Dental caries, commonly known as tooth decay or cavities, is one of the most common oral diseases affecting children and adults worldwide. The good news is that it is largely preventable and, when detected early, simple and affordable to treat. Unfortunately, many people wait until they experience severe pain before visiting a dental clinic. By then, the damage is often much greater, treatment becomes more complicated, and the costs increase significantly. ALSO READ: A happy mouth is a happy life Dental caries begins when bacteria in the mouth feed on sugars from the foods and drinks we consume. These bacteria produce acids that gradually dissolve the outer protective layer of the tooth, called enamel. At first, this process may not cause any pain. A small cavity can develop silently, making it easy to ignore. However, if left untreated, the decay continues deeper into the tooth, reaching the dentin and eventually the dental pulp, where the nerves and blood vessels are located. This is when severe pain, swelling, or infection often develops. ALSO READ: Tooth decay affects one in three children Many people believe that oral diseases are expensive to treat. In reality, early dental treatment is usually simple and affordable. A small cavity often requires only a dental filling, which restores the tooth and prevents further damage. The real expense comes from delaying treatment. As the decay progresses, more complex procedures become necessary, increasing both the cost and the time needed for treatment. ALSO READ: Are you safe from dental cavities? When tooth decay reaches the pulp, a filling is no longer enough. The tooth may require root canal treatment, a procedure that removes the infected tissue inside the tooth, disinfects the canals, and seals them to preserve the natural tooth. Although root canal treatment is an excellent way to save a damaged tooth, it is more complex and costly than treating a small cavity. If treatment is delayed even further, the tooth may become so severely damaged that it cannot be saved. In such cases, tooth extraction becomes the only option. Losing a tooth is not just a cosmetic issue. Missing teeth can make chewing difficult, affect speech, reduce self-confidence, and allow neighboring teeth to shift out of position. Replacing an extracted tooth with a denture, bridge, or dental implant can also be expensive and may not always be accessible for everyone. The message is simple: the longer you wait, the worse the problem becomes. A cavity does not heal on its own. It continues to grow until it is treated by a dental professional. Ignoring tooth pain or hoping it will disappear only increases the risk of infection, tooth loss, and higher treatment costs. Fortunately, preventing dental caries is within everyone's reach. Brush your teeth twice a day with fluoride toothpaste, clean between your teeth daily using dental floss, limit sugary foods and drinks, drink plenty of water, and visit a dental clinic regularly for check-ups; even if you are not experiencing pain. Regular dental check-ups allow problems to be detected early, before they become serious. Oral health is an important part of overall health. Healthy teeth enable us to eat comfortably, speak clearly, smile confidently, and enjoy a better quality of life. Investing a little time in prevention today can save you from pain, tooth loss, and costly treatment tomorrow. Remember, dental caries starts small, but it never stops on its own. Seek dental care as soon as you notice a problem. Early treatment protects your smile, preserves your natural teeth, and is always less expensive than treating advanced disease. Your teeth are meant to last a lifetime – take care of them before it is too late. The writer is an oral health advocate and dental student at University of Rwanda.