Assessing the morphological characteristics of teeth and dental arches as potential predictors of dental crowding.

Background and aims: The early detection of dental crowding and its potential for aggravation is important during the clinical examination of mixed dentition patients, and these desiderates can be addressed by including among the clinically assessed items a series of accessible morphological characteristics of teeth and dental arches. The present study investigates possible correlations between morphological features of permanent teeth, widths of dental arches, and the onset of dental crowding during mixed dentition.

Methods: A selected group of 100 class I dental casts on mixed dentition was analyzed. The dental arches were grouped as spaced, normally aligned, and crowded. The dental parameters consisted of mesiodistal dimensions of permanent teeth and specific morphological features of permanent incisors and first molars. The anterior and posterior arch widths according to Pont indices were measured.

Results: Statistical analysis of data showed that mesiodistal dimensions of the permanent upper central incisors and lower incisors are significantly larger on severely crowded arches than on normally aligned arches; increased differences between mesiodistal dimensions of central and lateral permanent upper incisors and the presence of semi-shavel incisors and Carabelli cusps are associated with a greater extent of anterior crowding. The severely crowded arches presented significantly narrower anterior and posterior arch widths.

Conclusions: Increased mesiodistal dimensions of permanent incisors, the presence of incisors shoveling, the Carabelli cusps on upper first permanent molars, and narrowing of dental arches during the early mixed dentition period were associated with severe dental crowding in class I cases.