This study aimed to evaluate the clinical complications that might be presented with osteotome and densah burs, as well as to assess the new bone generated at 6 months post-operatively using CBCT. The study hypothesis was that densah bur would show comparable results to osteotome-mediated sinus lifting

Maxillary posterior edentulous area rehabilitation with implants is usually not an easy procedure and is considered a challenge to many prosthodontists. This is due to pneumatization of the maxillary sinus, poor bone density and volume, and difficult accessibility of this area. After tooth loss, the maxillary sinus tends to enlarge into the remaining residual ridge because of poor bone density and lack of functional stimulation by teeth.1 Rehabilitation with dental implants in the maxillary posterior area depends on the quantity and quality of bone available for implant placement. In order to place the implant in the best prosthetic position, regenerative surgical techniques are usually essential to correct the initial anatomical situation.2 Summer in 1994 introduced a less invasive technique than the lateral approach for sinus floor elevation, called the closed sinus lifting. Summer classified it in to osteotome sinus floor elevation and bone added osteotome sinus floor elevation. Osteotome depends on condensing the bone in implant bed site and pushing it laterally and upward, which raises the sinus floor. Although being successful and non-invasive, Summer's technique showed several surgical problems as heat generation-induced necrosis if not well irrigated, and delayed implant secondary stability, as well as some patient-related drawbacks as headache and vertigo.3 Fortunately, in 2014 Salah Huwais introduced new burs called densah burs that help preservation of bone health by condensing bone rather than removing it. Accordingly, this process was labeled osseodensification. In the past few years since the introduction of densah burs, limited number of studies evaluated its efficiency as well as patient perception to the procedure. 4 It is well established that cone beam computed tomography (CBCT) gives more profound and accurate assessment of pre- and post-operative implant sites. However, a meta-analysis was published in 2018 showed that most previous studies on lifting procedures used conventional 2D techniques, and very few applied CBCT as the diagnostic modality. This heterogeneity highly affected the quality of evidence retrieved. 5 This study aimed to validate the clinical complications that might be presented with osteotome and densah burs, as well as to assess the new bone generated at 6 months post-operatively using CBCT. The study hypothesis was that densah bur would show comparable results to osteotome-mediated sinus lifting.

Inclusion Criteria:

• the residual bone height at the site of implant placement was 8 mm or less. All patients were in a good health, non-smokers with no systemic, immunologic or debilitating diseases that could affect normal bone healing. Their edentulous ridges were covered with optimal thickness of mucoperiosteum with no signs of inflammation, ulceration or scar tissue and sufficient inter arch space was adequate for future prosthesis

Exclusion Criteria:

• smokers bad oral hygiene systemic disease

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