Hypodontia of Maxillary Lateral Incisors

 Hypodontia, also known as tooth agenesis, is a frequent variation found in dental development and could occur as a part of a syndrome or in a nonsyndromic form. Genetic factors are a major component of the formation of these teeth in terms of size and shape. This particular study focuses on a specific variant of MSX1 (MSX1 rs8670). A sample of patients with isolated, maxillary, lateral incisor agenesis and matched controls had the measurements and morphology of their teeth noted. The methods of this analysis were: genotyping the MSX1 rs8670 genetic variant and morphometric measurements with a 2D image analysis. They were both performed for 26 hypodontia patients and 26 matched controls. This genotyping showed that the presence of the T allele increased the risk of upper lateral incisor agenesis to about 6.9 times the risk of individuals without the allele. There were also easily identifiable morphological differences between hypodontia patients and controls and between the unilateral and bilateral agenesis cases. Of all the teeth affected by hypodontia, the crown of the bucco-lingual dimension was the most affected. There was also evidence indicating that there was significant variation in the crown shape with the Carabelli trait of the upper first molars. The overall findings conclude that the MSX1 rs8670 variant does have associations with variations of the morphological outcomes in dentition. However, epigenetic and environmental factors interact with this variant to cause the variation in morphology, not just the variant itself.

The article highlights how genetics is intertwined with environmental factors, creating variation in morphology; in this case, specifically teeth. This demonstrates that a reliance on a singular factor for an outcome is not very common. Further linking of factors are needed to truly understand the observable traits in an individual, beyond just one or the other. I find the results of this analysis to be a beneficial supplement in studying similar variants in dentition in future analysis.

Link to the article “Genetic and Morphological Variation in Hypodontia of

Maxillary Lateral Incisors”: https://doi.org/10.3390%2Fgenes14010231

another related article: https://doi.org/10.1177/154405910808700715