GP4b - What Are Orthognathic Surgery Patients Discussing Online? A Computational Analysis With Large Language Model

Abstract: Introduction: Patients increasingly use social media to seek information about orthognathic surgery, yet the specific topics prioritized in large-scale, patient-driven discussions remain poorly characterized. Prior studies have mainly focused on content accuracy or small manually coded samples, limiting insight into patient-centered informational needs. This study aimed to characterize patient discussion of orthognathic surgery on Reddit using a neural topic modeling and large language model (LLM) computational pipeline and to identify themes extending beyond traditional preoperative counseling.

Materials and Methods: This retrospective, cross-sectional computational study analyzed publicly available comments from the r/jawsurgery subreddit posted between October 2017 and December 2024. All English-language comments were included. Comments consisting solely of hyperlinks, deleted or removed content, and non-English text were excluded. Data were obtained from the Pushshift Reddit dataset using programmatic extraction.

A two-stage analytic pipeline was implemented. First, unsupervised topic modeling was performed using BERTopic. Comment text was converted into vector embeddings, followed by dimensionality reduction with Uniform Manifold Approximation and Projection (UMAP) and clustering with Hierarchical Density-Based Spatial Clustering of Applications with Noise (HDBSCAN). Second, topic clusters were consolidated into clinically interpretable meta-topics using an LLM with structured prompting.

Descriptive statistical methods were used to summarize topic prevalence and temporal trends. Topic prevalence was defined as the proportion of comments assigned to each topic. Annual comment volume and longitudinal trends were also analyzed.

Results: Of 454,867 comments, 373,718 (82.2%) were classified into 396 topic clusters, and 81,149 (17.8%) were categorized as noise. Among classified comments, preoperative planning and consultations accounted for 146,541 of 373,718 comments (39.2%), and postoperative recovery and self-care accounted for 120,733 (32.3%). Together, these two meta-topics represented 71.5% of classified comments.

At the individual topic level, pre-surgery research was the most prevalent theme, comprising 121,478 of 373,718 comments (32.5%). This was followed by surgery experiences and recovery, which accounted for 96,802 comments (26.0%), and sleep apnea surgery, which accounted for 32,070 comments (8.58%). Complications, risks, and medicolegal concerns represented 20,496 comments (5.48%). Additional lower-frequency themes included surgical esthetics, orthodontic care, temporomandibular joint-related symptoms, and psychosocial considerations.

Discussion volume increased substantially over the study period. Comment activity rose from 4 comments in 2017 to 174,594 comments in 2024, representing 38.4% of the total dataset. Year-over-year growth was sustained throughout the study period. Mean comment length declined over time.

Conclusion: Patient-generated discussions of orthognathic surgery on Reddit were centered on preoperative planning, postoperative recovery, and other practical aspects of care rather than operative technique alone. Patients frequently engaged in independent research, peer-shared experiences, and discussions of risks and logistics, suggesting a gap between patient informational needs and traditional surgeon-directed counseling. Incorporating structured decision-making guidance, staged recovery expectations, and proactive discussion of commonly explored topics may improve patient-centered communication and perioperative preparedness.