As with all personal injury and medical malpractice claims, several factors determine how long a dental negligence claim will take. Many dental malpractice cases settle, but a settlement can come early in the process, or it may not happen until the eve of trial. The circumstances surrounding a dental mistake can be complex or relatively straightforward. The dentist's malpractice insurer may try to fight your claim all the way through trial. All of these variables mean that your lawsuit could take several months or well over a year.