A sudden, sharp pain when biting down or a noticeable line on a tooth can signal a cracked tooth, often associated with Cracked Tooth Syndrome (CTS). A cracked tooth is a fracture plane that passes through the tooth structure. While cracks can be difficult to diagnose because they are often nearly invisible, they can quickly progress to affect the sensitive inner pulp. Professional evaluation is required to prevent potential complications like infection or tooth loss.
Identifying the Different Types of Tooth Cracks
Cracks are classified by their location and depth, ranging from minor surface defects to fractures that split the entire tooth. The most superficial type is the craze line, a tiny fracture restricted to the outer enamel layer that rarely causes pain and is usually cosmetic. A fractured cusp involves a break in the pointed chewing surface, often occurring around a large filling. This break can cause sharp pain upon release of biting pressure, but it typically does not extend into the pulp.
A true cracked tooth begins on the chewing surface and extends vertically toward the root, potentially affecting the dentin and pulp. If untreated, this can progress into a split tooth, where the fracture travels through the entire crown and root, dividing the tooth into two distinct segments. The most severe type is the vertical root fracture, which starts at the root and moves upward toward the chewing surface. This type often remains hidden, causing symptoms only when the surrounding gum or bone becomes inflamed or infected.
Common Reasons for Sudden Tooth Cracking
The sudden appearance of a tooth crack is often the result of cumulative stress on the tooth structure. One frequent cause is bruxism, or chronic teeth grinding and clenching, which places extreme and uneven force on the teeth. This excessive force weakens the enamel and underlying dentin, leading to micro-fractures that eventually give way to a noticeable crack. The intense, non-functional pressure generated during sleep is particularly damaging.
Another major factor is the presence of large or old dental restorations, such as silver amalgam fillings. Amalgam does not bond to the tooth structure and acts like a wedge, putting outward pressure on the remaining tooth walls during chewing. Furthermore, amalgam expands and contracts at a different rate than natural tooth material, causing thermal stress and micro-fractures over time. Simple trauma, like biting down unexpectedly on a hard object such as a popcorn kernel or ice cube, can also deliver a single, high-impact force that exceeds the tooth’s fracture resistance.
Sudden and extreme temperature changes, known as thermal shock, can also contribute to cracking, especially in teeth with large restorations. Rapidly switching from a hot beverage to an ice-cold one causes swift expansion and contraction of the enamel and any filling material. This creates internal stress, leading to the propagation of existing micro-cracks. This repeated cycle of thermal stress can ultimately cause a more significant, sudden fracture.
Immediate Action and Professional Treatment Options
If you suspect you have a cracked tooth, the most immediate step is to contact a dental professional right away. Until your appointment, you must avoid chewing on the side of the mouth where the crack is located to prevent the fracture from spreading deeper. Rinsing your mouth with warm water can help keep the area clean, and applying a cold compress to the outside of the cheek can minimize any potential swelling. Taking an over-the-counter pain reliever can help manage discomfort, but this should not delay seeking professional treatment.
A dentist will assess the crack’s severity and location to determine the appropriate treatment. For minor craze lines or very superficial cracks, a simple procedure like dental bonding, which uses a tooth-colored resin to fill the defect, may be sufficient to seal the tooth and reduce sensitivity. If the fracture is deeper but has not extended into the nerve tissue, the tooth typically requires a dental crown, which fully encases the tooth structure. The crown acts like a protective helmet, holding the weakened tooth together, distributing chewing forces evenly, and preventing the crack from worsening.
When the fracture extends into the inner pulp, causing inflammation or infection, a root canal procedure becomes necessary before the tooth can be crowned. During a root canal, the infected pulp tissue is removed, and the inner chamber is disinfected and sealed to save the tooth. A crown is then placed to restore the tooth’s structural integrity, as root canal treated teeth are more susceptible to fracture. In the most severe cases, such as non-repairable vertical root fractures or split teeth, extraction may be the only viable option to prevent infection from spreading to the surrounding bone and gums.