Graftless sinus augmentation and growth factors, clinical results and biological perspective

Abstract

The compartment around implants under the sinus mucosal lining in the sinus floor can either be filled with various scaffolds or left to be filled with blood clot from surrounding bleeding after sinus lifting procedure. Two studies have been performed to evaluate bone formation the lifted maxillary sinus Schneiderian membrane (MSSM). The first study involves graftless sinus lifting procedure with simultaneous placement of dental implants while the second study involves sinus lifting but grafted with buccal fat pad (BFP) and concentrated growth factors (CGFs). In the first study, eighteen consecutive patients underwent 30 graftless sinus lifting procedures using the lateral window approach, with 72 dental implants. Clinical and radiological follow-up was conducted throughout six-month healing period. Biopsies of 30 cases were taken and analysed during the second-stage surgery. Fifteen biopsies were taken from the newly formed bone near the basal floor and the others from the newly formed bone near the elevated membrane. New bone consolidation in the maxillary sinus was radiologically and histologically apparent after six months of sinus augmentation, providing an average 6.14 ± 1.34 mm of bone-gain. Based on histological analysis and histomorphometric data, the consolidated bone in the augmented sinus utilising two-place biopsy samples have demonstrated 56.7% ± 11.9% to 59.9% ± 13.4% vital bone tissue. Out of the 72 implants placed, only 4 failed, indicating a 95% overall implant survival rate. In the second study, six consecutive patients underwent 10 sinus-lifting procedures, 24 dental implants. The compartment around the implants under the sinus mucosal lining in the sinus floor was filled with autologous adipose tissue from BFP and CGFs. Clinical and radiological follow up were conducted through healing period, all cases, samples were taken for biopsy during the second stage surgery. New bone consolidation in the maxillary sinus was radiologically and histologically observed within an average of 7.2 months after the sinus augmentation. According to the histomorphometric data, 62.8% ± 13.1% vital bone formation was observed. Out of the 24 implants placed, only 1 failed, indicating a 95% overall implant survival rate. These studies, based on their respective size of case series, strongly indicate that the autologous blood clot and the BFP/CGFs constitute osteogenic graft material to which osteoprogenitors can migrate, differentiate, and regenerate bone.