Three-dimensional Finite Element Analysis of Bone Fixation in Bilateral Sagittal Split Ramus Osteotomy Using...

Area of Science:

• Biomaterials Engineering
• Orthodontics
• Biomechanics

Background:

• Orthognathic surgery frequently utilizes locking mini-plates and screws for mandibular advancement.
• Understanding biomechanical stress on these implants is critical for surgical success and patient outcomes.

Purpose of the Study:

• To investigate factors influencing stress on locking mini-plate/screws during orthognathic surgery.
• To analyze the impact of patient-specific bone characteristics on implant stress using finite element analysis.

Main Methods:

• Patient-specific 3-dimensional finite element models were created from 10 patients undergoing mandibular advancement.
• Osteosynthesis was performed using 2.0-mm titanium locking mini-plate/screws.
• Models were subjected to standardized loading conditions to simulate surgical stress.

Main Results:

• Higher von Mises stress values were observed on the plates/screws when the bone contact area was narrower (p<0.01).
• Lower bone mineral density (BMD) was significantly correlated with increased plate/screw stress (p<0.05).
• These findings highlight the influence of bone morphology and density on implant biomechanics.

Conclusions:

• Bone contact area and bone mineral density are significant factors affecting stress on fixation plates/screws in orthognathic surgery.
• Incorporating these patient-specific factors into pre-surgical planning may optimize implant selection and placement.