Normal palatal sutures in newborns and fetuses: a critical fact for successful palatal distraction.

Distraction osteogenesis (DO) has recently been applied to the palate. Successful posterior lengthening and medial advancement of the palates was continuously reported. Based on these studies, it is obvious that DO will play a major role in the management of problems related to palatal defects in the near future. Although the results are appealing, they may not be applicable for humans due to anatomic differences. All experimental studies used normal palatal sutures of young dogs for size expansion. Therefore, it is necessary to know normal palatal sutures in infants before one can clinically apply this new technique. With consent, palates of fetuses and neonates who died of various causes were examined. Eight fresh cadavers were available for the dissection, with two being skeletonized using the boiling process. There were three fetal deaths in utero (33-41 weeks of gestational age) and five postnatal deaths (aged between 5 hours and 6 months). All specimens were grossly normal in shape and size except for one with a unilateral complete cleft of lip and palate. A midline palatal suture was found in every noncleft specimen, while premaxillary and transverse palatomaxillary sutures were present in every specimen. Laterally, there was no true suture except for the most posterior portion, which was contiguous with the greater palatine foramen. The palatal sutures of third-trimester fetuses and neonates are not different from adult ones. There is no lateral suture that will allow distraction in the medial direction. It is only the posterior hard palate (palatine bones) that can potentially be moved medially and posteriorly by sutural expansion with DO.