Hi
@Windyone555
At only 9 weeks after your surgery, it's much too soon to be worrying about not getting full extension. ROM can continue to improve for a year, or even longer, after a TKR, and it's quite normal for extension to be slower to achieve than flexion, so there's no need to rush.
Do you remember these articles, from the recovery reading list that you were given earlier?
It's never too late to get more ROM!
It's worth the wait for ROM
Just in case someone is telling you that you have a limited time window in order to achieve ROM, read this article:
Myth busting: the "window of opportunity" in TKR
No matter how we work on it, my knee will not go straight. My range of motion is now at 110 degree bend, so that is improving every day. Worried about scar tissue, which may have been there since my arthroscopic surgery in August 2014. If there is scar tissue will I need surgery to fix it?
And there may be your answer! You don't have to work hard to achieve ROM. IN fact, working too hared can actually slow you down. Here's another article for you:
TKR: work “smarter” and not “harder”
Your flexion is already at 110, which is good. That proves you don't have harmful scar tissue. You won't need surgery.
Everyone gets scar tissue. That's a normal part of healing and it's what holds your wound together. If you didn't get it, your wound would open up again. The abnormal healing that PTs obsess about and wrongly call scar tissue is really called adhesions. If you can bear to read another article

heehee

this explains the difference:
Scar tissue and adhesions - what's the difference?
Now, slow down, and stop worrying. You've got plenty of time.