How does dental care cost more than surgery for an animal? One root canal and crown cost about 1500?

a spay for an animal cost about 300. Are dentists Criminals?
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A dog's tooth [for example] could be compared to an iceberg, 4 fifths of it are under the gum line. If you imagine an average sized dog that is some massive tooth requiring a lot of intricate deep work; the upper teeth almost go to the animal's brain making the work difficult and dangerous so I suspect that may be the reasoning behind it.
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