Odontomas showed two types in histopathologic features of decalcified sections, compound and complex odontomas. The disadvantage of decalcifeied study was as follows. The empty space remains after enamel loss by demineralization. There was inaccurate assesment of the degree of mineralization and the loss of the intimate neighboring cellular components. The purpose of this study was to examine the structures, mineralization and calcification of the dental hard tissues in odontomas.
We used 2 cases of normal human molar tooth, 3 cases of compound odontoma(CO), and 5 cases of complex odontoma(CX), which was fixed with 10% neutral buffered formalin, decalcified, and stained with H&E for diagnosis. For undemineralized resin sections, specimens were fixed in 10% buffered neutral formalin, dehydrated by 70-80% alcohol and aceton, and embedded with Spurr low viscosity resin. 500㎛ resin sections were cut by low speed diamond wheel saw, grinded up to 100-200㎛, and examined by LM and PM. We examined mineralization degree by REM, and got a qualitative analysis of Ca, P, and Mg deposition by EPMA, using 100㎛ carbon coated resin sections. The obtained results were as follows
1. In demneralized sections, there were prismatic enamel matrix covered with basophilic laminated material and reduced enamel epithelium, and was bulky intermingled dentin formation.
2. In undemineralized sections of COs, there was absence of H?nter-Schreger band, but presence of Retzius line, enamel lamella and tuft, and variable thickness of enamel, while in CXs, there were absence of all structure, and intermingled enamel and dentin.
3. REM showed uneven dentin covered by rugged enamel surface of odontomas or free enamel dentin. Dentin of CXs in relatively large quantities formed the bulk of tumor with irregular enamel and cementum in small quantities.
4. EPMA analysis showed lower Ca and P deposition in enamel and dentin of odontomas than that of normal molar tooth. It was higher Mg deposition in enamel of COs than that of CXs, and similar or slight higher Mg deposition in dentin of COs than that of CXs.
From the aboving results, it was suggested that the enamel of compound odontoma could be more hypocalcified than that of complex odontoma, while complex odontoma could be more hypomaturated than compound odontoma.
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