In conclusion, the repositioning of the bone window after sinus floor elevation in sheep, compared with the use of a resorbable membrane, improved the closure of the antrostomy and led to a greater amount of the newly formed bone in the close-to-window zone of the grafted area. The bone window appeared partially bonded to the newly formed bone. Bridges of new bone from the edges of the antrostomy reached the repositioned bone window. The newly formed bone was found interpenetrating the graft granules. The cyanoacrylate used to close the antrostomy showed no inflammatory response.

The limitations of the present study were the lower phylogenetic level and thicker sinus mucosa of sheep compared with humans. The small number of animals used, complicated by the reduction of the sample from eight to six, was another limitation of the study.