Feline Dental Care?

On an episode of The Girls Next Door, Bridget's cat Gizmo had a visit from a cat dentist who put her in a "papoose" and cleaned her teeth without anesthesia. My question is - is this type of cleaning of the same quality as you would get when your cat is put under? And if so, why isn't it more common?
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It's definitely not as thorough as having the cat put under. At my clinic we only do teeth cleaning without anaesthesia under these conditions: the cat is well behaved and can't have anaesthetic due to age or medical conditions; or the cat is well behaved and needs a light touch up because it's more prone to dental disease than is normal. Remember, angry cats can be very violent. Everyone at my clinic would rather deal with an irate pitt bull than an angry cat. :)
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