How risky is dental cleaning?

I have a young kitty and a senior kitty. The senior kitty (approx. 14 years old) I just adopted less than 6 months ago, so he hasn't been in my care very long.

I recently started a dental hygiene routine for my cats. I brush their teeth every night before bed with an enzymatic toothpaste and also use a dental spray formulated for cats.

While brushing, I noted that my young kitty's teeth look really good, but the senior's teeth aren't looking very good.

I'm taking him  to the vet today and am going to discuss dental health, among other things.

The question is, being that dental cleaning is done under general anesthesia, how risky is it? Is my cat more likely to die from the dental cleaning than from leaving his teeth in bad shape?  

Any insights would be appreciated.

I have had dental cleanings on 2 of my cats.

Boogie Bear had one in 2012 when she was 6.5 years old. My vet suggested it at her annual exam because her breath was a little bad and teeth were a little yellowed. I worried the entire day she was there at the vet. But she did fine. She didn't need any extractions.  Mostly she was just hungry after we got home. I know an IV was involved because they shaved part of one leg to insert it. I did notice a knot on that leg several months later. I had them look at it at her next exam. It was a follicular cyst, which they drained and tested and found to be benign. 

   
Jumbo had one in 2013 was also 6 (estimated, I don't know his age for sure). I had had him for a year at that point. The first year was spent getting his skin problems under control and healed. He did have very bad breath. They told me could need several extractions. Everything went fine with him as well. Luckily he didn't need any extractions after all. He was also very crank and hungry after we got home. They recommended another cleaning at his last exam a few months ago. I've haven't had the funds to do it yet and am also not sure how he'd do as a "senior". 

 
In both cases, they gave me an estimated cost sheet and the option for an additional blood panel at an additional cost before doing the cleaning. I felt comfortable declining the panel each time. They would require the blood panel if the cat is a senior. That way they can pin point any additional risk factors for the senior kitties. They did stress that there was the risk that the cat could die and I had to sign a consent form/waiver.

From my 2 experience so far, the only negative side effect I encountered was Boogie Bear developing the follicular cyst. And they weren't with senior cats at the time. Probably the best thing to do would be to talk to your vet about your concerns regarding the anesthesia and see if they require a blood panel as well. I was curious myself so I did a google search and found these other 2 threads on TCS that might be helpful to you as well.

http://www.thecatsite.com/t/257361/how-safe-is-it-to-have-a-14yr-old-cats-teeth-cleaned

http://www.thecatsite.com/t/218517/teeth-cleaning-on-senior-cat

CatMinionJess has given some great threads to read. 

Dental cleanings are a different risk to all cats, depending on their health. I've had several done for my boys with no problems, but the risk to your cat specifically is something your vet will address. There will always be options, such as the IV and a blood panel. Personally, I think a blood panel is really important, as it will let you know if there are any underlying health issues brewing that could cause complications with the general.

I do know that dental issues in older cats can get quite serious, so I'm glad you're looking into these now.

I agree about having a blood panel done.  Last year I was at the vet a lot with Noodles and sedation was something we discussed because she had a distinct murmur.  By the end of the year she was diagnosed with congestive heart failure; so at this point sedation is out of the question.  My girls are litter mates; but Mooch's heart is in good shape and she was able to be sedated for a liver ultrasound earlier this year.  I had a childhood cat who had awful teeth; so I've seen some of the problems that can come with dental issues.  It really depends on each cat's situation.  

Thank you all for taking the time to reply! I'm definitely going to talk to the vet about doing a blood panel first.