Prediction of unerupted canines and premolars in a Syrian sample

Abstract

BackgroundThe current study aimed to evaluate the applicability of the methods of Moyers and of Tanaka and Johnston to estimate the mesiodistal widths of permanent canines and premolars in Syrian individuals, to determine whether the predicting equations differ by sex, and to develop more accurate regression equations using various teeth groups as predictors.MethodsA total of 670 pretreatment pairs of casts belonging to 342 female patients and 328 male patients were selected from the archives of orthodontic clinics in Damascus University and Al-Baath University. All relevant teeth were measured to the nearest 0.01 mm. Paired t tests were used to test the applicability of the Moyers method and the Tanaka and Johnson equation on Syrian individuals. New regression equations were constructed.ResultsThe predicted values of permanent canines and premolars derived from Moyers' charts at the 50th percentile levels tended to underestimate the actual values for the male subjects but were comparable to the actual values for the female subjects. However, the predicted values derived at the 75th percentile levels tended to be comparable to the actual values for the male subjects and to overestimate the actual values for the female subjects. The predicted values calculated by Tanaka and Johnston's equations tended to overestimate the actual values in both study groups.ConclusionsThe Moyers method was more accurate for the mixed dentition analysis for Syrian individuals. However, the proper percentile level is determined by sex. The use of the equations constructed using the Syrian sample is advised.

Applicability of bolton’s tooth size ratios among mediterranean, japanese and japanese-brazilian populations

“…There were no significant systematic errors, and the random errors of the mesiodistal diameters of each tooth were within acceptable limits 14,15 , ranging from 0.10 (canines) to 0.31 mm (molars).…”

Evaluation of two methods for mixed dentition analysis using the method error

“…Previous studies, comparing methods in which X-rays are not used, showed variable results when assessing different methods of mixed dentition analysis for different populations 11,[16][17][18][19][20][21] . The differences in the ethnic origin of the samples and the methods of measurement may explain these findings 16 .…”

“…However, these methods are less practical, because they are more expensive and require more time and specific equipment. These facts may explain why most researches compared methods based on tables to perform the mixed dentition analysis 11 . In contrast, the present study aimed to compare the reliability of two methodologically different methods, one that uses periapical x-rays and another that uses mathematical equations to predict the MD width of unerupted permanent canines and premolars, in order to identify which one has higher reliability, by assessing the method error.…”

“…This difference in tooth size can be used to prevent or intercept future malocclusions 8 . The most commonly used tests are divided in two groups: those using mathematical equations that can generate tables and those using radiographs to assess the size of the unerupted teeth 1,2, [9][10][11] . The decision on the appropriate method to be used for each patient depends on certain circumstances.…”

“…On the other hand, methods using radiographs have been considered more accurate, but also less practical, more expensive, more time-consuming and require specific equipment 11 . Comparing these two methods for estimating the MD width of unerupted permanent teeth in the mixed dentition analysis, this study aimed to determine which one is more reliable, by assessing the method error 13 .…”