Sinus septa, sloping sinus floor
Sinus septa or a sloping sinus floor are frequent and are not a contraindication for transcrestal sinus lift.
The septum usually runs from palatal to buccal.
Preoperative imaging is not required.
During opening the septum is ablated with the diamond drill.
Deeper in the channel a septum or a sloping sinus floor are gradually absorbed with the osteotome. This is done while alternating with the elevation of the surrounding, exposed Schneider's membrane.