Bone grafts, sinus lift
Bone graft surgery is needed if the alveolar ridge is partially or totally lost. The substitution of bone can be made using different materials: own bone, human bone, bovine bone and synthetic bone. They are available as granulates and blocks in different sizes. The gold standard of bone grafting is the own bone of the patients. This type of bone grafting gives the best results and it is the cheapest, but the disadvantage of this method is the operation both at the donor and recipient site. Therefore other methods are more popular. To facilitate the integration of the graft, special proteins can be used.
Sinus lift is a special case of bone grafting. This bone grafting procedure creates more bone mass at the bottom of maxillary sinus contributing to the stability of the implant. By using this method implants can be placed into the molar molar area.
The healing of the bone around the implant varies depending on the quality of bone. It takes 2-3 months on average in the lower jaw and 4-6 months in the upper jaw. The initial stability of the implant is decreasing during the first two weeks following implantation because the osteoclastic activity (bone resorption) is more intense than the osteoblastic activity (bone building). After this two week period the process is the opposite, faster osteoblastic activity, slower osteoclastic activity. In the final third of the healing process the unorganic hard bone minerals will integrate into the bone.
Different techniques of bone grafting
If the patient does not need bone harvesting extraorally, there is no need for general anaesthesia. If that is needed the operation will be carried out under general anaesthesia, requiring at least an overnight hospitalisation. The typical donor site is the anterior iliac crest (hip bone). The harvested bone will be stabilised by screws at the recipient site. Though the cells of the donor bone block will lose vitality due to lack of circulation, the bone structure functioning as a scaffold enhances the integration of the own bone.
Regardless of the method of anaesthesia the surgical treatment is completed without causing pain for the patient. In both cases after the operation the area can be sore and swollen which can be easily controlled by painkillers. Sometimes a few days of sick leave could be indicated. The size of the grafted bone is slightly reduced during the healing period by bone transformation. Ultimately, the graft becomes identical in structure to the surrounding recipient area.
The treatment of numerous patients are rejected by clinics with less experience in bone grafting. The reason behind that is likely due to the thin bucco-linqual aveolar processus (bone ridge). Patient with this type of problem can be treated using ridge splitting, sandwich bone grafting and implant setting or with lateral augmentation and gingivoplasty.
After a six month healing period the implants can be inserted into the grafted site. The final integration of the implants takes a further four month.