If you have a crack in your tooth that has extended into the pulp, the tooth can be treated with a root canal. Some time after the root canal, a crown can be placed to protect the crack from spreading.
Common educational path's for CSI's include a degree in criminal justice or a specific degree in crime scene investigation. If you are already working and do not have the time to go to classes, there are CSI degree programs that you can earn online. Degree & Education Requirements for Crime Scene Investigators.
In rural agencies or smaller police departments, forensic science techs may only need a high school diploma. Investigators can also come from the ranks of sworn police officers, in which case, they bring their police experience to the job. This includes several weeks or months of training at their police academies.