Why do black people have big lips

Upper lip length mm ; 4. Upper lip protrusion mm ; 5. Lower lip protrusion mm ; 6. Upper lip thickness mm ; 7.

Lower lip thickness mm ; 8. Interlabial gap mm ; 9. Upper lip-E mm ; Lower lip-E mm ; Line E Ricketts esthetic plane. The mean and standard deviation SD for the ages and for each variable were calculated for both groups. Normal distribution was verified by the Kolmogorov-Smirnov test. The results of the tests were non-significant for all variables. Therefore, intergroup comparisons were performed by independent t tests.

All statistical analyses were performed on Statistica software Statistica for Windows 6. After 1-month interval from the first measurement, thirty randomly selected cephalograms were retraced and re-measured by the same examiner LMAF.

The random errors varied from 0. GoGn to 0. Only one angular variable SN. Ocl and two linear variables 1-NB and UL thickness presented statistically significant systematic errors.

From the 28 measured evaluated, only two presented systematic errors: SN. Ocl and 1-NB Table 1. These results demonstrated that These errors were comprehensible, because it is known that there is great variation in the determination of the mandibular incisor root apex. Black subjects presented a significantly more protruded maxilla and mandible and a greater maxillomandibular anteroposterior discrepancy than white subjects which had a more vertical growth pattern. Chin prominence was larger in whites.

Facial convexity was greater in blacks than in whites. The maxillary and mandibular incisors were more protruded and proclined in black subjects. The nasolabial angle was greater in whites than in blacks. The upper lip was longer and both upper and lower lips were significantly more protruded in blacks in relation to white subjects. And all of these differences were statistically significant Table 2.

There are many studies in both black and white ethnic groups, but no one compares the skeletal, dentoalveolar and soft tissue characteristics in white and black Brazilians with normal occlusion. Furthermore, problems that can be identified when comparing cephalometric studies of white or black subjects are the cephalometric measurements used, differences in sample size and age, selection criteria, statistical methods, definitions of clinical normality, definitions of the black racial designation and variation in geographic distribution and origin of these two ethnic groups 16 , This way, subjects of the two ethnic groups evaluated in this study were selected from the same geographic boundary, and parents of each subject must be from the same ethnic group.

All sample presented normal occlusion and wellbalanced faces. Additionally, the groups were compatible regarding gender and age distribution Table 2.

Black subjects with normal occlusion presented statistically significant more protruded maxilla and mandible than white subjects with normal occlusion Table 2. Several previous studies also found maxillary and mandibular prognathism in black subjects 2 - 4 , 11 , 17 , Anterior cranial base length can influence the anteroposterior position of nasion and therefore can affect the values of angles SNA and SNB, and this should be considered when comparing two different ethnic groups. The present study also found significant results for the variables A-Nperp and P-Nperp, confirming the bimaxillary skeletal prognathism of the black sample.

However, other studies did not find a statistically significant mandibular prognathism in black individuals, but the maxillary prognathism was also observed 5 , 8 , These controversies may be due to differences in ethnical origins of the samples.

Despite the greater mandibular protrusion observed in blacks, they presented smaller chin prominence when compared to whites, as indicated by P-NB Table 2.

The maxillomandibular relationship presented larger values for blacks in relation to whites and it is in agreement with most of the previous studies 3 , 5 , 11 , 12 , 20 Table 2. Even though the SNB angle was larger in blacks than in whites, it was not large enough to compensate for the large SNA angle, resulting in the larger ANB difference found for black subjects The wits appraisal did not show significant difference between black and white subjects.

Some studies had reported that blacks tend to present shorter anterior cranial base, when compared to whites 2 , 4 , This way, relative to nasion it was expected that the maxilla point A and mandible point B were more anteriorly positioned in blacks than in whites.

But, when the maxillomandibular relationship was evaluated in relation to the occlusal plane, there was no difference between blacks and whites, corroborating some previous studies 5 , 11 , Blacks presented a more horizontal craniofacial growth pattern than whites for all vertical component measurements.

This result is in agreement with the results reported by Dandajena and Nanda 11 , when evaluating a Zimbabwean sample. Some previous studies found that black Americans 6 , 9 , 12 , 28 and Africans 2 , 4 , 20 had a high Frankfort-mandibular plane angle FMA.

Differences from these studies to the present results emphasize the importance of different cephalometric norms for each ethnic group from distinct geographic origins. Regarding the dentoalveolar characteristics, black subjects presented more protruded and proclined maxillary and mandibular incisors than white subjects in all angular and linear incisor variables corroborating previous studies that found a bimaxillary dentoalveolar protrusion 2 , 4 , 5 , 11 , 12 Table 2. Nevertheless, some studies demonstrated only a greater labial inclination of the mandibular incisors and not for the maxillary incisors in blacks, in relation to whites 16 , The black Brazilian subjects present greater tendency to present dental protrusion, when compared to whites, probably due to the greater African miscegenation in Brazil, in these individuals of African descent.

This way, the greater maxillary skeletal prognathism compared to mandibular, as excessive buccal inclination and protrusion of the mandibular incisors, associated to a retropositioning of the chin, are the compensatory effects in order to maintain the incisal contact, in the Black group The protrusion of the maxillary and mandibular incisors found in black individuals appears to compensate for the maxillary and mandibular prognathism, and for the deficient maxillomandibular relationship in order to maintain incisal contact Furthermore, this dental protrusion is more pronounced in mandibular incisors, compensating the smaller mandibular protrusion and chin prominence in this ethnic group.

White subjects with normal occlusion presented a greater nasolabial angle than black subjects with normal occlusion, which presented greater upper lip length and protrusion and lower lip protrusion Table 2.

This indicates a greater soft tissue projection in blacks, as already mentioned previously 2 , 12 , 16 , In the present study, thickness of upper and lower lips was not found to differ between black and white groups. Most significant soft tissue measurements were the protrusion of upper and lower lips found in blacks when compared to whites, which reflected the protrusive pattern of skeletal and dental structures.

These increased values for upper and lower lips protrusion reflect the bimaxillary dentoalveolar protrusion found in black individuals 2 , 4 , 11 , 12 , 20 , which does not mean that there is also a greater soft tissue thickness 17 , as demonstrated in the present results.

The esthetic facial lines and respective parameters differ in different ethnic groups, establishing individualized soft tissue measurements The compensatory dentoalveolar mechanisms provide a balanced face in distinct groups, different by age, race or gender Potentially orthodontic patients have a variety of profile preferences, which indicates a distinction in several facial characteristics within each ethnic group, and the contemporary concept of pleasant esthetics of the facial profile is even more subjective 21 , 23 , The present study confirmed the bimaxillary skeletal, dentoalveolar and soft tissue protrusion observed in black subjects, which have been described by several authors 2 , 4 , 8 , 11 , 15 , 16 , 20 , This dentoalveolar protrusion found in blacks is more evident in the mandibular incisors, compensating the slightly smaller protrusion of the mandible and the smaller chin prominence in this ethnic group.

As expected, blacks showed greater upper and lower lip protrusion 2 , 12 , However, thickness of upper and lower lips was unexpectedly similar in both groups.

This reaffirms that the greater soft tissue projection in blacks is actually a consequence of protruded maxillary and mandibular incisors. The null hypothesis was rejected, because black and white young Brazilian subjects with normal occlusion showed different cephalometric characteristics.

Black Brazilian subjects with normal occlusion presented a more protruded maxilla and mandible, a smaller chin prominence, a greater maxillomandibular discrepancy, a more horizontal craniofacial growth pattern and more protruded and proclined maxillary and mandibular incisors than white Brazilian subjects with normal occlusion. Upper and lower lips were more protruded in blacks, but lip thickness was similar in both groups.

Want to bookmark your favourite articles and stories to read or reference later? Start your Independent Premium subscription today. Already subscribed? Log in. Forgotten your password? Want an ad-free experience? Besides assessing the facial attractiveness, the evaluators had to identify the structures responsible for the classification as unpleasant and pleasant.

Intraexaminer agreement was assessed by using Spearman's correlation, correlation within each category using Kendall concordance coefficient, and correlation between the 3 categories using chi-square test and proportions.

Most of the frontal The structures most identified as esthetically unpleasant were the mouth, lips, and face, in the frontal view; and nose and chin in the profile view. The structures most identified as esthetically pleasant were harmony, face, and mouth, in the frontal view; and harmony and nose in the profile view.

The ratings by the examiners in the sample and laymen groups showed statistically significant correlation in both views. The orthodontists agreed with the laymen on the evaluation of the frontal view and disagreed on profile view, especially regarding whether the images were esthetically unpleasant or acceptable. Based on these results, the evaluation of facial attractiveness according to the Subjective Facial Analysis criteria proved to be applicable and to have a subjective influence; therefore, it is suggested that the patient's opinion regarding the facial esthetics should be considered in orthodontic treatmentplanning.

In Orthodontics, diagnosis is made on the basis of anamnesis; clinical examination; facial, cephalometric and cast models analysis. The facial analysis is reported in the literature since Angle 1 1. Angle EH. Classification of malocclusion. Dent Cosmos. Treatment of malocclusion of the teeth.

Angle's system. Philadelphia: S. White; Herzberg BL. Facial esthetic in relation to orthodontic treatment. Angle Orthod. Hambletom RS. The soft tissue covering of the skeletal face as related to orthodontic problems. Am J Orthod. Dierkes JM. The beauty of the face: an orthodontic perspective. J Am Dent Assoc. Since the advent of cephalometry, lateral radiographs of the face are being used to analyze the facial profile. Burstone CJ. Integumental contour and extension patterns. Neger M, Newark NJ.

A quantitative method for the evaluation of the soft-tissue facial profile. Further, soft tissue analysis shows individual and race variations in facial profiles. Downs WB. Analysis of the Dentofacial Profile. Cunningham MR. Measuring the physical in physical attractiveness: quasi-experiments on the sociobiology of female facial beauty. J Pers Soc Psychol. J Bras Ortodon Ortop Facial. Studies evaluating lateral radiographs of the face 11 Peck H, Peck S. A concept of facial esthetics.

Thomas RG. An evaluation of the soft-tissue facial profile in the North American black woman. A comparison of skeletal, dentoalveolar and soft tissue characteristics in white and black Brazilian subjects. J Appl Oral Sci. Similarly, another study 11 Sutter and Turley 15 Soft tissue evaluation of contemporary Caucasian and African American female facial profiles. They concluded that the facial profiles of black models and non-models were similar, but those of the Caucasian women were significantly different, with models presenting more prominent lips.

To evaluate the changes in the profiles of black American women, Yehezkel and Turley 16 Yehezkel S, Turley PK.