OBJECTIVE The aim of this study was to evaluate the literature regarding clinical efficacy and predictability of block allograft for restoration of vertical and/or horizontal bone defects. METHODS A literature search was conducted in PubMed/MEDLINE and Cochrane databases about studies reporting the use of block allografts. The review included studies published in English from 1960 to 2011 and excluded single-case reports and articles that did not use block allograft stabilized by fixation screws. RESULTS The search revealed 567 articles, but only 14 were included, which were conducted in humans with a total of 194 patients treated with block allografts, totalizing 253 blocks. CONCLUSIONS Although a high success rate has been reported for the bone allograft survival, this systematic review demonstrated low level of scientific evidence articles with short follow-up time and diversified methodology with difficult possibilities to compare their results.