Fig.6: If the bone core comes out with the trephine bur (a), the top corner will be trimmed (b: pink curved lines) so that it will not tear the sinus membrane when it returns as will be mentioned below.  The bone core is to be sectioned as shown in Fig.6c.  The top portion will be placed above the implant, while the lower portion will be ground into small pieces (yellow circles) with a bone mill and placed lateral (circumferentially) to the implant. All of these bone grafts lose direct blood supply.  They obtain blood supply by perfusion.  In contrast, the bone core in Fig.5 gets blood supply directly from the sinus membrane.  Surgery modification will also make it possible for the top portion of bone core to obtain its original blood supply.

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Xin Wei, DDS, PhD, MS 1st edition 09/29/2013, last revision 09/29/2013