The aim of this study was to investigate the effectiveness of the split-box technique, a novel technique that combines the ridge splitting and split bone block techniques.

In this retrospective study, alveolar ridge defects were grafted using the split-box technique and its modifications, reverse split box and sliding split box. To determine horizontal changes in the alveolar bone, thickness was measured at two levels: crest width (CW) and screw level width (SLW). Alveolar ridge height (ARH) was also measured to detect a possible loss of vertical dimension. Measurements were performed using cone-beam computed tomography taken before the operation (T0) and at five months after the operation (T1).

Of a total of 41 patients included, 21 were females and 20 were males with a mean age of 44.5 ± 13.3 years. A total of 64 regions were augmented. Among the augmented regions, split-box technique was used in 31 regions, reverse split-box technique was used in 14 regions, and sliding split-box technique was used in 19 regions. The increase at the SLW, CW and the decrease in ARH from T0 to T1 was statistically significant (p < 0.005). A significant difference was found between split box and its modifications in terms of bone gain at the screw level, and the sliding box technique was associated with more bone gain than the other two methods (p < 0.05).

Split-box technique provides a comparable net gain in the alveolar crest width with lower complication risk than ridge split technique and lower postoperative morbidity than split bone block technique.