Research On The Relationship Of Dental Crowding And Dental Arch Form And Basal Bone Form

Objective: Through measuring and analyzing the study models of permanent teeth patients with dental crowding,this study is aim to find out the relationship between crowding value and dental arch form and basal bone form. And through multivariate regression analysis of the dental arch form factors to identify a relationship with the crowding index more closely. Providing a more reasonable reference to clinical diagnosis and patient treatment options designed in orthodontics.Methods: 313 cases of crowding dental study model form the first hospital of Hebei medical university meeting the requirements of the newly diagnosed patients as research subjects. Of which 304 cases of maxilla (male 142 cases, female 162 cases,), 313 cases of mandibula (male 146 cases, female 167 cases). The average age of male is 19.2 years, average age of female is 18.9 years. The width of crown, the width and length of the dental arch,the width and length of basal arch were measured in mild crowding group(value2-4mm), moderate crowding group(value4-8mm) and heavy crowding group(value≥8mm). Each study mode measurement three times, the data deviation is less than 0.1mm, The results of calculating the average of three measurements., And into the statistical software, then statistic analysis was got about the sex differences,group differences,correlation analysis and multivariate regression analysis to find the highest and the congestion-related indicators.Results:1 Sex differences:1.1 Maxilla differences:all indicators of mild crowding group, moderate crowding group, middle of the width (WU2), posterior width (WU3), anterior length (LU1), basal bone width (BBUW); heavy crowding group, posterior width (WU3), posterior length (LU3), basal bone width (BBUW), basal bone length (BBUL) were male than female, there was significant difference (P <0.05).1.2 Mandibula differences: in the middle of the width of mild crowding group (WL2), width of post (WL3), basal bone width (BBLW), base bone length (BBLL); width of the moderate crowded group (WL1, WL2, WL3), anterior length (LL1), basal bone width (BBLW), basal bone length (BBLL) for male than female, with significant differences (P <0.05), and severe congestion were no significant differences.2 Groups differences:2.1 The width and length of the basal bone was no significant difference.2.2 Arch width as follows: Except maxilla anterior width (WU1) of male(P>0.05), the other indices showed significant differences (P <0.05). Archlength as follows: Except the mandibula middle length (LL2), mandibular posterior length ( LL3) of male, and maxillary middle length (LU2), posterior length (LL3) of female(P>0.05), the other indices showed significant difference (P <0.05). The difference showed mild crowding group> moderate crowding group> heavy crowding group.3 Correlation analysis between crowding value and dental arch form:The arch width, middle arch length, posterior arch length of male maxilla and the mandibular and anterior arch width, middle arch length of maxilla female have the linear relationship between crowding value. Maxillary female except anterior arch width, middle arch length, the other indices have the linear relationship between crowding value. And showes negative correlation.4 The multivariate regression analysis as follows:In the regression process, each group selected three more relevant indicator of performance and results of men and women is the same. Maxillary relationship as follows: middle arch width, anterior arch length, posterior arch width. Mandibular relationship as follows: anterior arch length, middle arch width, posterior arch width.Conclusion: 1 The dental arch form and basal bone form of crowding patients has sex differences.2 The width and length of the basal bone was no significant difference, and the length and width of dental arch was correlation.3 With the maxilla crowding most closely is the width of the middle arch, and mandibular is anterior arch length.