Bone harvest of mandibular symphysis has been used in maxillofacial reconstruction procedures. The aim of this research was to establish the presence of bone repair into osseous defect caused by removal of bone. Thirty patient s, 2 female and 8 male, ranging between 21 and 65 years of age underwent surgery for chin bone harvest and alveolar reconstruction. The surgery was performed by two maxillofacial surgeons and the patients were evaluated with lateral radiography in the pre-operatory stage, in early post-operatory and in late post-operatory stages. Horizontal and vertical measures of bone defect were realized; the dates were analyzed by Student t test with a value of p<0.05. After bone harvest, a vertical defect of 12.80 +/- 1.99 was observed and a horizontal defect of 8.33 +/- 1.77 was observed. After one year the defect decreased to 32.8% in vertical evaluation, and 50.3% in the horizontal evaluation with a statistical significance (p<0.05) in relation to the early post-operatory stage. Therefore, we conclude that in bone repair of mandibular symphysis defect is close to 30 - 50% in a one-year follow-up.