Nutrition after orthognathic surgery: Evaluation of anthropometric measurements and body composition in subjects undergoing orthognathic surgery with nutritional management

Abstract

Orthognathic surgery represents a fundamental therapeutic approach for correcting severe skeletal jaw deformities that cannot be resolved through orthodontic treatment alone. Beyond restoring occlusal function, it also enhances speech, mastication, breathing, and facial aesthetics. The procedure generally involves repositioning the maxilla, mandible, or both, requiring close collaboration between orthodontists and maxillofacial surgeons to ensure optimal outcomes. However, the postoperative phase presents significant challenges, particularly related to nutrition and metabolic stress. Surgical trauma induces a catabolic state that accelerates protein breakdown and lean mass loss, with the most pronounced weight reduction occurring within the first two postoperative weeks. Patients often experience restricted mandibular mobility for 3–4 weeks, necessitating a transition to liquid or semi-liquid diets. This limitation, combined with increased energy and protein requirements—estimated at 2500–3000 kcal and 1–1.5 g/kg protein per day—places individuals at high risk of inadequate intake. Poor nutritional support may impair wound healing, prolong recovery, and negatively affect body composition and biochemical parameters. Clinical studies consistently document significant postoperative weight loss, averaging between −2.5 and −5 kg, with marked reductions in fat mass during the initial month after surgery. Given these findings, nutritional management emerges as a critical determinant of surgical success. Evidence suggests that supplementation with compact, high-calorie, high-protein oral nutritional supplements (ONS) or nutrient-dense natural shakes, in combination with structured dietary counselling, can mitigate postoperative weight loss and preserve lean body mass. This study therefore aims to evaluate the efficacy of targeted nutritional interventions—providing an average of 325 kcal and 20 g protein per serving—in improving anthropometric and body composition outcomes compared with standard care. By addressing the interplay between surgical stress, dietary limitations, and metabolic demands, the research highlights the importance of personalized perioperative nutrition as an integral component of orthognathic surgery management.