The Tooth The Tooth  | The tooth is anamazing sensoryorgan. The outside of the tooth, the enamel, isthe hardest tissue in the human body. The enamel surrounds another layerof the tooth called the dentin. The tooth pulplies in the middle of the tooth. The pulp contains blood vessels, nervefibers and other connective tissue. While the pulp has several functions,including the formation of dentin, the sensory function of teeth is quiteinteresting. The nerve fibers inside teeth are exquisitely sensitiveto stimulation when they can be activated. If you have ever had a crackedtooth or had a cavity in a tooth, you know that the message sent to thebrain by the teeth is PAIN!!!. (The existence ofa nonpainful sensory function of teeth is being debated in the currentscientific literature). However, in undamaged teeth, the sensory fibersin teeth appear to be "quiet". You may be thinking..."Wait a minute. If I touch my teeth, I feel thetouch and it doesn't hurt. So the teeth must send nonpainful signals."It is true, of course, that if you touch your teeth you feel the touch.However, the signal is NOT because you activate nerve fibers INSIDE thetooth. Rather, touching the tooth activates nerve fibers in the |
However, if the tooth is damaged bydecay or trauma, the nerve fibers inside the tooth may respond to externalstimuli and when they are, you are sure to feel pain.
Just for the record, children usually have 20 baby teeth (also called milkteeth). Adults have 32 permanent teeth. The 32 teeth in adults includethe 3rd molars, also called the wisdom teeth. In some people thewisdom teeth do not come in at all.
See the sensory function of teeth and periodontal ligament for moreinformation.
| Hearing | Smell | Taste | Touch | Vision | WorkingTogether |
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