Evaluation of the effects of permanent tooth agenesis on the maxillary parameters

Introduction
Tooth agenesis, i.e. the congenital lack of tooth buds, is the most common dental abnormality. Depending on the defect severity, there is hypodontia, oligodontia and anodontia.

Aim
The work aimed to evaluate the effects of permanent tooth agenesis on the length of the base and alveolar process of the maxilla and the anteroposterior position of the maxilla.

Material and methods
The study included retrospective analysis of orthodontic documentation, including data obtained from the medical history, clinical examination, assessment of panoramic radiograph and cephalometric analysis based on a lateral cephalogram. The assessment of anteroposterior measurements of the maxilla was based on 13 measurements (9 linear and 4 angular) based on six bone points, six construction points and three construction lines.

Results
A statistical comparison of results of cephalometric analysis in the study group and the control group was performed, and it indicated that agenesis might affect the maxillary parameters. In the study group, a statistically significantly shorter maxilla and the maxillary alveolar process were observed. Moreover, it was observed that the distance of A and Sd points from the points of intersection of a straight line parallel to the occlusal plane, passing through A and Sd points, with the PA line (A’, Sd’) and PM line (A’’, Sd’’) was reduced. Statistically significant more posterior position of the A point and Sd point relative to the ANS point was observed. This study did not show any statistically significant changes in the length of the maxillary base.

Conclusions
Agenesis may affect the parameters of maxillary length and retrusive position of the anterior maxillary outline and apex of the maxillary alveolar process. A congenital lack of permanent tooth buds seems to have no effect on the length of the maxillary base and the anteroposterior position of the anterior nasal spine and the anterior outline of the maxilla relative to the N point.