Factors for crowding in the early mixed dentition stage

Abstract

Objective: To find out the factors responsible for crowding in the early mixed dentition. 
 Materials and methods: 60 dental casts of children in their early mixed dentition ( 30 boys and 30 girls) were divided into crowded and noncrowded groups. Comparison were made between the two groups according to following criterion: -(1) space available for permanent lower incisors, (2) total incisor width, (3) deciduous intermolar width, (5) permanent intermolar width, (6) interalveolar width, (7) total arch length. Correlation of the measurements with crowding was also evaluated. 
 Statistical analysis used: Data was analysed using STATA-12.0 (STATA SE, StataCorp., Texas, USA). Means, standard deviation, and medians were calculated for describing the data. Data was tested for normality using Shapiro-Wilks test. Since all variables were found to be non-normally distributed, therefore comparison of all measurements between the crowded and non-crowded groups was done using Wilcoxon ranksum test (Mann-Whitney test). All values were considered statistically significant for a value of p<0.05.
 Results: Mandibular deciduous intercanine width was significantly larger in Noncrowded Group. The space available for the mandibular permanent incisors and total arch length were significantly larger in Noncrowded Group. The correlation analysis indicated significant correlations between crowding and available space, intercanine width, intermolar width I. No significant correlation was found between crowding and intermolar width II, permanent intermolar width, and interalveolar width. 
 Conclusion: Procedures which preserve the arch length such as timely restoration of proximal caries, prevention of premature loss of deciduous teeth and use of space maintainers such as lingual arch may prove useful in alleviating crowding.