Tooth sizes in nonsyndromic hypodontia patients

To evaluate and compare the sizes of teeth in mild and severe hypodontia patients with those of healthy controls.

Dental casts of 154 patients with two or more congenitally missing teeth were obtained. Patients were divided into two groups according to severity of hypodontia. Group I (mild) consisted of 118 patients with two to five missing teeth. Group II (severe) consisted of 36 patients with six or more missing teeth. In addition, a control group was included, which consisted of 50 patients who had an Angle Class I jaw relationship and no missing teeth. Mesiodistal and labiolingual dimensions of the teeth were measured with a digital caliper on dental casts. The independent-samples t-test was used to evaluate the effect of gender on measurements. Intergroup differences for mesiodistal and labiolingual dimensions were evaluated with analysis of variance and post hoc Tukey tests.

Statistically significant differences were found between girls and boys with hypodontia in the mesiodistal dimension of the mandibular first premolar and the labiolingual dimension of the mandibular lateral incisor (P < .01). Mesiodistal and labiolingual width measurements of the teeth of hypodontia patients showed statistically significant differences compared with the control group (P < .05). Most teeth showed significant dimensional reductions in severe hypodontia compared with mild hypodontia (P < .05).

The mesiodistal and labiolingual dimensions of teeth in both mild and severe hypodontia groups were smaller than those in control subjects. The reduction in size was more excessive in the severe hypodontia group. The teeth showing the greatest difference in tooth dimensions were the maxillary lateral incisor (in mesiodistal dimension) and the mandibular canine (labiolingual dimension).