## 4 Discussion
Similar results were published by other authors: [PERSON] and co-workers conducted a study on 104 patients with permanent dentition arches (50 patients with gross dental crowding and 54 patients with little or no crowding) and concluded that the crowded group presented significantly smaller arch dimensions than the non-crowded group [12]. [PERSON] et al. published the results of a retrospective study including 23 patients with primary dental arches (12 normal and 11 crowded cases). They concluded that the primary dental arch lengths of the subjects in the normal group tended to be larger than those found among the subjects in the crowded group [30]. The study conducted by [PERSON] et al. on a sample of 150 students from Peru tried to determine which intra-arch occlusal variables are the best discriminators for dental arch crowding in the permanent dentition [31]. The results of the cited study showed that arch length is the most important individual factor for crowding in permanent dentition. A study in a Southern Indian population aimed to evaluate dental crowding in relation to the meso-distal crown widths and arch dimensions and analyzed 132 CT scans of adult patients (genders equally represented, half crowded and half non-crowded), [32]. Its conclusions showed that in males, crowded dentition had statistically significantly larger meso-distal tooth size and smaller arch dimensions; in females, the results were not statistically significant. Our results sustain the hypothesis that dental crowding is frequently associated with smaller dental arches, so more attention should be paid to methods of increasing the size of dental arches. This is especially relevant in young patients with mixed dentition, when treatment modalities may include methods to stimulate the development of the jaws in order to properly align the teeth. Related to teeth dimensions, the statistical analysis was performed separately for each gender; half of teeth diameters presented statistically significantly larger values in male than in female patients, regardless of crowding status. These gender disparities on crown dimensions are in agreement with previous studies [33]. The results of our research showed that the meso-distal dimensions of upper central incisors were statistically significantly larger in female patients with severely crowded maxillary arches than in those with spaced ones, and the meso-distal dimensions of lower lateral incisors were statistically significantly larger in male patients with moderately or severely crowded mandibular arches than in male patients with normally aligned lower arches. Analyzing the meso-distal dimensions of upper first permanent molars, the results of our study were not statistically consistent, probable due to the relatively small sample size. These results partially confirm some previously published data: a study conducted in India on a group of 90 patients aged 12-18 years and divided into three groups (no dental crowding, mild crowding, moderate crowding) identified that the coronary proportions differed significantly between the three groups only for the central maxillary incisor. Therefore, the authors concluded that the coronal dimensions of the central maxillary incisors are largely responsible for the variations observed in the analyzed dental crowding cases [34]. The study conducted by [PERSON] and [PERSON] also points to a causal relationship between the incisors' coronary proportions and crowding, in a proportional sense (the larger the size of the incisor crown, the greater the degree of dental crowding) [35]. The research conducted by [PERSON] on a study group comprising 60 British boys and 60 Pakistani immigrant boys found no relevant correlations between specific mesio-distal teeth dimensions and dental crowding [14]. However, the author stated that in combination with other parameters, the meso-distal dimension contributes significantly to the total regression equation.