Occlusal changes from primary to mixed dentitions in Nigerian children.

Objective: To evaluate longitudinally the occlusal changes between the deciduous and early mixed dentition stages in Nigerian children.

Materials And Methods: The occlusion of 145 3- to 5-year-old children was initially assessed at a popular pre-primary school center in Ibadan, Nigeria in October 2002, using the Foster and Hamilton criteria. The same group of children was followed up for reexamination in October 2006 in the primary school section of the center. Of 61 students who were located and reexamined, 54 (26 male and 28 female) qualified for the study. The molar relationship was assessed using Angle classification, and other occlusal features such as spacing, crowding, overbite, and overjet were also assessed. Descriptive statistics, chi-square test, as well as Pearson correlation coefficient, were applied as appropriate in the analysis of the data.

Results: Of 32 subjects initially having a flush terminal relationship (Class 1), 22 (68.7%) resulted in a Class I molar relationship, seven (21.9%) had Class II, and three (9.4%) had asymmetric relationships. Mesial step (Class III) was formed initially in 18 and 11 (61.1%) resulted in Class I. A Class III developed in five (27.8%). Significant positive correlations were found for molar relationship, crowding, overbite, and overjet variables (P < .01) between the two periods of assessments, but all were below 0.7 value.

Conclusions: Angle Class I molar relationship was favored by initial flush terminal plane and mesial step relationships in the deciduous dentition.