Oral implantology is an independent and emerging branch discipline developed in 1930s. It mainly includes implant surgery, implant denture restoration, implant materials, implant mechanics and implant biology. China held the first seminar on implant dentures in Zhuhai in 1995, and established the national cooperative group on dental implant dentures. In 2002, the Professional Committee of Dental Implants of Chinese Stomatological Association was established. After more than ten years of frequent international exchanges and the introduction of advanced international implant concepts and technologies, oral implantology in China has developed rapidly and matured day by day. The development of implantology has updated the content and concept of traditional oral restoration, and implant denture has become the first choice for missing teeth restoration.
2. The concept of implantation.
Implants in a broad sense refer to artificial devices implanted in human body, such as orthopedic artificial joints, bone screws, pacemakers and so on. Oral implants include dental implants (artificial roots) and craniofacial implants, which are used to retain prosthetic eyes, ears and nose. Dental implant refers to a device designed to implant artificial materials into maxilla or mandible by surgical means to support the superstructure of denture restoration.
Three. Dental implant materials.
1952, Swedish scholar Branemark implanted titanium observation window into bone to observe its microcirculation for a long time, but he happened to find that titanium was firmly combined with bone, so he began to study titanium for dental implantation as early as the 1960s. Titanium and titanium alloys have become the most widely used and favored metals because of their good biological properties and ideal mechanical properties, so most of the products planted at present use titanium or titanium alloys.
4. Applied anatomy of mandibular implants.
Mandibular bone is dense with upper and lower cortical bones. The implant is well preserved in the early stage, and there is more bone between the two mental holes. Implantation will not damage the inferior alveolar nerve. This is a safe area for implantation. The anatomical structures that should be paid attention to in mandibular implantation are mandibular canal and mental foramen. The mandibular canal runs backward, and the closer it is to the molar, the closer it is to the lingual side. No matter the maxilla or mandible, the implant needs the bone on the labial (buccal) side of 65438±0.5mm or more, the distance between the implant and mandibular canal and adjacent teeth needs to be more than 3mm, the distance between the implant and mental foramen needs to be 2-3 mm, the root-crown ratio of the implant should be greater than 3:2, and the inclination should be less than 25-30 degrees. After the second molar, it is difficult to explore because of its backward position.
5. Applied anatomy of maxillary implant.
The anatomical structure of the maxilla is irregular, the maxilla is looser than the mandible, and its dense bone is thinner. The bone mass in the anterior tooth area, alveolar ridge and nasal floor is large and the bone is thick. There are enough bone segments between the nasal cavity and maxillary sinus in canines, which is considered as a safe area for implantation. After missing teeth, the alveolar process shrinks, and there is less bone behind the maxillary premolar, with an average height of only 5-8 mm. The bone morphology of the maxillary molar area can be confirmed by referring to the X-ray film, and it can be directly implanted. For example, the bone mass of the maxillary sinus floor is limited, which may penetrate the maxillary sinus floor, so it cannot be implanted directly, and it should be implanted after the bone mass of the maxillary sinus floor. The labial cheekbone plate of maxillary alveolar fossa is extremely thin and thicker on the palatal side, but the cheekbone plate of maxillary first molar is thickened due to temporal alveolar ridge.
The principle of intransitive verb dental implant implantation.
1. The operation is non-invasive, and the temperature of the bone bed should not exceed 47℃ when preparing the implant socket.
2. There is no pollution on the surface of dental implant.
(1) is the same as the basic aseptic principle of surgery. (2) No lipid and foreign protein pollution. If there is foreign protein, the implant will have rejection. If it is contaminated by lipids, the tissue affinity of implants will be greatly reduced. (3) There is no heterogeneous metal pollution, and the instruments in contact with the implant are all special titanium instruments, not dissimilar metal instruments.
3. Requirements of planting area. Implants should have healthy lip, cheek, tongue and palate bones, with a thickness of not less than 65438 0.5mm, an implant spacing of not less than 3mm, an implant spacing of not less than 2mm with natural adjacent teeth, an implant tip spacing of not less than 2mm, and a general implant length of not less than 8-65438 0.5mm. Implants can penetrate the sinus floor and nose floor, but they must not penetrate the mucosa, otherwise they will be infected. The immediate implant length should be greater than or equal to 12- 15mm, and should exceed the root tip of alveolar fossa. The in vitro time of autogenous iliac bone or fibula transplantation should be controlled within 40 minutes.
Seven. Complications of implantation.
1. The wound is cracked, and the suture is too tight or too loose, especially in the case of inducing infection, which is more likely to lead to local wound cracking.
2. Hemorrhage, due to large mucosal exfoliation injury or extensive submucosal exfoliation, especially insufficient postoperative compression, submucosal or subcutaneous hemorrhage is easy to occur. It is recommended to apply cold compress early after operation and hot compress later.
3. The numbness of lower lip is mostly caused by mental nerve injury during operation or direct trauma during implant implantation. The former can be recovered, and the latter should take out the implant to avoid nerve displacement and implantation.
4. Perforation of sinus mucosa. When maxilla is implanted, it is easy to penetrate maxillary sinus or nasal mucosa due to insufficient bone mass.
5. Infection, contamination of operating area or instruments and other complications can induce infection.
6. Gingivitis is caused by poor oral hygiene or incorrect cleaning methods, poor cleaning of implant abutments exposed in the oral cavity, and dental plaque attached to abutments that irritates gums.
7. Gingival hyperplasia is due to too little penetration of abutment into gum, or poor connection between abutment and bridge, resulting in poor local hygiene. Long-term chronic inflammatory stimulation can cause gingival hyperplasia.
8. Progressive marginal bone resorption mostly occurs in the bone tissue of the implant neck, which is related to gingivitis, inflammation around the implant, excessive stress concentration of the implant and long-term uncorrected mechanical fracture of the implant.
9. External injury of implant, common implant dentures are accidentally hit, which will cause slight loosening of implant in severe cases.
10. Mechanical fracture of implants, such as central screw and bridge pile screw, is mainly caused by mechanical factors or unreasonable stress distribution.
8. Criteria for successful implant denture.
1995 the standards put forward by Chinese journal of stomatology at the symposium on implant denture held in Zhuhai are:
1. Good function.
2. No numbness, pain and other discomfort.
3. Feel good about yourself.
4. There is no X-ray transmission area around the implant, the transverse bone absorption is less than 1/3, and the implant is not loose.
5. Gingivitis can be controlled.
6. No implant-related infection.
7. Do not damage the supporting tissues of adjacent teeth.
8. It's so beautiful.
9. The chewing efficiency is 70%.
10. Those who meet the above requirements have a five-year success rate of over 85% and a 10 success rate of over 80%.