Variables Influencing Bone Formation After Transcrestal Sinus Floor Elevation: Radiographic and Tomographic...

Area of Science:

• Dental Implantology
• Oral Surgery
• Biomaterials Science

Background:

• Transcrestal sinus floor elevation (TSFE) is a common procedure for augmenting the maxillary sinus.
• Achieving adequate hard tissue gain is essential for successful dental implant placement.
• The initial positioning of implants relative to the sinus floor may influence bone regeneration outcomes.

Purpose of the Study:

• To investigate the impact of initial implant protrusion into the subantral space on hard tissue augmentation.
• To assess the correlation between initial implant protrusion and hard tissue gain following TSFE with biomaterials.

Main Methods:

• Fifty implants were placed in 44 patients utilizing TSFE with either demineralized bone matrix or deproteinized bone mineral.
• Pre- and post-operative radiographs were taken, with CBCT scans acquired at a mean 6.6-year follow-up.
• Statistical analysis evaluated correlations between initial protrusion, hard tissue gain, and final protrusion.

Main Results:

• Initial implant protrusion averaged 3.5 mm, with an initial bone crest height of 4.6 mm.
• Mean hard tissue gain was 2.5 mm, leaving a residual protrusion of 1.1 mm.
• Significant positive correlations were observed between initial protrusion and hard tissue gain (r=0.55, P=.0001), and between initial and final protrusions.

Conclusions:

• Increased initial implant protrusion into the subantral space positively correlates with greater hard tissue gain.
• Higher initial protrusion also leads to a greater final implant protrusion above the regenerated hard tissue.
• These findings suggest that controlled initial implant positioning is a key factor in maximizing bone regeneration during TSFE.