The restoration of missing teeth is divided into traditional fixed bridges, removable dentures and dental implants. Fixed bridges are used to repair missing teeth by grinding down the healthy teeth on both sides of the missing teeth to form a crown bridge, including the porcelain bridge popular in China in the past few years, whose biggest drawback is that it is used at the expense of healthy neighboring teeth, and the scope of application is limited by objective conditions, and has been largely abandoned in developed areas. The movable dentures are fixed with mesh rings and plastic pallets, which are less aesthetic and stable, and cannot fully restore chewing efficiency, affect pronunciation and foreign body sensation, which is difficult to satisfy patients; however, the damage to the surrounding teeth is smaller than that of fixed bridges, and they are still used by people with less economic conditions. The rapidly developing artificial dental implant technology is widely accepted as the third set of teeth after the permanent teeth in the 21st century, because it does not need to damage the neighboring teeth and is almost the same as the natural teeth in terms of function and aesthetics. Dental implants are divided into delayed implantation and immediate implantation according to the timing of implantation. At present, the more common clinical application is delayed implantation, which refers to the implantation on the healthy alveolar bone 2-3 months after tooth extraction, and then the upper porcelain teeth are installed after 4-6 months of bone healing. Immediate implant placement is the simultaneous placement of implants after tooth extraction, i.e., the implants are placed immediately in the fresh extraction socket. The immediate implantation method has the following advantages: 1. it shortens the procedure and reduces the patient’s pain; 2. the width and height of the alveolar bone can be preserved, and the implant bed can be easily prepared with little damage; 3. it effectively reduces the physiological resorption of the alveolar bone, and avoids the large bone grafting or reconstruction due to the lack of bone in the implant area; 4. 4. It facilitates the placement of the implant in the ideal anatomical position, making it more in line with biomechanical requirements; 5. It is conducive to maintaining the morphology of the gingiva, which maintains the normal curvature of the gingival papilla and the soft tissue profile to obtain the ideal aesthetic effect. Not all missing teeth can be implanted immediately. Immediate implant prosthesis is mainly suitable for: single-rooted teeth; no obvious inflammation and granuloma in the apical zone of the affected tooth, no local fistula and bone destruction; sufficient soft tissue around the implant area; no obvious inflammation in the soft tissue around the implant area, no gum tear, no obvious bone defect and fracture in the alveolar bone. Immediate restoration means restoration immediately after implantation. The traditional implant system requires 4 to 6 months after implantation before fitting the teeth, but with the development of material science, biomechanics and other technologies, immediate restoration is possible, and in recent years, many scholars have shown that immediate restoration can also obtain better clinical results. Immediate restorations can significantly shorten the treatment period, and can be completed within 2 hours at the earliest, while also facilitating gingival tissue formation and quickly restoring the patient’s aesthetic and partial occlusal function. Since its inception, this technique has been well received by patients, especially those who are busy and have little time to spare. Of course, not all patients can be restored immediately. Immediate restoration of implants is mainly suitable for single anterior teeth or bicuspids, with good bone and soft tissue conditions, and requires the use of root implants with special surface treatment and good initial stability after implant placement to effectively guarantee the success rate and clinical results of immediate restoration.