Avaliação do dimorfismo sexual e da relação entre as características craniofaciais, dos arcos dentários e do músculo masseter na fase de dentição mista

Abstract

Purpose: to evaluate sexual dimorphism and the relationship between craniofacial characteristics, dental arch morphology and masseter muscle thickness in children in the mixed dentition stage. Methods: the study sample comprised 32 children, aged 6-10 years (14♀/18♂) with normal occlusion. Craniofacial characteristics, dental morphology and masseter muscle thickness were evaluated by means of posteroanterior cephalometric radiographs, dental cast evaluation and ultrasound exam, respectively. The results were analyzed using Shapiro-Wilk test, Mann-Whitney/t-test and stepwise linear regression to assess the relation between face width and age, gender, body mass index, masseter thickness, distances between first molars and canines on dental casts (between cusps/ cervical points), nasal, maxillary, mandibular and intermolar widths. Results: masseter thickness showed no significant difference between the sides left/right. The comparison between genders showed significant difference only in face width, being larger in boys. The regression model showed that face width was positively related with body mass index, masseter thickness, mandibular first molar distances (cusps), mandibular canine distances (cervical points), and maxillary intermolar width; and negatively with maxillary (cusps) and mandibular molar distances (cervical points) and mandibular canine distances (cusps). That is, when the other studied variables were considered, the explanatory variable gender did not reach a significant value. Conclusion: in the studied sample, the dimensions of the dental arches and masseter thickness did not differ between boys and girls; moreover, face width showed significant relationship with body mass index, masseter thickness, and dimensions of dental arches; but gender did not contribute significantly to face width variation.

Differences between male and female mandibular length growth according to panoramic radiograph

“…The results of this study are similar to those of Generosos' et al, Marquizin et al, and Liu' et al studies. [24][25][26] Generoso et al conducted a study on 40 male and 40 female puberty ages in Brazil. It revealed that the male mandibular length was greater than that of female in various malocclusion classes.…”

“…24 The longitudinal studies conducted by Weber et al in a Caucasian race sample aged 16-18 years showed that the male mandibular length was longer than that of females. 25 The size of the mandible in female over the age of 14 years is relatively constant, whereas in male it is still increasing. 24,25 The longitudinal studies conducted by Liu et in 48 samples consisting of 24 females and 24 Caucasian race males showed that there were significant differences in mandibular size between males and females.…”

“…25 The size of the mandible in female over the age of 14 years is relatively constant, whereas in male it is still increasing. 24,25 The longitudinal studies conducted by Liu et in 48 samples consisting of 24 females and 24 Caucasian race males showed that there were significant differences in mandibular size between males and females. The size of the male mandible is greater than that of female.…”

Relationship between masseter muscle thickness and overbite values in a Nigerian population

“…This is also supported by previous studies of He et al 25 and Kiliaridis et al 26 who reported that reduced activity of the masseter muscle resulted in thin muscle fibres. However, a previous study by Raadsheer et al 24 in 1999 reported greater thickness on the left side, whereas Raadsheer et al 5 and Marquezin et al 27 found no side differences in the thickness of the muscle in subjects with normal occlusion.…”