How a dentist fixes a cracked tooth depends entirely on how deep and where the crack runs. A hairline surface crack might need nothing more than monitoring, while a crack that reaches the root could mean losing the tooth. Most cracked teeth fall somewhere in between and can be saved with bonding, a crown, or a root canal followed by a crown.
Not All Cracks Are the Same
The American Association of Endodontists classifies tooth cracks into five types, and knowing which one you have is the single biggest factor in what happens next.
- Craze lines are tiny, shallow cracks in the outer enamel. Almost every adult has them. They don’t hurt, don’t grow, and don’t need treatment.
- Fractured cusp means a piece of the chewing surface has broken off, usually around a filling. It rarely affects the nerve and is typically straightforward to repair.
- Cracked tooth is a crack that runs vertically from the chewing surface down toward the root but hasn’t yet split the tooth into separate pieces. This is the most common type that brings people to the dentist with pain.
- Split tooth is what happens when a cracked tooth goes untreated long enough for the crack to divide the tooth into distinct segments. Saving the entire tooth at this stage is usually not possible.
- Vertical root fracture starts in the root and works upward. These cracks often produce minimal symptoms for a long time, which makes them hard to catch early. Extraction is the typical outcome.
These categories exist on a spectrum. A crack that’s manageable today can worsen over months or years, which is why early treatment matters.
How Dentists Find the Crack
Cracks are notoriously difficult to see, even on X-rays. Your dentist will likely use several tools together to locate the problem. The most informative is transillumination: shining a bright fiberoptic light through the tooth. Light travels through solid tooth structure but stops at a crack, creating a visible dark line where the fracture sits. It’s painless and takes seconds.
Your dentist may also ask you to bite down on a small stick or rubber instrument, applying pressure to individual cusps one at a time. A sharp, fleeting pain when you release the bite is a classic sign of a crack. Periodontal probing (measuring the pocket depth around the tooth with a thin instrument) can reveal an isolated deep pocket right where a crack meets the gum line.
For deeper or harder-to-find cracks, a 3D scan called cone beam computed tomography can show fractures that traditional X-rays miss, especially cracks running along the root. Even so, both CBCT and standard imaging have moderate sensitivity for detecting cracks, catching them roughly 59% of the time. High specificity (around 90% for CBCT) means that when the scan does show a crack, it’s almost certainly real. Many dentists with cracked teeth are asymptomatic, so sometimes the diagnosis comes from a routine exam rather than a pain complaint.
Bonding for Minor Cracks
When a crack is small, shallow, and limited to the outer structure of the tooth, dental bonding is often all that’s needed. Your dentist roughens the enamel surface slightly, applies a tooth-colored resin, and hardens it with a curing light. The whole process takes about 30 to 60 minutes per tooth, requires no anesthesia for most people, and can be done in a single visit.
Bonding works well for fractured cusps, small chips, and cracks that haven’t reached the inner layer of the tooth (the dentin). It seals the crack to stop bacteria from getting in and restores the tooth’s shape. The tradeoff is durability: bonding material isn’t as strong as a crown and may need to be replaced after several years, especially on a back tooth that takes heavy chewing force.
Crowns for Deeper Cracks
For a true cracked tooth, where the fracture extends into the dentin but hasn’t reached the nerve, a full-coverage crown is the standard fix. The crown caps the entire visible portion of the tooth, holding the cracked pieces together and preventing the crack from spreading further.
The process typically takes two appointments. At the first, your dentist reshapes the tooth to make room for the crown and takes an impression or digital scan. You’ll wear a temporary crown for one to three weeks while the permanent one is fabricated. At the second visit, the permanent crown is cemented in place. Some offices with same-day milling technology can complete the entire process in one appointment.
Research strongly supports crowns over simpler fillings for cracked teeth. A systematic review and meta-analysis found that cracked teeth treated with direct restorations (fillings without full coverage) had a 3.2 times higher risk of pulp complications and an 8.1 times higher risk of eventually needing extraction compared to those that received crowns. Costs vary by location and material, but a crown in a mid-range U.S. market typically runs between $700 and $1,300 before insurance.
When a Root Canal Is Necessary
If the crack has reached the pulp, the soft tissue inside the tooth that contains nerves and blood vessels, a root canal is needed before a crown can be placed. You’ll know the crack has likely gone this deep if you experience lingering pain after eating or drinking something hot or cold, spontaneous throbbing, or swelling near the gum line.
During a root canal, the dentist or endodontist removes the inflamed or infected pulp, cleans and shapes the inside of the root canals, and fills them with a sealing material. A crown is then placed over the tooth. Cracked teeth that receive a root canal followed by a full crown have survival rates between 83% and 91% at one to four years. Without a crown after root canal treatment, the risk of extraction jumps by more than 11 times.
Not every cracked tooth qualifies for a root canal, though. If the crack extends across the floor of the pulp chamber or splits the tooth into separate segments, saving the tooth becomes unreliable. Endodontists use magnification to assess how far the crack reaches internally before deciding whether treatment is worth pursuing.
Extraction and Replacement
Vertical root fractures and fully split teeth generally can’t be saved. In these cases, extraction is the only reliable option. The good news is that replacement can sometimes happen quickly. If the surrounding bone is in reasonable shape, a dental implant can be placed at the same appointment as the extraction. More often, though, the crack has already caused some bone loss around the root, and a bone grafting procedure is needed first. That adds several months of healing before the implant can be placed.
The full timeline from extraction to a finished implant crown is typically four to eight months, depending on whether bone grafting is required. During that time, you’ll usually have a temporary tooth option so you’re not walking around with a gap.
What Recovery Feels Like
For bonding and crown placement, recovery is minimal. Your mouth may feel sore for a few days, especially around the gum line where the work was done. Sensitivity to hot and cold is common in the first week or two after a crown is placed but usually fades as the tooth adjusts.
After a root canal, expect mild to moderate soreness for a few days. The tooth itself no longer has a nerve, so it won’t feel temperature sensitivity, but the surrounding tissues need time to calm down. Most people return to normal eating within a week. The critical thing during recovery is to avoid chewing hard foods on the treated tooth until the permanent crown is in place, since the tooth is at its most vulnerable with only a temporary restoration.
Preventing Future Cracks
If you grind or clench your teeth at night, a custom night guard is one of the most effective ways to protect against future cracks. Grinding generates enormous force on your teeth, enough to propagate existing craze lines into full cracks over time. A night guard cushions that force and distributes it more evenly. It also protects existing crowns, implants, and other dental work from damage.
Beyond a night guard, avoid chewing ice, hard candy, and unpopped popcorn kernels. These are responsible for a disproportionate number of cracked teeth. If you play contact sports, a sports mouth guard is worth the investment. And if you have large, old fillings, especially amalgam ones, ask your dentist whether a crown might be a smart preventive step. Large fillings weaken the remaining tooth structure, and a crack through a heavily filled tooth is one of the most common scenarios dentists see.