Human and Animal Studies in Craniofacial Embryology Enrich Human Postnatal Craniofacial Insight Differently

Objectives: To compare results obtained since 1970 from craniofacial embryological studies on human fetal tissues with results from similar studies performed on animal tissues and focus on how the different tissue types and methods can enrich the human postnatal craniofacial research. There are three sections: i) research on normal and pathological human fetal material, ii) animal experimental research performed on different species, and iii) comparisons of the results obtained. Human Material: On human prenatal material, normal and pathological developmental processes in the mandible, maxilla, nasal cavity, body axis, cranial base, vomeronasal organs, pituitary gland and nervous system were related to postnatal findings. Specific focus was given to pre/postnatal bridging of observations on holoprosencephaly, cleft lip/palate, Down syndrome, myelomeningocele/spina bifida, Kallmann syndrome, Turner syndrome and Fragile X syndrome. Demarcations of pathological regions in Cri du chat, Velo-cardio-Facial syndrome and Crouzon syndrome were mapped. Animal Material: Animal experimental results from studies on the notochord, gastrulation, neural crest, hindbrain, rhombomere, homeobox genes and experimentally induced malformation were presented. Comparing materials: The educational background of the scientists performing human and animal research, their postnatal clinical experience, the research materials used and the methods available for research are compared. Furthermore, the obtained findings result in a “pro et contra list” indicating what is positive and what is negative for improving postnatal human diagnostics. Conclusion: Human and animal studies in craniofacial embryology enrich human postnatal craniofacial insight differently. Future cooperation between human and animal research cultures is recommended.