The examinations often were carried out in the oral diagnosis clinics. Family origin, registered in order to determine the Turkish racial composition of the sample, was found to be representative of Anatolian ancestry from the central part of the country. It was identified that the mothers and fathers of all the individuals were Turkish.The following criteria were used for selection of the sample:angle class I occlusal relationship with normal overbite and overjet (overbite < 4mm, overjet < 3mm),well-aligned upper and lower dental arches,normal growth and development pattern,no history of previous orthodontic or prosthodontic treatment,full complement of teeth from second molar to second molar in both arches,no missing teeth, no supernumerary teeth.The sample size was calculated as 142 patients per group, based on a significance level of 0.

05, a power of 80%.Alginate impressions were taken for individuals. The impressions were poured on the same day with hard dental stone. Measurements of all study models were done using a digital caliper with sharpened beaks (accuracy of 0.01mm). Systematic and random errors were minimized by rigidly standardizing experimental equipment and procedures. To determine the errors associated with cast measurements, 25 cast model were selected. Their measurements were repeated 2 weeks after the first measurement and made by the same observer. The landmarks used for measurements were as follows:maxillary interpremolar width: distal pits of the maxillary first premolars,maxillary intermolar width: central fossae of the maxillary first molars.

Mean differences between replicated measurements representing tooth size and arch dimensions were not significantly different from zero. The mean Carfilzomib errors calculated using Dahlberg’s formula [10] ranged from 0.06 to 0.24mm for tooth size measurements and from 0.22 to 0.31mm for arch width measurements. The coefficients of reliability calculated as recommended by Houston [11] ranged from 93 to 99 per cent for tooth width measurements and from 95 to 98 per cent for arch width measurements. These findings indicated that experimental errors were generally small and unlikely to bias the results.2.1. Statistical AnalysisAll statistical analyses were performed using the Statistical Package for Social Sciences (Windows, version 16.0; SPSS Inc., Chicago, IL, USA). Average values, standard deviations, and coefficients of variation were calculated for males and females separately. Incisor and arch widths were recorded for each subject to the nearest 0.01mm according to Pont’s formulae, arch widths were calculated for each subject and the correlation coefficients were calculated between the measured and the calculated arch width values.