The findings were as follows: (1) Hard-tissue changes were only observed in the maxillary region. Soft-tissue changes included backward displacement of the subnasale and the upper and lower lips. (2) The highest correlation coefficient was obtained between hard- and soft-tissue changes in the upper lip region. (3) The horizontal soft-tissue change in the upper lip region was predicted using a multiple regression equation. These results suggest that anterior maxillary osteotomy influences hard- and soft-tissue changes in the upper lip region and that the response in the horizontal dimension in association with surgery can be predicted.