Assessment of curve of spee characteristics across different growth stages in patients with different sagittal skeletal discrepancies

Objective: The aim of this study is to evaluate the changes in curve of Spee characteristics in individuals with different growth periods and different sagittal skeletal development groups using three-dimensional digital models. Method: In this study, three-dimensional study models of a total of 258 individuals grouped as prepubertal (PP2=,MP3=,H1,S) (92 individuals), pubertal (H2,MP3cap,DP3U) (96 individuals) and postpubertal (PP3U,MP3U,RU) (97 individuals) were used. Depths of curve of Spee and dimensional values of arch morphology on digital models of individuals were examined with a model scanning device (3Shape R700 Copenhagen, Denmark) and compared between groups. In two independent group analyses, Mann Whitney U Test was used for normally distributed data and Independent Sample t test was used for data that did not show normal distribution. In comparisons of more than two independent groups, Kruskal Wallis H and One-Way ANOVA tests were used depending on whether the data were normally distributed or not. Results: The mean deepest curve of Spee value on the left side of the arch was found to be higher in the prepubertal group patients than in the postpubertal patients (p=0,003). The depth of the curve of Spee was found to be higher in skeletal Class II patients in all skeletal development groups (p<0.05). Considering all patients, the deepest curve of Spee values of patients in the skeletal Class II group were found to be higher than those of patients in the other two groups (p<0.001). When all patients were compared, the deepest curve of Spee values did not show any significant difference among different skeletal developmental period groups. It was observed that the gender variable did not have a differential effect on the deepest curve of Spee values. Conclusion: It was concluded that while sagittal skeletal anomaly status was effective on the depth of the curve of Spee, the effect of the skeletal developmental period was weak. Key words: Curve of Spee, skeletal development, three dimensional models