Safe sinus lift: use of acrylic stone trimmer to avoid sinus lining perforation.

Iatrogenic injury to the maxillary sinus membrane is a common complication during direct sinus lift procedures. The most common cause is perforation of the Schneiderian membrane using a tungsten-carbide round bur no.6. We propose a safe technique in which an acrylic stone trimmer is used to create a window in the maxillary antrum thereby minimizing the risk of injury to the delicate sinus membrane.