Dermal Matrix Graft Effects on Facial Growth in a Veau-Wardill-Kilner Palatoplasty Model: An Experimental Study in Rats.

The primary goal of palatoplasty is the restoration of normal speech, that can be aimed by, among many procedures, lengthening the palate through the pushback technique; one of its complications is abnormal maxillary growth. The main factor affecting facial growth in CLP patients is believed by many to be the palatoplasty-due to the large scar retraction resulting from some surgical techniques. The non-crosslinked two-layer bioabsorbable collagen matrix Mucograft (Geistlich Pharma AG, Wolhusen, Switzerland) is a potential tool to aid in wound closure in a second-intention healing situation. The objective of this work was to test the use of an acellular dermal matrix (Mucograft) in an experimental model of Veau-Wardill-Kilner palatoplasty, as a tool to reduce scar retraction of the denuded palatine mucosa. Twenty-four 3-week-old male Wistar rats were used. The animals were randomly divided into two groups. In the control group, an excision was made with bone exposure in the palate, simulating the defect left in the Veau-Wardill-Kilner palatoplasty. In the intervention group, the same procedure was performed, and the area of denuded palatine bone was treated with a bioabsorbable collagen matrix (Mucograft). For data collection, 9 weeks after surgery (12 weeks of life), the animals were euthanized by excessive anesthetic dosage. Maxillary growth, macroscopic appearance of the scar, pain, and bleeding were evaluated. There were significant statistical differences between the groups for palate length growth (7.6 mm + -0.38 mm vs 5.5 mm + -0.36 mm,  = .009) and for palate width growth (1.47 mm + -0.8 mm vs -0.09 mm + -0.55 mm,  = .001), favoring dermal matrix group compared to controls. Whereas for pain and bleeding, there were no differences between the groups. The use of dermal matrix in rats with an area of bone denudation on the palate increases maxillary length and width growth patterns. Besides, it does not increase pain, bleeding, or post-operative complications.