Bone augmentation effect of implant apex flush with maxillary sinus notch in transcrestal sinus floor elevation: A retrospective study.

OBJECTIVES

To retrospectively evaluate whether implant apex flush with maxillary sinus notch is associated with greater bone augmentation of the concave sinus floor after graft-less transcrestal sinus floor elevation (TSFE) and simultaneous implant placement.

MATERIALS AND

METHODS

All patients treated with TSFE between January 2017 and June 2020 were screened via radiographs. Patients with concave sinus floor at the planned implant site were selected and divided according to a cohort design as follows: implant apex flush with the maxillary sinus notch (test group) or not (control group). Panoramic images were taken before surgery, immediately, and 4 months after surgery. Two-dimensional augmentation parameters, including endo-sinus bone gain (ESBG), and the ratio of ESBG to implant protrusion length (%ESBG) were measured to evaluate the bone augmentation effect.

RESULTS

Sixty-nine patients with a total of 69 implants (39: control group, 29: test group, 1: failure) were included in this retrospective research. At the 4-month follow-up, the ESBG and %ESBG of the test group [ESBG: 1.57 (0.58-2.37), %ESBG: 49.68% (15.38%-75.91%)] were significantly higher than those of the control group [ESBG: 0.48 (0.13-1.47), %ESBG: 11.73% (3.05%-27.96%), p < 0.05].

CONCLUSIONS

The present study preliminarily suggests that implant apex flush with the maxillary sinus notch may be associated with better bone augmentation of concave sinus floor in graft-less TSFE.

CLINICAL RELEVANCE: This study is the first to propose the definition of the maxillary sinus notch and preliminarily explore its role in graft-less TSFE, providing novel insights into how implant protrusion length (IPL) affects bone augmentation.