The Orthodontic Treatment In An Adult Patient With Bimaxillary Protrusion

Objective: The purpose of this paper is to discuss the effect of high pull J hook headgear and transpalate arch as anchorage applied in adult patient with bimaxillaryprotrusionMethod: A female patient was selected from Dorcto dental clinic in August2010.Thispatient was22years old used to had some bad oral habits,with permanentdentition,normal maxillary and protrusive mandibular.Molar and canine relationship areboth class in two sides.There exits slight crowding in both arch,and the medlines arein the middle.The overjet and overbite in anterior are normal.Curve of spee arenormal,the profile was convex.So this case was an extraction case and we chose toremove four first premolars and four third molars.According to the examination of thispatient,we decided to use straight archwire technique and self-ligation brackets,withhigh pull head gear and transpalate arch as anchorage.Alignment and leveling maxillaryand mandibular dentition,and canine retraction was completed with J-hook and powerchain till canine got class relationship.And high pull head gear was used to retracteanteriors to finish space closure.Classē elastic was applied in this patient to correct theocclusal relationship in finishing stage.Finally,we compare and analysis thecephalometrics of pretreatment and postreatment.Result: the treatment course lasted for33months.Both dentitions were well alignment and leveling,space of extraction was completely closed.Medlines are in themiddle,overjet was2mm and overbite was normal,relathionship of molars and caninesare both class in two sides.By comparing the panoramic X-ray,there were no obviousresorption in the root area.Cephalometrics comparision showed:(1)there were noobvious change in maxillary and mandibular bone,the occlusal plane did notrotate.SNA,SNB did not change too much,SNA decreased1°,SNB kept the samevalue,ANB decreased1°;(2)axis of upper anterior U1-SN decreased from115to108,axis of lower anterior L1-MP decreased from104to91,L1-NB decreased from42to30;(3)nasalabial angle Cm-Sn-Ls increased4,ULP decreased from10mm to7mm,LLP decreased from12mm to9mm,upper lip angle A UL-FH increased6,thatindicated upper lip protrusion was corrected,lower lip angle B UL-FH increased7,thatindicated lower lip retraced in some degree,UL-EP decreased from6mm to3mm,LL-EPdereased from9mm to5mm,that indicated both protrusive upper and lower lips werewell corrected,Z-angle increased from56to65,H-angle decreased from21to19,therelationship between chin and lips were well coordinated.Soft tissue angleFH-Ns-Pg did not change too much,that demonstrated pure orthodontic could notchange the alveolar bone obviously.So for those who wanted to correct profileperfectly,might seek help from surgery.Conclusion:High pull head gear associated with transpalate arch,as maxiumanchorage,can effectively control the position of molars in vertical and sagitaldemonsion in adult patient with bimaxillary protrusion,ensure the space was completelyused to retracted anteriors and correct the protrusive profile obviously.