Pouch versus non-pouch technique for repairing the maxillary sinus membrane large perforation in rhesus monkey.

Background: Sinus membrane perforations occasionally occur during sinus lifting procedures. This study utilized rhesus monkey models to compare the effectiveness of two techniques (pouch and non-pouch methods) in repairing large perforations, with a focus on their impact on bone regeneration.

Methods: In five male rhesus monkeys, both sides of the sinus membrane were elevated and perforated. Each sinus was assigned to one of two groups: (a) the collagen membrane covered the perforated sinus membrane and all sinus walls formed a pouch (pouch Group); (b) the collagen membrane covered the perforated sinus membrane (non-pouch Group). Both sinuses were grafted with the same amount of deproteinized bovine bone mineral (DBBM). Follow-up computed tomography (CT) scans were performed at 1 and 9 months, and all monkeys were euthanized at 9 months for micro-CT and histomorphometric analysis.

Results: The quantitative analysis of CT images showed no significant differences in the augmented height, density, and volume of grafted bone between the two groups at 1-month and 9-month follow-up. Similarly, the morphometric and histomorphometric analyses showed no significant differences. However, a notable discrepancy in bone modeling was observed between the two time points (P = 0.0227) along with a significant difference in the sphericity of new bone (P = 0.0446).

Conclusions: The pouch technique may lead to more stable outcomes compared to the non-pouch technique, which has been documented as a promising approach to mitigate graft volume loss and enhance graft stability and aggregation. Besides, no significant difference was seen between pouch and non-pouch techniques in promoting bone regeneration for repairing perforations of the maxillary sinus membrane.

Plain Language Summary: This study explored two surgical techniques for repairing large perforations in the sinus membrane during dental procedures, focusing on the bone growth outcome. We compared the "Loma Linda Pouch" technique, which uses absorbable membrane to create a pouch that surrounds the inner surface of the sinus, to a traditional method. We measured various outcomes, including bone height, density, and overall volume, at 1 month and 9 months after surgery. Both techniques showed substantial and ideal bone growth, but the pouch method may help stabilize the bone graft and minimize graft volume loss in the long run. Importantly, both methods led to effective healing without major complications, and our findings showed that the absorbable membrane does not hinder new bone formation. These insights can assist dental professionals in selecting the most effective approach for sinus surgeries, ultimately improving the success of dental implants and enhancing patient outcomes.