A comparative evaluation of the effects of reverse headgear and the CS5 system on the maxilla and mandible in growing patients with class III malocclusion

Face mask therapy has long been used in the early treatment of Class III malocclusions, whereas the newly developed CS5 System has been introduced as an alternative that reduces patient compliance requirements. This study aimed to compare the skeletal, dental, and soft tissue effects of face mask and CS5 appliances in growing patients. The study sample comprised 40 individuals: 20 patients treated with the CS5 System and 20 patients treated with face mask therapy, matched for age, sex, and growth stage. No significant differences were found between the groups in terms of age or sex distribution. Lateral cephalometric radiographs taken before treatment (T1) and after treatment (T2) were evaluated. Measurements were performed using Dolphin Software Ceph Tracing, and statistical analyses were carried out with the R program, with a significance level set at p<0.05. According to the findings, the face mask group showed significant increases in SNA° and Co-A values as well as effective mandibular length (Co-Gn) (+3.5 mm). In contrast, the CS5 group exhibited no change in Co-Gn (−0.02 mm), with a significant intergroup difference. Maxillomandibular relationship parameters (ANB°, Wits, Convexity) improved significantly in both groups. The CS5 group demonstrated marked retrusion and uprighting of mandibular incisors, whereas changes were limited in the face mask group. Vertically, posterior mandibular rotation and increases in Y-axis and facial heights were more evident in the face mask group. Regarding soft tissues, upper lip support increased in the face mask group, while the CS5 group showed significant retrusion of the lower lip relative to the E-line. In conclusion, face mask therapy was characterized by skeletal maxillary effects, whereas the CS5 System primarily exerted dentoalveolar and soft tissue adaptations. The CS5 appliance may serve as an alternative to face mask therapy in mild to moderate Class III cases with increased lower facial height, poor cooperation, and high esthetic expectations. Keywords: Reverse Headgear, CS5 System, Class III Malocclusion, Cephalometric Analysis