Research is not necessary, but is having an individual "thing" or "niche" that makes you a unique applicant necessary? Yes. Mine was volunteering in a specific category of places because it tied into my life's goals. You need something on your application such as an extracurricular that helps the adcom view you as an individual strength necessary to the future dental class. For some, it may be research.
I wouldn't do research if you "think you need to have it". But if its something that really interests you then go for it. All dental schools are different though and I would read up on your target schools and maybe ask their offices what they think.
I say go with it if you have the access, it's pretty much safe to do activities that pre-health/pre-med would do as well for pre-dental, such as research.
Research might open your eyes to something you really love! And, I think it will really help your application. I've done research and it will be a big part of my app
I was told during an interview that they did not care about how much research experience I had conducted. "We are going to teach you how to do research OUR way" 😵