A fractured cusp is one of the most common cracked-tooth emergencies and, when assessed early, one of the most treatable. The cusp is the pointed chewing corner of a back tooth. When it breaks or shears off, the tooth can become structurally unstable and painful under biting pressure.
Although a fractured cusp does not always expose the nerve immediately, normal chewing forces place ongoing strain on the remaining tooth structure. Without timely assessment, the fracture may deepen, spread into the body of the tooth, or allow bacteria to reach deeper layers.
Within emergency dentistry, this type of damage is evaluated not just by how it feels, but by how the fracture behaves under load and whether the tooth can be stabilised safely. Early diagnosis allows appropriate protective or staged treatment to be planned before infection or irreversible damage occurs.
At Deepcar Dental, patients across Deepcar, Sheffield North, Stocksbridge, Oughtibridge, Wadsley, and Barnsley are treated under the care of Dr Ibraheem Ijaz, a GDC-registered Principal Dentist with advanced postgraduate training in restorative, digital, and emergency dentistry.
A fractured cusp may cause:
Fractured cusps typically occur due to a combination of structural weakness and mechanical stress, including:
Yes. A fractured cusp should always be assessed urgently.
Even when pain is mild, chewing forces can cause the fracture to propagate deeper into the tooth, potentially leading to nerve irritation, infection, or complete tooth fracture. Early stabilisation significantly improves the chance of saving the tooth.
The seriousness depends on how far the fracture extends:
Mild fracture
Outer enamel only; tooth structure largely intact.
Moderate fracture
Part of the cusp has broken away, exposing dentine.
Deep fracture
The fracture approaches or irritates the dental nerve.
Severe fracture
The fracture extends below the gumline or into the root, making the tooth unrestorable.
Diagnosis follows a structured clinical protocol:
Clinical examination
Assessment of fracture location, depth, and stability.
Digital X-rays
Evaluation of nerve proximity, underlying decay, and bone support.
Bite Testing
Identification of pain triggered by pressure on a specific cusp.
Transillumination
Use of focused light to detect hidden crack lines.
Magnification Assessment
Determines crack direction and likelihood of progression.
Treatment depends on the severity.
The tooth is carefully evaluated to determine:
Immediate measures are taken to prevent further damage and relieve discomfort, including:
Depending on severity, treatment may include:
Only treatments necessary to stabilise or definitively restore the tooth are recommended.
Delaying care may result in:
A fractured cusp is a structural failure and cannot heal without intervention.
Do:
Avoid:
Yes. Once dentine is exposed, bacteria can reach deeper tooth structures.
No — modern techniques and local anaesthetic make treatment comfortable.
Not always.
Shallow fractures may be repaired with a filling, but deeper fractures often benefit from a crown for long-term stability.
No. Shallow fractures may be restored with fillings, while deeper fractures benefit from crowns for long-term stability.
Early diagnosis allows stabilisation, prevents nerve damage, and maximises the chance of saving the tooth. Calm, same-day emergency care is available across Deepcar and surrounding areas.