Hey do you mind telling me your stats when you applied? My stats aren't that great and I would like to get a sense of how helpful applying early would be
The only part of the application that requires deep thinking is your personal statement. "Why do you want to be a dentist and what qualities do you have that you think will make you a great candidate?" 4500 characters, not words, max.
Everything else is simple personal information, like education background, family, volunteer locations, dates, and hours. All things you should be able to answer easily.
I'd recommend getting your LOR's as soon as you can. I used Interfolio, an online storage site. Pay $10 and you're good to use it for a year. It's best to ask for your letters when your professors are least busy (AKA as soon as possible because by June, you'll have plenty of students asking for letters). Once your writers submit their letters, it will sit in Interfolio until you want to use them.
Applying early will never harm you unless you rushed your application. Applying early also doesn't guarantee you anything, but it's better than applying later.
I submitted my application three weeks after it opened, stats in the signature.