Degraded prism sheaths in the transition region of hypomineralized teeth

Nano-scale structure and mechanical properties of the human dentine–enamel junction

“…Further fine details on the apatite crystals and their spatial arrangement with the organic matrix at the DEJ were revealed by TEM. The TEM specimens, measuring 10 µm × 20 µm × 0.1 µm, were produced using the protocol described by Chan et al (2010) from the non-etched enamel that had been mechanically characterized.…”

Molar Incisor Hypomineralization: Morphological, Aetiological, Epidemiological and Clinical Considerations

“…Despite the translucent, normal appearance, the transitional region between the affected and unaffected regions in MIH teeth had weakened prism sheaths which compromised its overall mechanical properties. (Chan et al, 2010) The reason for this is unclear but may be also related to the lack of organization of the enamel crystals due poorly demarcated prism boundaries in the affected regions (Mahoney et al, 2004) and the packing of the crystals seemed to be less tight and less well organized in the porous parts. The borders of the enamel rods were indistinct and the interrods zones hardly visible, or the rods were very thin with wide interrod zones.…”

The use of transillumination in detecting subclinical extensions of enamel opacities

“…In literature, minimal attention was paid to the transition region linking affected and unaffected enamel . This transition zone ranges macroscopically from 0.5 to 0.65 mm.…”

“…On microscopic scale, the large interprismatic spaces as well as the degree of disorganizations of enamel prisms found in hypomineralized enamel, appear to be involved in significantly much lower in the transitional region. Those properties likely contribute to the decreased mechanical properties in term of hardness and modulus of elasticity . However, under the naked eye and in reflected light it has been shown that the transition region appears as translucent and unidentifiable by simple visual inspection.…”