Is There a Relationship Between Third-Molar Agenesis and Craniofacial Morphology?

Abstract

Background: Third-molar agenesis is the most common dentofacial anomaly. Therefore, this retrospective study aims to assess the possible association between craniofacial patterns and third-molar agenesis in orthodontic patients.

Methods: A total of 200 patients receiving orthodontic treatment, whose dental records included anamnesis, pretreatment lateral cephalograms, and orthopantomograms, were assessed. Digital cephalometric analyses were performed, and skeletal classes were established using the individualized ANB angle (the angle between Nasion-point A line and Nasion-point B line) and GoGn/
SN angle (the angle between Gonion-Gnathion line and Sella-Nasion line). The identification of third-molar agenesis was facilitated through the use of orthopantomograms. The data obtained in this study were analyzed using the SPSS version 22 statistical software. Chi-square analyses were conducted, and the intraclass correlation coefficient was used to assess intra-observer reliability.

Results: Forty-one cases (20.5%) presented at least 1 third-molar agenesis. The highest number of absent third molars was observed in the tooth number 18, 28, 48, and 38 respectively. The most frequent pattern of third-molar tooth agenesis is absence of 4 (78%), 3 (14.6%), 1 (4.9%) and 2 third molars (2.4%) respectively. There was no significant difference between sexes in terms of agenesis status. Sagittal classification does not have a significant effect on agenesis status. There was a significant relationship between agenesis status and vertical classification. In particular, individuals with agenesis are more likely to have hypodivergent facial type
and less likely to have hyperdivergent facial type.

Conclusion: The tooth with the highest number of agenesis was number 18. Sagittal skeletal classification does not exhibit a significant impact; however, there is a significant relationship between third-molar agenesis and vertical skeletal classification.

Cite this article as: Uslu - Akçam Ö, İbişoğlu GN. Is there a relationship between third-molar agenesis and craniofacial morphology? Essent Dent. 2026, 5, 0038, doi:10.5152/EssentDent.2026.25038