Mandibular osteotomy fixed with biodegradable plates and screws: an animal study

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Veterinary Medicine

Background:

• Mandibular osteotomies require stable fixation for effective healing.
• Biodegradable fixation devices offer potential advantages over traditional metallic implants.
• Self-reinforced poly-L-lactide (SR-PLLA) is a promising biodegradable polymer for orthopedic applications.

Purpose of the Study:

• To evaluate the efficacy and biocompatibility of SR-PLLA multi-layer plates and screws for mandibular osteotomy fixation in a sheep model.
• To assess the healing process and implant integrity over time.
• To determine the suitability of SR-PLLA devices for clinical application in human mandibular reconstructions.

Main Methods:

• Unilateral mandibular body osteotomies were performed in nine sheep.
• Fixation was achieved using SR-PLLA multi-layer plates and screws.
• Radiological, mechanical, and histological assessments were conducted at 6, 12, and 24 weeks post-surgery.
• Analysis of the explanted biodegradable material was performed.

Main Results:

• SR-PLLA plates and screws provided sufficient mechanical stability for osteotomy fixation.
• Radiological and histological findings indicated successful osteotomy healing, primarily through callus formation.
• The biodegradable implants maintained their structural integrity throughout the study period.
• No need for maxillomandibular fixation was observed, simplifying the surgical procedure.

Conclusions:

• SR-PLLA multi-layer plates and screws are a viable and successful option for fixing mandibular osteotomies in sheep.
• The use of these biodegradable devices promotes natural bone healing without compromising stability.
• Further research and potential miniaturization of the implants are recommended before human clinical trials.