The left side of the image is the lump of bone I created in the sinus.
The sinus is a hollow space above your upper molar teeth. There is usually not enough bone to place implants. The sinus lift bone graft builds the vertical height only. It does not build width. And it only builds height internally… Not externally where you can see in your mouth
If you avoid the sinus lift and place really short implants, they are likely to fail.
Ideally the implants are no less than 4.7mm wide in the sinus. Also the implants should be no less than 10 mm tall.
A very normal size implant that I place place in the sinus on a daily basis is a 5.2 x 13 mm or a 5.2 x 11.5 mm. Sometimes a very wide job and will except a 7.0 mm x 11.5 mm
Of course there are exceptions where biomechanically a shorter smaller Implant may be able to be connected to a larger, longer Implant to make up for it.
In two decades of doing sinus lift bone grafting both lateral window and internal I can tell you that size matters.
That being said bigger is not always better!!
I also find that many less trained dentists try to avoid this procedure and push the limits of the closed/internal version of the sinus lift bone graft. This technique of trying to go beyond the limits of what internal sinus lifting can do often ends up with failed implants and torn sinus membranes!!!
Both the lateral window and internal/crestal approach are both very good. I do both of them. The problem is when somebody only knows how to do one version that particular technique is pushed too far and Implant can end up dislodging and get stuck in the sinus…I remove one last week for another dentist
Ramsey A. Amin, D.D.S.
Diplomate of the American Board of Oral Implantology /Implant Dentistry
Fellow-American Academy of Implant Dentistry