Orthodontic-Orthognathic Surgery Of Adult Skeletal Class Ⅲ Malocclusion And Jaw Asymmetry Deformity With Impacted Maxillary Canine

Objective: To explore the effects of clinical treatment on soft tissue appearance through the case of an adult skeletal Class Ⅲ malocclusion and jaw asymmetry deformity with impacted maxillary canine patient,who has been treated by the orthodonticorthognathic surgery.Methods: A 22-year-old female patient skeletal Class Ⅲ malocclusion and jaw asymmetry deformity with impacted maxillary canine was selected from the stomatology clinic of the Second Affiliated Hospital of DaLian Medical University in September 2015.The patient described that she found out that her face is asymmetrical when she was at the junior middle school stage,and the malocclusion grew worse gradually.She had oral habits of asymmetrical chewing and mouth breathing.We made the diagnosis and treatment plan by checking up the patient with buccal examination,functional examination,model analysis,cephalometric analysis and facial analysis.The patient is in permanent dentition,with a molar and canine Class III relationship on the right side and a molar Class Ⅱ relationship on the left side.There are III degrees of crowding in the upper arch with a left maxillary impacted canine,and I degree of crowding in the lower arch.Median line of the upper jaw is 2 mm to the right,while the lower one is 6 mm to the left.The anterior and left posterior teeth are with crossbite.The compensation of the upper and lower incisors are obvious.The patient’s face is asymmetrical,the deflective chin is on the left obviously;there is no click and pain in the temporomandibular joint;the lower jaw towards the left the whole time during opening mouth.and the asymmetry rate of the upper and lower jaws is high,therefore the patient is diagnosed as skeletal Class III malocclusion and jaw asymmetry deformity and receives the treatment named orthodontic-orthognathic surgery.The treatment plan is to extract the 14,24 and to use straight wire fixed appliance.Then orthodontic-orthognathic surgery helps the impacted canine to erupt after that the other teeth are arranged in a correct order.Set up normal overbite and overjet by extraoral occlusal model simulation.Only when there is no obvious interference in the dental arches,the orthognathic surgery(Le Fort I maxillary osteotomy and sagittal split ramus osteotomy BSSO and genioplasty)can be carried out.Postoperative orthodontic is a process of traction and adjustment of individual teeth,which maintains a stable relationship of dental arches and jaws.We made a comprehensive analysis of the treatment effects by comparing the cross-referencing data of orthodontic-orthognathic surgery.Results: The orthodontic-orthognathic surgery lasted for 22 months in total.The results after treatment are as follows.(1)Oral condition: Teeth are arranged in correct order,inclination and position in the dental arches.A molar and canine complete Class II relationship has achieved bilaterally.The upper and lower dental arches are symmetrical,the widths of which are in normal range.Median lines of the upper and lower jaw are the same.The anterior and posterior teeth are with normal overbite and overjet.The left maxillary impacted canine is in the normal position,and there is no obvious gingival atrophy.(2)Soft tissue appearance: The face is basically symmetrical.The line connected pupils is basically parallel with that connected the corners of mouth.The mandibular protrusion is corrected.The angle of chin and lip become smaller,and the facial profile is straight.(3)X-ray film:(1)Panoramic radiograph: The upper and lower mandibular roots of teeth are relatively parallel.There are no evident roots and alveolar bone resorption.(2)Lateral film: SNA increased by 3.23° and SNB decreased 0.27°,which reflect that the relationship between maxillary and mandible’s position and the base of the skull is improved.ANB increased by 3.54°,Wits increased by 6.28,AB-NP decreased by 4.81° and APDI decreased by 6.69°,which reflect that the asymmetry deformity of upper and lower jaws is improved.U1-NA decreased by 8.27°,U1-SN decreased by 3.71°and L1-NB increased by 4.64°,indicating that the compensation of the upper and lower incisors are removed.Total Chin/Upper Lip changed to 1 and Z angle increased by 12.32°,indicating that the soft tissue of the upper and lower jaw is rebuilt,the distribution is uniform and the facial profile is obviously improved.(3)Frontal film: The occlusal plane of upper and lower jaw is obviously improved,the mandibular asymmetry rate is significantly reduced,and the oblique chin is corrected.(4)Functional examination: The temporomandibular joint has neither clicking nor pressing pain,and there is no abnormal opening degree and pattern.Occlusal interference is removed.The patient is very satisfied with the improvement of appearance and the oral system.Conclusion: Adult skeletal Class Ⅲ malocclusion with jaw asymmetry deformity is a kind of complex case,which has multiple pathogenesis and complicated clinical manifestation.Therefore,no matter orthodontic treatment or orthognathic surgery cannot achieve perfect result of treatment individually.As for the skeletal Class Ⅲ malocclusion patients with impacted maxillary canine which caused by maxillary deficiency,it is more necessary to adopt pre-surgical orthodontic treatment and orthognathic surgery combined with gingival flap operation,so as to reach the target that preserve the whole dentition and make the facial profile fine and harmonious.Orthodontic-orthognathic surgery has a significant improvement on the function and appearance of the maxillofacial system,it also has a positive effect on the temporomandibular joint.What’s more,a stable and coordinating occlusal pattern is built after this kind of treatment.