Expert: Mark Bornfeld DDS - 9/9/2007

Question
I saw a new dentist at my last cleaning because my prior dentist retired.  The new guy says my front tooth is "dead" and requires a root canal and crown.  The tooth is slightly darker than the other front tooth, but it has been this way for many years.  Approx. 30 years ago, I'm 47 now, the tooth  received an impact during wrestling practice.  I explained the history of the trauma and that I have no symptoms nor have seen any changes to the tooth in many years.  He was undeterred.  I'm thinking of going to another dentist for a second opinion.  What criteria are used to determine the vitality of a tooth?  Just how objective is the process?  What risks are involved in waiting for symptoms before fixing the "problem"?  Is a crown necessary with all root canals?

Answer
Dear Russ,

There are several criteria used to determine if a tooth is vital-- among them x-ray interpretation and use of an electronic pulp testing device. However, the darkening of a tooth, combined with a history of physical trauma, is almost unequivocal evidence of devitalization.

A more difficult question is whether such a tooth should receive root canal treatment. Sometimes, the need is obvious, such as when there are symptoms that indicate pulpal infection, or signs on an x-ray that there is either root or bone resorption in or around a tooth. In other cases, it's more a question of treatment philosophy. Some devitalized teeth never manifest signs of infection, bone resorption, or root resorption, but a dentist might feel that a root canal is necessary to prevent these adverse outcomes from becoming a reality. Other dentists may be more pragmatic, and may choose to assume a posture of watchful waiting to guard against signs of infection in the future-- only treating the tooth if infection becomes clinically evident. Neither stance is necessarily wrong, but may turn on the question of one's appetite for uncertainty in the future.

As for whether a crown is always necessary following a root canal therapy, the answer is no. However, there is a strong correlation between root canal therapy and crown fabrication, since severe injury or deep tooth decay that prompts root canal often causes structural damage to a tooth. In addition, the amount of tooth structure removed in the course of a root canal often further undermines the strength of a tooth. It is sometimes possible to avoid a crown following root canal treatment if there are no large fillings in the tooth, and the opening that a dentist creates in the tooth for the root canal is kept small. This is a judgment that a dentist must make intuitively, since almost any tooth may disintegrate even without a root canal, while some endodontically treated teeth remain structurally sound.

Hope this helps...

Mark Bornfeld DDS
www.dentaltwins.com
Brooklyn, NY