Skeletal and dental features of class II malocclusion among Palestinian population: a retrospective cephalometric study

Aim. This study aims to assess the dentofacial characteristics for a sample of palestinian population with skeletal Class II malocclusion. Methods. A total of 170 lateral cephalograms for non-growing patients (age ranged between 19 and 32 years) with skeletal Class II malocclusion were retrieved. The lateral cephalograms were analyzed using virtual cephalometric analysis software - WeDoCeph® (Audax®, Ljubljana, Slovenia) to assess sagittal and vertical Skeletal parameters including SNA, SNB, ANB, SN/Mandibular Plane angle SN/Go-Gn, FMA and the Y axis angle were measured. Moreover, the upper and lower dental angular parameters (Maxillary incisor long axis with Sella - Nasion line (U1-SN), Maxillary incisor long axis with Nasion - point A angular (U1-A Point), Mandibular incisor long axis with mandibular plane (L1-MP), Mandibular incisor with nasion-point B (L1- NB) angular were also measured. The mean and standard deviation for each measurement were calculated using the Statistical Package for Social Sciences (Minitab) for Windows. Gender differences were analyzed using the independent t-test. Results. One-hundred and seventy lateral cephalometric radiographs were retrieved and analyzed. The Class II skeletal value (ANB value of 6.7 degrees) was mainly due to retrognathic mandible (SNB 75.5 degrees) rather than prognathic maxilla (SNA 82.2 degrees). In the vertical dimension, the Y axis angle, SN/Go-Gn angle, and FMA were generally increased. Regarding the dental parameters, the upper incisors were mostly retroclined, while the lower incisors were mostly proclined. There was a significant gender difference in two parameters (SN/Go-Gn and the L1-MP), where females showed more vertical growth and more lower incisors proclination. Conclusions. Skeletal class II malocclusion in the studied sample was characterized by retrognathic mandible, increased vertical growth, and compensated upper and lower incisors. Compared with male subjects, females significantly had more vertical growth and more lower incisor proclination.