Subject(s)
Natal Teeth/embryology , Natal Teeth , Australia , Academies and Institutes , Dental Research , HospitalsABSTRACT
La erupción temprana de dientes al nacimiento o en los primeros meses de vida son informados en la literatura en forma periódica. La clasificación más usada es la descripta por Massler y Savara (1950), que los calsifica en natales y neonatales. Se pueden asociar a ulceraciones traumáticas sublinguales (enfermedad de Riga-Fede). El objetivo de este trabajo es resumir las características más importantes en cuanto a diagnóstico, pronóstico y tratamiento de dientes natales y neonatales. Este trabajo informa un caso de una niña con dos dientes neonatales asociados a enfermedad de Riga-Fede, donde el tratamiento instaurado fue la extracción (AU)
Subject(s)
Humans , Infant, Newborn , Infant , Natal Teeth , Tooth Eruption/physiology , Tooth, Deciduous/abnormalities , Incisor , Natal Teeth/embryology , Natal Teeth/surgery , Natal Teeth/diagnostic imaging , Tooth Extraction/methods , Tooth/surgery , Oral Ulcer/complications , Prognosis , Argentina/epidemiologyABSTRACT
Teeth have been missing from birds (Aves) for at least 60 million years. However, in the chick oral cavity a rudiment forms that resembles the lamina stage of the mammalian molar tooth germ. We have addressed the molecular basis for this secondary loss of tooth formation in Aves by analyzing in chick embryos the status of molecular pathways known to regulate mouse tooth development. Similar to the mouse dental lamina, expression of Fgf8, Pitx2, Barx1, and Pax9 defines a potential chick odontogenic region. However, the expression of three molecules involved in tooth initiation, Bmp4, Msx1, and Msx2, are absent from the presumptive chick dental lamina. In chick mandibles, exogenous bone morphogenetic protein (BMP) induces Msx expression and together with fibroblast growth factor promotes the development of Sonic hedgehog expressing epithelial structures. Distinct epithelial appendages also were induced when chick mandibular epithelium was recombined with a tissue source of BMPs and fibroblast growth factors, chick skin mesenchyme. These results show that, although latent, the early signaling pathways involved in odontogenesis remain inducible in Aves and suggest that loss of odontogenic Bmp4 expression may be responsible for the early arrest of tooth development in living birds.
Subject(s)
Nuclear Proteins , Odontogenesis/physiology , Signal Transduction/physiology , Animals , Bone Morphogenetic Protein 4 , Bone Morphogenetic Proteins/genetics , Chick Embryo , Chickens , DNA-Binding Proteins/genetics , Fibroblast Growth Factor 8 , Fibroblast Growth Factors/genetics , Homeodomain Proteins/genetics , MSX1 Transcription Factor , Mandible/embryology , Mice , Mice, Mutant Strains , Morphogenesis , Natal Teeth/embryology , PAX9 Transcription Factor , Paired Box Transcription Factors , Transcription Factors/genetics , Homeobox Protein PITX2ABSTRACT
We describe a 24-weeks-old fetus with Fryns' syndrome (FS) and two erupted incisors. The present observations is another example of prenatal diagnosis of FS, based on ultrasonographically detected hernia diaphragmatica and cystic hygroma. It also adds an hitherto non described finding in FS. The presence of prenatally erupted teeth without any similar family history is discussed.
