Improvement of the maxillary bone growth suppression in the cleft palate operation with cultured dermal substitute: animal experiment and patient reports in preliminary clinical application

Cleft palate patients often show impaired maxillary bone growth after cleft-palate-correction surgery. We attempted to investigate and elucidate the effects of using allogeneic, cultured dermal substitute (CDS) to cover an exposed, palatal bone surface in animal experiments. Fibroblasts from the abdominal skin of Wistar rats were cultured. Subsequently, the fibroblasts were seeded onto a matrix that composed of hyaluronic acid and atelo-collagen. Forty Wistar rats (3-week-old males) were assigned to one of four groups: control, open-treatment, matrix and CDS groups. The control group (n=5) received no surgical operations. In the open-treatment group (n=11), the mucosa and periosteum of the left-half of the palate were removed surgically and the bone was exposed. In the matrix group (n=11), the area of exposed bone was covered with only the matrix, excluding any cells. In the CDS group (n=10), the area of exposed bone was covered with CDS.

At 9 weeks postoperatively, biopsies of the wounds were obtained. Skull preparations were made and the palatal widths were determined. The palatal widths in the CDS group were significantly wider compared to the matrix and open-treatment groups (P<0.05). However, there were no significant differences when the CDS group was compared to the control group. Haematoxylin, eosin and CD31 immunostaining confirmed a larger number of capillaries in the CDS group. This animal experiment suggested that this procedure might provide an optimum wound-healing condition, thus, reducing the maxillary bone-growth suppression. Therefore, a preliminary clinical application in three patients was performed using the autologous CDS after the pushback method.