Troubled modern Chinese oral health main seven big problems, including dental caries, plaque and tartar, bleeding gums, teeth, sensitive nature teeth are white and tone.

困扰现代中国人口腔健康主要有七大问题，包括龋齿，牙石，牙菌斑，牙龈出血，牙本质敏感，牙齿不洁白和口气。

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Scaling may be uncomfortable, especially if your gums are already sensitive or you have extensive plaque and tartar buildup.

CNN: Gingivitis