Severe Gummy Smile with Class II Malocclusion Treated with LeFort I Osteotomy Combined with Horseshoe Osteotomy and Intraoral Vertical Ramus

Transcription

1 Severe Gummy Smile with Clss II Mlocclusion Treted with LeFort I Osteotomy Comined with Horseshoe Osteotomy nd Introrl Verticl Rmus Osteotomy *

2 56 Shimo et l. Act Med. Okym Vol. 67, No. 1 impction cses [9, 10]. However, there re few reports out cses of severe gummy smile. In this report, we present the cse of severe gummy smile with clss II mlocclusion treted with LeFort I osteotomy comined with horseshoe osteotomy, introrl rmus osteotomy (IVRO), nd genioplsty. Cse Report A 34-yer-old womn with clss II mlocclusion cme to our deprtment complining of gummy smile. Her pst medicl history ws insignificnt, including lck of fmily history of mlformtion. In the extrorl exmintion, severe dolichofcil condition with retrognthi ws oserved. The upper gingiv ws exposed out 11mm from the cervicl line to the Fig. 1 upper lip while smiling (Fig. 1). Introrl exmintion reveled clss II mlocclusion with n excessive positive overite (3mm) nd overjet (6mm). Representtive preopertive cephlometric vlues were s follows: SNA, 82.7 ( 1.1 SD); SNB, 87 ( 0.3 SD); ANB, 8.5 ( 2.2 SD); A to N perpendiculr to FH 0.8 ( 1.5 SD); pogonion to N perpendiculr to FH, 24.5mm ( 1.0 SD); mx1 Crown to FN, 70.5mm; mx6 Crown to FH, 59mm; Mndiulr Plne, 42.4 deg ( 3.1 SD); Pos Fce Height (S-Go), 86.8mm ( 0.5 SD); Ant. Fce Height (N-Me), 147.6mm ( 2.3 SD); S-Go/N-Me, 58.8ｵ ( 0.5 SD); Ricketʼs VERT index, 8.8 (Fig. 1 nd Tle 1). The ptient ws dignosed s hving n ngle clss II mlocclusion with skeletl clss II jw se reltionship nd severe gummy smile. The tretment Pretretment extrorl nd introrl views.

3 Ferury 2013 Horseshoe Osteotomy for Severe Gummy Smile ojectives were to chieve cceptle occlusion, estlish n idel overjet nd overite, nd correct the gummy smile nd retrognthic fcil ppernce. First, we mesured the thickness of the one from the nterior nsl floor to the picl root of the first incisor, nd confirmed the re for removl using Osirix imging softwre dedicted to DICOM imges generted y CT (dt not shown). Next, 3D tretment plnning model ws mde y using Z Printer 310 plus (Z Corportion, Portsmouth, NH, USA) fter DICOM dt hd een otined from the ptient Tle 1 Cephlometric nlysis of cse Preopertive A to N - FH pogonion to N - FH mx1 Crown to FH mx6 Crown to FH Mndiulr Plne Post. Fce Height (S-Go) Ant. Fce Height (N-Me) S-Go / N-Me Postsurgicl 0.8 mm 24.5 mm 1.9 mm 10.5 mm 70.5 mm 59 mm 42.4 deg 86.8 mm mm 58.8% 62.5 mm 54 mm 37.9 deg 87.7 mm mm 60.1% 57 y use of Mimics Softwre (Mterilise, Lueven, Belgium). The surgicl incisions were mrked on the 3D model. (Fig. 2A nd C). A mxillry LeFort I osteotomy comined with horseshoe osteotomy (mx1 impction, 8mm; mx6 impction, 5mm; Fig. 2B), mndiulr ilterl introrl verticl rmus osteotomy (IVRO, trnsferred quntity ws offset), nd genioplsty (6-mm dvncement) were performed. The LeFort I osteotomy ws done y following the technique of Bell [8]. After ccomplishing LeFort I osteotomy nd down frcture, horseshoe osteotomy ws performed from the superior surfce of the downfrctured mxill. Using reciprocting sw, n osteotomy ws performed from the superior surfce of the down-frctured mxill through the nterior nsl floor nd the mxillry sinus into the orl cvity (Fig. 2D, dotted line). The sw ws used crefully to cut from the lterl side of the plte directed medilly to void injury to the dentl roots. After tht, the downfrctured mxill ws seprted into 2 prts,, dentolveolr nd pltl comprtments. Rigid osteosynthesis for the mxillry osteotomy ws provided using L-shped titnium minipltes. Mndiulr ilt- A B C D Fig. 2 Surgicl simultion nd opertion view of LeFort I osteotomy comined with horseshoe osteotomy. Frontl (A nd B) nd superior (C nd D) view of sustntil 3D model nd opertion. Removl depth of the one mxill t the incisor (, 8 mm) nd the first molr (, 5 mm) is shown. The dotted line (C) nd rrowheds (D) represent the horseshoe osteotomy with the pltl component. The rrows indicte the point of the pltine vessel.

4 ʼ A B C D 3 A B C ʼ 1 ʼ 6 ʼʼ D E 12 3 ʼ E ʼ

5 Ferury 2013 Horseshoe Osteotomy for Severe Gummy Smile Fig Extrorl nd introrl views t 3 yers fter surgicl tretment. the risk of injury to the pltl mucos, nd lso mintin the nturl form of the nsl cvity fter nterior superior impction of the mxill. This surgicl procedure my e one pplicle method for ptients with severe gummy smile. For mndiulr orthognthic surgery, IVRO is minly used to set ck the mndile [14] nd is not suitle for mndiulr dvncement, ecuse it is difficult to chieve n dequte one contct re etween the proximl nd distl segment fter mndiulr dvncement. In ddition, IVRO hs een used for ptients with symptoms of temporomndiulr disorder (TMD) [15]. In this ptient, IVRO ws performed ecuse the ptient hd TMD, nd the dvnce trnsferred quntity ws offset y the rottion of the mndile fter mxillry impction y the LeFort I osteotomy comined with the horseshoe osteotomy. In conclusion, this rticle reports the successful surgicl-orthodontic tretment of ptient with severe gummy smile nd clss II mlocclusion. Our results suggest tht the comintion of horseshoe osteotomy with LeFort I osteotomy is useful technique for relile superior repositioning of the mxill for tretment of ptients with severe gummy smile. Acknowledgments. The uthors thnk Dr. Mitsuhiro Hoshijim nd Tkshi Ymshiro for performing the orthodontic tretment fter surgery.

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