Two fundamentally different approaches can be adopted for exploring the impacts of TDIs in children, broadly categorised as quantitative or qualitative enquires. Each has its inherent strengths and limitations, but whichever approach is used, it is paramount that young participants are actively engaged and the questions posed to them are relevant and understandable [10
]. A systematic review conducted in 2014 suggested that investigators who conduct trauma research may have missed opportunities to involve children in the past [11
]. Quantitative research relies on questionnaires or scales, providing numerical data which are conducive to statistical analysis and interpretation but which may fail to uncover novel or more meaningful insights. In contrast, qualitative research seeks to gain a deeper understanding of an individual’s experiences and behaviours using interviews, focus groups or other participatory activities [12
2.1. Findings from Quantitative Research
To date, our knowledge of TDI impacts in children has been largely based on findings from quantitative research. Investigators have used a variety of oral-health-related quality of life (OHRQoL) questionnaires which have been validated for specific age groups and are available in several different languages [9
]. These instruments essentially seek to measure how much a child’s dental condition (e.g. TDI, caries status, malocclusion, dental anomaly) affects them in their everyday life [13
]. The most common response format is to ask children to say how frequently (e.g. in the past three months) they have experienced an impact in order to calculate a total OHRQoL score. Questions typically relate to different domains, such as social wellbeing (e.g. school performance, friendships, smiling), oral symptoms (e.g. pain, discomfort), psychological wellbeing (e.g. self-esteem, confidence) and function (e.g. eating, speaking, sports participation).
The first paper to report on TDI-related OHRQoL in children was published in 2002 [15
]. This was a school-based, cross-sectional study involving 304 Brazilian children aged 12 to 14 years. Following a clinical exam to record the presence of a TDI, caries or malocclusion, children completed the Oral Impacts on Daily Performance (OIDP) questionnaire. Total OIDP scores were adjusted for caries or a malocclusion as potential confounders. The key finding was that children with an untreated TDI were 20 times more likely to report a negative impact on their daily life compared to their peers. Impacts were recorded in all domains, notably affecting smiling, eating and socialising. Since this landmark study, there have been a number of similar investigations in different populations and countries. A systematic review and meta-analysis published in 2018 identified 26 studies which reported on the OHRQoL of children following a TDI, 16 of which related to injuries in the permanent dentition and involved children aged 8 to 15 years [13
]. The studies had been predominantly conducted in Brazil in the period 2011–2015 and involved school-based populations. The key finding was that, despite considerable study heterogeneity, children with a TDI reported significantly worse OHRQoL than their uninjured peers (OR: 1.61; 95% CI 1.16–2.23). Notably, impacts were seen within the social domain.
These cross-sectional studies have provided persuasive evidence that untreated TDIs may have a negative impact on children’s wellbeing as a whole. However, in order to gain greater understanding of what clinical, environmental or personal characteristics may predict OHRQoL within the context of a TDI, more complex study designs and statistical analysis are required. A longitudinal investigation involving 108 children who were treated for a variety of TDIs in a British dental hospital does go some way to meet these criteria [16
]. This study collected personal, clinical and psychometric data, including OHRQoL (from the self-report Child Perceptions Questionnaire) at baseline and at six-month follow-up. Structural equation modelling revealed that girls reported poorer OHRQoL than boys, which is in keeping with findings from other studies [17
]. Good family support and mixed coping styles appeared to be predictors of better OHRQoL and, interestingly, the severity/complexity of the TDI did not directly predict OHRQoL. Put more simply, children with a minor TDI may actually report worse OHRQoL than a child with a complex TDI. Reassuringly, OHRQoL did improve over a six-month period, although some children continued to report specific functional impacts due to eating difficulties. This was attributed to the fact that many of these young patients were wearing partial dentures following tooth loss or experienced repeated failure of large anterior resin composite restorations.