A tongue with teeth marks and cracks in the tongue may be caused by congenital dysplasia, tongue diseases and other conditions. 1. Congenital dysplasia: tongue with teeth marks and cracks in the tongue may be fissured tongue, which belongs to congenital tongue dysplasia, mostly related to autosomal dominant inheritance, but may also be caused by tongue muscle dysplasia. If there is no obvious discomfort, no special treatment is needed. 2. Tongue diseases: when there is chronic inflammation or ulceration at the edge of tongue tissue, it can make the whole tongue tissue edematous and enlarged. However, because the tongue is in the inherent oral cavity, the space is relatively fixed, so the teeth friction will make the tongue appear teeth marks. Note that the tongue with teeth marks cracks in the tongue may also be caused by other reasons, so this situation should be promptly consulted to find out the specific cause and treatment, so as not to delay the condition.