Purpose: Many techniques have been proposed to overcome the limitations displayed by maxillary atrophy. The aim of this systematic review was to assess the predictability, dimensional changes, and associated factors to successfully perform the alveolar ridge split (ARS) technique of augmentation. Materials and Methods: An electronic and manual literature searches was conducted by two independent reviewers in several databases, including Medline, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, for articles written in English up to February 2014. A manual search was also performed to ensure a thorough screening process. Based on the PICO (problem, intervention, comparison, outcome) model, the chief question of this study was: Can patients with horizontal ridge deficiency be successfully treated with the ARS technique and implant therapy? Results: Overall, 17 articles met the inclusion criteria, and a subsequent meta-analysis was performed. A Cohen kappa interagreement rate of 0.82 was reached. The implant survival rate of the included studies was 97.0% (range, 94.4% to 100%) with the full-thickness flap (FTF) approach and 95.7% (range, 86.6% to 100%) with the partial-thickness flap (PTF) approach. The weighted mean (WM) of horizontal bone width gain was calculated for included studies using FTF for the ARS technique. Four studies that had data were included in the meta-analysis. The WM ± standard deviation of bone width gain was 3.19 ± 1.19 mm (range, 2.00 to 4.03 mm). For studies using PTF for ARS, only one study provided mean and standard deviation of horizontal bone width gain (4.13 ± 3.13 mm); hence, meta-analysis could not be performed. Buccal wall fracture represented the most frequent postoperative complication, followed by postoperative ridge resorption. Conclusion: In selected scenarios, the ARS technique might represent a predictable approach as demonstrated by a high implant survival rate, adequate horizontal bone gain, and minimal intra- and postoperative complications. Further research is needed to determine the influence of the grafting materials inserted and flap tissue biotype, as well as the anatomical characteristics on final bone augmentation outcomes. Schlagwörter: alveolar ridge augmentation, bone regeneration, dental implants, osteotomy, systematic review, treatment outcome