A standardized rat burr hole defect model to study maxillofacial bone regeneration

Area of Science:

• Biomaterials Science
• Surgical Innovation
• Regenerative Medicine

Background:

• Maxillofacial burr hole bone defects have a high incidence rate and unique regenerative properties, necessitating specialized animal models for evaluating bone regenerative approaches.
• Existing bone defect models in long or calvarial bones do not fully capture the distinct developmental origins and regenerative environments of the mandible.
• There is a need for well-standardized small animal models to assess the efficacy of novel biomaterials for maxillofacial bone regeneration.

Purpose of the Study:

• To develop and standardize a rat mandible burr hole bone defect model suitable for evaluating bone regenerative strategies.
• To ensure minimal tissue damage and optimize animal welfare during model creation.
• To provide a reliable platform for preliminary screening of regenerative approaches before large animal and clinical trials.

Main Methods:

• Anatomical dissection of rat mandibles to identify optimal defect locations, specifically the anterior tooth area, avoiding critical organs.
• Standardization of the model by controlling animal age, weight, and gender, using standardized instruments, and minimizing operator variability.
• Determination of appropriate defect sizes (6 × 2 mm and 8 × 2 mm) to prevent self-rehabilitation and ensure suitability for regenerative studies.

Main Results:

• A standardized rat mandible burr hole bone defect model was successfully established with minimal surgical trauma.
• The anterior tooth area was identified as ideal for defect creation due to sufficient bone volume and avoidance of vital structures.
• Defect sizes of 6 × 2 mm and 8 × 2 mm were validated as effective for bone regenerative research.

Conclusions:

• The developed rat mandible burr hole model offers a standardized, reproducible, and minimally invasive method for evaluating maxillofacial bone regenerative approaches.
• This model provides crucial in vitro outcome validation and preliminary screening data for future preclinical and clinical investigations.
• Implementation of this model can significantly optimize the evaluation system for bone regenerative therapies targeting maxillofacial defects.