What is the cause of the "black triangle" of teeth?

1. Periodontitis

Periodontitis can lead to gingival recession and alveolar bone resorption, and due to long-term poor oral hygiene, dental calculus and plaque will accumulate on the gum margins 

and between the teeth, constantly stimulating the gums, causing red and swollen gums, bad breath, loose teeth, and gums. It will also slowly shrink, exposing the root of the tooth.

2. Inadequate oral hygiene

If you do not pay attention to oral hygiene and do not develop the habit of brushing, flossing, and cleaning your teeth regularly, calculus will accumulate, 

providing an ideal surface for further accumulation and mineralization of plaque. In addition, improper use of toothpicks can also stimulate local gums and alveolar bones, causing gingival recession.

3. Irregular teeth

Tooth crowding will cause soft tartar between the teeth to be difficult to clean. Long-term inflammation of the gums will lead to gingival recession. 

After the original crowded teeth are aligned through correction, the excessively large gaps between adjacent teeth will be exposed. , resulting in a pronounced gingival black triangle.

4. Crown shape

Black triangles mostly occur in the anterior region, but rarely in the posterior region. This is because the teeth in the anterior region have relatively long, narrow, and triangular crowns, 

especially those with pointed round teeth. The position of the contact point will be very high, and the vertical distance to the alveolar crest will be elongated. So black triangles are more likely to occur.

5. Natural periodontium is different

Not everyone's periodontal is born the same, we can simply distinguish between: thin periodontal biotype and thick periodontal biotype. In thick periodontal biotype, the bone tissue is thick and dense, 

the gingival papilla is wide and flat, the periodontal has good blood supply and biological tissue memory, and the gingiva is not easy to shrink; on the contrary, in the thin periodontal biotype, 

the bone morphology is often Scallop-shaped, long and narrow gingival papilla, prone to permanent recession, so it is easier to appear black triangle after correction.

6. Age

With age, the height of gingival papilla decreases by an average of 0.012mm per year, and the incidence of black triangles also increases. (A black triangle is more likely to occur

 if you wear braces over the age of 20 than if you are under the age of 20).

7. Irregular operation

Excessive correction force can cause gingival recession and black triangles, especially for adults, so pay more attention to the principle of light force. In addition, there is a very high chance of black triangles after the extraction of the front teeth, because it is difficult for the roots to move in parallel when closing the extraction gap.