Does dental appearance impact on employability in adults? A scoping review of quantitative and qualitative evidence

AbstractBackground: The importance of physical appearance in social and professional situations has been well studied. It has been suggested that improving dental appearance may increase employment prospects. This scoping review aims to map the current literature regarding the impact of dental appearance on employability.

Methods: A scoping review was carried out in accordance with guidance from the Joanna Briggs Institute. Inclusion and exclusion criteria were developed iteratively, databases were searched and decisions on inclusion made in duplicate. Data were charted in Excel and synthesised using a visual map, study summary table and narrative description.

Results: We identified 16 relevant articles: 10 experimental simulation studies, 2 qualitative studies, 1 cross-sectional survey, 1 pre/post dental treatment survey, 1 retrospective cohort study and 1 narrative systematic review. Experimental simulations support the notion that visible dental conditions can negatively impact appraisals of employment-related personal characteristics. Negative impacts on job-seeking self-efficacy and willingness to apply for jobs have also been documented.

Conclusions: The applicability of this evidence-base to the UK health-system context is uncertain and demonstration of real-life impact on employment is lacking. Further research is needed before programmes to improve dental appearance could be justified on the basis of improving employment outcomes.

Word count: 198

In brief

Maps the existing literature on the link between dental appearance and employability

Identifies where there are gaps in the literature and makes recommendations for further research

Questions the NHS definition of “clinically necessary” dental treatment

Background

Healthy teeth are not only a vital component in maintaining good health, but they also make a significant contribution to physical appearance. There is abundant literature demonstrating that ratings of personal characteristics such as competence, intelligence and trustworthiness are influenced by facial attractiveness.1–3 Such judgements have been shown to take place in as little as 100 milliseconds, below the threshold of conscious awareness.2 Furthermore, attractiveness has been shown to influence judgements regarding suitability for employment, particularly for consumer facing roles.4–6 Smiling has been shown

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to increase positive ratings of characteristics including agreeableness, trustworthiness and intelligence, and the negative impact of not smiling may be greater for women than men.7–9

Oral health in developed countries has drastically improved over the last 50 years.10,11 Alongside these improvements, patient expectations and social norms around what is an acceptable dental appearance have also changed.12 In the past, missing, discoloured, or misaligned teeth were as acceptable as they were common.12 In more recent times, television make-over programmes, social media and advertising have all been credited with changing attitudes towards what is an acceptable dental appearance.13–15 What may have once been termed the “Hollywood Smile” has become increasingly transatlantic; cosmetic dentistry was the most desired non-surgical cosmetic treatment among U.K. adults in 2018.16 Straight, white teeth are a prominent outward-facing display of social and economic capital; a signifier of class, self-control and success.15

Poor dental appearance may negatively impact employment opportunities through a variety of mechanisms. Fifteen percent of adults in England, Wales and Northern Ireland report difficulty smiling or laughing without embarrassment because of their teeth.17 Nearly 18 percent of US adults have reported that the appearance of their mouth and teeth affected their ability to interview for a job; increasing to 29 percent for those in low income ‐households.18 Reduced ability to speak and smile confidently, combined with expectations of negative appraisals could hinder performance at interviews.19 Furthermore, interviewers may make less favourable judgements of ability based solely on appearance, because of conscious or sub-conscious biases. Social differences in oral health are more likely to be explained by attributing blame to poor ‘lifestyle choices’ than for other conditions such as diabetes or cancer.20 This is despite abundant evidence that the greatest contributors to inequalities in health and oral health are environmental, rather than behavioural.21

Stable employment is beneficial for the individual and society; long-term unemployment increases the risk of depression, cardiovascular disease events and all-cause mortality.22 At present ‘return to work’ support programmes in the UK23 do not include supported access to dental care, but this is something that has been examined in other countries.24 This scoping review aims to map the current literature regarding the impact of dental appearance on employability and identify areas for future research.

Methods

Scoping reviews are used to map the existing literature on a particular topic, to identify the number and types of studies available. They are particularly useful where the body of literature is complex and varied, or where a systematic review with precisely defined apriori inclusion criteria could result in an overly narrow pool of evidence. This scoping review has been carried out in accordance with the guidance produced by the Joanna Briggs Institute25 and is reported following the PRISMA extension for scoping reviews (PRISMA-ScR).26

The research questions of interest were:1. Does poor dental appearance negatively impact employability in adults?2. Can dental treatment improve employment outcomes?

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We developed a protocol in advance, which is available on request from the corresponding author. The searches were undertaken iteratively, in September 2019. Firstly, a broad search was undertaken using Google and Google Scholar, to identify grey literature and scope out the potential numbers of studies and the types of journals they were found in. The search terms used were (dental appearance / oral health / dental treatment) and employment). Secondly, a database search using PsychINFO, Social Policy and Practice, Embase and Medline, via Ovid was carried out using the following search terms (worklessness OR job OR employment OR employability OR unemployed) AND (dental treatment OR oral health OR dental appearance OR dental attractiveness OR smile). Informed by the terms found in some the identified studies, a further search was carried out replacing the employment-related terms with (social perceptions OR social judgements).

Studies were limited to human, English language and from 1980. The authors did not have the capacity to translate other languages and we felt that prior to 1980 social norms around appearance may not be relevant for today. We placed no restriction on study type. The reference lists of the retrieved full-text articles were scanned for further relevant studies.

Titles and abstracts were screened and assessed in relation to the following inclusion and exclusion criteria:

Participants aged over 16 Studies investigating the relationship between dental appearance, dental treatment

or oral health and employment Studies investigating the relationship between dental appearance and judgements of

employment suitability Studies investigating the relationship between dental appearance and judgements

about personal characteristics related to employment, for example intelligence. Studies concerning purely aesthetic judgements, extra-oral cranio-facial conditions,

and orthodontic appliances were excluded.

Studies identified as potentially relevant for inclusion were obtained in full-text and reviewed by DM and RK to inform the final decision. Data charting / extraction was carried out in Microsoft Excel, under the following headings: Study reference, study type, aim, country, participants, sample size, intervention or exposure, comparator group, outcomes used, key findings, authors conclusions, reviewers’ conclusions. The data charting was completed by DM and cross-checked for accuracy by RK. Due to the heterogeneous nature of the included studies, and in common with most exploratory scoping reviews, we did not undertake a formal critical appraisal of each individual study.25

Results

A PRISMA flowchart illustrating the iterative search is process provided in Figure 1.

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Figure 1 PRISMA flow diagram for the scoping review

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After completion of data charting, we synthesised the results by creating a study summary table (Table 1) and a visual map of how the studies related to each research question (Figure 2). Studies represented with a green circle provided supportive evidence in response to the research question. Studies represented by a red circle provided evidence of a negative or equivocal response to the research question. The number within the circle relates to the number of studies. The study summary table (Table 1) and the visual map (Figure 2) informed the narrative synthesis which is presented below in response to each research question.

Table 1 Study summary table

Country, citation and year

Study design Dental conditions investigated

Employability-related outcomes

Key findings

Brazil, 27

2014

Experiment using modified photographs

Malocclusion Hire-ability, honesty, intelligence, efficiency at work

Ideal smiles perceived as more intelligent and more likely to be hired than those with malocclusion. No significant differences were found for honesty and efficiency

UK, 28

2018

Experiment using modified photographs and CVs

Fixed appliances, missing lateral incisor

Interview shortlisting, expected performance in earning commission

Dental appearance did not influence employability-related perceptions when combined with CVs

US, 29

2019

Cross-sectional epidemiological

Dental Problem Index: Score of anterior missing teeth, untreated caries, white spot lesions

Probability of being currently employed

Reduced probability of being currently employed with increased number and severity of visible dental conditions.

Canada, 30

2018

Qualitative interviews with recipients of dental treatment

Pain, ability to eat, sleep

Confidence, self-concept and self-perceived employability

Participants reported feeling more confident to apply for jobs and attend interviews after dental treatment: “So yeah, I’m optimistic now — more than I would have been — to be able to interview properly and give it my best shot.”

US, 31

2016

Qualitative interviews with prisoners

Pain, swelling, missing teeth, decayed teeth

Stigmatization and self-perceived employability

Participants felt that poor oral health would impact on post-release employment prospects: ‘‘Would you hire me? Would you really hire a guy who looks like me?’’

UK, 32

2003

Experiment using modified photographs

Cavitated caries, stained dentine, pulpal

Perceived intelligence, success and

Participants judged photographs modified to show dental disease less favourably than unmodified

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necrosis education level images UK, 33

2001

Experiment using modified photographs

Cavitated caries, stained dentine, pulpal necrosis

Perceived intelligence, success and education level

Participants viewing the images rated those with decayed or discoloured teeth as less intelligent, less successful and less likely to have attended University

Israel, 34

2001

Experiment using modified photographs

Untreated caries

14-character traits related to professionalism, e.g. intelligence, education, laziness

Participants consistently rated those with an intact dentition more favourably than those with caries or discoloured teeth.

Spain, 35

2014

Experiment using modified photographs

Tooth shade Perceived intellectual ability, academic performance, trustworthiness, friendliness

Participants rated lightened teeth more favourably than natural teeth, which were rated more favourably than darkened teeth.

UK, 36

1985

Experiment using modified photographs

Malocclusion Friendliness, intelligence

Participants rated those with malocclusions as significantly less friendly and intelligent.

UK, 37

2008

Experiment using modified photographs

Natural teeth, whitened teeth and untreated caries

Perceived intellectual ability, social competence

Participants rated images showing whitened teeth most favourably, followed by intact natural teeth, then carious teeth.

UK, 38

2006

Experiment using modified photographs

Normal enamel, mild fluorosis, severe fluorosis, caries

Intelligence, reliability, sociability, carefulness

Severe fluorosis and to a lesser degree, untreated caries were rated significantly less favourably than normal enamel. Mild fluorosis was rated the same as normal enamel.

UK, 39

2006

Experiment using modified photographs

Normal enamel, mild, moderate and severe fluorosis

Intelligence, sociability, reliability

Participants asked to pay attention to the mouth rated more severe fluorosis less favourably. If shown extra-oral images without being cued to look at the mouth, the ratings did not vary with fluorosis severity

Canada, 40

2013

Narrative systematic review

Receipt of dental treatment

Self-perceived employment prospects, leaving welfare program, employment, earnings

Little evidence available, all 7 included studies were judged to be at high risk of bias and only 3 had any comparator

Canada, 41

2015

Uncontrolled pre/post dental treatment surveys

Receipt of mostly urgent dental care or dentures

Job-seeking self-efficacy score (JSSE)

Dental treatment significantly improved job-seeking self-efficacy score

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Canada,

42

2016

Retrospective cohort

Receipt of dental treatment

Leaving employment assistance program

Employment outcomes of those who received dental treatment were not significantly different to those who did not receive dental treatment

Figure 2 Visual map of how the identified studies relate to the research questions

1. Does poor dental appearance negatively impact employability in adults?

Three studies specifically investigated the impact of dental aesthetic conditions on employment or suitability for employment.27–29 One cross-sectional study investigated the association between an individual’s number and severity of aesthetic dental conditions (measured using a “Dental Problem Index”) and current employment status.29 The authors found that a one-point increase in the Dental Problem Index was associated with 7.70 percent (CI: 5.15–10.19%) lower odds of being employed, after taking account of age, gender, marital status, years of education, poverty level and health status.29 Two experimental studies modified photographs to illustrate dental aesthetic conditions and asked participants to make judgements about the subjects’ employment prospects.27,28 Pithon et al. found that perceptions of hire-ability and intelligence were negatively impacted by malocclusion, whilst those of honesty and work efficiency were not.27 In a similar study where photographs were also accompanied by a curriculum vitae (CV), no significant impacts were observed on the likelihood of shortlisting for interview or expected performance in earning commission.28

Two qualitative interview studies identified themes related to the impact of poor dental appearance on employment prospects.30,31 Douds et al.31 interviewed 30 US adult male parolees about their experiences of prison dental care. Kerr 30 interviewed six recent

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patients of a dental outreach organisation about the impact of the dental care they had received. Participants felt that their poor dental appearance was assumed to be related to past or current drug use,30,31 likelihood of re-offending,31 and expectations of needing time off from work to attend dental appointments.31

The social disadvantage incurred by not smiling was raised as a barrier to employment in both studies.30,31 A particularly impactful quote is reproduced below:

"They kept telling us in a job training class that we need to look like the job we want ... ‘‘dress for success.’’ Ha! You can put me in an Armani suit, and I still won’t have any teeth." 31

The majority of the studies that we identified in relation to this research question assessed the impact of aesthetic dental conditions on perceptions of work-related character traits.32–

39 Whilst these studies did not specifically set out to explore the relationship between dental appearance and employability, they were included because they contribute towards the theoretical and conceptual basis for such a relationship. All of these studies found that images which had been modified to illustrate aesthetic dental conditions received less favourable judgements compared to unmodified dentition. A large variety of conditions were tested: Caries,32–34,37,38 stained dentine,33 pulpal necrosis,32,33 tooth shade,35,37 malocclusion,36 and fluorosis.38,39 The types of characteristics that were perceived more negatively included: intelligence,32–39 education,33,34 trustworthiness,35 laziness,34 reliability,38,39 sociability32,37–39 and friendliness.32,35

2. Can dental treatment improve employment outcomes?

All of the studies of relevance to this research question were conducted in Canada.30,40–42

A systematic review included seven heterogeneous studies and concluded that there was little evidence to suggest that dental care could improve employment outcomes and the available studies were of poor quality, with the majority lacking a comparator group.40 A large retrospective cohort study using administrative data42 investigated if recipients of an employment-assistance programme who utilised the offer of free basic dental care were more likely to leave the programme than those who did not. The authors found that employment outcomes were not significantly different 12 months after receiving dental care.42

A small pilot study found that the ‘job-seeking self-efficacy’ of the 31 participants increased one month after receipt of public dental care, which consisted mainly of urgent treatment and / or dentures.41 This self-reported increase in willingness to apply for jobs was also raised in one of the qualitative interview studies.30 The participants felt that the dental treatment they had received had improved their job prospects by increasing their self-confidence and willingness to make applications and attend interviews:

“Prior to having the dental work done, I would not have had any vested interest insending out resumes or making appointments for job interviews. Now, I send out my resume. I don’t

have a problem going to meet with anybody.” 30

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Discussion

This study aimed to identify and the map the existing literature regarding the impact of dental appearance on employability and to identify gaps in the evidence-base. The search revealed a diverse array of study types, although relatively few that directly addressed both dental appearance and employment.27–31 All but one28 of those studies provide some evidence to support the notion that dental aesthetic conditions may negatively impact employment outcomes or employment prospects.27–31 Similarly, the studies which measured the impact of dental appearance on perceptions of work-related personal characteristics, all reported negative impacts.32–39 This finding aligns with existing research on facial attractiveness, which has demonstrated that the stereotype that “what is beautiful is good”3 holds for a range of characteristics, particularly social competence and intelligence.43,44 However, despite the number of studies which suggest that poor dental appearance can negatively impact employment-related outcomes, 27–39 only one45 of the three studies which specifically investigated the impact of dental treatment on employment-related outcomes reported any evidence of benefits.40–42 Furthermore, the benefits of dental treatment that were reported related to intermediate steps of increased confidence and ability to apply for jobs, rather than actually becoming employed.30,31,41

A strength of this review was the scoping review methodology, which allowed for a broad consideration of the evidence base around this topic. If we had limited the review strictly to the highest levels of evidence suitable for this research question, we would have found very little to learn from. The qualitative interview studies in particular provided rich insight into how poor dental appearance may hinder job-seeking, but unfortunately we did not identify any that were carried out in the UK context.30,31 The systematic search strategy and large range of databases searched were also strengths, although the majority of studies were identified through the Medline database. Limitations are that studies were restricted to English language because of a lack of translation facilities and the review protocol was not registered, as we were unaware of a suitable repository at the time. We have since learned that The Centre for Open Science hosts a publicly available repository which we would utilise in future.46

In accordance with guidance on scoping reviews, we did not undertake any formal assessment on the quality of the included studies. However, the majority were experimental simulation studies using modified photographs.27,28,32–39 How well these reflect judgements made in real-life social situations is unknown. It has been shown that viewing distance and being asked to look specifically at teeth can affect judgements of dental aesthetic conditions.39,47 Many such photograph-based studies have also demonstrated that the social judgements made are affected by characteristics of the judge themselves, such as: age, sex, ethnicity, 27,48,49 actual and self-perceived attractiveness50,51 and intelligence.51 Many of the included studies did not adequately control for these variations in the perceivers themselves, because they used different groups to judge different sets of images.

Epidemiological observational29 and intervention40,42,45 studies provide a more robust level of evidence than experimental simulations and the findings of these were mixed. Furthermore, applicability to the UK context is uncertain, as all of the studies were conducted in countries where dental care is funded either by the individual or through

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private insurance. 29,40,42,45 In the UK, the partial funding of dentistry through the National Health Service (NHS) means that for adults receiving certain employment, disability, or low-income related benefits, dental care is provided free of charge.52 For those not receiving benefits, dental care is subsidised. Despite these provisions, cost is cited as a barrier by 20% of adults from routine and manual occupations53 and people experiencing homelessness report multiple barriers to accessing NHS dental care.54

Two studies35,37 reported positive benefits of a lighter tooth shade on perceptions of character traits related to employability (intellectual ability,35,37 academic performance, trustworthiness, friendliness,35 and social competence37). The scope of NHS dentistry is broadly defined as any treatment that is “clinically necessary” to maintain good oral health, as opposed to purely cosmetic treatments such as tooth whitening.55 Despite this, it is accepted that the majority of NHS orthodontic care delivers aesthetic, rather than functional improvements.56 This is justified by evidence that social wellbeing is improved by correction of malocclusion.56,57 This more holistic view of health aligns with the World Health Organisation definition, agreed in 1948, which frames health as “complete physical, mental and social well-being and not merely the absence of disease or infirmity”. The complex relationships between social judgements, psychological well-being, social inequalities, and the role of publicly-funded dental care are an interesting area for debate. Perhaps NHS provision of tooth whitening or other cosmetic treatments could be justified if a patient’s dental appearance was found to negatively affect their social, or even economic, wellbeing? Further investigations of the interactions between social and economic disadvantage, visibly poor oral health and subconscious bias and discrimination in a U.K. context are warranted. Qualitative studies would be informative, including those seeking the views of potential employers on the impact of poor dental appearance at interview.

Public health interventions are often justified in terms of the potential for cost-savings and ‘return on investment’. Whilst we did find evidence suggestive of a negative impact of poor dental appearance on employment prospects,27–39 we did not find any to suggest that including dental care within ‘return to work’ programmes could improve employment outcomes, or result in economic gains. The most compelling evidence to support a role for dental care in reducing the social and economic impact of unemployment would be a randomised controlled trial of an integrated pathway into NHS dental care as part of a package of ‘return to work’ support; with employment status as the outcome. However, it is important to remember that facilitated access to dental care for marginalised groups can also be justified in light of the legal duty of NHS Commissioners to “have regard to the need to reduce inequalities between patients with respect to their ability to access health services, and… the outcomes achieved for them”. 58

Conclusions

There is a relatively abundant and diverse array of research to support to the conceptualisation that poor dental appearance may have negative impacts on employment. The applicability of this evidence-base to the UK health-system context and the demonstration of real-life impact on employment is more tenuous. Similarly, we did not identify any evidence to suggest that improving dental appearance could improve rates of employment. Further research is needed before programmes to improve dental appearance

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could be justified on the basis of improving employment outcomes. However, this does not mean that this type of support could not be justified already in terms of reducing health and social inequalities and capacity to benefit from publicly funded healthcare.

Declarations

N/A

Acknowledgements

The authors gratefully acknowledge the input of Mrs Sandra White in identifying the research topic. This study was funded by Public Health England. The views expressed are those of the authors and not necessarily those of Public Health England or the National Health Service.

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