Distribution of the Condylion-Gonion-Menton (CoGoMe^) Angle in a Population of Patients from Southern Italy

The condylion-gonion-menton angle (CoGoMe(boolean AND)) is commonly used as a pre-treatment indicator of responsiveness in Class II patients treated with functional appliances. The distribution of this angle in the Caucasian population is still unknown. This study aimed to determine the distribution of the CoGoMe(boolean AND) and its relationship with age, sagittal jaw relationship (ANPg(boolean AND)), and mandibular inclination (SN(boolean AND)GoGn) in patients from Southern Italy. The sample included 290 subjects (median14 years of age; Interquartile range, IQR, 12-17) with lateral cephalograms taken before the orthodontic treatment. The distribution of the CoGoMe(boolean AND) was assessed with the Shapiro-Wilk test, and the differences according to the ANPg(boolean AND) and the SN(boolean AND)GoGn were estimated using one-way ANOVA. Linear regression analysis was performed to evaluate how the CoGoMe(boolean AND) varied according to age. The statistical significance was set at P < 0.05. The results showed that the CoGoMe(boolean AND) was normally distributed (P = 0.290) with a mean value of 127.2 degrees +/- 7.7 degrees. The distribution of the CoGoMe(boolean AND) in groups with different SN(boolean AND)GoGn angles was significantly different (P < 0.001). These angles showed a positive association (Beta coefficient B = 0.6; 95% CI: 0.51, 0.67; P < 0.001). In growing patients, the CoGoMe(boolean AND) decreased every year by 0.6 degrees (B = -0.6; 95% CI: -1.05, -0.12; P = 0.014). In conclusion, the CoGoMe(boolean AND) was associated with mandibular inclination and could be considered to be a predictor of vertical growth patterns.