Use of a free conchal cartilage graft for closure of a palatal fistula: an experimental study and clinical application.

In order to establish an operative procedure for the closure of palatal fistulas, the usefulness of free conchal cartilage grafts was confirmed through animal experiments, and a clinical application of this procedure was attempted. In the animal experiment, an oronasal penetrating fistula 10 mm in diameter was formed in the hard palate of 33 rabbits. One month later, the size of the palatal fistula decreased to 2 to 3 mm in diameter in all the rabbits. These rabbits were divided into two groups. Group 1 (n = 8) was used as a control group. In group 2 (n = 25), the palatal fistula was closed by an autograft of conchal cartilage, and the conchal cartilage graft site was observed for a period of 16 weeks. In 75 percent (6 of 8) of group 1, the palatal fistula persisted even after 1 year, but in 96 percent (24 of 25) of group 2, the palatal fistula was closed. The palatal fistula closure procedure using a conchal cartilage graft was found to be remarkably effective (chi 2c = 10.9, p < 0.001). In the clinical application, a fistula closure procedure with the use of conchal cartilage grafts was attempted in 24 patients with palatal fistulas. The procedure was modified into three types according to the size of the palatal fistula. For type I (diameter less than 2 mm) a conchal cartilage graft was created as in the animal experiment. For type II (2 to 5 mm in diameter), a palatal fistula closure procedure was used employing both a small hinge flap and a conchal cartilage graft.(ABSTRACT TRUNCATED AT 250 WORDS)