When the 1.2 mm pilot drill reaches 18 mm from the crest, the nasal floor appears to be perforated. The latter is confirmed by PA (Fig.5). As the osteotomy are increasing in diameter, force is applied as palatally (Lindermann bur is also used) as possible without perforating the palatal wall too much. When a 3.5x20 mm implant is placed (30 Ncm), it is palatal to the labial wall. The defect is filled by allograft and Osteogen, covered by a long termed resorption membrane (Cytoplast).
Xin Wei, DDS, PhD, MS 1st edition 09/05/2015, last revision 01/19/2018