Carious teeth, commonly known as tooth decay or cavities, are areas of permanent damage to the tooth surface. These damaged areas can develop into tiny holes or pits over time.
What Are Carious Teeth?
Carious teeth are the breakdown of teeth due to acids produced by bacteria. This process leads to the formation of cavities, which are holes that can vary in color from yellow to black. The tooth structure consists of three main layers: the outermost enamel, the hardest substance in the human body; dentin, a softer, yellowish layer beneath the enamel; and the innermost pulp, containing nerves and blood vessels.
When decay begins, it initially affects the enamel. If left untreated, the decay progresses through the dentin and can eventually reach the pulp, leading to potential infection.
Causes and Development
Carious teeth develop from the interaction of bacteria, carbohydrates, and time on the tooth surface. Oral bacteria, notably Streptococcus mutans and Lactobacilli, colonize on the tooth surface by adhering to a protein film called the pellicle. This colonization forms a sticky film known as dental plaque.
These bacteria metabolize sugars and starches from food and drinks, producing acids as a byproduct. These acids then attack the tooth enamel, causing it to lose minerals in a process called demineralization. While saliva and fluoride can help remineralize the enamel, repeated acid attacks can lead to a net mineral loss, weakening the tooth structure and forming a cavity.
Risk factors include poor oral hygiene, which allows plaque to accumulate, and a diet high in sweets and refined carbohydrates. Dry mouth, also known as xerostomia, can also increase risk because saliva helps wash away food particles and neutralize acids.
Recognizing and Diagnosing Carious Teeth
Recognizing the signs of carious teeth can help in early intervention. Common symptoms include tooth sensitivity to hot, cold, or sweet substances, and toothache, which can range from mild discomfort to sharp, persistent pain. Visible indications may include a chalky white spot on the enamel, which can later turn brown or black, and eventually a noticeable hole or pit. In advanced cases, bad breath and foul tastes may also be present.
Regular dental check-ups are important for early detection, even before symptoms become apparent. Dentists diagnose cavities through a combination of methods, including a visual examination of the tooth surface where a dental probe may be used to check for soft spots. Dental X-rays are also frequently used, as they can reveal cavities not yet visible during a clinical examination, particularly those between teeth or under existing fillings.
Treatment and Prevention
Treatment for carious teeth varies depending on the severity of the decay. For early decay where only the enamel is affected, fluoride treatments can help remineralize the tooth structure and sometimes reverse the cavity. Once a cavity has formed, fillings, also known as restorations, are the primary treatment. The decayed portion of the tooth is removed, and the space is filled with materials like composite resin or amalgam.
If the decay is extensive or has weakened the tooth significantly, a dental crown may be recommended to cover and protect the tooth. When decay reaches the pulp, a root canal procedure is performed to remove the infected pulp, clean the canals, and seal the tooth, aiming to save it from extraction. In severe cases where the tooth cannot be restored, extraction may be necessary.
Preventing carious teeth involves consistent oral hygiene practices and dietary modifications. Thorough brushing at least twice a day with fluoride toothpaste and daily flossing helps remove plaque and food particles. Limiting sugary and acidic foods and drinks is also important, as this reduces acid attacks on enamel. Regular dental check-ups allow for early detection and professional cleanings, and dental sealants can be applied to the chewing surfaces of back teeth to provide a protective barrier against decay.