# The effects of professional expertise on perceptions of treatment need in patients with class II division 1 malocclusion: a comparison between orthodontists, general dentists, and lay people in Germany

## TL;DR

This study shows that orthodontists, general dentists, and laypeople in Germany differ in how they perceive the need for orthodontic treatment in patients with certain dental misalignment.

## Contribution

The study reveals how professional expertise influences perceptions of treatment need and facial harmony in class II division 1 malocclusion.

## Key findings

- Orthodontists perceived treatment need at 4 mm overjet, while general dentists needed 6 mm.
- Laypeople did not perceive treatment need at any overjet level.
- Facial harmony perception correlated with treatment need perception across all groups.

## Abstract

This study aimed to compare the perception of practitioners with varying levels of expertise and laypeople regarding the orthodontic treatment need and facial harmony in patients with increased anterior overjet.

Three groups of observers (orthodontists, general dentists, and laypeople, in total n = 48) were asked to rate on images—using a 10-point visual analog scale (VAS)—the facial harmony and treatment need of a sample of 8 patients with class II division 1 malocclusion and overjets of 2, 4, 6, and 8 mm.

Statistically significant differences were observed between the three groups of observers regarding patients with an overjet of 4 mm and above (p < 0.001). Treatment need was perceived at an overjet of 4 mm by orthodontists and 6 mm by general dentists, whereas laypeople did not perceive a need for treatment in any of the groups (p < 0.001). Regarding perception of facial harmony, orthodontists had the lowest threshold (4 mm overjet), while dentists followed at a greater overjet of 6 mm or more (p < 0.001). A statistically significant correlation between the noticed facial harmony and the perceived orthodontic treatment need was found in all observers (p < 0.001).

The perceived orthodontic treatment need for class II division 1 malocclusion increased with increasing professional expertise.