6533b837fe1ef96bd12a2944
RESEARCH PRODUCT
Incremental lines in root cementum of human teeth: an approach to their ultrastructural nature by microscopy.
Heinz DuschnerV. SchaeferRalf J. RadlanskiHerbert Renzsubject
Materials scienceScanning electron microscopeAnalytical chemistrylaw.inventionOpticsOptical microscopelawMicroscopyMicrotomeHumansBicuspidTooth RootDental CementumMicroscopyMicroscopy Confocalbusiness.industryScanning confocal electron microscopyGeneral MedicineMicrotomyDark field microscopyMicroscopy ElectronTransmission electron microscopyEvaluation Studies as TopicUltrastructureAge Determination by TeethbusinessElectron Probe Microanalysisdescription
In ground sections of human teeth, root cementum shows under the light microscope as alternating, almost concentric, dark and light rings. In paleontology and forensic medicine, the number of these incremental lines or annulations is used to derive the age-at-death of the individual. To find the ultrastructural features underlying these cemental annulations, we used bright-field light microscopy (LM), confocal laser scanning microscopy (CLSM), transmission electron microscopy (TEM), and electron-dispersive x-radiation (EDX) in a scanning electron microscope (SEM). Annulations visible in ground sections of about 100-μm thickness were no longer visible in semi-thin sections (thickness, 1-2 μm) of the same specimen in the same area. The assumption that annulations could be caused by superimposing structures in the depth of field of the light microscope's objective lens was not verified by CLSM. Fiber bundles of higher density than the surrounding matrix in TEM micrographs could not be connected unambiguously with annulations in LM micrographs. After all, the ultrastructural nature of cemental annulations remains an open question.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 1998-02-21 | Advances in dental research |