There are 2 types of sinus lift: open and closed. Closed sinus-lifting is performed when the bone tissue in the projection of the maxillary sinuses is at least 10 mm. If this distance is less than 10 mm, open sinus-lifting is applied.

The "external"/"open" sinus lift is done when the sinus is very large and there is very little bone in the sinus. This procedure involves creating a 'window' in the bone through which the doctor pushes the sinus membrane. In open sinus lift surgery the cavity is filled through this hole in the front wall of the sinus above the roots of the teeth. The membrane is then applied. Bone regeneration takes place within 4-6 months.

"Sinus-lifting" is recommended for atrophy of the upper jaw. The cancellous bone of the upper jaw is very different from others - it has more space and small volume of bone tissue. When the tooth is lost, pneumatization of the sinuses occurs and the quality of the bone tissue worsens.

In order to correctly assess the amount of bone present, basic investigations such as panoramic X-rays provide an overview and CT (computed tomography) for a more detailed picture of bone structure and density.