Objectives: This study aimed to evaluate soft tissue adaptation in Class II Division 1 malocclusion patients treated with four premolar extractions and fixed appliances, focusing on the correlation between anterior teeth retraction and soft tissue changes. Materials and Methods: Thirty-one patients (19 with micro-implant anchorage, 12 with conventional anchorage) were treated at Hanoi Central Odonto-Stomatology Hospital. Lateral cephalograms, taken pre- and post-treatment, assessed changes in soft tissue landmarks relative to Rickett’s E-line and the Sn-Pog’ line. Statistical analyses included paired t-tests and Mann-Whitney U tests. Results: Pre-treatment measurements showed no significant differences in Pn-Sn-Ls and Ls-SnPog’, indicating comparable initial soft tissue profiles. However, lip protrusion relative to Rickett’s E-line was significantly higher in the MI group, with upper lip (Ls-E) measurements of 3.4 ± 2.0 mm compared to 2.1 ± 2.5 mm in the conventional group (p = 0.008) and lower lip (Li-E) measurements of 6.3 ± 2.5 mm versus 4.2 ± 2.4 mm (p <
0.001). Post-treatment adaptations revealed that the MI group experienced a greater reduction in lower lip protrusion relative to the E-line (-2.9 ± 1.7 mm) compared to the conventional group (-1.2 ± 2.6 mm, p = 0.034). Other variables, including Ls-SnPog’ and Li-SnPog’, showed no significant differences between the groups. Conclusions: Orthodontic treatment with premolar extraction significantly improved facial aesthetics by reducing lip protrusion. Micro-implant anchorage demonstrated superior control over soft tissue adaptation compared to conventional anchorage, underscoring its efficacy in enhancing treatment outcomes.