Effects of maxillary sinus floor elevation surgery on maxillary sinus physiology

In a prospective study, the effects of elevation surgery of the maxillary sinus floor on maxillary sinus physiology were assessed. Seventeen consecutive patients without preoperative anamnestic, clinical and radiological signs of maxillary sinusitis underwent sinus floor elevation surgery with iliac crest bone grafts. All patients were subjected to unilateral endoscopic examination of the maxillary sinus, taking of a biopsy specimen from the sinus floor mucosa, and collection of a sinus lavage-fluid aspirate. This triad of evaluations was performed immediately preceding the elevation procedure, and 3 months (at implant insertion) and 9 months (at uncovering of implants) postoperatively. All procedures were performed under general anesthesia. Preoperatively, three out of 17 patients showed pre-existing mucosal pathology endoscopically, while the 3- and 9-month results revealed the presence of mucosal pathology in four and two patients, respectively. The 3-month microbiological evaluation showed a significant increase in cultures with bacterial growth, while the 9-month culture results were comparable to the preoperative status of the maxillary sinus. Morphologically, neither fibrosis nor an altered inflammatory response or thickening of the epithelium and lamina propria was observed postoperatively. The number of goblet cells in the epithelial layer was increased. From this study it is concluded that the effect of maxillary sinus floor elevation surgery with autogenous bone grafts does not appear to have clinical consequences in patients without signs of pre-existing maxillary sinusitis

Maxillary bone grafting for insertion of endosseous implants: results after 12-124 months

Insertion of endosseous implants in the atrophic maxilla is often complicated because of lack of supporting bone. Augmentation of the floor of the maxillary sinus with autogenous bone graft has been proven to be a reliable treatment modality, at least in the short term. The long-term clinical and radiographic outcome with regard to the grafts, the implants and satisfaction of the patients with their implant-supported overdenture was studied in 99 patients. The sinus floor was augmented with bone grafts derived from the iliac crest (83 subjects, 162 sinuses, 353 implants), the mandibular symphysis (14, 18, 37), or the maxillary tuberosity (2, 2, 2). Before implant installation, the width and height of the alveolar crest were increased in a first stage procedure in 74 patients, while in the other 25 patients augmentation and implant installation could be performed simultaneously (width and height of the alveolar crest >5 mm). Perforation of the sinus membrane occurred in 47 cases, which did not predispose to the development of sinusitis. Loss of bone particles and sequestration were observed in one (diabetic) patient only, in whom a dehiscence of the oral mucosa occurred. A second augmentation procedure was successful in this patient. Symptoms of transient sinusitis were observed in 3 patients. These symptoms were successfully treated with decongestants and antibiotics. 2 other patients developed a purulent sinusitis which resolved after a nasal antrostomy. In all cases, the bone volume was sufficient for implant insertion. 32 of 392 inserted Branemark implants (8.2%) were lost during the follow-up. After the healing period of the bone grafts, no sinus pathology was observed. The patients received implant-supported overdentures (72 patients) or fixed bridges (27 patients). Overall, the patients were very satisfied with the prosthetic construction. We conclude that bone grafting of the floor of the maxillary sinus floor with autogenous bone for the insertion of implants is a reliable treatment modality with good long-term results