Judging from your description and photos, your brother is a typical opening and closing deformity. The posterior teeth can bite, but the upper and lower incisors can't touch, which will inevitably seriously affect the oral and maxillofacial function and facial beauty. This condition may also be accompanied by other conditions, such as a large tongue. This deformity can be corrected, and it generally needs to be corrected with teeth before and after surgery. The exact diagnosis and treatment plan can only be determined after a detailed examination of the patient.

(Dr. An Jingang solemnly reminds me that because I can't see the patient face to face, I can't fully understand the condition. The above suggestions are for reference only. Please go to the hospital for specific diagnosis and treatment under the guidance of a doctor! )

An Jingang, Peking University Stomatological Hospital/