Cats need their teeth brushed regularly to get rid of tartar and plaque buildup.If you can't brush your kitty's teeth, have his teeth professionally cleaned by your vet at least once a year.
A build up of plaque bacteria can infect the gums and structures which support the teeth. This can lead to gingivitis, a painful inflamtion of the gums and mouth, and if left untreated, periodontal. disease. Inflamed, infected gums are full of germs. Germs make the breath smell bad. If you notice redness just at the gumline chances are your kitty may have gingivitis. Chronic oral infection can also lead to disease in other parts of the body, including the heart, lungs and kidneys.
My kitty, Little Peepers, has had servere gingivitis since he was a kitten, due in part to a compromised immune system from irritible bowel disease. He eats a homemade diet that cleared up the irritible bowel but, despite home dental care, needs to have his teeth professional cleaned once sometimes twice a year. You want to talk about bad kitty breath?? Whew!! He's even had two molars extracted.
I guess I can't stress enough the importantce of home dental care. At the same time you don't want to get you or your kitty stressed out in the process. Ask your vet about a product called "Hexarinse" made by C.E.T.. It is an oral hygiene rinse for cats that you can use daily. It can aid in the prevention of tooth and gum disease. It is easy to use and if you can't brush your kitty's teeth I highly recommend it. Don't fall for the "dry food can clean your cat's teeth" claims. It doesn't. Ripping pieces of raw flesh (like the big cats) would go a long way in keeping down plaque and tartar but most people (myself included) don't want to feed their cats raw meat.
Sorry this has been so very long, but I hope this has been of some help. All my best in health and happiness to you and your kitty.