Itching between the gaps in the teeth may be chronic gingivitis, acute periapical periodontitis, cryptocleidosis and so on. 1. Chronic gingivitis: chronic gingivitis, due to plaque, calculus stimulation, will make the teeth between the gap itching, swelling, discomfort, bad breath. 2. Acute periapical gingivitis: In acute periapical gingivitis, there will be itching, discomfort, numbness, and floating sensation between the gaps of the teeth. 3. Hidradenitis suppurativa: Hidradenitis suppurativa may cause itching between the teeth and discomfort of biting for a long time, or severe pain when biting on a special part of the tooth. Itchy teeth between the gap, there may be other reasons, it is recommended to go to the hospital in a timely manner, after professional examination, to determine the cause of the timely treatment, so as not to delay the condition.