New Bone Formation Following Sinus Membrane Elevation Without Bone Grafting: Histologic Findings in Humans
Jae-Jin Ahn, DDS, MS, PhD/Sung-Am Cho, DDS, MS, PhD/Gerard Byrne, DDS/Jae-Hyun Kim, DDS, MS/Hong-In Shin, DDS, PhD
Purpose: To determine whether sinus membrane elevation alone can lead to new bone formation on the maxillary sinus floor. Materials and Methods: Among patients who were to receive implant treatment, those who had 4 to 5 mm of bone height in the maxillary sinus floor (as measured radiographically) were selected as candidates for sinus membrane elevation. The lateral sinus wall was exposed through a buccal mucoperiosteal incision. The sinus membrane was elevated through a bone window, and the space underneath the membrane was filled with absorbable collagen sponge (Collaplug). In the presence of blood in the space, the collagen sponge was left to soak up the blood; in the deficiency of blood, the sponge was saturated with venous blood drawn from the brachial vein. The mucoperiosteal flap was repositioned and closed with interrupted silk sutures. The sinus was left to heal for 6 months. Core specimens of the maxillary sinus floor were obtained using a trephine bur at 6 months after sinus elevation in patients treated between January 2006 and June 2009. The trephined sites were used for implant placement. The biopsy specimens were analyzed histologically to identify the presence and amount of new bone tissue. Results: Thirteen specimens from eight patients were included in the study. Microscopically, 11 specimens exhibited no recognizable new bone tissue. Two specimens exhibited a small amount of woven bone on the surface of the sinus floor. Conclusion: Within the limits of this study of eight patients, little to no new bone formation was observed on the maxillary sinus floor at 6 months following sinus membrane elevation and support with blood-soaked collagen sponges. Int J Oral Maxillofac Implants 2011;26:83–90
Key words: bone formation, bone graft, lateral window, maxillary sinus, membrane elevation, sinus floor augmentation
Sunday, March 20, 2011
There have been a number of scholarly articles that have explored this question. There have been a number of animal studies and a few human studies - some based on the analysis of post operative radiographs and others on histology. The paper whose abstract is reproduced below questions the claims that bone can be reliably regenerated below an elevated sinus membrane without the use of a graft material. The authors observe that they observed no significant new bone formation . Until we have further clarifying research on the topic it may be wiser to stick to the conventional technique !