Buck teeth, also known as malocclusion, are caused by incongruent dental and craniofacial relationships, specifically including misalignment of individual teeth, abnormal arch morphology and tooth alignment, and abnormal occlusal relationships between the upper and lower arches. To determine whether it is a mild buck tooth, it can be clarified by clinical performance and auxiliary examination. 1. Judgment based on clinical performance In patients with minor buck teeth, the upper and lower incisors and upper and lower jaws protrude forward, and in a relaxed state, most of the upper and lower lips cannot be closed naturally, and the gums are partially exposed when smiling. From the frontal view, the patient has an open lip and deep nasolabial fissure; from the lateral view, the patient’s facial contour line protrudes forward at the lip, which affects not only facial aesthetics but also chewing and temporomandibular joint function. Facial observation is the most intuitive way to determine minor buck teeth. X-ray projection measurement plays an important role in the diagnosis and treatment of buck teeth. By comparing the patient’s X-ray measurement with the normal reference value, it is possible to clarify the mechanism and nature of buck teeth formation, identify bony or dental malformations; the location and severity of buck teeth; the interrelationship between maxillary and mandibular bones, between teeth and jaws, and between soft and hard tissues of the face, and determine the ideal location for orthodontic treatment. The ideal position for orthodontic treatment, etc.