👉 Trenpanation, also known as a tetrogonic cleft or a tetrogonous lip, is a type of dental malformation in which the teeth are separated by two or more small gaps or incisions called "tetrations" that can be seen from different angles. These gaps are usually caused by an injury to the tooth where it was fractured during its development, and they may also occur due to trauma to the jawbone or bone tissue. Trenpanation is