| Objectives : To analyze the soft and the hard tissue profile characteristic in the early permanent dentition with Classâ… ,â…¡divisionl,â…¢malocclusion in DaLian JinZhou district by cephalometrics and chooseseveral soft tissue variables as the indexes for assessing esthetics of facial profile,we can make diagnosis and treatment plan for malocclusion.Methods:Through general investigation for 2000 primary and middle school students with the early permanent dentition in DaLian JinZhou district,we choose 50 students with harmony profile (25 male,25 female,with average age of 12.36).in addition,50(25 male, 25 female,with average age of 12.82)were Classâ… malocclusion;50(25 male,25 famale,withaverage age of 13.04)were Classâ…¡,divisionl malocclusion,50(25 male,25 female,with average age of 12.96)were Classâ…¢malocclusion,therefore,200children were enrolled into the study.All these children were examined cephalometrially with the lip at rest.26 soft tissue variables and 15 hard tissue variable were selected and the cephalometric data of four groups were analyzed statistically by using SPSS11.5 software.Results:1.Compared with the normal occlusion group by ANOVA,in the Classâ… malocclusion group all the hard tissue variables wasn't statistically significant and 2 soft tissue variables were statistically significant (p<0.05) . The indexes which may represent the prime facial profile characteristic of Classâ… malocclusion were selected through discriminant analysis.They were Lower lip to H, Sn-Gns/C-Gns,which constituting the discriminant formula : Y=0.746(Lower lip to H)+4.373(Sn-Gns/C-Gns) -6.629,The contribution of these two indexes to discriminant analysis decreased successively and.Pearson correlation analyses showed there was correlation between the hard tissue variables and Lower lip to H,they were:SNA,ANB,NA/PA,L1-NB,L1/NB,A-NPo,U1/L1,FMIA;we did not find correlation between Sn-Gns/C-Gnsand the hard tissue(p<0.05).2.Compared with the normal occlusion group by ANOVA,12 soft tissue variables and 7 hard tissue variables was statistically significantin the Class II malocclusion group (p<0.05).The indexes which may represent the prime facial profile characteristic of Classâ…¡malocclusion were selected through discriminant analysis. They were Superior sulcus depth,Lower lip to H, G-Pos(HP), Sn-Gns/C-Gns, which constituting the discriminant formula:Y=1.249(Superior sulcus depth)+0.207(Lower lip to H)+0.018(G- Pos(HP))+10.228(Sn-Gns/C-Gns)-22.194,and the discriminant efficiency was 87% . Pearson correlation analyses showed there was correlation between the hard tissue variables and the Superior sulcus depth, they were.SNB,FMIA,ANB,NAPA,A-NPo;correlation between the hard tissue variables and the Lower lip to H,they were U1-NA,L1-NB,L1/NB,MP/FH,U1/L1,FMIA;correlation between the hard tissue variables and the G-Pos(HP),they were SNA,SNB,FMIA,ANB,NA/PA,L1-NB,L1/NB,MP/FH , A-NPo;correlation between the hard tissue variables and theSn-Gns/C-Gns,they were SNA,U1-NA (p<0.05).3.Compared with the normal occlusion group by ANOVA,11 soft tissue variables and 10 hard tissue variables was statistically significant in the Classâ…¢malocclusion group (p<0.05).The indexes which may represent the prime facial profile characteristic of Classâ…¢malocclusionwere selected through discriminant analysis.They were Lower lip to H,Sn-Gns/C-Gns,NsPos,Inferior sulcus to H,which constituting the discriminant formula:Y=2.276(LowerliptoH)+15.945(Sn-Gns/C-Gns)+13.772(NsPos)-0.463(Inferior sulcus to H)-677.179,and the discriminant efficiency was 94%.We did not find the correlation between the Lower lip to H and Sn-Gns/C-Gns with all the hard tissue variables;correlation between the hard tissue variables and the NsPos,they were SNB,FMIA,ANB,NA/PA,L1-NB,L1/NB,L1/MP,MP/FH,FH/NP;correlation between the hard tissue variables and the Inferior sulcus to H,they were U1-NA,FH-NP,MP/FH (p<0.05). Conclusions:1.Got part of the soft and the hard tissue variables of the normal early permanent dentition in DaLian JinZhou district.2.Through discriminant analysis, Lower lip to H,Sn-Gns/C-Gns were selected as two indexes which may represent the abnormality of facial profile of Classâ… malocclusion.3.Superior sulcus depth,Lower lip to H,G-Pos(HP),Sn-Gns/C-Gns were selected asfour indexes which may represent the abnormality of facial profile of Classâ…¡divisionl malocclusion.4.In Class III malocclusion,Lower lip to H,Sn-Gns/C-Gns,NsPos,Inferior sulcus to H were selected as four indexes to assess esthetics of facial profile.5.The discriminant formulae which were constituted by these indexes was useful to diagnose the abnormality of Classâ… ,â…¡divisionl ,â…¢malocclusion profile and assess the treatment effect respectively.6.The hard tissue variables were relavant to the facial profile indexes,indicating the soft tissue profile will be harmonious by the treatment of inharmonious hard tissue. |
PDF Full Text Request