Why the upper back jaw loses bone

Each upper molar sits beneath an air-filled cavity, the maxillary sinus. When the tooth is lost, two things happen at once: the ridge shrinks from the top, and the sinus expands downwards into the space the roots occupied, a process called pneumatisation (Resnik & Misch, 2018). The remaining bone is also the softest in the mouth. The result is a region where implants need help from grafting more often than anywhere else and where the complications textbook notes that the posterior maxilla “is responsible for more complications in oral implantology than any other region”.

What a sinus lift actually does

The sinus is lined by a thin membrane. In a sinus lift the surgeon lifts this membrane away from the bony floor and places graft material in the space created, inside the bony cavity but outside the lining, so the sinus itself stays sealed (Hupp et al., 2014). Graft options include the patient’s own bone, processed donor bone, bovine-derived mineral, growth factors or combinations; the autogenous component matters most when very little native bone is left (Hupp et al., 2014; Resnik & Misch, 2018). Our bone graft page describes the materials in more detail.

Lateral window or crestal: how the bone height decides

Misch classified the sinus region by the bone remaining under it, and the classification is still the practical decision tool (Resnik & Misch, 2018):

The crestal technique (also called osteotome or transalveolar) works through the small hole prepared for the implant, pushing the floor upwards by a few millimetres. It is less invasive, but a membrane tear cannot usually be seen, and an oblique sinus floor, bony partitions, sinus pathology or a blocked drainage opening may rule it out (Resnik & Misch, 2018). The lateral window opens a small door in the side wall of the sinus under direct vision, allows larger gains and makes a tear visible and repairable (Hupp et al., 2014).

Simultaneous or staged implants?

Placing implants at the time of the lift saves a surgery and months of healing, but only when the remaining bone can hold them still. The criteria cited for a simultaneous approach are more than 5 mm of height and 6 mm of width, reasonably firm bone, no sinus pathology or recurrent sinusitis, no tear or only a small sealed one, and no grinding against a removable denture; with very soft bone, recently treated pathology, smoking or medical compromise, or a medium to large tear, the implants are delayed (Resnik & Misch, 2018). The surgical textbook gives a similar threshold: 4–5 mm of bone allows simultaneous implants, while less means the graft heals 3–6 months first (Hupp et al., 2014). The final decision is sometimes made during surgery, depending on what the membrane does.

Before surgery: checking the sinus itself

Roughly 46% of patients who are candidates for a sinus graft show some sinus finding on CBCT without any symptoms (Resnik & Misch, 2018). We check that the drainage opening of the sinus is clear and look for thickened lining, cysts or fluid; where needed we refer to an ear, nose and throat specialist before grafting. Active sinusitis, a blocked opening and untreated pathology are reasons to postpone. Smokers are counselled that implants in grafted sinuses fail at almost twice the rate (Resnik & Misch, 2018).

Healing and the visit plan for international patients

1. WhatsApp pre-assessment: a panoramic X-ray gives a first impression of bone height; the CBCT decides.
2. Visit 1 (generally 3–5 days): examination, CBCT, sinus lift with or without simultaneous implants, a check the next day, and written after-care instructions. A relieved denture can usually be worn over the site (Hupp et al., 2014).
3. Healing: with simultaneous implants, generally 6 months or more before the prosthesis; with a staged graft, 3–6 months before implants and 4–8 months in total before loading (Hupp et al., 2014; Resnik & Misch, 2018).
4. Implant visit (staged cases, generally 3–5 days), then the implant healing period.
5. Prosthesis visit (generally 5–7 days).

Risks and how they are managed

Membrane perforation is the most common complication, reported in a wide range of 10–60% of procedures depending on technique and anatomy; piezoelectric instruments are the safest, rotary burs the most perforation-prone (Resnik & Misch, 2018). A tear is covered with the redundant membrane and a resorbable collagen patch so that grafting can continue (Hupp et al., 2014). Other complications include infection, partial loss of graft, bleeding, an oroantral communication and, after the crestal technique, a brief benign positional vertigo in around 3% of cases; overall sinus-graft complication rates of 0–32% are cited (Resnik & Misch, 2018). In the long run, implants in grafted sinuses are part of the general implant survival picture, with fixed implant prostheses showing about 95% survival at five years (Pjetursson et al., 2012), provided maintenance is kept up (see implant aftercare).

What determines the cost of a sinus lift?

• Technique: crestal versus lateral window, one side or both.
• Graft material and membrane type and volume.
• Simultaneous implants or a staged approach with a separate surgery.
• Imaging and ENT assessment where needed.

A written fee follows the examination and CBCT; see the prices and campaigns page for our fee structure and instalment options.

Searching for the “best sinus lift in Istanbul”: what to check

• Is the technique chosen from the measured bone height on a CBCT, with the reasoning explained?
• Has the sinus itself been assessed for pathology and a clear drainage opening?
• Does the clinic explain whether implants will be simultaneous or staged, and what could change that during surgery?
• Are after-care rules given in writing, and is there a contact for problems after you fly home?
• Is smoking addressed openly as a risk factor?

Frequently asked questions

Related guides

Medical content review: Dr. Dt. Mehmet Fuat BozabaHead physician, works in periodontology and oral surgery · Last updated: October 2026 · About the head physician

Contact: Yayla Dental Akademi, Ferit Selimpaşa Cad. No:44A, Bahçelievler, Istanbul (Basın Sitesi, opposite Migros; about 600 m from İlkyuva metro station). Monday–Saturday 10:00–21:00, Sunday closed. WhatsApp and phone: +90 544 289 66 33 · Online booking: DoktorTakvimi.

Sources

This page is for information only; diagnosis and treatment plans are determined by a dentist after an examination. Complication and survival figures are ranges from the cited sources and do not describe an individual outcome.