A dental descale and polish is a procedure that requires a full anaesthetic. This is for a few reasons but the main ones are:
To allow a thorough job.
The descaling uses an ultrasonic descaler to remove the calculus. This has a tip that vibrates a tiny amount (less than 0.1mm) very quickly, When applies to the teeth this buzzes on the teeth and removes the hard calculus. Unfortunately dogs and cats do not like this buzzing and they will not sit still. To allow a good job, we need to anaesthetise them so that they remain still.
For your pet's safety.
The ultrasonic descaler sprays water onto the vibrating tip and onto the tooth being treated. This is to keep the tip and the tooth cool. This water can go down the windpipe if your pet is awake. To prevent this when they are asleep, your pet will have a tube placed in their windpipe and absorbant material packed around it.
Also, your pet may need manual descaling. This is done with sharp instruments that can get into the nooks and crannys. These require steady hands and a still patient.
All of the same recommendations before surgery apply to dental anaesthetics.
A toothbrush is the single most effective way of cleaning your pet's teeth, but there are a few things worth considering
Dogs and cats gums are much more sensitive than humans. They are more like a baby's gums. Use a special toothbrush designed for pets mouths.
Toothpaste is also too harsh for your pets. There are special toothpastes designed for pets and flavoured as beef, chicken, cheese, etc.
Only brush your pet's teeth once daily. Too often and you can damage the gums, too infrequently and you lose the benefit.
Start with short brushings and slowly build up to 1-2 minutes daily. Concentrate on the outsides of the teeth initially and then begin to brush the insides.