What Is Cracked Tooth Syndrome?

Cracked tooth is a kind of fine tooth crack that is not easy to find. It is more common in permanent molars, followed by premolars. It can cause a series of lesions in the teeth, pulp, apex, and periodontal.

Cracked tooth

Right!

Cracked tooth is a kind of fine tooth crack that is not easy to find. It is more common in permanent molars, followed by premolars. It can cause a series of lesions in the teeth, pulp, apex, and periodontal.

Chinese name

Cracked tooth

Foreign name

no

Subjects

biology

Explanation

A subtle tooth crack

In 1978, Silvestri and Singh divided teeth into complete fractures and incomplete fractures. Complete fracture can be divided into complete oblique fracture and vertical fracture. Complete oblique fractures are most commonly found in weak cusp fractures where large-area prosthetic teeth are present; complete vertical fractures refer to complete crown and root fractures. Incomplete cracks can also be divided into oblique and vertical directions. Incomplete oblique cracks refer to the origin of the oblique cracks on the occlusal surface of the crown, enter the tooth tip (involving one or more tooth tips) diagonally and eventually expand The subgingival or cementum, the fractured part is not separated from the tooth; the incomplete vertical fracture is originated from the enamel and extends to the dentin, and sometimes extends to the root of the tooth, and the crack is usually in the mesial or cheek tongue direction. Crossing one or two edges, the two parts of the tooth are not completely separated. Cameron et al. Proposed the "cracked tooth syndrome" in 1964, which refers to a fracture of unknown depth that originated in the crown of the tooth, penetrates the tooth tissue, and extends below the gingival, and may communicate with the medullary cavity and / or periodontal ligament. crack.

According to the 1997 American Pulp Disease Association classification of cracked teeth, cracked teeth can be divided into 5 categories: enamel surface cracks (crazeline), which are confined to the enamel and visible to the naked eye. Hidden cracks are usually visible in the posterior teeth across the edge and / or spread to the bucco-lingual surface; the front teeth usually have long, vertical recessed cracks. Fracturedcusp originates from the crown of the tooth, extends to the dentin, and ends at the neck of the tooth. A large area of prosthesis is often present in the affected tooth, and the tip of the tooth is broken due to the absence of the base glaze. Cracked tooth refers to the fracture line extending from the occlusal surface of the tooth toward the apex. It usually extends from the central fossa of the tooth to the mesial direction, and may involve one to two marginal ridges. The two parts of the tooth are not separated. Splittooth refers to the complete split in the mesial direction and extending to the edge of the tooth. vertical root fracture (verticalrootfacture), originated from the root of the tooth, mostly in the direction of the buccal tongue. The root fracture is usually complete or incomplete (only one face is accumulated), and may involve the entire root or a part of the root.

The causes of cracked teeth mainly include large and complicated fillings, poor cavity designs, developmental defects in the grooves, tooth wear, acid erosion and caries, excessive occlusal force, bruxism and occlusal trauma, etc., and its clinical symptoms It is usually related to the depth and direction of the crack. ^[1]

The occlusal surface can be seen to crack through 1-2 edges and reach the adjacent surface, often overlapping the developmental groove. Coated with iodine tincture, it can be seen that it penetrates into the cracks and shows a crack. Affected teeth may have symptoms such as cold, heat-induced pain, or spontaneous pain, which should be carefully checked to avoid missed diagnosis.

First of all, the patient's medical history and clinical symptoms should be carefully evaluated. Patients usually have a history of dental filling treatment, bad habits such as clenching teeth, night molars, or sudden hard bite. Typical clinical symptoms of cracked teeth are local sharp pain when chewing or biting hard objects or rough food, pain relief after pressure is removed, and unexplained sensitivity to cold stimuli. Clinically, a combination of percussion, bite, and pulp temperature tests is often required to check the patient's symptoms. Small rubber wheels, cotton rolls, wooden wedges, and polishing wheels are commonly used for bite testing. In addition, the suspicious area can be probed with a sharp probe, and patients often experience pain when pressure is applied to the crack. Periodontal probes can also be used to distinguish cracks from splits, as splits are often accompanied by deep periodontal pockets and poor prognosis.

If there is a large area of filling in the affected tooth, the original filling should be removed first to assess the degree of fissure, the condition of the pulp, and the remaining dental tissue structure. High sensitivity to cold stimuli and positive bite tests can make a diagnosis of cracked teeth. Common methods in clinical practice also include the use of optical fiber transillumination, intra-oral photography, and magnification (× 16) to enhance the visualization of cracks to assist exploration. The application of surgical microscope can also be used to assist the diagnosis and treatment of cracked teeth. Some scholars recommend using gentian violet and methylene blue to stain suspicious teeth, but this method takes a long time (at least 2 to 5 days) to work, and may require the wearing of a temporary crown, which is less clinically used.

If the diagnosis is still not possible, orthodontic stainless steel band rings can be worn on the suspicious teeth; if the patient's clinical symptoms ease after 2 to 4 weeks, the diagnosis is correct and the external splint is fixed to the cracked teeth; if the temperature-sensitive symptoms still exist , You need to consider the root canal treatment of the affected tooth. Apical radiographs have little effect on the diagnosis of cracked teeth. The direction of cracking is usually buccal-lingual, but it can be used to assess the condition of pulp and periodontal teeth of cracked teeth. For vertical root folds, cone-beam CT examinations can be used; in vitro studies have shown that cone-beam CT can detect smaller cracks with a thickness of 0.2 mm compared to X-ray examinations.

Studies have confirmed that ultrasonic tooth crack detection systems can clearly distinguish between simulated and cracked tooth surfaces. In addition, Sang-HeeLee et al. Proposed that optical coherence tomography (opticalcoherencetomographyOCT) can be used as a new method for diagnosing cracked tooth syndrome, which can produce precise tiny images, especially the swept-frequency OCT (SweptsourceOCT, SS-OCT) has a micrometer Level of resolution, can obtain deeper tomographic images of objects, is a non-invasive, reversible, accurate diagnostic method.

The primary purpose of tooth crack treatment is to stabilize and protect dental tissues, prevent further expansion of cracks, unrestrained movement of the cracked part under the action of chewing pressure and esophagus, and even complete cracking of the teeth to prevent saliva, Invasion of bacterial microorganisms. Asymptomatic patients can be used for preventive filling, and those who are symptomatic should be treated accordingly, and crown repair should be done in time.

Apply iodine stain to the suspected cracked area, wipe it with alcohol, and observe. If stained cracks are observed, it can be diagnosed as cracked teeth. Or you can use a suspicious tooth to bite a toothpick, showing a short tear-like pain, showing that the tooth has cracked.