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Introduction This study aimed to determine the vertical and horizontal soft-tissue vs hard-tissue changes after isolated functional genioplasty and to revisit hard-tissue remodeling at the symphysis. Methods Seventy-five patients who underwent genioplasty as an isolated procedure at the end of their orthodontic treatment were divided into three groups based on their age at surgery: < 15 years (group 1), 15–18 years (group 2), and 19+ years (group 3). Patients were evaluated at three time points: immediately before surgery (T1), immediately after surgery (T2,) and two years after surgery (T3). In addition, 25 patients who did not accept genioplasty, were age-matched with group 1, and had a follow-up radiograph two years after the end of their orthodontic treatment, were used as a control group. Results From T2 to T3, group 1 showed less forward horizontal hard-tissue and soft-tissue changes at the pogonion (Pg) than the control group; however, no difference was noted for vertical changes at the menton (Me) and soft tissue menton (Me'). From T1 to T3, the horizontal hard-tissue and soft-tissue changes at the Pg were 6.39 mm and 6.72 mm, respectively, for surgical groups. Vertical hard-tissue change at the Me showed a reduction of 1.63 mm (95% confidence interval [CI], -3.37 to 0.11) and 3.89 mm (95% CI, -5.83 to -1.95) in nongrowing female and male patients, respectively. The vertical soft-tissue change reduction was similar for nongrowing male and female patients (1.7 mm [95% CI, -2.96 to -0.45]). Soft-tissue thickness change at the Pg (0.33 mm) was not significant. In contrast, a small but significant increase in soft-tissue thickness was noted at the Me (0.54 mm). Linear regressions were calculated for all groups and allowed us to predict long-term soft-tissue changes (T3-T1) using the amount of surgical displacement (T2-T1). Conclusions The horizontal hard-tissue change was stable for nongrowing patients, and the horizontal soft-tissue change was 92% of hard tissue. Vertical soft-tissue change is less predictable. Variation of soft-tissue thickness after genioplasty can be explained by skeletal changes and the achievement of an unforced labial occlusion. These results support the functional and esthetic benefits of this surgery. Comparison with the control group showed that genioplasty does not change the growth pattern, and bone remodeling is likely to explain the difference noted at the Pg.