The key finding
A 2025 international Delphi study brought together 74 maxillofacial surgeons from around the world to identify what we don’t know about orthognathic surgery—procedures that correct misaligned jaws. After two rounds of structured surveys, these experts reached consensus on 15 clinically relevant research questions that currently lack adequate evidence. The study achieved a 74% retention rate between rounds (55 surgeons completed both), and participants demonstrated ‘almost perfect’ agreement in their assessments, suggesting these gaps reflect genuine concerns shared across the surgical community rather than isolated opinions.
What the study looked like
Researchers used the Delphi technique, a structured method for building expert consensus, to evaluate evidence gaps previously identified in a comprehensive mapping review of orthognathic surgery literature. They recruited surgeons who regularly perform jaw realignment procedures through multiple channels: authors of studies in the mapping review, recommendations from peers, and social media outreach. Participants completed two rounds of surveys containing Likert-type rating scales (where respondents indicate their level of agreement) and open-ended questions about the clinical importance of various evidence gaps. After the first round, researchers refined the questions based on feedback, then circulated a second survey. Consensus was defined as 60% agreement among participants. Seventy-four surgeons participated initially, with 55 completing both rounds. Statistical analysis measured how closely participants agreed with each other across both survey rounds.
Why researchers think this happened
The study authors note that orthognathic surgery, while widely performed, has evolved largely through clinical experience and tradition rather than systematic research answering fundamental questions. The mapping review that preceded this Delphi study apparently revealed numerous areas where high-quality evidence is scarce or absent. By consulting practicing surgeons rather than relying solely on academic assessments, the researchers aimed to distinguish between theoretical knowledge gaps and those that actually affect patient care decisions. The fact that surgeons themselves proposed 11 additional evidence gaps during the first round suggests that frontline clinical experience reveals uncertainties not always captured in published literature. The high level of agreement among international participants indicates these aren’t regional practice variations but rather universal questions the field faces.
How to read this carefully
This study identifies what we don’t know—it doesn’t provide answers to the 15 research questions identified. The specific evidence gaps aren’t detailed in the abstract, so readers cannot assess whether they concern surgical techniques, patient selection, timing of intervention, or outcomes measurement. While 74 surgeons represents reasonable participation for a Delphi study, this remains a relatively small fraction of maxillofacial surgeons worldwide, and the recruitment methods (published authors, peer networks, social media) may have introduced selection bias toward academically engaged surgeons. The 60% consensus threshold is somewhat arbitrary; different thresholds would yield different lists. Additionally, agreement among experts about what’s unknown doesn’t necessarily indicate what research should be prioritized—some gaps may be more feasible or impactful to address than others.
What this means for everyday life
If you or someone you know is considering orthognathic surgery for jaw alignment issues, this study suggests that some treatment decisions may be based more on surgical experience than rigorous research evidence. This doesn’t mean the procedures are unsafe or ineffective—many medical interventions work well despite evidence gaps—but it does suggest that asking your surgeon about the evidence supporting specific approaches is reasonable. When surgical experts themselves identify 15 major unanswered questions in their field, it highlights the importance of asking questions during consultations: Why is this approach recommended? What alternatives exist? What do we know and not know about outcomes? This study’s roadmap for future research may eventually lead to more evidence-based protocols, potentially improving patient selection, surgical planning, and post-operative care in the years ahead.