Maxillary Growth following Atelocollagen Implantation on Mucoperiosteal Denudation of the Palatal Process in Young Rabbits: Implications for Clinical Cleft Palate Repair

Objective: The implantation of atelocollagen matrix on the denuded surface of palatal bone following cleft palate repair has been used because it enhances wound healing. This study was performed to determine whether the beneficial effect of atelocollagen matrix implantation on the prevention of scar tissue contraction also inhibits the scar's interference with the growth of maxillary bone. Method: Fifty New Zealand White rabbits (aged 4 weeks) underwent palatal mucoperiosteal denudation, and atelocollagen matrix was implanted on the left palatal process. The opposite side was left open as a control. Results: Histopathologically, the implantation side exhibited early infiltration of mononuclear cells and fibroblasts, and better growth of connective tissue strands and epithelium. in addition, the formation of rete ridges were seen that were similar to the normal mucosa. The bone of the atelocollagen-implanted side was covered with regenerated periosteum-like layers, but that of the control side was lined by granulation tissue, suggesting the existence of continuous inflammation on the periosteal region. When the animals reached adulthood (aged 24 weeks), the areas of scars and palatal processes, palatal shelf width, molar teeth incline, and bone mineral contents were measured and compared between sides. The atelocollagen-applied scars showed less contraction, the area and width of atelocollagen-implanted palatal processes showed more satisfactory growth, and the dental arch deformity was suppressed in comparison with the control side. Conclusions: Our results suggest that the use of atelocollagen matrix on the denuded bone surface following cleft palate repair decreases the scar's effect on maxillary growth.