Wound healing of the palatal mucoperiosteum in beagle dogs after surgery at different ages.

The aim of this study was to investigate macroscopic wound healing after palatal surgery at three different ages. A total of 37 beagle dogs was used, divided into three experimental groups, a control group and a sham-operated group. Palatal surgery was performed at the age of 6, 16 or 25 weeks respectively. The animals of the sham group and the control group were studied from the age of 6 weeks on. All animals were studied longitudinally over a period of six weeks. The three experimental groups were compared mutually and the youngest experimental group was compared with the sham group and the control group. Clinically the wound healing in the median region was complete after two weeks in all animals. In the denuded areas the wound healing continued for the youngest experimental group for 2 to 3 weeks postoperatively and for the two older age groups for 4 to 5 weeks postoperatively. The wound contraction in the denuded areas, recorded as the increasing approximation of the opposite tattoo points was larger in the two older age groups than in the youngest one and was restricted mainly to the first postoperative week. This effect seemed to be permanent because no compensating increase in distance was found later on. It was concluded that shortly after operation wound contraction was mainly responsible for the reduction of the surface area of the denuded bone, but later on, epithelial cell proliferation was the predominant factor.