Are dentofacial features and bullying associated with self-harm?

Occasionally a paper is published that really makes you think. This research looked at the association between dentofacial features and self-harm. It brought a troubling relationship into focus for me. All dentists and orthodontists should be aware of this research.

The authors of this paper did a comprehensive literature review, and I have made this list of what I felt were the most critical points about self-harm.

• Self-harm is any behaviour that causes poisoning or injury.
• It is an expression of distress associated with stressful life problems.
• The onset age for self-harm behaviour is between 12-14 years, which peaks at 15-17 years old.
• Prevalence is reported as 7.5%-46.5%.
• Bullying is highly associated with self-harm.
• Bullying may have a relationship with dentofacial features.

As a result, there may be an association between dentofacial features and self-harm.

What did they ask?

They did this study to ask the following questions.

“What is the prevalence of self-harm among eight grade children in Amman, Jordan”?

“Is there an association between dentofacial appearance on self harm and bullying”?

“Is bullying because of dentofacial appearance related to self-harm”?

What did they do?

In the first part of the study, the team identified and approached a representative sample of children to find out if they could participate in the survey. They did this in several stages; these were:

First, the team randomly selected 23 schools, stratified by gender, from Amman.

Next, they asked School principals if they could participate in the study.

Consent forms were then sent to the parents of children in the eighth grade.

If the parents consented, they gave anonymous questionnaires to the children to complete in school without any assistance.

The questionnaire included sections on demographics. This was followed by a question on whether the child self-harmed. If they did, they asked if this was this was due to dentofacial features and the nature of these features. Finally, they recorded if the self-harm was due to being bullied about dentofacial features.

Importantly, they did not examine the participants. I will discuss this later.

Finally, they analysed the data with complex and relevant statistics.

What did they find?

They produced a large amount of data with a very detailed data analysis. These were the main points that I identified.

The sample comprised 699 students who had a mean age of 13.3 years.

• 9% reported self-harm
• 9% reported bullying
• A total of 90 (12.9%) reported self-harm because of facial features.
• 41 (5.9%) stated that they self-harmed because of bullying targeted at their facial features.

The data analysis suggested that.

• Self-harm was strongly related to reported dentofacial features and being bullied about dentofacial features. These reported features included prominent teeth, crooked teeth, prominent mandible, missing teeth, and a gap between the front teeth.
• The total effect between dentofacial features and self-harm was statistically significant. However, bullying did not mediate this effect.

Their overall conclusions were;

• There is a relatively high experience of self-reported self-harm in this population of children.
• The relationship between self-harm and dentofacial features was not mediated by bullying.
• Self-harm because of dentofacial features represented almost half (47.9%) of those subjects reporting self-harm.
• The most common dentofacial features contributing to self-harm were tooth colour and shape, spacing or missing teeth, and prominent maxillary anterior teeth.

What did I think?

This was a very complex paper to interpret, and I hope that I managed to do this. Before I discuss the findings, it is worth looking at possible shortcomings. However, the authors have done an excellent job of identifying these. Firstly, the study is a retrospective self-report design. This means that the children would have to remember their experiences. This does lead to some recall bias. However, it was good to see that the questionnaires were completed without input from their parents or teachers.

We also need to consider that the study was cross-sectional. We would get more information if this was a longitudinal design in which features of malocclusion and even the effect of orthodontic treatment on self-harm were recorded.

The method of generating the sample was suitable and selected a random group of subjects. However, I was a little concerned that there was no record of the subject’s dentofacial features. Nevertheless, the children reported their perceptions of the target of bullying, reflecting the “real world” of childhood interactions.

I thought that the association between dentofacial features and self-harm was compelling, even though the proportion of the total sample was small at 6%. Nevertheless, this does not diminish the importance of this association.

Final comments

I am not an expert on this type of research, and I rely on my limited population-based study knowledge. However, I cannot help feeling that these findings are significant, and they do add to our understanding of the potentially harmful effect of concern about dentofacial features. Therefore, I suggest you read this paper, although it is behind the AJO paywall.

Kevin O'Brien

Emeritus Professor of Orthodontics, University of Manchester, UK.