerns. Although your dentists assessment is most likely accurate, I would get a second opinion if you are not having any symptoms. It never hurts to have another professional opinion before committing to a series of interventions that could be taxing on your health and resources.
Although every surgeon has their own technique(s) for a Facelift/ Lower facelift/ Neck lift, the surgical intervention is focused on movement of the soft tissue. Once the neck is adequately addressed the tissue along the jawline and cheek is resuspended along the correct vectors to fixed structures like the periosteum in front and behind your ear. If your dental interventions include moving the teeth only and there is not any plan for changing the shape of the jaw (mandible), it should not matter when you have a facelift performed.
That said, a facelift is an elective procedure that should be performed when it works for you without adding additional stress or complexity to your life. Working with other physicians/dentist/medical professionals to make your experience perfect is the rule, not the exception. Once you have a firm idea about when/if you need the dental work done, I know that it will be coordinated to best meet your needs. I hope this helps. Take care.