Maxillary sinus augmentation by crestal access: a retrospective study on cavity size and outcome correlation

Area of Science:

• Oral Surgery and Implantology
• Radiology and Imaging
• Biomaterials Science

Background:

• Crestal sinus elevation is a common procedure to augment bone height for dental implants.
• Mineralized human bone allograft is utilized for sinus augmentation.
• Maxillary sinus size can influence the outcomes of sinus elevation procedures.

Purpose of the Study:

• To analyze cone-beam computed tomography (CBCT) and radiographic outcomes of crestal sinus elevation.
• To correlate these outcomes with maxillary sinus size.
• To evaluate the predictability of the crestal technique in sinuses with initial bone height ≤5 mm.

Main Methods:

• Sixty sinus augmentations were performed in 60 patients with initial bone height ≤5 mm.
• Digital radiographs and CBCT were used for evaluation from surgical placement up to 72 months post-loading.
• Marginal bone loss (MBL), intra-sinus bone loss (IBL), sinus size, and implant distances were analyzed using ANOVA and linear regression.

Main Results:

• Marginal bone loss (MBL) increased over time and was correlated with 6-month MBL.
• Intra-sinus bone loss (IBL) correlated significantly with sinus wall distance and time.
• Greater IBL was observed in wide sinuses (≥13.27 mm) compared to narrow sinuses (<13.27 mm).

Conclusions:

• The crestal sinus elevation technique with <5 mm residual ridge height is more appropriate and predictable in narrow maxillary sinuses.
• This predictability is specifically related to achieving better intra-sinus bone coverage.
• The study provides the first quantitative, statistically significant evidence supporting this conclusion.