Dr Guy Willems and his colleagues at KU Leuven have conducted research to tackle this problem. Their recent clinical trial explored how early interventions in mixed dentition can guide upper canines into their proper positions, reducing the need for extensive orthodontic treatment and invasive procedures later.

The trial included 76 children with at least one impacted canine and limited space in the upper jaw. The children were divided into groups. In one group, removable plates (with acrylic coverage of the teeth) were used to gently widen the upper jaw through a process called slow maxillary expansion. This involved turning a small screw on the plate by one-quarter rotation each week to gradually expand the jaw. Once the desired expansion was achieved, the plates were worn full-time for three months, followed by another three months with the plates adjusted to remove the acrylic coverage. Another group had their baby canine teeth removed, while a third group received no treatment. A fourth group, with enough jaw space, served as an external comparison.

Over 18 months, Willems and his colleagues tracked how the children’s canines moved using dental X-rays. They found that slow maxillary expansion was particularly effective, significantly improving the positions of impacted canines in relation to neighbouring teeth, compared to the removal of baby canines or no intervention.

Up to 60 months later, children who had undergone slow maxillary expansion also required significantly fewer major orthodontic procedures. In fact, their outcomes were comparable to those of the fourth group who had sufficient jaw space.

While extracting baby canines helped improve the adult canines’ angle to the midline, it did not perform as well as slow maxillary expansion. The children with limited jaw space who received no intervention typically saw their condition worsen, with canines becoming more difficult to manage over time.

Willems emphasises that early detection is key. A simple panoramic radiograph taken at the age of 8 or 9 can identify potentially impacted canines and guide timely treatment decisions, by simply looking at the canine’s angle to the midline, which should be below 15°. His team’s research highlights the value of slow maxillary expansion as a preventive measure, offering a less invasive and more effective approach to managing canines prone to impaction.

Thanks to this research, dentists now have evidence-based strategies to guide their young patient’s dental development toward better outcomes.