Indications for dental implants (1), Sufficient alveolar bone volume (both height and width) at the site of missing teeth in the mouth. (2) The gap between the maxillary and mandibular teeth should not be less than 0.5 centimeters during occlusion. (3), The patient has no major systemic diseases such as diabetes, kidney disease, heart disease and coagulation disorders. Zheng Xiang, Stomatology Center, Henan Provincial People’s Hospital (4), no serious periodontal disease. (need to be treated by stomatologists after getting better)