Aim: The aim of this study was to establish a specific proportional correlation method for space analysis in mixed dentition applicable to the Italian population.
Materials and methods: A retrospective analysis was performed on 300 plaster models taken from Italian subjects, 156 females and 144 males, aged between 12 and 25 years, visited at the Department of Orthodontic and Paediatric Dentistry of the University of Messina.
Results: The variance analysis (ANOVA) showed a high correlation between the dimension of the mesio-distal diameters of the four mandibular incisor and those of the upper canine and premolars. The correlation coefficient showed the existence of a directly proportional, positive intra- dependence between the two groups.
Discussion: The correlation tables used in the present study appear to be much more accurate if applied to groups of patients with similar ethnic backgrounds, thus explaining the differences between the various prediction indexes found in previous publications.
Conclusion: This study highlights the need to develop specific values to fit the features of the different ethnic groups.