tooth fracture
The American Association of Endodontists has classified five different types of cracks in teeth.

In my last article, “Solving the Silent Epidemic of Cracked Teeth,” I discussed and reviewed the nature of and diagnosing cracked or fractured teeth. Now that you have seen or diagnosed a crack or fracture in a tooth, we need to first be able to classify or determine the type of crack and its extent before we can manage it. In this article, I will discuss and help define the five different types of fractures/cracks in teeth. 

Before we get to the five types of tooth fractures, let’s quickly look at a few cracks facts. Tooth cracks are either termed “complete” or “incomplete” fractures. This simply describes whether one (incomplete) or both (complete) marginal ridges are involved with the crack. Fractures or cracks in teeth can be as simple as a craze line into the enamel to as complex as a root fracture in the middle or apical third. Along with that, sometimes we can meet patients who have no symptoms at all to those who have pain on biting and constant pain associated with the cracked tooth.    

Cracked Teeth Types

Now that we’ve covered that, here are the five types of cracks in teeth, according to the American Association of Endodontists1:

Craze lines: Craze lines are commonly found in many adult teeth and only involve the enamel. They are often seen in unrestored teeth. Of course, it is not always easy to determine the extent or depth of a “craze line.”

Fractured cusp: Fractured cusp is a complete or incomplete fracture initiated from the crown of the tooth and extended subgingivally, usually going both mesiodistally and buccolingually. The fracture usually involves two aspects of the cusp, crosses the marginal ridge and extends down a buccal or lingual groove. 

Cracked tooth: A cracked tooth is an incomplete fracture that initiated from the crown and extends subgingivally and in a mesiodistal direction. It can go through one or both marginal ridges/proximal surfaces. 

Split tooth: A split tooth is a complete fracture that starts in the crown of the tooth and extends subgingvially in a mesiodistal direction, usually through both marginal ridges and the proximal surfaces. 

Vertical root fracture: A vertical root fracture is a complete or incomplete fracture from the root at any level and commonly runs buccolingually. 

Finally, a less common and more recently described2 cracked-tooth type is called a “fracture necrosis.” It describes a tooth that is non-vital with little to no restoration present and highly suggestive of fracture that extends from the occlusal surface into the pulp and progresses into the root surface. It is a specific type of vertical root fracture. 

Now that you have clarity on the types of cracked teeth, this will lead us to the final part of this series: how to manage and treat the cracked tooth based on how it classified. 

(Click this link for more dentistry articles by Dr. Jeff Lineberry.)

Jeff Lineberry, D.D.S., F.A.G.D., Spear Visiting Faculty and Contributing Author -


  1. Rivera EM, Walton RE.  Cracking the Cracked Tooth Code: Detection and treatment of various longitudinal tooth fractures. AAE, Colleagues for Excellence, Newsletter, Summer, 2008.
  2. Berman Lh, Kuttler S. Fracture Necrosis: Diagnosis, Prognosis, Assessment and Treatment Recommendations. JOE 2010: 36 (3): 442-446