Many of us were warned as children: "Don't eat candy, or bugs will eat your teeth while you sleep!" But are teeth truly "eaten" by bugs?
Hou Benxiang, Director of the Department of Endodontics at Beijing Stomatological Hospital (affiliated with Capital Medical University) and Deputy Secretary-General of the Chinese Stomatological Association, explains that teeth consist of two parts: the crown and the root. The junction between the crown and root is called the cervical region.The outermost layer of the crown is enamel, the hardest substance in the human body, which surrounds the dentin beneath. At the core lies the pulp, a soft tissue containing nerves and blood vessels.The hard enamel on healthy teeth possesses strong resistance to acid and alkali corrosion. However, due to the acid-producing activity of bacteria residing on the tooth surface, erosion occurs, damaging the outer hard structure and forming "cavities."Take consuming sweets as an example: microorganisms in the mouth can use sucrose to synthesize polysaccharides, which in turn form a highly viscous bacterial film (dental plaque). This plaque adheres to tooth surfaces and is difficult to remove. Bacteria can multiply rapidly, producing organic acids and other substances that damage teeth.
The development of dental caries is a gradual process. Early-stage cavities often present no specific symptoms, merely appearing as irregular yellowish-brown spots on the enamel surface, which are frequently overlooked. As decay progresses deeper into the dentin layer, noticeable black holes may become visible on the tooth surface.Typically, patients experience pain when consuming sugary foods, which subsides after rinsing. If decay advances deeper into the dentin or approaches the pulp, sensitivity to hot and cold stimuli may occur.When decay penetrates deep into the dentin, food debris becomes trapped within the cavity, allowing bacteria to proliferate rapidly. As the cavity approaches the pulp chamber, bacteria and their toxins can easily infiltrate the pulp tissue, causing intense pain. This may lead to pulpitis, apical periodontitis, and ultimately tooth loss.
The earlier cavities are treated, the more our natural teeth can be preserved. Preventing decay before it occurs is even more effective. Four factors are necessary for cavities: teeth, food, bacteria, and time. The longer food remains on the tooth surface, the more bacteria can erode the tooth.To counter this process, we can reduce the time bacteria remain in the mouth by brushing properly after every meal.
Oral hygiene should begin around 6 months of age, using a finger-sleeve toothbrush or damp gauze. When primary molars erupt, use a swallowable toothpaste. After age 3, consider switching to a low-fluoride toothpaste.At 3.5 years old, children can receive pit and fissure sealants for their primary molars. Sealants should also be applied to the first molars (6-7 years old) and second molars (11-12 years old) once they fully erupt. Children should ideally use child-sized toothbrushes. For thorough cleaning, the surfaces where teeth meet must not be overlooked. Experts recommend that adults use dental floss to remove food debris and soft plaque from between teeth before brushing.Fluoride inhibits the growth of cavity-causing bacteria, reduces acid formation within plaque, lowers tooth acid solubility, and promotes remineralization. Therefore, Hou Benxiang recommends using fluoride toothpaste to enhance teeth's resistance to decay.