**4. Dental dimensions**

Among the object of study of dental anthropology in his interest in recording, study, analyze, explain and understand the information provided by the human dentition, such as anatomical variations, developmental, pathological, cultural and therapeutic consideration with living conditions, culture, food and adaptation processes of the past and present human populations, are important the odontoscopia, the odontometry, the oral paleopathology, and modifications of the teeth. Based on this concept extensively reviewed in the literature, the odontometry or registration of dental dimensions should be studied from an interdisciplinary perspective (biology, anthropology, dentistry, paleopathology, archeology, forensics) since the teeth are the precise means to recognize individuals whose death makes it difficult to distinguish by other processes, which are part of the reconstruction of the osteobiography or odontobiography individual and general, contributing just as in estimating biological populations to clarify past its history, origin, training, contacts and movements of the past and present human groups [2,5,6,64].

Sex determination from dental measures has been one of the least developed in physical anthropology. Sex is central to this research and to help determine the taxonomic value of the traits examined [7]. The odontometry and obtaining coronal and root action of the teeth are used in different ways, depending on the interest of the study. In the dental context dimensions of the teeth are useful for the prediction of space for orthodontic treatment and orthodontics. In the anthropological context are used in comparative evolutionary studies and for establishing phylogenetic relationships among species of hominids and disappeared modern humans and to determine biological distances between populations, the same way they are used to diagnose the sex of individuals and complete paleo-demographic information of past populations. Finally, in the forensic context are useful for determining the sex of an individual in the process of identification [6,11].

Worldwide research on this topic has sheltered many of the current populations and a number of past populations, which has contributed to the elucidation of the human evolutionary processes, the population distribution in the continents of Africa, Europe and Asia, the settlement of the Americas, and the formation of population clusters by means of the dimensions of the teeth [28,29,31,40].

114 Sexual Dimorphism

**3.3. Statistical analysis of sexual dimorphism** 

hypothesis in terms of statistical significance [63].

**4. Dental dimensions** 

from lowest to highest, according to the degree of expression [24-27].

Since dental morphological features are analyzed according to their expression (dichotomy presence/absence) and variability (gradation), at the time to categorize the variables for the descriptive statistical analysis, each level of expression of morphological traits constitutes a qualitative ordinal variable, where the observation methods allow to construct scales ranges

To determine the sexual dimorphism are useful univariate nonparametric tests such as Pearson chi-square to measure the discrepancy between observed and a theoretical distribution (goodness of fit), indicating the extent to which differences between the two, if any, are due to chance in the contrast of the assumptions made in this case there is sexual dimorphism, or Mann-Whitney test, applied to two independent samples to test the twosample heterogeneity ordinal under the null hypothesis that the distributions of departure of both distributions is the same, meaning that there is sexual dimorphism in the sample. For both tests, we adopt a p<0.05 in a normal distribution of the sample to reject the null

Among the object of study of dental anthropology in his interest in recording, study, analyze, explain and understand the information provided by the human dentition, such as anatomical variations, developmental, pathological, cultural and therapeutic consideration with living conditions, culture, food and adaptation processes of the past and present human populations, are important the odontoscopia, the odontometry, the oral paleopathology, and modifications of the teeth. Based on this concept extensively reviewed in the literature, the odontometry or registration of dental dimensions should be studied from an interdisciplinary perspective (biology, anthropology, dentistry, paleopathology, archeology, forensics) since the teeth are the precise means to recognize individuals whose death makes it difficult to distinguish by other processes, which are part of the reconstruction of the osteobiography or odontobiography individual and general, contributing just as in estimating biological populations to clarify past its history, origin,

training, contacts and movements of the past and present human groups [2,5,6,64].

the sex of an individual in the process of identification [6,11].

Sex determination from dental measures has been one of the least developed in physical anthropology. Sex is central to this research and to help determine the taxonomic value of the traits examined [7]. The odontometry and obtaining coronal and root action of the teeth are used in different ways, depending on the interest of the study. In the dental context dimensions of the teeth are useful for the prediction of space for orthodontic treatment and orthodontics. In the anthropological context are used in comparative evolutionary studies and for establishing phylogenetic relationships among species of hominids and disappeared modern humans and to determine biological distances between populations, the same way they are used to diagnose the sex of individuals and complete paleo-demographic information of past populations. Finally, in the forensic context are useful for determining Since the simplification of the morphology and tooth size reduction has been the trend in the evolution of hominids, A. Zoubov -cited by J. V. Rodriguez [6]- groups the different hominid groups according to tooth size and explains them in ten points.


5. In the case of modern humans (neoanthropus), tooth size is reduced relative to the Middle Pleistocene hominids, although with differential gradients in various regions of the world, beginning the ethnic variation over the geographic distribution of this condition. This condition increases after the Late Pleistocene, about 100,000 years ago.

Sexual Dimorphism in Human Teeth from Dental Morphology and Dimensions:

thus Australoids are macrodonts. Observed differences between Caucasoid and Negroid are not significant, especially labiolingual diameter of almost all teeth. The differences are more noticeable in mesiodistal diameter, particularly upper lateral incisor, premolar, second molar, mandibular canine, first premolar, first and second lower molar. The largest absolute differences are observed in the mesodistal diameter of the incisors, especially the lateral incisor, and premolars when Caucasoid and Mongoloid are compared. The Negroid reflect minor differences compared with the three major geographic and racial groups. The differences between Mongoloid and Negroid are almost nonexistent, excluding second

The study of dental dimensions of the teeth has shown that these have a high heritability within populations worldwide. The same has been demonstrated in the study of identical twins, which is why the diameters of the crowns of the teeth have been classified as "continuous variations" whose adaptive capacity is largely related to the functions of the stomatognathic system (chewing) and detached so relative influence of the environment [56, 65,66]. Odontometric measures of the crowns of the teeth or metric dental crown traits more under study are meso-distal diameter, defined as the distance between the contact points interproximal mesial and distal and bucco-lingual diameter (lingual for lower teeth), defined as the distance between the highest convexities of the buccal and palatal (lingual) [67], because these dimensions are not affected by the wear caused by attrition during

For the measurements of the diameters methods used are from C. Moorrees et al [68] for meso-distal diameters (distance between the surfaces of contour mesial and distal reference plane having as the occlusal surface), in which the gauge is placed parallel or vertical to the surface occlusal so that the tips locate the areas of the mesial interproximal contact points and distal and from J. Kieser et al [69] for bucco-lingual diameters (distance between the points of greatest convex of the buccal and lingual taking as a reference plane to the occlusal surface), in which the gauge is placed parallel or vertical to the occlusal surface so that the planes of the ends locate the areas of greatest convexity of the buccal and

For individual analysis, with meso-distal dimensions and vestibule-lingual, can be calculated means as the coronal module (sum of the diameters meso-distal and buccolingual divided by two), the coronal index (bucco-lingual diameter multiplied by 100 and divided by the meso-distal diameter), the index of robustness of each tooth (crown area corresponds to the product of the diameters meso-distal and bucco-lingual) and the index of robustness of the dentition ( sum of the indices of strength of all teeth divided by the number of types of teeth taken into account). Similarly, all these measures and indices obtained can be averaged and be applied to population analysis (frequencies, sexual dimorphism, bilateral symmetry, correspondence between metric traits within the same

molars [6].

lingual surfaces.

**4.1. Metric dental traits** 

chewing or the abrasive properties of some foods [6].

kind of teeth and biological distances) [12].

A Dental Anthropology Viewpoint 117


First described by A. Zoubov, J. V. Rodriguez [6] argues that although tooth reduction (downsizing and streamlining of structures) was an evolutionary trend of the dental system of man, should not be understood as the loss of features, as Carabelli's tubercle and styloid formations were acquisitions undertaken in the late stages of the sapientization, as explained by the reduction theory proposed by mutational effect. Added to this, I. Shmalgausen proposes a theory about the accumulation of mutations, which holds that the simplification of the organs is a result of the uncontrolled accumulation of mutations that loosen the correlated systems during ontogenesis, in the case of the teeth, reducing the rate of growth individual body could have generated the reduction of its size, sexual dimorphism even disappearing. Other factors such as genetic isolation could produce increased tooth size, while the hybridization or miscegenation, however, could have generated reduction and simplification of the structures.

From the population point of view, the comparison of dental dimensions of different ethnic groups and those associated with the four major complexes (Australoid, Caucasoid, Mongoloid and Negroid) highlights the specificity of dental size of different populations, thus Australoids are macrodonts. Observed differences between Caucasoid and Negroid are not significant, especially labiolingual diameter of almost all teeth. The differences are more noticeable in mesiodistal diameter, particularly upper lateral incisor, premolar, second molar, mandibular canine, first premolar, first and second lower molar. The largest absolute differences are observed in the mesodistal diameter of the incisors, especially the lateral incisor, and premolars when Caucasoid and Mongoloid are compared. The Negroid reflect minor differences compared with the three major geographic and racial groups. The differences between Mongoloid and Negroid are almost nonexistent, excluding second molars [6].

#### **4.1. Metric dental traits**

116 Sexual Dimorphism

5. In the case of modern humans (neoanthropus), tooth size is reduced relative to the Middle Pleistocene hominids, although with differential gradients in various regions of the world, beginning the ethnic variation over the geographic distribution of this condition. This condition increases after the Late Pleistocene, about 100,000 years ago. 6. Dental size reduction during the Late Pleistocene compared dental size between modern populations, and between the latter and the prehistoric to observe from the perspective of differences in body size, including sexual dimorphism between each

7. This reduction in the Upper Pleistocene dental started long before the present changes in the composition of the diet, but can be correlated with the adoption of new techniques in their preparation and use of earth ovens for cooking food, it that reduced masticatory pressure and relaxed the selection forces that remained stable during the Pleistocene. The resulting tooth reduction was the product of that C. Brace called

8. At the end of the Pleistocene the adoption of ceramics further relaxed selection forces, the beneficiaries of reduced dental system at a rate of 1% per 1,000 years. While during the Pleistocene the rate of reduction was 1% for 100,000 years, after this period was 1%

9. The maximum tooth reduction is presented in a northern strip that extends from the western to the eastern extremity. The present inhabitants of that region are the

10. To the south of the areas with oldest non-use of the teeth in the preparation of food, tooth size increases in proportion to the recent culinary skills. Homo sapiens within the lower tooth reduction are observed among the Australian Aborigines, although used as ovens on the ground for the arrival of Europeans, did not use pottery for

First described by A. Zoubov, J. V. Rodriguez [6] argues that although tooth reduction (downsizing and streamlining of structures) was an evolutionary trend of the dental system of man, should not be understood as the loss of features, as Carabelli's tubercle and styloid formations were acquisitions undertaken in the late stages of the sapientization, as explained by the reduction theory proposed by mutational effect. Added to this, I. Shmalgausen proposes a theory about the accumulation of mutations, which holds that the simplification of the organs is a result of the uncontrolled accumulation of mutations that loosen the correlated systems during ontogenesis, in the case of the teeth, reducing the rate of growth individual body could have generated the reduction of its size, sexual dimorphism even disappearing. Other factors such as genetic isolation could produce increased tooth size, while the hybridization or miscegenation, however, could have

From the population point of view, the comparison of dental dimensions of different ethnic groups and those associated with the four major complexes (Australoid, Caucasoid, Mongoloid and Negroid) highlights the specificity of dental size of different populations,

taxonomic group, more evident in the canine teeth.

descendants of the first people to cook food.

generated reduction and simplification of the structures.

probable mutational effect.

for 1,000 years.

cooking food.

The study of dental dimensions of the teeth has shown that these have a high heritability within populations worldwide. The same has been demonstrated in the study of identical twins, which is why the diameters of the crowns of the teeth have been classified as "continuous variations" whose adaptive capacity is largely related to the functions of the stomatognathic system (chewing) and detached so relative influence of the environment [56, 65,66]. Odontometric measures of the crowns of the teeth or metric dental crown traits more under study are meso-distal diameter, defined as the distance between the contact points interproximal mesial and distal and bucco-lingual diameter (lingual for lower teeth), defined as the distance between the highest convexities of the buccal and palatal (lingual) [67], because these dimensions are not affected by the wear caused by attrition during chewing or the abrasive properties of some foods [6].

For the measurements of the diameters methods used are from C. Moorrees et al [68] for meso-distal diameters (distance between the surfaces of contour mesial and distal reference plane having as the occlusal surface), in which the gauge is placed parallel or vertical to the surface occlusal so that the tips locate the areas of the mesial interproximal contact points and distal and from J. Kieser et al [69] for bucco-lingual diameters (distance between the points of greatest convex of the buccal and lingual taking as a reference plane to the occlusal surface), in which the gauge is placed parallel or vertical to the occlusal surface so that the planes of the ends locate the areas of greatest convexity of the buccal and lingual surfaces.

For individual analysis, with meso-distal dimensions and vestibule-lingual, can be calculated means as the coronal module (sum of the diameters meso-distal and buccolingual divided by two), the coronal index (bucco-lingual diameter multiplied by 100 and divided by the meso-distal diameter), the index of robustness of each tooth (crown area corresponds to the product of the diameters meso-distal and bucco-lingual) and the index of robustness of the dentition ( sum of the indices of strength of all teeth divided by the number of types of teeth taken into account). Similarly, all these measures and indices obtained can be averaged and be applied to population analysis (frequencies, sexual dimorphism, bilateral symmetry, correspondence between metric traits within the same kind of teeth and biological distances) [12].

#### **4.2. Sexual dimorphism and bilateral symmetry**

With respect to sexual dimorphism, different authors claim that the size of the teeth is genetically determined in about 90% (64% in mesodistal diameter), so they are not affected by nutritional status or the environment. In contemporary populations has been shown that the average dimorphism with respect to meso-distal diameter is 3.1%, being canine the most dimorphic tooth. Also has been shown, from the point of view of the correspondence between the teeth of the same class that distal teeth (lateral incisor, second premolar and second molar) are the most variable [6].

Sexual Dimorphism in Human Teeth from Dental Morphology and Dimensions:

Promedio Standard

9.661 .6957

deviation

Meso-distal diameters Bucco-lingual diameters

Sexual dimorphism (*p*<0.05]

UI1 Mujeres 8.368 .4619 .037 7.264 .6584 .282 Hombres 8.653 .6211 7.068 .7690

UI2 Mujeres 6.879 .5750 .925 6.436 .7607 .505 Hombres 6.892 .5749 6.313 .7133

UP1 Mujeres 7.193 .7707 .779 9.679 .6641 .647 Hombres 7.257 .7808 9.608 .5810

UM1 Mujeres 10.189 .5500 .902 11.246 .6149 .493 Hombres 10.158 1.2567 11.335 .6479

UI1 Mujeres 8.386 .7204 .176 7.318 .7087 .208 Hombres 8.597 .5380 7.074 .8140

UC Mujeres 8.036 .7004 .425 7.818 .9495 .316 Hombres 7.916 .5144 7.603 .7786

UP2 Mujeres 6.829 .5241 .681 9.646 .7010 .721 Hombres 6.887 .5960 9.700 .5110

UM1 Mujeres 10.179 .5159 .112 11.164 .6510 .097 Hombres 10.418 .6505 11.439 .6559

LI1 Mujeres 5.225 .5001 .606 5.836 .5086 .191 Hombres 5.284 .4265 6.000 .4926

LI2 Mujeres 5.92 .576 .935 6.293 .6475 .520 Hombres 5.91 .442 6.197 .5494

LC Mujeres 6.921 .5833 .617 7.264 .5958 .436 Hombres 6.987 .4743 7.142 .6467

LP1 Mujeres 7.007 .5537 .054 7.929 .6604 .385 Hombres 7.287 .5855 8.063 .5842

LP2 Mujeres 6.971 .6121 .078 11.404 15.2266 .326 Hombres 7.237 .5838 8.521 .5822

LM1 Mujeres 10.789 1.1808 .245 10.421 .6008 .593 Hombres 11.103 .9857 10.526 .8946

LI1 Mujeres 5.304 .3805 .850 5.936 .5599 .637

UP2 Mujeres 6.900 .6128 .545 9.629 .6259

7.754 1.0401 .804 Hombres 7.908 .5753 7.692 .9556

.998 Hombres 7.003 .7198 9.629 .5229

6.496 .7167 .314 Hombres 6.871 .6004 6.311 .7479

.958 Hombres 7.197 .4857 9.653 .5559

Teeth Gender

Promedio Standard

UC Mujeres 7.929 .7164 .897

UI2 Mujeres 6.911 .6057 .792

UP1 Mujeres 7.225 .4956 .822

deviation

A Dental Anthropology Viewpoint 119

Sexual dimorphism (*p*<0.05]

The study of dental dimensions has been used to understand sexual dimorphism in the socio-ecological and phylogenetic primate evolution. Sexual dimorphism is defined as an intraspecific difference between men and women, which can be studied from the somatotype of the individual, the size and dental morphology, and correlated with patterns of intrasexual competition. During evolution, there have been ontogenetic mechanisms that cause morphological differences between males and females during primate evolution. The ontogenetic changes in these processes lead to the existence of sexual dimorphism associated with the size and evolutionary response to various factors including territoriality, competition and the distribution of resources. However, in modern humans, the restriction of many of these factors has caused the sexual dimorphism of tooth size has almost disappeared, except perhaps in the canine teeth [70].

The meso-distal and bucco-lingual teeth diameters from 100 Americans and 100 Caucasian Americans of African descent, stating that sexual dimorphism is 1.2% of the sample, while the differences between the two ethnic groups was 4.9%. The results allowed concluding that there were no significant differences between these two variables and it is difficult to establish lines of analysis given the large intra-group variations. S. Paulino et al [71] studied the dental dimensions in 153 models (115 women and 38 men) and found that there is a significant difference in the meso-distal diameter between women and men, being higher in the latter. M. Ates et al [72] determined the meso-distal and bucco-lingual diameters in a sample of 100 Turks (50 men and 50 women) and concluded that there is no sexual dimorphism in the observed sample. I. Suazo et al [73] reported that in all the permanent teeth of 150 Chilean individuals (67 men and 83 women), meso-distal and bucco-lingual diameters are higher in men, but these differences are not significant and therefore are not can consider the existence of sexual dimorphism. Astete et al [74] compared two samples of Spanish and Chilean concluding that the diameters from meso-distal and vestibulo-lingual, has a greater sexual dimorphism in Spanish than Chileans, however this difference was not statistically significant. L. Castillo et al [75] in a Colombian sample of mixed Caucasians, concluded that the meso-distal and bucco-lingual diameters are not sexually dimorphic, which was associated with the disappearance of the selective pressure of the dimorphic characteristic strength between men and women. Also these authors observed no differences in bilateral symmetry with respect to sex in the diameters of the right and left teeth in the same class, which highlights the degree of conservation of this property and its clinical significance for dental diagnosis and treatment (Table 3).

Sexual Dimorphism in Human Teeth from Dental Morphology and Dimensions: A Dental Anthropology Viewpoint 119


118 Sexual Dimorphism

**4.2. Sexual dimorphism and bilateral symmetry** 

disappeared, except perhaps in the canine teeth [70].

significance for dental diagnosis and treatment (Table 3).

second molar) are the most variable [6].

With respect to sexual dimorphism, different authors claim that the size of the teeth is genetically determined in about 90% (64% in mesodistal diameter), so they are not affected by nutritional status or the environment. In contemporary populations has been shown that the average dimorphism with respect to meso-distal diameter is 3.1%, being canine the most dimorphic tooth. Also has been shown, from the point of view of the correspondence between the teeth of the same class that distal teeth (lateral incisor, second premolar and

The study of dental dimensions has been used to understand sexual dimorphism in the socio-ecological and phylogenetic primate evolution. Sexual dimorphism is defined as an intraspecific difference between men and women, which can be studied from the somatotype of the individual, the size and dental morphology, and correlated with patterns of intrasexual competition. During evolution, there have been ontogenetic mechanisms that cause morphological differences between males and females during primate evolution. The ontogenetic changes in these processes lead to the existence of sexual dimorphism associated with the size and evolutionary response to various factors including territoriality, competition and the distribution of resources. However, in modern humans, the restriction of many of these factors has caused the sexual dimorphism of tooth size has almost

The meso-distal and bucco-lingual teeth diameters from 100 Americans and 100 Caucasian Americans of African descent, stating that sexual dimorphism is 1.2% of the sample, while the differences between the two ethnic groups was 4.9%. The results allowed concluding that there were no significant differences between these two variables and it is difficult to establish lines of analysis given the large intra-group variations. S. Paulino et al [71] studied the dental dimensions in 153 models (115 women and 38 men) and found that there is a significant difference in the meso-distal diameter between women and men, being higher in the latter. M. Ates et al [72] determined the meso-distal and bucco-lingual diameters in a sample of 100 Turks (50 men and 50 women) and concluded that there is no sexual dimorphism in the observed sample. I. Suazo et al [73] reported that in all the permanent teeth of 150 Chilean individuals (67 men and 83 women), meso-distal and bucco-lingual diameters are higher in men, but these differences are not significant and therefore are not can consider the existence of sexual dimorphism. Astete et al [74] compared two samples of Spanish and Chilean concluding that the diameters from meso-distal and vestibulo-lingual, has a greater sexual dimorphism in Spanish than Chileans, however this difference was not statistically significant. L. Castillo et al [75] in a Colombian sample of mixed Caucasians, concluded that the meso-distal and bucco-lingual diameters are not sexually dimorphic, which was associated with the disappearance of the selective pressure of the dimorphic characteristic strength between men and women. Also these authors observed no differences in bilateral symmetry with respect to sex in the diameters of the right and left teeth in the same class, which highlights the degree of conservation of this property and its clinical


Sexual Dimorphism in Human Teeth from Dental Morphology and Dimensions:

[1] Rodríguez JV. Introducción a la antropología dental. Cuadernos de antropología. 1989;

[2] Scott GC, Turner II CG. The anthropology of modern human teeth: dental morphology and its variation in recent human populations. First published. London: Cambridge

[3] Moreno F, Moreno SM, Díaz CA, Bustos EA, Rodríguez JV. Prevalencia y variabilidad de ocho rasgos morfológicos dentales en jóvenes de tres colegios de Cali, 2002. Colomb

[4] Hochrein MJ. Buried crime scene evidence: the application of forensic geotaphonomy in forensic archaeology. In forensic dentistry, Stimson PG, Mertz CA, editors. First edition.

[7] Rodríguez CD. Antropología dental prehispánica: variación y distancias biológicas en la población enterrada en el cementerio prehispánico de Obando, Valle del Cauca,

[8] Rodríguez CD. La antropología dental y su importancia en el estudio de los grupos

[9] Rodríguez CD. La antropología dental y su importancia en el estudio de los grupos

[10] Marín L, Moreno F. Odontología forense: identificación odontológica, reporte de casos.

[11] Rodríguez JV. La antropología forense en la identificación humana. Universidad

[14] Mayhall JT. Dental morphology: techniques and strategies. In Biological anthropology of the human skeleton, katzenberg MA, Saunders SR (Editors). Willey-Liss, New York.

[17] Hanihara, K. Mongoloid dental complex in the deciduous dentition. J Anthrop Soc

[18] Sciulli PW. Evolution of Dentition in Prehistoric Ohio Valley Native Americans: II. Morphology of the Deciduous Dentition. Am J Phys Anthropol 1998; 106:189-205. [19] Grine FE. Anthropological Aspects of the Deciduous Teeth of African Blacks. En Singer L y Lundy JK (Eds) Variation, Culture and Evolution in African Populations.

Johanessburg: Witwatersrand University Press. 1986. p 47-83.

[12] Hillson S. Dental anthropology. First edition. London: Cambridge University Press; 1996. [13] Alt KW, Rosing FW, Teschler-Nicola M. Dental anthropology: fundamentals, limits, and

[15] Zoubov AA. La antropología dental y la práctica forense. Maguaré 1998; 13:243-252. [16] Turner II CG, Nichol CR, Scott GR. Scoring procedures for key morphological traits of the permanent dentition: the Arizona State University dental anthropology system. In Nelly MA, Larsen CS (editors). Advances in dental anthropology. New York: Wiley-Liss

[5] Scott GC, Turner II CG. Dental anthropology. Ann Rev Antrophol 1998; 17: 99-126. [6] Rodríguez JV. Dientes y diversidad humana: avances de la antropología dental. Primera

edición. Santa Fe de Bogotá: Universidad Nacional de Colombia; 2003.

Colombia entre los siglos VIII y XIII d.C. Syllaba Press. Miami. 2003.

humanos. Rev Fac Odont Univ Ant 2005; 16(1 y 2): 52-59.

humanos prehispánicos. Revista de Antropología Experimental 2004; 4.

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Rev Estomat 2003: 11(2):41-49.

2000. p. 103-134.

Inc; 1991. p. 13-31.

Nippon 1966; 74: 9-20.

Nacional de Colombia. Bogotá. 2004.

prospects. New York: Springer-Verlag; 1998.

London: CRC Press; 1997.

A Dental Anthropology Viewpoint 121

**Table 3.** Sexual dimorphism of the metric dental traits al the comtemporary colombian Caucasian mestizo population

#### **4.3. Statistical analysis of sexual dimorphism**

Since dental metric traits analyzed according to their measure and subsequently grouped into averages or means and standard deviations are obtained at the time to categorize the variables for the descriptive statistical analysis, each degree of expression of metric traits constitutes a quantitative ratio variable, where the observation methods for determining the measure in terms of metric units [39].

To determine the sexual dimorphism are useful parametric tests such as Student's t test to prove a hypothesis, which in this case means that if there is sexual dimorphism. It comes from a probability distribution that arises from the problem of estimating the mean of a normally distributed population when the sample size is small, considering that the observations must be independent and must be performed on normally distributed population universes whose variances groups should be homogeneous, which is not true for meso-distal diameters and vestibule-lingual, so it is necessary to previously apply the Kolmogorov-Smirnov test to determine normality and Levene to determine equality of variances . For this test, we adopt a p <0.05 in a normal distribution of the sample to reject the null hypothesis in terms of statistical significance [63].
