Maxillary Width In Men And Women With Different Vertical And Sagittal Skeletal Patterns

ObjectivesTo compare maxillary width and hard palate thickness of adult in in men and women with different vertical and sagittal skeletal patterns.Methods241 adults seeking for orthodontic therapies(93 males and 148 females from the ages of 18 to 25 years old)were divided into male and female groups.Male and female subjects were separately divided into 3 sagittal skeletal groups according to APDI value(Class ?<76;Class ? 76-86;Class ?>86)and 3 vertical skeletal groups(low-angle<392;average-angle 392-400;high-angle>400)according to Sum value.A lateral cephalogram and a cone-beam computed tomography(CBCT)were taken for each subject.We measured the parameters to make statistical analysis and compared them among different groups.Bizygomatic width,maxillary width,maxillary cross-arch width,TMJ fossa width,pterygoid width,and hard palatal thickness were recorded in CBCT.Cephalometric descriptions were designed as APDI,Sum angle,ANB angle,anterior cranial base length,posterior cranial base length,saddle angle,and articular angle.Firstly,ANOVA with Tukey tests was used to explore the significance of differences in sagittal and vertical patterns.Secondly,An independent sample t-test was used for detecting upper airway and hyoid position changes between genders.An alpha level of 0.05 was considered statistically significant.Results1.Sagittal skeletal pattern(1)In female,significant differences were observed among the 3 groups in NF,HP,LAC and external TMJ fossa width(P=0.023,0.027,0.040,0.031).Class ? group had the shortest NF(70.67mm),HP(63.81mm),LAC(35.14mm)and external TMJ fossa width(112.50mm),and Class ? group was the next(NF=71.11mm,HP=64.59mm,LAC=36.31mm,external TMJ fossa width=113.18mm).Significant differences in the four descriptions were found between Class ? group and Class ?group,as well as Class ? group and Class ? group(P<0.05).In addition,significant differences in the LAC,NF,HP,external and internal TMJ fossa width were found between Class ? group and Class ? group,as well as Class ? group and Class ? group(P<0.05).(2)In male,significant differences were found in NF,HP,BAC,LAC,external and internal TMJ fossa width as well(P<0.05).Class ? and Class ? males had significantly smaller these descriptions than those of Class ? males(NF=76.27mm,HP=78.19mm,LAC=39.74mm,external TMJ fossa width=123.81mm,internal TMJ fossa width=83.30mm).Significant differences in the LAC,NF,HP,external and internal TMJ fossa width were found between Class ? group and Class ? group,as well as Class ? group and Class ? group(P<0.05).2.Vertical skeletal pattern(1)In female,Descriptive statics for vertical patterns craniomaxillofacial bone width were displayed in Table 9 and Table 11,which showed that BAC,LAC,NF and HP were significantly shorter in high-angle group(NF=69.72mm,HP=64.81mm,BAC=53.68mm,LAC=34.64mm)when compared with low-angle group(NF=72.29mm,HP=67.59mm,BAC=56.43mm,LAC=36.43mm).Moreover,high-angle group had a smallest hard palatal thickness at second premolar level(4.02mm),which was also significantly smaller than that of low-angle group(4.85mm).(2)In male,The results of vertical patterns were similar to female's(Table 10,Table 11),which indicated that high-angle group had a smallest hard palatal thickness at second premolar level and shortest BAC,LAC,NF and HP(NF=72.57mm,HP=65.73mm,BAC=55.51mm,LAC=34.52mm,hard palatal thickness at second premolar level=5.04mm),and the difference between high-angle group and low-angle group was statistically significant(P<0.05).3.Female and maleThe skull base and maxilla morphology for both male and female group were different in three dimensions.(1)Transverse differences were showed in the width of ZZ,NF,HP,BAC,LAC,PW,internal and external TMJ fossa,which were longer in males(NF=74.20mm,HP=67.33mm,BAC=58.78mm,LAC=38.02mm,internal TMJ fossa width=85.30mm,external TMJ fossa width=125.11mm,PW=60.02mm,ZZ=124.66mm).Females had smaller craniomaxillofacial bone width than males.(2)Sagittal differences were showed in anterior cranial base length(SN),posterior cranial base length(SAr),Saddle angle,Articular angle,ANB value and APDI value.SN(66.71mm),SAr(37.46mm)and APDI(83.42°)in male samples were greater than those in female samples.But Saddle angle(124.49°),Articular angle(153.37°)and ANB angle(153.37°)from male samples were smaller than those from female samples.(3)Vertical differences were showed in hard palatal thickness and Sum value.Male subjects had significantly thicker hard palatal thickness(5.59mm,2.81mm)and smaller Sum value(394.25°)than those of female subjects.Conclusions1.Both for male and female samples,bizygomatic width and pterygoid width were not correlated with sagittal patterns and vertical patterns.Maxillary width,to some extent,is correlated with vertical and sagittal skeletal patterns.Insufficient maxillary width would lead to unfavorable anterior-posterior and vertical skeletal types.2.There are differences in the morphology of craniomaxillofacial bone between different genders.Females tend to clockwise rotation of mandible,which remind clinicians their vertical control and temporomandibular disorder risk detecting are crucial.Instead,males have counterclockwise rotation tendency and larger growth increment,as well as longer growth time of mandible,so decision-making of treatment strategies and timing,influence of camouflage treatment predicting are worth noticing.