Related Experiment Video
Updated: Apr 14, 2026

A Protocol for Roux-en-Y Gastric Bypass in Rats using Linear Staplers
Published on: August 21, 2021
Weight loss in orthognathic surgery: a clinical study
Objective:
To analyse weight change, body composition change and Body Mass Index change in patients undergoing orthognathic surgery.
Design:
A service evaluation was undertaken in orthognathic patients pre-operatively and at 4 weeks post-surgery.
Setting:
Queen Elizabeth Hospital Birmingham outpatient department.
Subjects:
Thirty-one patients scheduled for single- or two-jaw orthognathic surgery and rigid internal fixation.
Methods:
Immediately pre-operatively and at 4 weeks post-surgery the following information was gathered: (1) patient height; (2) patient weight (kg); (3) Patient Body Mass Index; and (4) patient body fat percentage.
Results:
In the 4-week post-operative period, the average weight loss was -4·96 kg (range: -9·6 to +3·0 kg), with a body fat reduction of -3·07% (range: -5·80% to +2·30%) and an average reduction in Body Mass Index of -1·63 (range: -3·4 to +0·8). There was no statistically significant difference in weight loss (P = 0·1562) or body fat composition change (P = 0·2391) between single- or two-jaw surgery. There was no statistically significant difference in weight loss (P = 0·4858) or body fat composition change (P = 0·5321) between male and female patients.
Conclusions:
Weight loss observed was similar to that reported in studies using inter-maxillary fixation. Closer psychological and dietetic support is needed for patients who have a low normal or underweight Body Mass Index. Better and more bespoke tailored Oral Nutritional Supplementation must be provided for all orthognathic surgery patients to potentially reduce this significant weight loss.
More Related Videos
06:26Quantitative Assessment Protocol for Facial Soft Tissue Volumetric Changes with Stereophotogrammetry
Published on: December 9, 2025
05:54Real-Time Dynamic Navigation System for the Precise Quad-Zygomatic Implant Placement in a Patient with a Severely Atrophic Maxilla
Published on: October 18, 2021