The enamel of a natal tooth in a healthy full-term child and the enamel of a postnatally erupted tooth in a premature child have been studied with scanning electron microscopy on longitudinal and cross sections. The first case shows that following a normal development, amelogenesis was arrested. This is evident by the presence of the external aprismatic layer in spite of the narrowness of the enamel which corresponds to about a third of the normal thickness. This premature arrest of amelogenesis can be dated to about the 6th month "in utero". In the second case we observed a reversible amelogenesis disturbance as attested by the absence of the external aprismatic layer as well as by a new and fast enamel apposition that took a pseudonormal course. Happening about 10 weeks before birth, this disturbance has probably been induced by factors of maternal origin. In both cases, the eruption anomaly was associated with an enamel anomaly. These observations open new perspectives in the study of natal and neonatal teeth. By extension, such observations are likely to produce complementary informations in neonatology.
Download full-text PDF |
Source |
---|
J Biophotonics
April 2013
Université Montpellier 2, Laboratoire Charles Coulomb UMR 5221, F-34095 Montpellier, France.
Multiphoton microscopy has been used to reveal structural details of dentine and enamel at the dentin-enamel junction (DEJ) based on their 2-photon excited fluorescence (2PEF) emission and second harmonic generation (SHG). In dentine tubule 2PEF intensity varies due to protein content variation. Intertubular dentin produces both SHG and 2PEF signals.
View Article and Find Full Text PDFMinerva Stomatol
April 2006
Department of Dentistry and Stomatology, University of Florence, Florence, Italy.
Aim: Recently, there has been a tendency to simplify bonding procedures. Current self-etching adhesives combine conditioning, priming and bonding functions thus reducing technique-sensitivity as well as the risk of making errors. Another important advantage of this approach is that it allows the resin to etch and infiltrate the substratum simultaneously thus reducing the risk of any discrepancy between these 2 processes.
View Article and Find Full Text PDFAnat Rec
May 2000
Zoological Institute, University of Cologne, 50923 Köln, Germany.
The pathological alterations of enamel structure in the teeth of wild boars from fluoride polluted areas in N-Bohemia (Czech Republic) and S-Saxony (Germany) were studied on a macroscopic and a microscopic level. Mandibular bone fluoride concentration (mg F(-)/kg, dry wt; mean +/-SD, individuals <24 months of age) in the specimens from N-Bohemia (754.3+/-149.
View Article and Find Full Text PDFSchweiz Monatsschr Zahnmed
March 1994
Service de Pédodontie, Faculté de Chirurgie Dentaire, Université Louis Pasteur, Strasbourg.
The enamel of a natal tooth in a healthy full-term child and the enamel of a postnatally erupted tooth in a premature child have been studied with scanning electron microscopy on longitudinal and cross sections. The first case shows that following a normal development, amelogenesis was arrested. This is evident by the presence of the external aprismatic layer in spite of the narrowness of the enamel which corresponds to about a third of the normal thickness.
View Article and Find Full Text PDFThe authors verify the presence of an aprismatic layer at the surface of human deciduous and permanent, erupted and non erupted teeth, by means of the polarizing and scanning electron microscope. The results allowed the Authors to conclude that the presence of different extents of aprismatic enamel at the surface of human teeth should be regarded as a constant and normal feature, with some different frequency and organization patterns between different tooth types.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!