Rotaciones de los dientes permanentes en la clínica de ortodoncia

Abstract

lntroduction. The aim of this study is to measure rotation frequency and intensity in upper and lower permanent incisives, permanent canines, and bicuspids, and to relate them to biometric variables such as intercanine and intermolar width, tooth size and arch length discrepancies. Material and methods. Retrospective observation was made using study casts of 50 orthodontically untreated cases selected at random. The presence of all permanent teeth from the first molar to the other was a pre-requisite, as was the absence of agenesis or supernumerary. Measurements of the rotation of each tooth, mesiodistal diameter, intercanine and intermolar width, and upper and lower arch length discrepancies were taken. The statistical analysis consisted of determining mean, standard deviation, with a 95% confidence interval for the mean of the values under study; Student T test and ANOVA using Tukey test to compare 2 and 3 means respectively; and r-Pearson correlation coefficient. Results. The percentage of rotated teeth for each type fluctuated between 48% and 82% with no statistically significant differences between them being found, except for teeth 3.3 and 4.3, which revealed significantly higher frequencies than the remainder, 80% and 82% respectively. No sexual or bilateral dimorfism were found. No significant correlations between rotations and biometric variables were found, except for upper arch length discrepancy with a negative value and the number of rotated teeth in the upper arch (r=-0.327;p<0,05).