A cracked tooth is a regular occurrence in general dentistry. It may be hard to diagnose, due to the fluctuations in the clinical presentation. The symptoms that arise from a cracked tooth have resulted in coining of the term Cracked Tooth Syndrome (CTS).
Cracked Tooth Syndrome
The term “cracked tooth syndrome” was coined by Cameron in 1964 and defined it as- an incomplete fracture of a vital posterior tooth that may or may not involve the pulp. Cameron stated that despite the awareness about cracked teeth among dentists, it’s neither often being reported in textbooks nor getting much of students’ attention. He also emphasized that the most important aspect of the diagnosis of the problem is its awareness. Even after fifty-four years, his statement sounds as true as ever.
Progression of Cracked Tooth Syndrome
A cracked tooth is seldom an unforeseen phenomenon. A crack normally progresses through three stages including initiation, propagation, and manifestation before it is visible. After its formation, a crack sometimes remains innocent and asymptomatic for years. However, drastic transformation occurs when the crack is exposed to the stresses of dental treatments that may or may not be relevant.
Cracks situated in the peripheral ridges and anatomic channels of clinical crowns are simple to detect and diagnose. They are normally superficial and visible to the bare eye. However, other cracks are not simply detectable. They can move deep in the crown system and then either outside into the periodontal ligament area or inside into the pulp enclosure walls and floor.
The actual problem of cracked teeth identification and treatment lies with the “hidden” cracks. These cracks can weaken virtually any kind of procedure, including preventive, restorative, endodontic, orthognathic, orthodontic, surgical, and periodontal treatment. This holds true even if care is administered responsibly. In these circumstances, a crack that is previously non-causative, asymptomatic, and innocent is modified as a result of a treatment. The crack then gets modified to a conducive crack or fracture that leads to pulpal, periodontal, or periapical pathologies.
Hidden cracks are frequently found in these situations:
- Above root surfaces that lie next to overly tapered, stripped, or punctured root fillings
- Below old amalgam fillings
- Below composite restorations that substituted old amalgam fillings
- Below crowns of teeth addressed endodontically
- On teeth treated using crowns or intracoronal restorations
Prevalence of the Silent Epidemic
Cracked teeth were represented by David Clark in Dentistry Today in 2007 as an “epidemic” and were more prominently mentioned as an “epidemic” at the 2015 American Association of Endodontists (AAE). It is now acknowledged as the third major cause of tooth loss due to which the AAE has recently designed a “Special Committee on Methodology of Cracked Tooth Studies.”
A study conducted by Hilton and Ferracane in 2013, referenced the prevalence of what can be safely called a cracked-tooth epidemic. Their work profited from a survey conducted by the Cracked Teeth Registry that was formed by the National Dental Practice-Based Research Network. The survey demonstrated the following results upon evaluation of 14,346 molars and 1,962 patients:
- 31.4% of all studied molars had a minimum of one crack
- 66.1% of patients had a minimum of one cracked molar
- 46.2% of patients had more than one cracked molar
- 10% of patients had a characteristic cracked molar
With the aging population in the United States, cracked teeth will potentially become more prevalent. “Aged dentition” not only promotes the incidence of gum disease, attrition, erosion, root caries, teeth crowding, abrasion, and parafunctional occlusion, but it also displays an increased number of cracks.
The dental literature has distinguished root canal planning and obturation as detrimental factors for cracks. In 1987, Gher et al. established that 71% of the teeth examined with root fractures appeared on endodontically treated teeth which led them to conclude that teeth with full crowns and restored with endodontic treatment do not prohibit root fractures.
Unfortunately, cracks are frequently originated by inappropriate or harmful dental aid, including the application of unsuitable dental materials.
In 2013, Luca De Rose observed that in examining tooth fractures, centering around crack origination is of more value than studying tooth capability and resistance to fracture. According to him, a fracture is often an outcome of an ongoing crack.
Going Forward with Educating Clinicians on the Problem of Cracked Tooth
The absence of a specific definition or clinically measurable criteria for the terms “crack” and “fracture” have caused confusion and wrong diagnoses. With training, it is manageable to remove common misinterpretations and disparity in knowledge about cracked teeth. In order to gain insight into the cracked-tooth problem, it is also essential to grow one’s understanding of treatment.
It is crucial to examine poor endodontic treatments, irrespective of the patient’s symptoms to offer a detailed understanding of the reasons for treatment failure and to exclude the presence of cracks. The treatment may require modification accordingly to avoid further disruption of the alveolar bone and deterioration of the crack.
Related Article: Cracked teeth: A more serious problem in 2018 than 1964