Impact of the Articular Angle on Skeletal Class II Division 1 Malocclusion in Libyan Patients: A Retrospective Cephalometric Analysis

Abstract

The articular angle (S-Ar-Go) is one of the important cephalometric parameters influencing mandibular growth direction, rotation, and overall skeletal morphology. This study aims to assess the relationship between the articular angle and Class II Division 1 malocclusion in Libyan patients, evaluating its role in mandibular retrusion and skeletal disharmony. A total of 116 lateral cephalometric radiographs of Libyan white population patients diagnosed with Class II Division 1 malocclusion (SNA≥ 4) and proclined upper incisors, i.e., overjet > 3 mm) were analyzed using Dr. Ceph software. Measurements included the articular angle (S-Ar-Go), ANB angle, SNB angle, and mandibular plane angle (SN-MP). Statistical analysis was performed using SPSS 12.0 software, employing Pearson correlation analysis and independent t-tests to determine the significance of articular angle variations. A significantly larger articular angle was observed in Class II Division 1 Libyan patients compared to normal Libyan cephalometric values (p < 0.01). The articular angle exhibited a strong positive correlation with ANB (r = 0.312, p = 0.001) and a negative correlation with SNB (r = -0.285, p = 0.002). Additionally, increased articular angles were associated with clockwise mandibular rotation and a steeper mandibular plane. This study confirms that an increased articular angle contributes to skeletal Class II malocclusion by influencing mandibular growth and posterior positioning of the mandible. The findings emphasize the necessity of considering the articular angle in cephalometric diagnosis and treatment planning, particularly in cases requiring orthopedic interventions in growing patients or camouflaging or orthognathic surgery of non-growing patients.