Background <p>Skeletal Class II malocclusion with mandibular retrognathia is a common, condition that can compromise oral function and facial aesthetics. The Herbst appliance is an effective fixed functional appliance; however, it may result in mesial movement of mandibular molars and proclination of mandibular incisors. Miniscrews may help mitigate these side effects. This study aimed to compare the dental and skeletal effects of conventional Herbst appliances versus Herbst appliances combined with miniscrews in adolescent patients with skeletal Class II malocclusion and mandibular retrognathia.</p> Methods <p>This retrospective study included 37 adolescent patients with skeletal Class II malocclusion. The control group (<i>n</i> = 20, 12.58 ± 1.09 years, 10 males, 10 females) was treated with conventional Herbst appliances, whereas the experimental group (<i>n</i> = 17, 12.52 ± 0.73 years, 8 males, 9 females) received Herbst appliances combined with miniscrews implanted in the mandibular external oblique ridges. CBCT data were obtained before (T1) and after (T2) treatment, with cephalometric variables measured using Dolphin Imaging software.</p> Results <p>After treatment, both groups showed increased lower incisor proclination, increased mandibular growth and reduced overjet. The experimental group had significantly less increase in IMPA, greater increases in SNB, Co-Go, Co-Gn, and Pog-SP, and a greater decrease in ANB compared to the control group.</p> Conclusions <p>Both control and experimental groups stimulate mandibular growth, but miniscrews provided better anchorage control, resulting in less increase in IMPA, and achieve correction through greater skeletal changes. These results offer preliminary insights for the clinical management of skeletal Class II malocclusion, though further validation through well-designed randomized controlled trials is warranted.</p>