A Preliminary Study On The Characteristics And Related Factors Of Anterior And Posterior Occlusal Plane Of Class ? Malocclusio In Adults

ObjectiveTo study the characteristics of anterior and posterior occlusal plane and the relationship between the occlusal plane and the related teeth and jaws of adult patients with high angle skeletal Class II malocclusion by measuring the occlusal plane,teeth and jaws of the patients with Class II malocclusion.Methods20 individuals with normal occlusion individuals and 20 individuals with high-angle skeletal Class II malocclusion were selected and measured.Some indexs of representing skeletal,dental and occlusal indexs were changed,and the data was analyzed statistically.Independent samples t-test was changed for comparing the normal occlusion individuals group and skeletal Class II malocclusion group.Pearson correlation is changed for comparing the correlation of mandible and occlusal planes and the dental items.Results1.Comparing with the control group,the difference of the cant of the anteriorocclusal plane and the posterior occlusal plane in malocclusion group were found to be evidently larger(P<0.05).2.Comparison of denture between the control group and malocclusion group :the alveolar height of maxillary middle incisor(U1-ppmm),maxillary second premolar(U5'-PPmm)and maxillary first molar alveolar height(U6'-PPmm)were evidently higher than those indexs of the normal group(P< 0 05).The alveolar height(U7'-PPmm)of the maxillary second molar was slightly higher than that of the control group(P> 0 05).The number of mandibular middle incisors and mandibular second premolars(L1'-MP mm,L5-MPmm)was evidently higher than those indexs of the normal group(P< 0.05),and there was a significant difference between the two groups(P< 0.05).There was no significant difference in alveolar height(L6'-MPmm)and alveolar height(L7'-MPmm)between the first mandibular molar and the control group(P> 0.05).3.Comparison of the inclination of upper and mandibular teeth: there was no significant difference in the inclination of maxillary middle incisor(U1-FH?U5-FH)between the two groups(P> 0.05).The maxillary first molars and the second maxillary molars were inclined to the distal and middle relative to the FH plane(U6-FH,U7-FH),and there was significant difference(P< 0.05)between the maxillary first molars and the maxillary second molars(P< 0.05).The mandibular second molar(L7'-MP)inclined to the distal and middle,and there was a evident difference(P<0.05).The mandibular middle incisors,mandibular second premolars,mandibular first molars and mandibular second molars were all tilted to the FH planes(L1-FH?L5-FH?L6-FH?L7-FH).There was a no evident difference among control group and malocclusion group(P<0.05).4.The relationship between the plane inclination and the position of the mandible was found to be a significant negative correlation(P<0.05)and the y-axis angle to the(SNB,NP-FH),which represent the forward and backward position of the lower jaw.There was a significant positive correlation between the mandibular plane angle(FH-MP)and the mandibular advancement(RP-FH)(P<0.05).5.The relationship between the inclination of the osseous II type high angle dislocation and the tooth position: the anterior plane tilt(OPA-FH)and the uppermiddle incisor lip inclination(U1-FH),the maxillary second premolar alveolar height(U5 '-PPmm),and the anterior plane inclination(OPA-FH)and the upper middle incisor lip inclination(U1-FH),the alveolar height of the maxillary second premolar.The alveolar height(U6'-PPmm),the maxillary first molar inclination(U6-FH),the maxillary second molar alveolar height(U6'-PPmm)and the maxillary second molar inclination(U6-FH)were significantly negatively correlated(p < 0.05)in the maxillary first molar,the maxillary first molar inclination(U6-FH),the maxillary second molar alveolar height(U7 '-PPmm)and the maxillary second molar inclination(U7-FH)(P< 0.05).It was positively correlated with the alveolar height(U1-PPmm)of maxillary middle incisor and the inclination of maxillary second premolar(U5-FH).Posterior plane inclination(OPP-FH)and upper mU5-FHiddle incisor inclination(U1-FH),maxillary first premolar inclination(U5-FH),maxillary first molar alveolar height(U6'-PPmm),maxillary first molar inclination(U6-FH),and upper middle incisor inclination(U1-FH),maxillary first premolar inclination(U5-FH),maxillary first molar alveolar height(U6 '-PPmm),and maxillary first molar inclination(U6-FH).There was a significant negative correlation between the inclination of maxillary second molar(U7-FH)(P< 0.05)and the inclination of maxillary second molar(P< 0.05).There was a significant positive correlation between the alveolar height(U5'-PPmm)and the vertical height(U7'-PPmm)of the maxillary second premolar.Conclusions1.Compared with the normal group,the upper and lower jaw teeth of high-angle Class II malocclusion showed unique morphological characteristics,and the steepness of the anterior and posterior plane increased as the compensatory abnormality of the upper and lower jaw teeth.2.The anterior and posterior plane inclination of high-angle Class II malocclusion was correlated with the retraction and posterior rotation of the mandible.3.The anterior and posterior obliquity of high-angle Class II malocclusionwere correlated with the vertical height of the teeth and the angle of the tooth inclination.4.On the basis of conclusion 3,It is suggested that the vertical control of high-angle Class II malocclusion can be achieved by changing the vertical height and inclination of the teeth.