Behind every smile, the strength and health of your teeth often depend on their internal structure. Among them, dentin, as an important tooth tissue, plays a major role in supporting teeth. The composition, characteristics and functions of dentin in daily life are undoubtedly things that everyone should have a deep understanding of when maintaining oral health.
Dentin is composed of approximately 45% inorganic minerals (mainly hydroxyapatite), 33% organic matter, and 22% water.
Dentin is yellow in color, which makes its appearance have a significant impact on tooth color because of the transparency of enamel. Although dentin is less mineralized than enamel and is relatively fragile, its elastic properties protect enamel from breakage. The hardness of dentin is about 3 on the Mohs scale, and the pressure resistance and elasticity of teeth make it an important part of supporting teeth.
Dentin formation begins early in tooth development, a process called dentinogenesis. Dentin is produced by odontoblasts within the dental pulp, which secrete an organic matrix called predentin, which is then further mineralized to form dentin. This process does not stop after tooth development is complete. As we age, dentin will continue to form to repair damage to the teeth, such as dentinogenesis caused by tooth decay or wear.
Dentin is made up of tiny channels called dentinal tubules that extend outward from the pulp of the tooth, throughout the dentin, and connect to the edges of the enamel, or cementum. The shape of the dentinal tubules is like an S shape. As the distance from the dental pulp increases, its diameter gradually becomes smaller, and there are odontoblast cell processes and dentin fluid inside the tubules.
Dentin is somewhat permeable to water due to dentinal tubules, which may also increase the perception of pain and the rate of tooth cavity development.
Because of the structure of dentin, dentin can respond quickly when teeth are exposed to cavities or other external stimuli. This reaction is called the formation of second dentin, which usually occurs after the tooth root is completely formed. It not only acts as a barrier for the tooth against external stimuli, but also promotes tooth health.
Dentin can be divided into three types: primary dentin, secondary dentin and inert dentin. Primary dentin is the main component of teeth, while secondary dentin gradually forms with age after the tooth root is fully formed. Inert dentin is rapidly formed when the tooth is exposed to external stimulation, such as tooth decay or wear and tear.
In-depth study of the structure of dentin can help us understand the maintenance of dental health and effective strategies to prevent and treat dental disease.
As we age or due to the effects of tooth decay, dentin may develop lesions such as dentin sclerosis. In this condition, calcification occurs in the dentinal tubules, which impairs the tooth's sensory function, causing pain and sensitivity.
In general, dentin is an amazing tissue that continuously supports our teeth through its structure and function and makes it less likely to break during daily use. So, how should we better protect this tissue to maintain dental health?