Role of periosteum during healing of alveolar critical size bone defects in the mandible: a pilot study

ObjectivesMinipigs present advantages for studying oral bone regeneration; however, standardized critical size defects (CSD) for alveolar bone have not been validated yet. The objectives of this study are to develop a CSD in the mandibular alveolar bone in Aachen minipigs and to further investigate the specific role of periosteum.Materials and methodsThree female Aachen minipigs aged 17, 24, and 84 months were used. For each minipig, a split-mouth design was performed: an osteotomy (2 cm height x 2.5 cm length) was performed; the periosteum was preserved on the left side and removed on the right side. Macroscopic, cone beam computed tomography (CBCT), microcomputed tomography (mu CT), and histological analyses were performed to evaluate the bone defects and bone healing.ResultsIn both groups, spontaneous healing was insufficient to restore initial bone volume. The macroscopic pictures and the CBCT results showed a larger bone defect without periosteum. mu CT results revealed that BMD, BV/TV, and Tb.Th were significantly lower without periosteum. The histological analyses showed (i) an increased osteoid apposition in the crestal area when periosteum was removed and (ii) an ossification process in the mandibular canal area in response to the surgical that seemed to increase when periosteum was removed.ConclusionsA robust model of CSD model was developed in the alveolar bone of minipigs that mimics human mandibular bone defects. This model allows to further investigate the bone healing process and potential factors impacting healing such as periosteum.

Automated summary

A standardized critical size defect (CSD) model was developed in the mandibular alveolar bone of minipigs to investigate the role of periosteum in bone healing process. It was found that the removal of periosteum resulted in a significant decrease in bone volume and density, indicating the important role of periosteum in bone regeneration.