A cavity represents damage to the hard surface of a tooth, caused by acids from mouth bacteria. Unlike other bodily injuries, a cavity will not heal on its own and will worsen if left unaddressed.
Progression of Tooth Decay
Tooth decay begins when plaque, a sticky film of bacteria, forms on the tooth surface and produces acids from sugars in food. These acids attack the outermost layer of the tooth, the enamel, leading to demineralization. This initial stage may appear as white or brown spots on the tooth and often presents without pain or visible holes.
If demineralization continues, the enamel begins to break down, forming a small hole. Once the decay penetrates through the enamel, it reaches the softer layer beneath, called the dentin.
As decay continues through the dentin, it moves towards the innermost part of the tooth, the pulp. This central chamber contains nerves, blood vessels, and connective tissue. Once the decay reaches the pulp, the tooth’s living tissue becomes exposed to bacteria and acid, leading to more significant issues.
Localized Effects on the Tooth
When a cavity first forms in the enamel, it often causes no immediate discomfort. As the decay breaches the enamel and advances into the dentin, individuals may begin to experience tooth sensitivity. This sensitivity commonly manifests as a mild to sharp pain when consuming hot, cold, or sweet foods and drinks.
As the cavity deepens further into the tooth structure, the mild sensitivity can escalate to a persistent toothache. This pain might range from a dull ache to a sharp, throbbing sensation that occurs spontaneously or when biting down. Visible signs of decay can also become apparent, such as brown, black, or white staining on the tooth surface, along with the formation of holes or pits.
When the bacterial infection reaches the pulp, it can cause inflammation. The pulp tissue swells, leading to increased pain. This stage often presents as severe, continuous pain, even without external triggers. Without treatment, the pulp tissue can die, and the infection can spread beyond the tooth’s root.
Wider Health Implications
An untreated cavity that reaches the tooth’s pulp can lead to a severe bacterial infection, forming a dental abscess. This is a pocket of pus that typically develops at the tip of the tooth root, within the surrounding bone, or in the gums. Symptoms of an abscess include intense pain, swelling in the face or jaw, and sometimes fever. The swelling can extend to the lymph nodes in the neck.
The infection from a dental abscess can spread. Bacteria can invade the jawbone, potentially weakening its structure and leading to bone loss around the affected tooth. The infection can spread to other teeth or into the soft tissues of the mouth, causing conditions like cellulitis, a serious bacterial skin infection.
In rare but severe cases, the bacteria from a dental abscess can enter the bloodstream, leading to systemic infections like sepsis, a life-threatening condition where the body’s response to infection damages its own tissues and organs. Infection can also spread to distant parts of the body, including the brain, potentially causing a brain abscess or meningitis, or even affecting the heart. Ultimately, extensive structural damage from decay or the progression of infection often necessitates the extraction of the affected tooth, resulting in tooth loss.
Cost and Complexity of Treatment
Delaying treatment for a cavity can significantly increase both the complexity and financial burden of dental care. An early-stage cavity, confined to the enamel or outer dentin, can be treated with a simple, inexpensive dental filling. This procedure involves removing the decayed portion and restoring the tooth.
If the cavity is left untreated and infects the pulp, the required procedure escalates to a root canal therapy. This involves removing the infected pulp, cleaning, shaping, and sealing it. A root canal is more invasive, and expensive than a routine filling. After a root canal, the tooth often requires a dental crown to protect its weakened structure, adding further cost.
In the most severe cases, when the tooth is too damaged by decay or infection to be saved, extraction becomes the only option. Tooth extraction incurs its own cost, but replacing a missing tooth with options like a dental implant or a bridge is more complex and expensive than saving the natural tooth, potentially costing thousands of dollars. Early intervention with a filling is consistently the most straightforward and economical approach to managing tooth decay.