Comparison of two surgical techniques (osseodensification versus lateral window) for maxillary sinus augmentation

Plain English summary of protocol

Background and study aims
Dental implants are an excellent treatment option for edentulous patients (missing teeth) with high success rates. Historically, the posterior maxilla (the bone that forms the upper jaw) has been associated with a higher rate of implant failure. In addition to the low bone density, a frequent limitation for implant placement in the posterior maxilla is the reduced residual bone height associated with maxillary sinus pneumatization (increase in sinus volume).
In these extreme cases, there are two possible surgical approaches to elevate the sinus mucosa: the classical lateral window approach or the crestal approach. The lateral window technique was initially developed in the 1970s and is still widely used today. It is a very predictable technique but it is associated with higher patient morbidity (illness). This approach requires a wide surgical flap with vertical releasing incisions, contrary to the crestal approach. This more extensive surgical approach can result in increased pain, face swelling and ecchymosis (discoloration of the skin). In addition, during the preparation of the lateral window, there may be disruption of blood vessels. The potential risk of infection is also higher compared to the crestal approach.
Later, in 1994, a new technique for maxillary sinus elevation through the crestal approach using osteotomes (surgical dental instruments) was suggested. This crestal approach is less surgically invasive, though the repeated impact of a hammer for the progression of osteotome is very traumatic with potential unintentional displacement, fracture or side effects such as benign paroxysmal positional vertigo (mild to intense dizziness).
In 2015, a new concept of implant site preparation termed osseodensification was described. This technique recommends the use of burrs specially designed to rotate in a non-cutting mode, counterclockwise at 800 to 1200 rpm, for bone densification through compaction autografting. The burs are dual-action and can also be used in cutting mode (clockwise direction). Through this technique, it is possible to expand the bony crest, creating a layer of compacted bone along the implant bed walls. Since it “pushes” the bone instead of removing it, osseodensification has the capacity to prepare the implant site while elevating the sinus membrane with lower morbidity than the classical technique.
In 2018, a study showed osseodensification allowed sinus elevation in cases with residual bone height as low as 2 mm, without the disadvantages inherent to the lateral window technique and the osteotome technique. The main advantages of osseodensification compared to osteotomes are: it is substantially less traumatic for the patient (since it is not necessary to use a hammer to penetrate the cortical of the maxillary sinus); it allows greater increases in height and it can also be used with high predictability in cases with oblique sinus floor. In addition, osseodensification has the inherent advantage of all the crestal approach techniques – the preservation of the buccal bone wall.
The aim of this study is to compare the osseodensification technique with the classical lateral window technique for maxillary sinus elevation in cases with residual bone height less than 5 mm.

Who can participate?
Patients aged 22 or older with at least one tooth missing in the posterior maxilla and reduced residual bone height

What does the study involve?
Patients will be randomly allocated to surgery with osseodensification or the lateral window technique. With the exception of the surgical technique used, all other treatment will be similar for both groups. Patients will be followed up for 6 months after surgery and until the implants are loaded with the final restoration. Pain perception is measured during the first week after surgery.

What are the possible benefits and risks of participating?
The risks of participating in the study are the risks inherent to the surgical procedure itself, which patients would need in any case.

Where is the study run from?
Egas Moniz University Dental Clinic (Portugal)

When is the study starting and how long is it expected to run for?
October 2020 to August 2022

Who is funding the study?
Investigator initiated and funded

Who is the main contact?
João Gaspar
jgaspar@egasmoniz.edu.pt

Contact information

Dr João Gaspar
Public

Rua Fontes Pereira de Melo, 161 1ºdto
Montijo
2870-476
Portugal

ORCID ID	0000-0002-2758-2667
Phone	+351 (0)911909629
Email	jgaspar@egasmoniz.edu.pt

Study information

Eligibility

Locations

Countries of recruitment

• Portugal

Study participating centre

Sponsor information

Funders

Funder type

Other

Results and Publications

Study outputs

Editorial Notes

05/12/2023: Publication reference and total final enrolment added.
04/04/2023: The intention to publish date was changed from 01/10/2022 to 31/12/2023.
03/05/2022: The target number of participants was changed from 30 to 20
08/10/2020: Trial's existence confirmed by Egas Moniz Ethics Committee.