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Una comparación morfométrica de molares mandibulares entre chinos Han y malayos basada en tomografía computarizada de
Jacob John1, Wei Cheong Ngeow2, Ting-Chun Shen3
1Department of Restorative Dentistry, Faculty of Dentistry, Universiti of Malaya, Kuala Lumpur, Malaysia.
Journal of dental sciences
|January 26, 2026
Resumen
Los malayos presentan ratios significativamente más altos de dientes y raíz-corona (RCR) en molares mandibulares en comparación con los chinos Han. Sin embargo, los chinos Han muestran una mayor ratio raíz-mandíbula (R: Mand) en M2 debido a una menor altura mandibular.
Área de la Ciencia:
- Antropología
- Odontología
- Genética
Sus antecedentes:
- Las variaciones étnicas en la morfología dental y mandibular son significativas.
- Estas variaciones tienen implicaciones para la práctica clínica y los estudios antropológicos.
Objetivo del estudio:
- Comparar la longitud dental y la ratio raíz-corona (RCR) de los primeros (M1) y segundos (M2) molares mandibulares entre chinos Han y malayos.
- Evaluar la longitud de la raíz en relación con la altura mandibular (Ratio Raíz-Mandíbula o R: Mand) en estos grupos étnicos.
Principales métodos:
- Se utilizaron 121 escaneos de tomografía computarizada de haz cónico (CBCT) (60 chinos Han, 61 malayos).
- Se midieron las longitudes de la corona y la raíz anatómicas y clínicas utilizando software CBCT.
- Se calcularon la RCR y la R: Mand, promediando las mediciones de las raíces mesial y distal.
Principales resultados:
- Los malayos mostraron una morfometría dental y ratios raíz-corona (RCR) significativamente más altas que los chinos Han, excepto para la RCR clínica (c-RCR) de M2.
- M1 generalmente tuvo parámetros más grandes que M2.
- Los chinos Han tuvieron una R: Mand significativamente más alta en M2 (50,69%) debido a una menor altura mandibular, a pesar de una altura mandibular M1 similar entre los grupos.
Conclusiones:
- Las diferencias morfométricas observadas entre chinos Han y malayos pueden deberse a factores genéticos y/o ambientales.
- Estas diferencias podrían afectar la morfología facial y la oclusión en la odontología clínica.
Palabras clave:
tomografía computarizada de haz cónicochino Hanmalayosmolar mandibularmorfometríaratio raíz-coronaMás Videos Relacionados
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