The Evolution of Dental Crookedness

The intriguing discovery within the fossil record has unveiled a remarkable fact: our ancestors possessed perfectly aligned teeth, including wisdom teeth, without ever undergoing orthodontic treatment. This revelation raises the question of why modern humans commonly experience dental issues that necessitate the use of braces and wisdom tooth extraction, which seem to be recent phenomena in comparison.

While it is challenging to ascertain the exact cause of this disparity, scientists have put forth a compelling hypothesis. Several million years ago, our early ancestors led a subsistence lifestyle, where their teeth and jaws were subjected to rigorous tasks of breaking down the food they consumed. The evidence supporting this notion lies in the extensive wear and flattening of tooth surfaces, which indicate the demanding nature of their diet. Additionally, their jaws and teeth were larger, reflecting the functional requirements of their food processing endeavors.

As time progressed, these early humans began to utilize tools and discovered the benefits of cooking with fire. These advancements in technology revolutionized the way food was prepared and consumed, facilitating a more efficient breakdown of nutrients. However, it was around 12,000 years ago that a significant shift occurred, with the advent of agriculture and the domestication of animals and plants. This transformation marked a turning point in human habits and initiated a cascade of changes in our diets.

Over thousands of years, the practice of food processing and refinement became increasingly prevalent. Notably, the industrial revolution propelled these processes to unprecedented levels. Consequently, within a relatively short span of time, many individuals were relieved of the arduous grinding and crushing duties that their mouths had previously endured. Intriguingly, this coincided with an apparent increase in tooth misalignment.

By examining fossils spanning millions of years, researchers have observed a gradual decrease in tooth and jaw size in humans and our ancestors. In the past, dietary shifts occurred gradually, allowing changes in tooth and jaw size to keep pace. However, the recent agricultural and culinary revolutions disrupted this equilibrium. According to the prevailing theory, certain human populations experienced a rapid reduction in jawbone size, while teeth remained relatively large, resulting in limited space within the oral cavity. Consequently, emerging teeth began to displace others, leading to unconventional positions and misalignment. Furthermore, wisdom teeth, which typically emerge last, often lacked sufficient space, resulting in impaction and the subsequent discomfort and infections commonly associated with them.

This research suggests a strong correlation between larger jaws and the demands of chewing. As human diets became less reliant on tough, fibrous foods, jaws gradually decreased in size, leading to dental crowding and misalignment, as well as complications during wisdom tooth eruption. While this hypothesis finds support in preliminary experimental data, it posits an environmental or lifestyle cause rather than a purely genetic one, although heritable factors may still play a role in certain cases.

Tooth crowding affects a significant portion of the population today, with estimates ranging from 30 to 60%, albeit with variations across different global populations. Some individuals naturally lack wisdom teeth or experience tooth crowding even in the absence of complications during wisdom tooth eruption. This correlation appears to align with diets that are less reliant on processed foods and more in line with the natural diets of our ancestors.

Given this information, it begs the question: Can tooth crowding be prevented or mitigated through lifestyle changes and orthodontic interventions? This inquiry poses an important topic worthy of thorough consideration. By understanding the underlying causes of dental misalignment and exploring potential preventive measures, we may be able to improve oral health outcomes and reduce the need for orthodontic interventions in the future.

Henrik Leandro