I、 Symptoms and harms of caries
At the begining of caries, there is no toothache, and it can only be found by dentists. As it develops, the hole is becoming deeper, and teeth ache when eating cold, hot, sour and sweet food. Sometimes even the food entering the hole can cause toothache. Generally speaking, the deeper the hole is, and the nearer to the tooth marrow, the more obvious the toothache is.
Caries should be treated at the beginning, otherwise the hole would become eroded and deeper. When the microbe in the hole and the toxin it produces reach tooth marrow, the tooth marrow will inflame which will further cause periodontitis. If the inflammation develops, it may cause jaw and face to inflamme or other serious diseases. Therefore, the small holes on teeth may cause serious damages and must be treated in time.

II、 How to prevent and treat caries?
1． Brush teeth in the morning and evening or after meals and gargle after meals to clean the remains of food and microbe in mouth and between teeth. Toothpaste containing fluorin is helpful to prevent caries.
2． Pay attention to the food and stomatological sanitation of children. Their food should be diversified and adequate hard or tough food can advance the development of their jaws and teeth. They can't sleep with candy in mouth or without brushing teeth after eating sweet stuff for candy may become acid and decay teeth to form caries.
3． Block the teeth grooves with resinous materials for children between 6 and 12 after permanent teeth grow to prevent food chipping and microbe entering teeth so that to prevent caries.
4． Treat malpositioned wisdom teeth and teeth stuffed with food. Discard inadequate false teeth and tooth covers in time.
5． Make stomatological check every half year of each year.
6． Cure caries in time. If the hole is not deep, wipe off the decayed teeth and fill the tooth with adequate materials to renew its form and functions. If the hole is deep, cure it according to different situation. For tooth marrow inflammation or root inflammation cause by caries, clean the microbe infection in tooth marrow or around the root to keep the tooth. For the root can't be saved, remove the root and fix a false tooth.

III、 What is gum inflammation and what are the causes?
At the beginning of gum inflammation, the border of gusm become dark, swoln, and gums will bleed on slight stimulation. Sometimes, the gums itch, swell, become numble and uncomfortable. After some time, gums become incrassate obese and form "hyperplastic gum inflammation".
Causes for gum inflammation include:
　　①Stimulation of tooth stone：food remains between teeth combining with casted cells, dope in saliva, and stomatological germina form soft tartar on teeth and roots. Tartar and calcium in saliva deposit and become hard filemot tooth stones which can't be removed by brushing teeth and may stimulate gums to cause gum inflammation.
　　②Stuffing of food. If the gaps between teeth are wide or teeth are not ranged in order, food may be stuffed in the gaps. Zymotic food expand and press gums to cause inflammation, swelling, and aches.
　　③Improper false teeth: tooth cover made of stimulating metal, improper tooth cover, tooth cover having food inside can all stimulate gums and cause the gum inflammation.
　　④Incorrect fillings: too much fillings that fill caries may press and stimulate gums for long time and cause partial gum inflammation.

IV、 What is root therapy？
Root therapy is the best method curing tooth marrow diseases and root diseases by eliminating the inflammed tooth marrow and necrotic subsatnce in roots, sterilizing and filling the roots to removing the stimulation and prevent diseases or accelerate the healing of infected roots. With the development of this therapy, teeth that need to be removed before can be kept now.

V、 Basic principles and procedures of root therapy.
Normal root therapy include the following 3 procedures:
1． Clear roots：remove microbe and remained tooth marrow in roots.
2． Shape roots：form a smooth cone-shaped root pipe whose diameter is biggest at the mouth and whose diameter is smallest 1mm from the top end.
3． Fill roots：use compatible and unsolvable materials to fill roots.

VI、 Why "cleaning teeth" periodically？
"Cleaning teeth" is a basic method to keep teeth healthy and cure teeth diseases. Though we brush teeth everyday, bacteria spots can't be removed. After long-period calcifying with the minerals in saliva, they become tooth stones clinging to teeth, esp. at the edge of gums. Tooth stones will stimulate gums and cause inflammation. And then there will be halitosis, teeth falling, gum acheing, and patients can't eat cold, hot and acid food. Therefore we need to clean teeth periodically to eliminate the causes of tooth diseases.
People who have more tooth stones may feel uncomfortable after cleaning teeth, such as dare not eat cold or hot food, air leaking when speaking and movable teeth which are normal phenomena and will disappear after some time.
Cleaning teeth is simple but profitable. We should keep washing teeth periodically to take care of our teeth.

before cleaning		after cleaning

before cleaning		after cleaning