The premature loss of primary first molars: Space loss to molar occlusal relationships and facial patterns

Objective:To investigate space changes with the premature loss of primary first molars and their relationship to permanent molar occlusion and facial forms.Materials and Methods:Two hundred twenty-six participants (ranging in age from 7 years 8 months to 8 years 2 months; 135 female, 91 male) met all inclusion criteria designed to study space loss as a result of the premature loss of the primary first molar. After 9 months, space loss was evaluated in relationship to molar occlusion and facial form. Statistical evaluation was performed with the paired t-test and with a two-way analysis of variance for independent groups.Results:Patients with leptoprosopic facial form and end-on molar occlusions all exhibited a statistically significant difference when compared to controls in terms of space loss (P < .001). The mandibular extraction site for individuals with a mesoprosopic/euryprosopic facial form and end-on molar occlusion displayed space loss as well (P < .05). All patients with a leptoprosopic facial form and Class I molar occlusion displayed space loss in the maxilla (P < .05) and the mandible (P < .001) respectively, that was statistically significant when compared to that of the control. Individuals within the mesoprosopic/euryprosopic group and with Class I molar occlusions showed no significant difference in space loss.Conclusions:The relationship between the first permanent molar occlusion and facial form of the child has an influence on the loss of space at the primary first molar site.