Single layered periosteoplasty in experimental mid-palatal clefts. A histological study in the cat.

At the age of 2 months, the mid-palatal suture, with adjacent bone and nasal mucoperiosteum, was resected in 20 domestic cats leaving postoperatively only the oral side of the more than 5 mm wide osseous defect covered with mucoperiosteum. After cessation of general growth this single layered "palatal cleft periosteoplasty" had, an all animals, resulted in the formation of new bone extending from the resection edges, i.e. nearly butting in the midline in about 85% of the cases. Bone bridges interlocking the palatal halves were, as in normal untreated individuals, never observed. In 3 out of 20 other cats where merely an oral mucoperiosteal flap had been elevated and replaced, i.e. a shamoperation without resection of bone or mucoperiosteum, a beginning synostosis of the mid-palatal suture was found. In the remaining 17 cats of this last group and in further 20 unoperated controls, the suture was open even at 2 1/2 years of age. The results seem to indicate that soft tissue trauma inevitable in palatal surgery may interfere with periosteal and sutural integrity. In addition, the findings may render new informations in palatal/maxillary growth following cleft palate periosteoplasty.