Assessment of Orofacial Function After Mandibular Angle Harmonization with Hyaluronic Acid: A Longitudinal Observational Study.

Background: The relationship between facial aesthetic procedures and changes in the stomatognathic system has attracted increasing interest, motivating investigations into their functional and structural impacts. This longitudinal observational study analyzed molar bite force and orofacial tissue pressure in adults who underwent hyaluronic acid injections in the mandibular angle. Methods: Ten adults (eight women and two men; mean age 34.3 ± 11.2 years) with normal occlusion and no temporomandibular disorders were included. The MD Codes guided injection points of 2 mL of hyaluronic acid in the mandibular angle. Maximum right and left molar bite force was measured using a digital dynamometer, and tongue, lip, and cheek pressures were measured with a Pro-Fono Biofeedback device. Assessments occurred before and at 15, 30, and 60 days. Repeated measures ANOVA with Bonferroni correction was applied (p < 0.05), and effect sizes and 95% confidence intervals were calculated. Results: No statistically significant differences were observed in maximum molar bite force throughout the follow-up period. Regarding orofacial pressures, a significant main effect of time was observed for tongue pressure (p = 0.03); however, the effect size was moderate-to-large, and values showed considerable variability across participants. Lip and cheek pressures remained stable over time. Conclusions: Hyaluronic acid injection in the mandibular angle did not show clinically detectable changes in maximum molar bite force, suggesting short-term preservation of masticatory function within the 60-day follow-up period. These findings are limited to short-term observations and specific sample characteristics. The observed variation in tongue pressure may reflect adaptive functional adjustments, although variability across participants was considerable.