Influence of the height of the antrostomy in sinus floor elevation assessed by cone beam computed tomography- a randomized clinical trial.

PURPOSE: To evaluate the influence of the height of the antrostomy on dimensional variations of the elevated space after sinus floor elevation. MATERIALS AND METHODS: Twenty-four healthy volunteers planned for sinus floor elevation were included in the study. An antrostomy of either 4 mm (Group A) or 8 mm (Group B) in height was prepared in the lateral wall of the sinus. Cone beam computed tomography (CBCT) scans were taken before surgery (T0) and after 1 week (T1) and 9 months (T2). Dimensional variation analyses were performed. RESULTS: The CBCT scans of 10 patients per group were evaluated. After 1 week (T1), the sinus floor was found elevated in the middle region by 12.0 +/- 2.3 mm in Group A, while in Group B, the height was 11.8 +/- 2.1 mm. After 9 months (T2), the respective heights were 9.9 +/- 2.4 mm and 8.9 +/- 2.7 mm, with a reduction of -2.1 +/- 2.2 mm in Group A and -3.0 +/- 2.6 mm in Group B. The area in a central position was reduced by 25.5% to 34.2%, showing a slightly higher shrinkage in Group B compared with Group A. However, no statistically significant differences were found between the two groups. DISCUSSION: In maxillary sinus floor elevations performed by the lateral approach, the size of the antrostomy did not affect the clinical and radiographic outcomes.