yes, they can do them through crowns with no problem. i had it done many years ago. i don't recommend a root canals, though:
good luck with any root canals. my dad had two root canals (5 altogether) that he paid a fortune on. one cost him $2,100 and the other $1,900. by the time you have them crowned and redone over and over, the cost gets up there. all of them had to be pulled and one coated the dr with blood and infection. a guy from nebraska just came here. he had 10 root canals, 5 of which his regular dentist pulled. he said they were so badly infected, he was afraid to pull the rest. and, i'm not making that up, i have his email and give it to whoever contacts me and needs it. i know everyone wants to keep teeth, so they think technology will help them save a dead tooth with no bacteria produced. it isn't even scientifically possible.
Dr. Weston Price's Research
Dr. Weston Price, the noted and honored dental researcher of the early part of this century, headed a team of America's finest scientific researchers, numbering 60 doctors. Their research was conducted under the auspices of the American Dental Association (ADA). From their 25 years of study, this research team published 25 scientific papers dealing with the effects of dead or endodontically treated teeth producing other diseases and disorders in remote areas of the body. The research was not only accepted by the scientific community, but served to form an important concept in medicine which is even taught today: the focal theory of infection. Anyone who has a prosthetic joint replacement or a mitral value prolapse will immediately understand this concept, as they cannot undergo any dental procedure without first being treated with certain antibiotics to stop the spread of bacteria from the mouth to remote areas of the body which may produce a fatal infection.
Since the advent of antibiotics, dentists and physicians have been taught that the focal theory of infection is erroneous and has no scientific basis. Further, they are taught that there is no modern evidence that endodontically treated teeth are the source of focal infections. However, again, recall that patients with joint replacements and certain heart conditions must take antibiotics before and after any dental procedures. Why? Because the bacteria which live in the mouth enter the blood stream because of the dental procedures and travel to the heart and joints, thus possibily causing severe and often fatal diseases. Now, think about what you've just read: how can any dentist or physician claim that the focal theory of infection has no scientific validity when dentists are required to premedicate their patients to avoid producing a distant or focal infection?