Clinical Study On Orthodontic Treatments For Complete Unilateral Cleft Lip And Palate Patients In Late Permanent Dentition

Objective:For the cleft lip and palate post-surgery characteristics of complete Unilateral Cleft Lip and Palate(UCLP) patients'teeth,occlusion, soft and hard tissues in late permanent dentition, the purpose of this study was to investigate the clinical effects of orthodontic treatments including slow maxillary arch expansion and fixed appliance for these kinds of patients on face types, narrow maxillary dental arch and occlusion relations with measuring related data which include X-ray lateral skull films before therapy, after six months maxillary expansion maintaining and teeth models of pre-expansion, post-expansion and after six months maintaining and to provide the reliable theoretic basis for orthodontic treatments for the cleft lip and palate post-surgery complete UCLP patients in late permanent dentition.Materials and Methods:Ten complete UCLP patients who are cleft lip and palate post-surgery in late permanent dentition(From 15 to 17 years old) were included in this research. Every patient was treated by orthodontic treatments including slow maxillary expansion with expansion screws'removable appliance and fixed appliance. The related data about X-ray lateral skull films before therapy and after six months maxillary expansion maintaining, the arch width, alveolar arch width and arch width of the base bone in teeth models of pre-therapy, post-expansion and after six months maintaining were measured. The results were compared with SPSS 18.0 statistical software. The Statistics Methods are paired t-test for dependent samples and two-way ANOVA, LSD-test is used for the mutual comparison between two groups.Results:After orthodontic treatments, some measured data of soft and hard tissues in complete UCLP patients'lateral skull films and arch width in study model have relatively significant changes.1. Hard tissues:the maxillary position to skull and its relative protrusion were improved significantly, the angle of SNA was increased, the angle of ANB was reduced, the angle of NA-PgA and the Wits value were reduced significantly;2. Soft tissues:Concave-type facial profile was improved significantly, convexity degree of upper lip was increased and more plump, the eversion phenomenon of lower lip was improved, the angles of SN'Sn, N'-Sn-Pos, A'UL-FH and UL-N'-Pos were increased significantly, the distance of UL-E was increased significantly; the angles of SN'B', B'LL-FH, LL-N'-Pos and the distance of LL-E were reduced;3. Axial inclined degree of anterior teeth:upper anterior teeth leaned to the lip and lower anterior teeth leaned to the tongue, the angles of Ul-SN, Ul-NA and the distance of Ul-NA were increased significantly, the distance of Ll-NB was reduced; 4. Arch width:after slow maxillary arch expansion, the data of interdental width and the distance between tongue tips in the first premolar 4-4,4'-4',interdental width in the second premolar 5-5 from three samples in study models of UCLP patients in late permanent dentition changed. The changes during pre-therapy, post-expansion and after six months maintaining and the effect of maintaining had statistical meaning, the data of interdental width in the first molar 6-6 from three samples had no statistical meaning, the data of interdental width in maxillary canine 3-3 had a change with statistical meaning after maxillary arch expansion, but had no statistical meaning after six months maintaining. Arch width increased significantly in canine area and premolar area after orthodontic treatments, the effect of maxillary arch expansion in premolar area was ralatively stable. However, the data in alveolar arch width and arch width of the base bone had no statistical changes.Conclusion:After orthodontic treatments, the bone, soft and hard tissues and occlusion relations of complete UCLP patients who are cleft lip and palate post-surgery in late permanent dentition have relatively ideal effects. After slow maxillary arch expansion and fixed appliance, the sagital plane of maxillary skull moved forward, the arch width of maxillary was increased, the mandible had no significant change, occlusion relations were improved, simultaneously, facial profile of patients'soft tissues were improved significantly, which showed the change of facial profile from concave-type to straight-type, convexity degree of upper lip was increased and more plump, the eversion phenomenon of lower lip was improved, the maxillary and mandible were more coordinated.