Arch transversal analysis in temporary and early mixed dentition.

Introduction: The analysis and follow-up of dental and occlusal growth and development in children together with the transference of characteristics from one dentition period to another are considered fundamental elements for preventive diagnosis and treatment. The purpose of this study was to determine the changes in the transversal growth that occur between temporary and early  mixed dentition, with the eruption of the permanent first molars.
        Materials and method: A descriptive longitudinal study was carried out in a population of 152 children of both sexes corresponding to the utility period and tooth wear period in temporary dentition and to the beginning of mixed dentition. The transversal variations of such dentitions were considered through measurements obtained from plaster models of bucal impressions from the three dentition periods mentioned.
        Results: By analyzing the changes in the arch, it was determined that there are significant variations (p<0.05) in the transversal measurements according to the type of occlusion, sex and dentition stage (temporary and early mixed dentition). A standard pattern was established to evaluate the arch width between permanent molars at the beginning of the mixed dentition period, and a Temporary Arch index was used to evaluate the correlation between the transversal and longitudinal dimensions in temporary dentition.
                        Conclusion: The evaluation and follow-up of transversal measurements allow early detection of alterations in the arch. There are differences in widths related to the sexes, therefore, we consider it as a variable to be taken into account in the transversal analysis. New indicators (Temporary and Early Arch Index) were established in order to obtain regulations of reference.
                        Key   Words: temporary dentition - mixed dentition - transversal index