When we teach evidence-based dentistry (EBD), we emphasise the importance of formulating clear, answerable questions. Over time, however, a pattern emerges. We have become highly skilled at asking certain kinds of research questions, and far less skilled at asking others.

Systematic reviews continue to accumulate around familiar clinical and preventive interventions. This is a strength of the discipline. Yet some of the most persistent oral health challenges, particularly those linked to diet and everyday behaviour, remain stubbornly resistant to change despite decades of high-quality evidence. This raises a possibility worth exploring: when evidence remains consistent but outcomes remain difficult to shift, the limitation may lie not only in available data, but in the scope of the questions we ask and the range of stakeholders involved in shaping them.

When knowledge does not translate into change

The relationship between diet and oral health is well established. From early work on sugar and caries to contemporary understanding of free sugars, frequency and erosion, the biological pathways are clear. Dietary advice therefore forms a routine component of preventive care1,2,3,4.

Yet diet-related oral diseases remain among the most prevalent chronic conditions globally. Many patients are well aware of the key messages. The difficulty is not a lack of knowledge but the challenge of implementing that knowledge within contemporary food environments characterised by convenience, affordability pressures and the normalisation of frequent sugar exposure. In this context, prevention depends heavily on sustained individual vigilance. Evidence from behavioural science suggests that information alone rarely produces durable population-level change when surrounding environments remain unchanged1,5.

Dentistry has traditionally focused on generating evidence and advising patients at the individual level. It has been less engaged with the broader systems in which dietary choices are made.

The questions we ask and those we do not

EBD has rightly emphasised reducing research waste and aligning research with real-world priorities6. However, there is a subtler risk: repeatedly asking narrow questions within established paradigms while overlooking broader uncertainties that sit outside traditional clinical frameworks.

If we continue to ask only whether a specific dietary intervention reduces caries incidence, we will continue to produce systematic reviews addressing that question. What we may not generate is evidence on how dietary advice interacts with food environments, commercial practices or social norms.

Creative or unconventional questions can feel uncomfortable because they sit at disciplinary boundaries. Yet it is often at the intersection of environments, systems and behaviours — rather than within isolated interventions that the greatest potential for unexpected change lies.

A thought experiment: the dental-friendly menu

Consider a simple thought experiment. Imagine entering a café or restaurant where certain options are identified as “tooth-considerate”, not prescriptively, but as an additional form of information. Water and milk-based drinks are prominent. Lower free-sugar options are easy to identify. Desserts are positioned primarily as part of meals rather than as frequent stand-alone snacks.

Would such cues influence purchasing behaviour? Would they reduce frequency of sugar exposure? Would they be commercially viable? Would they be perceived as supportive or intrusive? Dentistry currently has limited evidence to answer these questions, not because they lack relevance, but because they have rarely been framed as researchable within our field.

The “dental-friendly menu” is therefore less a proposal than a prompt. It invites us to consider what kinds of evidence might be generated if we began to examine oral health within everyday food environments rather than only within clinical or educational interventions.

Expanding stakeholder engagement

Pursuing such questions would require broader stakeholder engagement than dentistry has traditionally undertaken. Evidence-based healthcare has increasingly recognised the value of involving patients and the public in research prioritisation. A similar expansion may be needed in relation to commercial and community environments.

If we explore this within the context of our thought experiment and accept that dietary behaviours are shaped within food systems, then those working within these systems become relevant stakeholders in preventive research. This includes not only nutrition and public-health professionals, but also individuals across the restaurant and hospitality sector. Engaging with such stakeholders is not straightforward. It requires moving beyond the assumption that relevant expertise sits solely within health professions. It also requires recognising that stakeholder engagement must be diversified, not only in terms of including more voices, but in understanding the heterogeneity within sectors themselves.

The diversity within the restaurant sector

The “restaurant sector” is often spoken of as if it were a single entity. In reality, it encompasses a wide range of settings: multinational chains, small independent cafés, family-run restaurants, school and workplace canteens, street-food vendors and fine-dining establishments. Each operates under different economic pressures, regulatory constraints and customer expectations.

For a multinational chain, menu changes may involve complex supply chains, branding considerations and shareholder expectations. For a small independent café, even minor adjustments can carry significant financial risk. Street-food vendors may operate within entirely different regulatory and economic contexts. Institutional catering settings such as schools or hospitals have yet another set of constraints and opportunities. Consumer demographics also vary widely across these settings, shaping what is commercially viable and socially acceptable. Price sensitivity, cultural preferences and local competition all influence menu design and marketing strategies.

Any thought experiment about dental-friendly environments must therefore account for this diversity. A model that is feasible in one segment may be unrealistic in another. Research that treats the restaurant sector as homogeneous risks generating conclusions that are neither implementable nor equitable.

From imagination to researchable questions

Exploring these complexities does not require abandoning methodological rigour. On the contrary, it opens new avenues for empirical investigation. For example:

  • How do different types of food outlets perceive and respond to oral-health-related initiatives?

  • What operational constraints shape menu design across various segments of the sector?

  • Do visible “tooth-considerate” options influence consumer behaviour in different settings?

  • How might such initiatives interact with existing inequalities in food access and affordability?

  • What forms of collaboration between dentistry and hospitality are feasible and acceptable?

These questions lend themselves to mixed-methods research combining behavioural data, qualitative insight and economic evaluation. They also require interdisciplinary collaboration and co-design approaches that extend beyond traditional dental research partnerships.

Importantly, such work would generate new forms of evidence, not replace clinical trials or systematic reviews. It will complement them by addressing uncertainties that sit at the interface between clinical knowledge and everyday life.

Why this matters for the future of EBD

EBD has always been concerned with aligning research with real-world needs and reducing uncertainty in ways that matter for patients. To do so effectively, we must remain attentive not only to how we synthesise evidence, but also to how we generate questions and who participates in shaping them.

Diversifying stakeholder engagement is part of this process. So too is recognising that some of the most pressing preventive challenges lie outside the traditional boundaries of clinical research.

The dental-friendly menu may or may not prove feasible in practice. That is ultimately an empirical question. Its value here lies in what it reveals about our research habits. When we allow ourselves to explore unconventional questions and engage with a wider range of stakeholders, new forms of evidence become possible.

If EBD is to continue evolving, it must remain open to such exploration. Otherwise, we risk producing increasingly sophisticated answers to increasingly narrow questions, while the broader challenges of prevention remain unresolved.

The future of EBD may depend not only on the quality of our methods, but on the breadth of our curiosity and the diversity of the voices we invite into the research conversation.