Related Experiment Videos
The intact surface layer in natural enamel caries and acid-dissolved hydroxyapatite pellets. An X-ray diffraction
Journal of Oral Pathology
|February 1, 1981
Summary
The intact surface layer of enamel carious lesions shows higher apatite crystal crystallinity. This surface layer forms from mineral ions redeposited from deeper lesion areas, enhancing crystal structure.
Area of Science:
- Crystallography
- Dental research
- Materials science
Background:
- Enamel carious lesions involve demineralization and remineralization processes.
- The surface layer of carious lesions plays a crucial role in lesion progression and remineralization.
- Understanding the crystallographic properties of enamel apatite is key to comprehending demineralization and remineralization dynamics.
Purpose of the Study:
- To investigate the crystallographic features of apatite crystals in different histological sites of enamel carious lesions.
- To elucidate the formation mechanism of the intact surface layer in carious enamel.
- To correlate mineral deposition and crystal structural changes during lesion development.
Main Methods:
- X-ray microbeam diffraction was employed to analyze the crystallographic properties of enamel samples.
- Acid-dissolution experiments were conducted on synthetic hydroxyapatite pellets.
- X-ray diffraction analysis was used to assess changes in apatite crystal structure (half-line breadth, integrated peak intensity).
Main Results:
- Apatite crystals in the intact surface layer of carious lesions exhibited higher crystallinity compared to subsurface lesions and unaffected enamel.
- Synthetic hydroxyapatite pellets formed a well-mineralized surface layer in an acidic solution without added calcium and phosphate ions.
- Dissolution of hydroxyapatite pellets led to decreased half-line breadth and increased integrated peak intensities of apatite reflections, indicating improved crystallinity.
Conclusions:
- The intact surface layer of enamel carious lesions is formed by the deposition of mineral ions originating from the dissolution of subsurface lesions.
- This mineral deposition process is associated with an improvement in the crystallinity of apatite crystals, likely due to crystal growth.
- The findings provide insights into the remineralization mechanisms occurring at the enamel surface during caries development.