Enamel is the hard outer tooth layer.
The cavity gets larger by entering the softer second tooth layer, the dentin.
Does decay affect the dentin?
Decay spreads quickly when it reaches the dentin.
The decay must be removed at this time because it'll soon reach the sensitive tooth pulp.
If this happens, there'll be death of the pulp, pain and infection into the jaw-bone surrounding the tooth.
The tooth might have to be removed if this happens.
How can I prevent this?
It's absolutely necessary to visit your dentist twice a year for dental check up to prevent infection and loss of teeth.
那就肯定要一年去看两次牙医， 进行检查， 预防感染， 也预防牙齿脱落。
X-rays are a very important Part of a dental examination.
X-rays are needed to find decay that's hidden from sight.
What type of X-rays do you usually take, Doctor?
I usually take two different kinds of X-rays when I examine a patient.
Periapical X-rays are needed to be able to examine the roots of teeth.
It also is needed to examine the surrounding tissues for signs of periodontal disease, impacted teeth, infections and cysts.
Does this X-ray find the cavities?
This type of X-ray is not always effective for finding caries.
Cavity disclosing (bite-wing) X-rays are needed to supplement the periapical X-rays so that tooth decay can be diagnosed accurately.