Quick Answer
When is a sinus lift needed?
It is needed when the bone height remaining beneath the maxillary sinus in the upper molar area is shorter than the implant. Yeonhap Dental Clinic considers it when residual bone is under 7 mm on 3D CBCT, and even when only 1–2 mm of bone remains, it tries hydraulic elevation first if the sinus membrane is healthy. The most common complication is sinus membrane perforation, reported at 7–58%. It is not needed for lower molars or front teeth.
How is it decided whether a sinus lift is needed?
On the CT scan, we look at three things: the height of the residual bone, the thickness and inflammation of the sinus membrane, and whether the implant can achieve initial stability. Please tell us if you have a history of sinusitis or nasal symptoms. If the sinus is inflamed, treating the inflammation comes before the lift.
How do sinus lift methods, risks, and duration differ?
The crestal approach raises the sinus floor through the implant site, so the incision is small. The lateral approach opens a window in the bone on the cheek side and lifts the membrane under direct view, and is used when a lot of bone is missing. With both methods, membrane perforation is the most common complication. When a sinus lift is added, the grafted bone needs time to settle, so treatment takes longer. The durations given are the total time from the first surgery to the final prosthesis: about 4–5 months when conditions are good, about 6–7 months when adaptation to a temporary tooth is needed, and about 7–8 months when the lift is done first and the implant is placed later.
How does Yeonhap Dental Clinic perform a sinus lift?
With the crestal approach, instead of the osteotome method, Yeonhap Dental Clinic uses hydraulic elevation, which spreads force across the whole membrane and reduces the chance of perforation, and checks for perforation using the Valsalva maneuver, air bubbles, saline leakage, and membrane elasticity together. If the signs of perforation are ambiguous or confirmed, we treat it as a perforation and switch to the lateral approach on the same day to repair the membrane and place bone graft, and if initial stability is achieved, we complete the implant placement as well. If the membrane is thin or a lesion is visible inside the sinus, we consider the lateral approach from the start. If sinusitis is present, we proceed after rechecking with CBCT 3 months after extraction. The criteria for choosing an approach are in the sinus lift column.
References
Pjetursson BE, et al. A systematic review of the success of sinus floor elevation and survival of implants inserted in combination with sinus floor elevation. J Clin Periodontol. 2008. Tan WC, et al. Same title, Part II: transalveolar technique. J Clin Periodontol. 2008. Shi S, et al. Clinical efficacy of transcrestal sinus floor augmentation, in comparison with lateral approach, in sites with residual bone height ≤6 mm: a systematic review and meta-analysis. Clin Oral Implants Res. 2023. Kadkhodazadeh M, et al. Clinical outcomes of implants placed with transcrestal maxillary sinus elevation: a systematic review and meta-analysis. Br J Oral Maxillofac Surg. 2024. Sirinirund B, et al. Minimally invasive sinus augmentation: a systematic review. Clin Implant Dent Relat Res. 2025.
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Before Your Visit
This article is general guidance for implant consultations. Whether treatment is possible and the actual cost may change after an oral examination and 3D CBCT diagnosis. If you have discomfort such as pain, swelling, or looseness, please come in for a consultation so we can check.