yes canine teeth are present in ruminants
Caribou do not have upper teeth because they only need to gulp food directly into their mouth and have no need to grab or shred it with upper teeth. Therefore, like other ruminants, they lack these teeth because they are unnecessary for their eating habits.
They are flat molars, similar to that of a human's. Cows have molars both on the top and bottom jaws. Do not confuse incisors with molars, because it's the incisors (the front teeth) that cows and other ruminants lack that make people say they have "no upper teeth."
Ruminants lack upper incisors. What they do have is a hard pad which they grind their food or regurgitated food against.
goats have no teeth in the upper front
Camels have a three-chambered stomach, not four. True ruminants have the typical four-chambered stomach, but camelids like camels do not. They also lack the characteristic rumen, only having the reticulum, omasum and abomasum.
There probably is some need of dental care for ruminants but the number of ruminants that will live long enough to need dental care and are valuable enough to merit such care is very low. In general, when a ruminant's teeth are no longer working properly, the animal is either sent to slaughter or is humanely euthanized. The one major exception to this would be teeth extractions of molars due to severe infection - most large animal veterinarians will surgically remove the affected teeth and clean out the nidus of infection.
Ruminants rely on bacteria in their rumen to break down cellulose found in grass into simpler molecules that can be digested by the animals. Without these bacteria, ruminants lack the enzymes necessary to break down cellulose on their own, making grass indigestible for them.
No. Camelids like alpacas, llamas and camels are pseudo-ruminants because they have the same foregut-fermentor activity as true ruminants do, but lack the rumen, since they only have three chambers in their stomach, not four. Rabbits are not considered pseudo-ruminants because they have a simple stomach and don't chew cud like pseudo-ruminants and ruminants do--even re-eating their feces doesn't even count as classifying a rabbit as a psuedo-ruminant. Thus they are simply hind-gut fermentors, and a monogastric.
If your teeth keep chipping off, it could be a lack of calcium in your diet. Other possible reasons could be decay or lack of other nutrients in the body.
teeth
Yes, birds are non-ruminants.