Variabilidad de las proporciones molares en poblaciones humanas: un abordaje empleando modelos del desarrollo y experimentales / Variability of molar proportions in human populations: insights from developmental models and experiments in mice


  • Lucas A. D´Addona
  • Paula N. Gonzalez
  • Valeria Bernal


Los datos sobre la variación dental interpoblacional y sobre los mecanismos que regulan el desarrollo dental aportados por estudios experimentales aún no han sido integrados en el contexto de investigaciones antropobiológicas. En este sentido, el presente trabajo se propone: a) evaluar la consistencia entre la variación de las proporciones molares en poblaciones humanas que exhiben gran variación en el tamaño dental con las predicciones derivadas de un modelo de desarrollo dental de cascada inhibitoria, y b) analizar el efecto de los factores sistémicos que controlan el crecimiento del organismo sobre las proporciones de los molares inferiores empleando cepas de Mus musculus. Se calcularon las áreas de los molares inferiores mediante los diámetros bucolingual y mesiodistal. La variación interpoblacional en las proporciones M2/M1 y M3/M1 fue concordante con las expectativas derivadas del modelo y la mayoría de los grupos exhibieron una tendencia a la reducción del tamaño en sentido antero-posterior. Asimismo, se observó una asociación significativa y positiva entre el área molar total y las proporciones molares. En los modelos experimentales la alteración del crecimiento por factores sistémicos (subnutrición proteica y reducción de la hormona de crecimiento) resultó en la disminución del área molar total y cambios en las proporciones molares. Estos últimos, consistentes con el incremento del efecto inhibitorio en sentido antero-posterior. En conjunto, los resultados sugieren que la modificación de los factores sistémicos que regulan el área molar total podría conducir a cambios en la proporción de activadores-inhibidores y contribuir a la diferenciación interpoblacional en las proporciones molares.

Palabras clave: Modelo de cascada inhibitoria; tamaño dental; aproximación experimental y comparativa

Data on dental variation among human populations and the mechanisms regulating tooth development elucidated by experimental studies have not yet been integrated in the context of biological anthropology. In this sense, this paper proposes: a) to evaluate the consistency between changes in molar proportions in human populations that exhibit a wide variation in tooth size and the predictions derived from an inhibitory cascade model of dental development, and b) to analyze the effect of the systemic factors controlling the growth of the organism on the lower molars proportions using strains of Mus musculus. The crown area of the mandibular molars was estimated from the bucco-lingual and mesio-distal diameters. The results obtained for human populations showed that the pattern of variation in molar proportions is consistent with expectations derived from the inhibitory cascade model and that most groups exhibit a general trend towards molar size reduction in the antero-posterior direction. Also, a significant positive association between the total molar area and the molar ratios M2/M1 and M3/M1 was observed. In the experimental models, growth alteration caused by systemic factors (protein subnutrition and reduced growth hormone) resulted in a reduction of total molar area associated with changes in molar proportions. The latter are consistent with an increased antero-posterior inhibition. Overall, these results suggest that alterations in the systemic factors that control molar area can produce changes in the proportion of activators and inhibitors, and contribute in turn to inter-population differentiation in molar proportions.

Keywords: Inhibitory cascade model; dental size; experimental and comparative approach                                                       


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D´Addona, L. A., Gonzalez, P. N., & Bernal, V. (2016). Variabilidad de las proporciones molares en poblaciones humanas: un abordaje empleando modelos del desarrollo y experimentales / Variability of molar proportions in human populations: insights from developmental models and experiments in mice. Revista Argentina De Antropología Biológica, 18(1). Recuperado a partir de



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