Letter to Aesthetic and Psychosocial Impacts of Hyaluronic Acid Fillers in Patients with Retrognathic Profiles.

This Letter to the Editor provides a comment of de Almeida Silva L et al. "Aesthetic and Psychosocial Impacts of Hyaluronic Acid Fillers in Patients with Retrognathic Profiles." While the original study contributes to understanding the psychosocial effects of non-surgical enhancement techniques, several concerns warrant consideration. First, the absence of a control or comparator group undermines causal inference, as improvements in aesthetic satisfaction and self-esteem could stem from placebo effects or observer bias rather than the biological action of hyaluronic acid. The implementation of a randomized or sham-controlled design would strengthen the internal validity of similar future research. Second, the statistical approach relied heavily on p values without reference to minimal clinically important differences or correction for multiple testing, raising uncertainty about the clinical relevance of the reported improvements. Third, the narrow participant inclusion-limited to young female patients with mild retrognathia-restricts generalizability, potentially introducing self-selection bias in a population already motivated toward aesthetic enhancement. Lastly, the article could have provided a more nuanced discussion of ethical considerations, especially regarding informed consent, patient expectations, and the cumulative risks of repeated filler injections that only mask, rather than correct, underlying skeletal discrepancies.Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .