It’s a lengthy operation, thoroughly removing the interior tissue from such a large, triple rooted tooth. It needs to be done by a specialist veterinary dentist.
When our boy had his root canal the tooth was less robust than his other teeth afterwards. But he had lost much more of it initially than Shamas has. A few more bits did chop off over time, but it didn’t matter as the tooth was dead and fully filled anyway. Our boy originally broke his on a large cow bone - that was the last time I ever gave a dog a weight bearing mammal bone.