Graftless Sinus Floor Elevation Using the Lateral or Transcrestal Approach. A Randomized Clinical Trial With One Year Follow‐Up

INTRODUCTION: This randomized clinical trial aimed to evaluate implant stability following graftless lateral window and crestal implant approaches for maxillary sinus floor elevation (MSFE) 1 year after implant placement. METHODS: Twenty-six single missing posterior maxillary teeth indicated for delayed implant placement, with a residual ridge height of 4-6 mm, were randomly assigned to perform either graftless lateral window (control) or crestal implant (test) approaches for MSFE. Implant stability was assessed using resonance frequency analysis; intra-sinus vertical bone gain and marginal bone loss were measured via CBCT 1 year after implant placement. Clinical parameters and patient-reported outcomes were also measured. RESULTS: The reported implant stability quotient (ISQ) values were not significantly different between the lateral window and the crestal implant approaches (80.92 ± 4.57 and 80.19 ± 7.28, respectively) 12 months after implant placement. However, the lateral window approach revealed a significant increase (p < 0.001) in the mean ± SD intra-sinus vertical bone gain at 6 and 12 months (3.64 ± 0.84 mm and 3.82 ± 0.84 mm, respectively) compared to the crestal implant approach (1.66 ± 1.27 mm and 2.42 ± 1.39 mm, respectively). However, no intergroup significant difference was noticed concerning average marginal bone loss (p = 0.31) after 12 months. Postoperative complications and patient discomfort were more evident in the lateral window approach group. CONCLUSION: In patients with a residual ridge height of 4-6 mm receiving implant therapy in conjunction with maxillary sinus elevation without graft material, there was no statistically significant difference in implant stability at 12 months between a lateral window and transcrestal sinus approach. Greater vertical bone gain was achieved following the lateral window approach.