Sinus Lift Acute Angles, IMP6577SC Description: Kramer-Nevins Sinus Lift Instrument for Acute Angles. Spoon blades width (4mm/7.4mm). The acute design will facilitat access to the mesial, distal, superior or inferior aspect. Designed to further separate the sinus lining from the bone, without fraying or tearing. IMP6577SC or 6577