A dead tooth, clinically known as pulp necrosis, occurs when the soft tissue within the tooth’s center—the dental pulp—loses its vitality. This pulp contains the blood vessels, nerves, and connective tissue that keep the tooth alive and healthy, extending from the crown down to the root tips. When this tissue dies, the tooth is no longer considered a living structure, but this does not mean it is free from trouble or pain. Despite the nerve being dead, a necrotic tooth can cause significant pain. The dead tissue becomes a breeding ground for bacteria, which can then spread the infection beyond the tooth itself.
What Causes a Tooth to Die
A dead tooth results from the destruction of the dental pulp, primarily caused by an interruption of the blood supply. The two most common pathways leading to this condition are deep, untreated dental decay and physical trauma to the mouth.
Deep dental decay, or cavities, allows oral bacteria to penetrate the hard outer layers of the tooth, the enamel and dentin. If the decay is left untreated, the bacteria eventually reach the pulp chamber, causing severe inflammation known as irreversible pulpitis. This inflammation swells the tissue within the confined space of the tooth, effectively strangling the blood vessels and cutting off the necessary oxygen and nutrients, leading to tissue death.
Physical trauma, such as a sports injury or an accidental blow to the mouth, can also cause the pulp to die quickly. A sudden, forceful impact can sever the neurovascular bundle—the small blood vessels and nerves—at the tooth’s root tip. Without this blood supply, the pulp tissue dies due to a lack of circulation, sometimes occurring even without visible damage to the tooth’s exterior.
The Key Signs and Symptoms of a Dead Tooth
One of the most noticeable indicators of a necrotic tooth is a change in the tooth’s color, which typically darkens compared to the adjacent teeth. This discoloration is often a grey, yellow, or dark brown hue, caused by the breakdown of blood components, similar to a bruise. As the red blood cells within the dead pulp decompose, the resulting byproducts seep into the surrounding dentin, permanently staining the tooth structure.
A persistent foul odor or an unpleasant taste in the mouth suggests an active infection is present. This results directly from the bacterial activity and the breakdown of necrotic tissue within the infected pulp chamber. Sometimes, a small, pimple-like bump, called a fistula, may appear on the gums near the affected tooth, which is a channel allowing the internal infection to drain into the mouth.
The pain associated with a dead tooth can range from a dull ache to sensitivity when chewing. In the initial stages, as the pulp is dying, a person may experience intense, throbbing pain. However, this pain can temporarily disappear once the nerve is fully necrotic. This temporary cessation of pain is a misleading sign, indicating the death of the sensory tissue, and is frequently followed by a return of pain due to the spread of infection.
Why a Dead Tooth Can Cause Severe Pain
The severe pain experienced with a dead tooth does not originate from the nerve tissue inside the tooth itself, since that tissue is non-vital. Instead, the chronic discomfort is a direct consequence of the resulting bacterial infection that spreads beyond the root tip. The dead pulp tissue provides an ideal, protected environment for bacteria to multiply unchecked within the root canal system.
These bacteria and their byproducts travel through the apex of the root and begin to infect the surrounding jawbone and the periodontal ligament. This invasion leads to the formation of a periapical abscess, a pus-filled pocket of infection at the very tip of the tooth root. The pain is primarily caused by the immense pressure created by the accumulating pus and inflammatory fluid within the confined space of the jawbone.
The pressure from this growing abscess irritates the highly sensitive nerves within the surrounding ligament and bone tissue, leading to a constant, throbbing pain. This pain is often exacerbated by biting or applying pressure. If the infection is not contained, it can cause localized swelling in the gums, face, or neck.
Necessary Treatment Options
Treating a dead tooth is necessary to eliminate the bacterial infection and prevent it from spreading, which can lead to systemic health issues. The most common intervention to save the tooth is Root Canal Therapy (RCT).
This procedure involves creating a small opening in the tooth to access the infected pulp chamber and thoroughly remove all the necrotic tissue, bacteria, and debris from the internal root canal system. The cleaned and disinfected canals are then filled with a biocompatible material and sealed to prevent future bacterial reinfection. Following the root canal, the tooth is often restored with a crown to protect the now more brittle structure from fracture, allowing it to function normally.
If the tooth is too structurally compromised, or if the infection has severely damaged the supporting bone, extraction may be the only viable treatment option. Extraction removes the entire source of infection, though the missing tooth will need to be replaced with a bridge or an implant to maintain proper chewing function and prevent the adjacent teeth from shifting. Immediate consultation with a dental professional is necessary, as an untreated dental abscess can spread, potentially leading to widespread infections like cellulitis or, in rare cases, life-threatening sepsis.