This present study will evaluate Schneiderian membrane perforation rates using osseodensification in TSFE with simultaneous graftless implant placement, under sinuscopic control monitored by an ENT specialist.

An endoscopic evaluation will be continuously conducted throughout the surgical procedure. TSFE will be performed using Densah burs without the addition of bone graft material, followed by implant placement. The rationale behind this approach is to monitor the response of the Schneiderian membrane and assess the effects of Densah burs on membrane distention and the occurrence of SMP.

Inclusion Criteria:

• males and females over 21 years of age;
• partial edentulism in the posterior maxilla involving 2 or more adjacent teeth in the premolar-molar area;
• teeth at the intended implant sites must have been extracted or lost at least 9 months before the date of implant surgery;
• sinus floor with a relatively flat contour confirmed on baseline CBCT;
• bucco-palatal sinus width (distance between the buccal and palatal walls at 10-mm apical level comprising the residual alveolar crest ) 8-12 mm confirmed on baseline CBCT to minimize the risk of SMP during surgery (Stacchi et al. 2022);
• sinus membrane thickness ≤ 2 mm;
• subsinus residual bone height (RBH) 4-6 mm at the intended implant sites and bucco-palatal bone width allowing implant placement without bone augmentation procedures.

Exclusion Criteria:

• systemic conditions contraindicating implant surgery;
• pregnancy or lactation;
• ongoing or history of pathologies or medications affecting bone metabolism;
• ongoing or history of head and neck irradiation;
• oral inflammatory and autoimmune diseases;
• presence of osseous lesions or persistent infections in the planned implant sites;
• previous bone augmentation surgery;
• uncontrolled periodontal diseases;
• heavy smoking (> 10 cigarettes/day);
• history of sinus surgery;
• presence of intrasinus bony septa that could affect membrane elevation and distention; and
• ongoing or history of rhinitis or sinusitis.