Dental morphology of 45,XO human females: Molar cusp area, volume, shape and linear measurements

Crown heights in the permanent teeth of 45,X and 45,X/46,XX females

“…This latter finding differs from the present results as we now found significant differences in tooth crown height between the 45,X and 45,X/46,XX females, but not between the 45,X/ 46,XX and control females. Taken together, the previous reports and the present work demonstrate a direct effect of sex chromosome genes on the growth of certain tooth groups [25,27,36], tooth roots and crowns [13,15,25] and the different parts of the tooth crown [12,17,19,37].…”

“…Turner patients, especially 45,X females, have significantly retarded skeletal maturity, while dental maturity and tooth eruption are advanced [5][6][7]. There is also a marked reduction in the mesiodistal and labiolingual dimensions of the permanent and deciduous tooth crowns [5,[8][9][10][11][12][13][14] and there have also been reports of decreased crown heights in the permanent incisors and canines in this syndrome [15]. Varrela et al [11] found that the tooth crowns of 45,X and 45,X/46,XX females (a female with one X cell line and one normal XX line) were almost the same in the mesiodistal direction, while the 45,X/46,XX females had larger crowns in the labiolingual direction.…”

“…Varrela et al [11] found that the tooth crowns of 45,X and 45,X/46,XX females (a female with one X cell line and one normal XX line) were almost the same in the mesiodistal direction, while the 45,X/46,XX females had larger crowns in the labiolingual direction. The reduction in tooth crown size in the mesiodistal and labiolingual dimensions in Turner patients has been shown to be primarily caused by a thinner layer of enamel [16,17], although the crown dimensions may also be affected by the changed crown morphology [12,13,18,19]. Measurements performed on dental casts from individuals with various sex chromosome constitutions [3,19] and on the natural teeth of normal females and males [20] have demonstrated sexual dimorphism in average tooth crown sizes, the Y chromosome having been shown to increase both tooth crown enamel and dentin growth, whereas the effect of the X chromosome seems to be restricted to enamel formation [16,17,[19][20][21][22][23][24].…”

Sexual dimorphism in deciduous crown traits of a European derived Australian sample

“…This may be attributed to the X chromosomes' growth promoting effect on the number of cusps. Turner's syndrome females (X0) have reduced cusp number compared to control females (XX) [61,62]. Furthermore an X-linked gene, ectodysplasin, has been linked to the enamel knot signaling pathways and in the absence of this, humans and mice display reduced cusp number [63,64].…”

The Metric Features of Teeth in Female-to-Male Transsexuals

“…Research on how the genes in both X and Y chromosomes influence the odontogenesis comprised also the analysis of the dental morphology in patients with sex chromosomes disorders. Patients with Turner syndrome (45X) presented smaller teeth and less frequent shoveling of the upper central incisor, reduced frequencies, and expressions of the hypocone and Carabelli's trait in upper molars and hypoconulid in lower molars, compared to healthy women (Alvesalo, 1997;Kari, Alvesalo, & Manninen, 1980;Mayhall & Alvesalo, 1992). Males with 47XYY and 47XXY exhibited bigger teeth than male controls (Alvesalo, Osborne, & Kari, 1975;Alvesalo et al, 1991).…”