Scanning Electron Microscopy and Macroscopic Examination of Prematurely Erupted Teeth in Preterm Infants
Abstract
Prematurely erupted teeth are rare in full-term neonates and extremely rare in prematurely delivered infants. The aim of this study was to present macroscopic and scanning electron microscopy (SEM) investigations of prematurely erupted primary teeth of preterm very low birthweight (VLBW) and extremely low birthweight (ELBW) infants.
Three preterm VLBW and ELBW infants with prematurely erupted lower incisors were examined. The dental examination assessed the type, location, clinical appearance and degree of mobility of the prematurely erupted teeth.
The structural appearance of the enamel and dentin of three extracted and longitudinally sectioned prematurely erupted teeth was investigated with scanning electron microscopy (SEM). The lower incisors were rootless with hypermobility.
The surface of enamel of the prematurely erupted primary teeth was hypoplastic and hypomineralized and had a typical "honeycomb" appearance in SEM. The aprismatic type of enamel was visible in some regions.
The neonatal line separating the layer of prenatal enamel from postnatal enamel was observed. The enamel prisms were connected together by interprismatic substances and cross-striations of prisms were visible.
The dentin presented a typical tubular character. The dentinal layer near the enamel dentin junction had Y-shaped branching of dentinal tubules.
On the pulpal side, the dentin had a globular character. The macroscopic and SEM investigation revealed particularly alterations of the enamel while the dentin of neonatal teeth has nearly normal appearance.