In cleft palate(CP), dental enamel anomalies of anterior teeth of both dentition affected by the development of the primary palate was reported. There is rare report about abnormal formation of fetal anterior teeth in still born fetus(SBF) with cleft palate. The purposes of this study were to confirm karyotype of SBF with CP, and to examine the abnormal structures of dental hard tissues in fetal anterior teeth of SBF with CP by Scanning electron microscopy(SEM). For primary culture of fibroblasts, excised buccal mucosa of SBF was cultured under DMEM containing 10% FBS at 37℃ on 95% CO2 incubator. For karyotping, the cultured buccal fibroblasts were treated with colcemid, and warmed 0.075M KCl, fixed with fixative, and stained with 5% Giemsa. After destained with 80-90% alcohol, and aged for 3days at room temperature, G-banding and idiogram were done. For SEM study, bisected fetal teeth were fixed with 4% paraformaldehyde, and examined with SEM. The obtained results were as follows.
1. Karyotype of both dentition showed no abnormal chromosomal structural and number changes.
2. On the 25th week of SBF without CP, the cut surface revealed numerous, regular sized calcospherites(about 0.5 to 3㎛ in diameter) from typical keyhole shaped enamel rod arranged as a honeycomb pattern.
3. On the 33rd week of SBF without CP, there were well organized crystallites, and well enamel prism arrangement with stratified calcified deposits. Enamel thickness were 300 to 600㎛ of coronal area, and 200 to 300㎛ of labial or lingual area. There were typical dentinal tubule with more densly calcified peritubular dentin, and scalloped DEJ.
4. On the 25th week of SBF with CP, there were irregular globular protrusions on honeycomb pattern of enamel surface, and hypoplastic area showed the loss of honeycomb pattern with irregular globular protrusions on enamel surface.
5. On 33rd week of SBF with CP, there were irregular granular crystalline aggregates, irregular arranged enamel prisms, smooth DEJ, and reduced tubular openings. Enamel thickness was about half compared to SBF without CP.
From the aboving results, karyotype of both dentition showed no abnormal chromosomal structural and number changes. It was suggested that fetal anterior tooth of SBF with CP showed hypomaturation and hypocalcification of the dental hard tissue according to calcospherite formation on honeycomb pattern, prism arrangement, dentinal tubular formation and enamel thickness.
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