There is a gap in the middle of the teeth black, may be dental calculus, neighboring surface caries, pigmentation and so on.
1. Calculus: Usually brush teeth not thoroughly lead to the accumulation of food debris, etc. in the teeth, over time the formation of calculus, resulting in black teeth.
2. Neighboring surface caries: there is food blockage between adjacent teeth, and over time, neighboring surface caries will lead to darkening of the gaps between teeth.
3. Hyperpigmentation: usually like to drink strong tea, colored drinks or smoking, etc., easy to cause hyperpigmentation, resulting in black teeth over time.
Usually maintain good oral hygiene, food congestion in the teeth in time to clean out, as little as possible to smoke, drink less colored drinks, etc., can reduce the chances of black teeth. There is a gap in the middle of the teeth black, timely to the hospital, clear cause and symptomatic treatment.