ORIGINAL ARTICLE 황현식 a ㆍ Jessica J. Lee b ㆍ황정현 c ㆍ최학희 d ㆍ임회정 e 본연구는안면비대칭환자의악교정수술시경조직이동에따른연조직변화를정면에서평가함으로써정면얼굴이미지시뮬레이션프로그램개발에도움이되고자시행되었다. 안면비대칭이동반된하악골수술예정환자 45 명을대상으로정모두부방사선규격사진과얼굴사진 (photo) 을술전및술후에각각같은각도로촬영한후, 술전및술후의방사선사진을이용하여경조직계측점의변화를, 얼굴사진을이용하여연조직계측점의변화를수평및수직으로구분하여각각측정한후경조직변화에따른연조직변화를비교분석하였다. 연조직변화와경조직변화의상관성을살펴본결과수평방향, 수직방향모두에서전반적으로낮은상관성을보였으며, 1:1 mean ratio 산출을위하여서로상관성이가장높은경조직계측점을연조직계측점별로선택한결과직하방에있는경조직보다는다소멀리떨어져있는경조직계측점이선택되는경우가많이나타났다. 경조직변화를이용하여연조직변화를예측할수있는회귀방정식을연조직계측점별로산출한결과연조직수평변화예측에경조직수직변화도사용되고연조직수직변화예측에경조직수평변화도사용되었으며, 수평과수직변화모두에서가장설명력이높은방정식은연조직 menton 에서나타났다. 이상의연구결과하부경조직계측점과상부연조직계측점의비율을이용하는 1:1 mean ratio 방법은불가능한것으로나타난반면회귀분석을이용한연조직변화예측은임상에도움이될수있는것으로나타나정면이미지의경우컴퓨터를이용한시뮬레이션프로그램이반드시필요함을시사하였다. ( 대치교정지 2008; 38(4):252-264) 주요단어 : 연조직변화예측, 정모두부방사선사진, 정면얼굴사진, 안면비대칭, 이미지시뮬레이션 서론 악교정수술환자의치료계획수립시경조직을기준으로수술의양과방향을결정하는반면수술결과에대한만족도는연조직변화에의해좌우된다. 이러한이유로경조직이동에대한연조직반응에 a 교수, 전남대학교치의학연구소, 2단계 BK21 연구사업단, 치과대학교정학교실. b 조교수, 워싱턴대학교구강악안면외과학교실. c 연구원, 한국성인교합연구소. d 대학원생, e 조교수, 전남대학교치과대학교정학교실. 교신저자 : 황현식. 광주시동구학동 8 번지전남대학교치과대학교정학교실. 062-220-5486; e-mail, hhwang@chonnam.ac.kr. 원고접수일 : 2007 년 5 월 4 일 / 원고최종수정일 : 2007 년 11 월 2 일 / 원고채택일 : 2007 년 11 월 5 일. * 본논문은전남대학교병원학술연구비 (CUHRICM-U-200652) 에의하여연구되었음. 관한많은연구가있어왔으며 1-8 또한이를예측하는것에대한시도가있어왔다. 9-14 McNeill 등 9 은아세테이트투사지를잘라붙이는방법을이용하여수술에의한경조직이동에따른연조직측모의변화를예측하고자하였고, Kinnebrew 등 10 은슬라이드를투사하여경조직과연조직을합성하고연조직변화를포함한치료계획수립방법을제안하였다. 이후컴퓨터테크놀로지의발달과함께 Bhatia 와 Sowray, 11 Harradine 과 Birnie, 12 Sarver 등 13, Sarver 와 Johnston 14 은환자의두부방사선사진과얼굴사진 (photo) 을컴퓨터로합성하고수술후얼굴사진의변화를컴퓨터프로그램으로예측하는방법을보고하였으며실제로이를임상에서적용할수있는프로그램이다수개발되어현재활발하게사용되고있다. 컴퓨터를이용한연조직변화예측그리고이를얼굴사진의변화로나타내는영상시뮬레이션방법 252
Vol. 38, No. 4, 2008. Korean J Orthod 의개발로이는교정과의사와외과의사등전문가간의사소통은말할것은없고술자와환자간의의견교환및치료계획수립및결정에큰도움이되고있다. 그러나현재까지의모든연구는측면이미지에제한되었으며정면이미지를대상으로시행한연구는전무한실정이다. 최근사회경제적여건의향상과함께심미에대한관심이증가하면서약간의비대칭도민감하게반응하는현실을고려할때정면에서의연조직변화및이를예측하는이미지시뮬레이션에대한연구가필요한반면이에대한연구는부진한상태였다. 경조직변화에대한연조직변화의연구를위해서는두부방사선사진과얼굴사진의합성이선결되어야하는데측면이미지의경우이의합성이큰문제가없는반면, 정면이미지의경우이의합성에애로가있었다. 각각의영상촬영시두부의측방회전은 ear rod 에의해고정되는반면수직회전은자유로이허용되는두부방사선사진특성상정면방사선사진과정면얼굴사진의합성은불가한것으로받아들여져왔다. 그러나최근 Hwang 등 15 은일정한두부자세에서방사선사진을촬영할수있는두부자세재현기 16 를고안하고이를적용하는방법을발표하여일정한두부자세에서측모및정모두부방사선사진그리고측면및정면얼굴사진을찍을수있는가능성을제시하였다. 본연구는수술전및수술후에각각두부자세재현기를이용하여같은두부자세에서정모두부방사선사진과정면얼굴사진을채득한후방사선사진상의경조직변화와얼굴사진상의연조직변화의상관성을살펴보는한편다중회귀분석으로연조직변화를예측하는방정식을구함으로써컴퓨터를이용한정면얼굴이미지시뮬레이션에도움이되고자시행되었다. 연구방법 연구대상 안면비대칭을동반한악교정수술예정환자 45 명을나이, 성별에관계없이본연구의대상으로선정하였다. 본연구에서는시상골절단술에의한하악골수술환자로제한하였으며하악골후퇴증으로인한수술환자는제외하였다 (Table 1). 연구방법 정모두부방사선규격사진및정면얼굴사진촬영술전교정이종료된상태에서그리고악교정수술후 1 개월째정모두부방사선규격사진및정면얼굴사진을촬영하였는데동공의위치가정모두부방사선사진에나타날수있도록 Kim 등 17 의방법에따라동공위치지시기 (Pupil Position Marker) 를, 그리고정모두부방사선사진과정면얼굴사진촬영시같은두부자세에서영상을채득할수있도록 Kim 과 Hwang 16 의방법에따라두부자세재현기 (Head Posture Aligner) 를사용하였다. 먼저물방울수평계 (Precision Torpedo Level, Johnson Level & Tool Manufacturing Co, USA) 가부착된두부자세재현기를연구대상자의얼굴좌측면에부착한후거울앞 1.5 m 지점에서서거울속의눈동자를보도록지시한후물방울수평계를 0 으로조정하여두부자세를입력하였다. 두부방사선규격사진촬영기 (PM2002 CC Proline, Planmeca, Finland) 의두부고정대에대상자를위치시키고좌우측외이도에 ear rod 를위치시켜두부의수평회전을고정하는한편두부자세재현기내의물방울수평계가 0 이되도록두부의수직회전정도를조정하였다. 아울러동공위치지시기내의좌우동공표시점을대상자의동공과맞도록조정한후방사선원과 ear rod 축간거리 150 cm, ear rod 축과필름간거리 15 cm, 10 ma, 75-85 KVp, 노출시간은 1.6 초의조건으로정모두부방사선규격사진을촬영하였다. 한편차후방사선사진에나온불투과상을이용하여기준선작성에사용하기위하여 Hwang 등 18 의방법에따라대상자의귀에삽입되는좌우 ear rod 의끝에 metal ball marker 를부착한후촬영하였다. 정모두부방사선규격사진을촬영한후에는, 방사선사진조사부를제거하고 100 mm macrolens 와함께치과전용카메라 (Dental Eye III, Yashica, Japan) 를장착한두부방사선규격사진촬영장치의두부고정대에연구대상자를위치시키고, 방사선사진촬영시와마찬가지로좌우측외이도에 ear rod 를위치시켜두부의수평회전을고정하는한편두부자세재현기내의물방울수평계가 0 이되도록대상자의두부의수직회전정도를조정한후정면얼굴사진을촬영하였다. 방사선사진과얼굴사진촬영시모두에서, 두부의수직회전정도는두부자세재현기에의해얻어진자세를택하는반면, 치아는중심교합위 253
황현식, Jessica J. Lee, 황정현, 최학희, 임회정 대치교정지 38 권 4 호, 2008 년 Table 1. Description of the subjects used in this study and summary of orthognathic surgery performed Subject Sex Age Chin deviation Year-Month Surgery * Before After KSM F 21-0 Mn, 8.0 setback; Genio, Vt 3.0 reduction; Zygoma, Rt 4.0 Lt 3.0 augmentation Rt 2.0 Rt 1.5 KSG F 22-4 Mn, Rt 8.0 Lt 3.0 setback; Both angle reduction Lt angle corticotomy Lt 5.0 0 KIH F 21-1 Mn, 10.0 setback; Genio, AP 3.0 reduction Lt 5.0 Lt 4.0 KYS M 23-6 Mn, Rt 6.0 Lt 2.0 setback; Both angle contouring Lt 4.0 Lt 1.0 KWS M 25-9 Mn, Rt 6.5 Lt 5.0 setback Lt 5.0 Lt 3.5 KKY F 21-10 Mn, Rt 9.0 Lt 6.0 setback; Genio, Vt 3.0 reduction AP 3.0 reduction Lt 2.0 0 KDH M 27-0 Mn, Rt 11.5 Lt 8.5 setback; Paranasal augmentation Lt 3.0 Lt 1.5 KMK F 21-10 Mn, Rt 6.5 Lt 7.5 setback Rt 2.0 Rt 0.5 KMJ F 20-10 Mn, Rt 6.5 Lt 10.5 setback; Genio, Vt 3.0 reduction Rt 7.0 0 KBJ M 25-10 Mn, Rt 8.0 Lt 12.0 setback; Genio, AP 3.0 advancement; Rt 2.0 Rt 1.0 Both angle contouring KBW M 27-3 Mn, Rt 13.0 Lt 17.0 setback; Genio, Vt 4.0 reduction Rt 5.0 0 KYS F 18-8 Mn, Rt 7.0 Lt 6.0 setback; Genio, Vt 3.0 reduction Rt 1.5 0 KYL F 22-6 Mn, Rt 15.5 Lt 13.5 setback; Genio, Vt 3.0 reduction Lt 3.5 0 KJH M 34-0 Mn, Rt 2.0 Lt 13.0 setback Rt 11.0 0 KCW M 23-5 Mn, 14.5 setback; Genio, Vt 6.0 reduction Lt 0.5 Lt 0.5 KPM M 25-3 Mn, Rt 5.0 Lt 12.0 setback Rt 6.0 Rt 1.0 KHC M 35-1 Mn, Rt 15.5 Lt 4.5 setback; Genio, AP 3.0 reduction Lt 6.0 Rt 1.0 NHG M 26-4 Mn, Rt 4.0 setback Lt 5.0 0 PSA F 26-6 Mn, Rt 9.0 Lt 6.0 setback; Genio, Vt 3.0 reduction; Lt 2.0 0 Both angle contouring PJS M 26-3 Mn, Rt 7.5 Lt 5.5 setback Lt 1.0 Rt 2.0 SHN F 24-7 Mn, Rt 4.0 Lt 9.5 setback; Both angle contouring Rt 6.0 Rt 1.5 SHS M 29-8 Mn, Rt 11.5 Lt 10.5 setback; Genio, Vt 5.0 AP 5.0 reduction Lt 1.0 0 SJS M 24-6 Mn, Rt 9.5 Lt 13.5 setback; Lt angle corticotomy Rt 1.5 0 YBH F 27-8 Mn, Rt 2.5 Lt 7.0 setback Lt 5.0 Lt 2.0 SKC M 24-9 Mn, Rt 10.5 Lt 8.0 setback; Genio, Vt 4.0 reduction Lt 2.0 0 YHJ F 19-4 Mn, Rt 7.0 Lt 10.0 setback Rt 3.5 0 LGH M 24-3 Mn, Rt 1.0 Lt 6.0 setback; Lt angle augmentation Rt 8.0 Rt 3.0 LGH M 26-11 Mn, Rt 6.5 Lt 7.5 setback; Genio, Vt 6.0 AP 4.0 advancement Lt 2.0 Lt 2.0 LNR F 18-5 Mn, Rt 11.5 Lt 11.0 setback; Genio, Vt 3.0 reduction Rt 1.5 Rt 1.5 254
Vol. 38, No. 4, 2008. Korean J Orthod Table 1. Continued Subject Sex Age Chin deviation Year-Month Surgery * Before After LSN F 18-10 Mn, Rt 4.5 Lt 12.5 setback Rt 6.0 Lt 1.0 LYH M 33-4 Mn, Rt 1.0 Lt 6.0 setback Rt 3.0 Lt 0.5 LJH F 28-10 Mn, Rt 8.5 Lt 8.0 setback; Genio, Vt 5.0 reduction Lt 0.5 Lt 0.5 LHJ M 24-1 Mn, Rt 5.0 Lt 12.0 setback; Genio, Vt 3.0 reduction Rt 4.0 Rt 1.5 JWS M 22-9 Mn, Rt 14.5 Lt 5.5 setback; Genio, Vt 5.0 reduction AP 5.0 advancement Lt 10.0 Lt 4.0 JGT M 23-6 Mn, Rt 8.5 Lt 5.5 setback; Both angle 5.0 reduction Lt 4.0 Lt 2.0 JMS M 28-0 Mn, Rt 6.0 Lt 7.0 setback Rt 2.0 Rt 1.0 JMY F 24-11 Mn, Rt 6.0 Lt 8.0 setback; Genio, AP 4.0 advancement; Both malar Lt 1.0 Rt 2.0 reduction JSK M 25-10 Mn, Rt 7.0 Lt 4.0 setback; Genio, Vt 3.0 reduction Lt 8.0 Lt 1.0 JSM F 28-0 Mn, Rt 10.0 Lt 5.0 setback Lt 3.5 Lt 0.5 JHJ F 21-10 Mn, Rt 7.5 Lt 3.0 setback Lt 7.0 Lt 2.0 CYR F 19-4 Mn, Rt 7.0 Lt 5.0 setback; Genio, Vt 3.0 reduction Lt 3.5 Lt 1.0 CCJ M 30-6 Mn, Rt 11.5 Lt 5.0 setback; Genio, Vt 5.0 reduction AP 3.0 advancement Lt 6.0 Lt 2.0 HYK F 26-6 Mn, Rt 7.0 Lt 3.0 setback; Genio, AP 4.0 reduction Lt 2.5 0 HSW M 25-6 Mn, Rt 8.0 Lt 2.0 setback; Genio, Vt 3.0 reduction Lt 8.0 Lt 1.0 HEA F 19-3 Mn, Rt 9.5 Lt 8.0 setback; Genio, Vt 5.0 reduction AP 3.0 advancement Rt 1.0 Rt 3.0 * The number in the surgery column indicates the amount of operation (unit; mm); The degree of chin deviation before and after surgery is expressed as the angle formed by Cg-ANS and ANS-Me lines (unit: o ). Mn, mandible; Genio, genioplasty; Vt, vertical; AP, anteroposterior; Rt, right; Lt, left. 로교합된상태로그리고입술은이완된상태에서자료를채득하였다. 투사도작성및계측점의변화량측정술전및수술후에촬영된정모두부방사선사진위에아세테이트지를부착하고 Fig 1, Table 2 와같은계측점을이용하여투사도를작성하였다. 방사선사진에투영된좌우 ear rod ball marker 를이용하여수평기준선을작도하고이에직각이면서 Cg 를지나는수선을수직기준선으로작도하였다. 얼굴사진의경우현상된슬라이드를스캐너를이용하여 JPEG 화일로저장한후이를 Image Analyzer (Image Pro Plus, Media Cybernetics, USA) 에입력하였다. 방사선사진상에나타난좌우동공점간거리와얼굴사진상의동공점위치를이용하여각각의확대율을고려한얼굴사진의 calibration 을시행한후 Fig 2, Table 3 과같은계측점을설정하고좌우동공점을연결한선을수평기준선으로그리고이의수직이등분선을수직기준선으로작도하였다. 술전및술후방사선사진투사도그리고술전및술후얼굴사진에서각각수평기준선을 X 축으로하고수직기준선을 Y 축으로하여각계측점들의술전위치에서술후위치로의수평및수직변화량을방향과함께표시하였다. 수평변화량은 Δh, 수직변화량은 Δv 로표시하였으며, 수평변화량의경우술후계측점이술전에비해비대칭이개선되는방향으로이동한경우를 (+) 로, 수직변화량의경우에는하방으로이동한경우를 (+) 로, 그반대방향인경우를각각 (-) 로표시하였다. 255
황현식, Jessica J. Lee, 황정현, 최학희, 임회정 대치교정지 38 권 4 호, 2008 년 통계처리 Fig 1. Cephalometric landmarks to represent hard tissue change. Detailed description of landmarks is in Table 2. 술전및술후투사도에서각경조직계측점의경조직수평변화량 (Δh), 수직변화량 (Δv) 을, 술전및술후얼굴사진에서연조직계측점의수평변화량 (Δ h), 수직변화량 (Δv) 을각각산출한후경조직계측점변화량과연조직계측점변화량간의상관관계를알아보기위하여수평변화량과수직변화량을구분하여 Pearson 상관분석을시행하였다. 연조직변화에가장영향을미치는경조직을연조직계측점별로찾고이들간의 1:1 평균변화율 (mean ratio) 을알아보기위하여각연조직계측점에서가장상관성이높은경조직계측점을선택한후경조직계측점의변화량에대한연조직계측점의변화량비율을수평과수직을구분하여산출하였다. 모든경조직점의변화를이용하여연조직변화를 Table 2. Description of frontal cephalometric landmarks used in this study Landmark Name Definition Cg Crista galli Mid point of crista galli ANS Anterior nasal spine Tip of anterior nasal spine J dev Jugal process (dev) Intersection of jugal process with maxillary tuberosity (deviated side) J ctl Jugal process (ctl) Intersection of jugal process with maxillary tuberosity (contralateral side) U6 dev Upper first molar (dev) Most buccal point on the crown of upper first molar (deviated side) U6 ctl Upper first molar (ctl) Most buccal point on the crown of upper first molar (contralateral side) L6 dev Lower first molar (dev) Most buccal point on the crown of lower first molar (deviated side) L6 ctl Lower first molar (ctl) Most buccal point on the crown of lower first molar (contralateral side) U1 Upper incisors Mid point between upper central incisors at the level of incisor edges L1 Lower incisors Mid point between lower central incisors at the level of incisor edges Ar dev Articulare (dev) Intersection of ascending ramus with the contour of mastoid process (deviated side) Ar ctl Articulare (ctl) Intersection of ascending ramus with the contour of mastoid process (contralateral side) Go dev Gonion (dev) The most lateral and inferior point at the angle of the mandible (deviated side) Go ctl Gonion (ctl) The most lateral and inferior point at the angle of the mandible (contralateral side) Ag dev Antegonion (dev) The deepest point in the antegonial notch (deviated side) Ag ctl Antegonion (ctl) The deepest point in the antegonial notch (contralateral side) Me Menton Point on inferior border of symphysis directly inferior to mental protuberance 256
Vol. 38, No. 4, 2008. Korean J Orthod 예측하기위하여각연조직계측점의변화량을종속변수로하고수평과수직변화량관계없이모든경조직계측점변화량을독립변수로한단계적다중회귀분석 (stepwise multiple regression analysis) 을시행하고이를이용하여연조직계측점별로수평방향과수직방향의회귀방정식을구하였다. 연구성적 Fig 2. Photometric landmarks to represent soft tissue change. Detailed description of landmarks is in Table 3. 술전, 술후경조직변화량과연조직변화량의상관관계를수평변화량과수직변화량을구분하여산출한결과 Table 4 와 5 의결과를얻었다. 수평변화량의경우연조직변화량과가장많은경우에서유의한상관성을보인경조직계측점은 L6 dev, Me, 그리고 L1 으로각각 5 개의연조직계측항목과유의성을보여이들계측점의변화가연조직수평변화량예측에유용하게이용될수있음을시사하였다. 한편 Ar ctl, Ar dev, Go ctl, Go dev, Ag ctl, Ag dev 은소수의연조직계측항목과유의한상관성을보였으며, L6 ctl 은어느항목과도유의한상관성을보이지않아수평 Table 3. Description of photometric landmarks used in this study Landmark Name Definition P dev Preaurale (dev) Intersection of cheek contour with ear lobe on the deviated side P ctl Preaurale (ctl) Intersection of cheek contour with ear lobe on the contralateral side Pn Pronasale The most prominent point on the nose Al dev Alare (dev) The most lateral point of the contour of nose (deviated side) Al ctl Alare (ctl) The most lateral point of the contour of nose (contralateral side) Sn Subnasale The most inferior point on the outline of the middle area of nose UL Upper lip The superior point of the vermilion border of the middle area of upper lip LL Lower lip The inferior point of the vermilion border of the middle area of lower lip Ch dev Cheilion (dev) The most lateral point of the vermilion border of the lip on the deviated side Ch ctl Cheilion (ctl) The most lateral point of the vermilion border of the lip on the contalateral side Go' dev Soft tissue gonion (dev) The most lateral and inferior point of the outline of the deviated cheek Go' ctl Soft tissue gonion (ctl) The most lateral and inferior point of the outline of the contalateral cheek GM dev GM (dev) The bulkiest point of lower mandibular outline between gonion and menton of the deviated side GM ctl GM (ctl) The bulkiest point of lower mandibular outline between gonion and menton of the contalateral side Me Soft tissue menton The most inferior point of the prominence of the chin in middle area 257
황현식, Jessica J. Lee, 황정현, 최학희, 임회정 대치교정지 38 권 4 호, 2008 년 Table 4. Correlation coefficient between hard tissue change and soft tissue change in the horizontal direction Δh P dev Δh P ctl Δh UL Δh LL Δh Ch dev Δh Ch ctl Δh Go' dev Δh Go' ctl Δh GM dev Δh GM ctl Δh Me' Δh L6 dev 0.199 0.155 0.145 0.641 0.293 0.253 0.368 * 0.131 0.491 0.468 0.658 Δh L6 ctl 0.113 0.043 0.214 0.193 0.269 0.145 0.090 0.064 0.112 0.279 0.278 Δh L1 0.272 0.118 0.003 0.776 0.337 * 0.271 0.299 0.183 0.466 0.491 0.809 Δh Ar dev 0.002 0.360 * -0.104 0.173 0.072 0.038 0.309 * 0.289 0.412 0.065 0.121 Δh Ar ctl -0.268 0.429 0.103 0.183 0.029 0.154-0.003 0.364 * 0.250-0.073 0.080 Δh Go dev -0.073 0.111 0.445-0.015-0.094-0.173 0.103 0.178 0.098-0.066-0.229 Δh Go ctl -0.037 0.024 0.375 * 0.035 0.020 0.128-0.069 0.209 0.060 0.227 0.050 Δh Ag dev 0.040 0.144 0.358 * 0.008-0.152 0.009 0.154 0.114 0.025-0.008-0.186 Δh Ag ctl -0.164 0.175 0.311 * 0.082 0.026 0.198-0.077 0.356 * 0.011 0.226 0.031 Δh Me 0.209 0.107 0.100 0.696 0.407 0.206 0.231 0.190 0.414 0.483 0.782 * p < 0.05; p < 0.01. Table 5. Correlation coefficient between hard tissue change and soft tissue change in the vertical direction Δv P dev Δv P ctl Δv UL Δv LL Δv Ch dev Δv Ch ctl Δv Go' dev Δv Go' ctl Δv GM dev Δv GM ctl Δv Me' Δv L6 dev 0.241 0.258 0.093 0.142 0.152-0.006 0.262 0.243 0.545 0.475 0.583 Δv L6 ctl 0.410 0.358 * 0.108 0.221 0.161 0.005 0.367 * 0.426 0.536 0.550 0.580 Δv L1 0.302 * 0.248 0.148 0.328 * 0.158 0.010 0.281 0.293 0.597 0.497 0.594 Δv Ar dev 0.037-0.050 0.010-0.062 0.171 0.095 0.036 0.019-0.074-0.070-0.085 Δv Ar ctl 0.024-0.007-0.127-0.120 0.021 0.022-0.095-0.011-0.233-0.142-0.179 Δv Go dev -0.143-0.129 0.019 0.208 0.196 0.062 0.123 0.027 0.188 0.102 0.103 Δv Go ctl 0.251 0.160 0.056 0.288 0.355 * 0.133 0.342 * 0.382 * 0.317 * 0.363 * 0.283 Δv Ag dev 0.179 0.140 0.152 0.231 0.292 0.081 0.241 0.206 0.412 0.345 * 0.243 Δv Ag ctl 0.460 0.456 0.037 0.131 0.211 0.039 0.467 0.510 0.407 0.543 0.289 Δv Me 0.125 0.038 0.108 0.237 0.011-0.008 0.248 0.212 0.648 0.580 0.729 * p < 0.05; p < 0.01. 방향의연조직변화예측에도움이되지않는계측점임을나타내었다 (Table 4). 수직변화량의경우경조직계측점중 L6 ctl, L1, Go ctl, Ag ctl 이 5-7 개의연조직계측항목과그리고 Me 와 L6 dev 이 3 개의연조직계측항목과각각유의한상관성을보여연조직수직변화량예측에유용하게사용될수있음을시사하였으며 Ar ctl, Ar dev, Go dev 은어느항목과도유의한상관성을보이지않아수직방향의연조직변화예측에도움이되지않 는계측점임을나타내었다. 서로인접하여위치하고있는 Go 과 Ag 을비교한결과 Go 보다 Ag 이편위측과반대측모두에서보다많은연조직계측항목과유의한상관성을보이는것으로나타났다. L6 의경우편위측과반대측이서로다른양상을나타내었는데수평변화의경우에는편위측인 L6 dev 이많은연조직계측점과상관성을보인반면, 수직변화에서는반대측인 L6 ctl 이편위측 L6 dev 보다많은연조직계측항목과유의한상관성을보였다. 전반적으 258
Vol. 38, No. 4, 2008. Korean J Orthod 로수평변화에서는편위측경조직계측점이반대측계측점과같거나약간더많은상관성을보인반면수직변화에서는반대측계측점이편위측보다보다많은상관성을보여수평변화와수직변화는서로다른양상을나타내었다 (Table 5). 연조직계측점별로가장상관성이높은경조직계측점을선택하여 1:1 mean ratio 를산출한결과 Table 6 과 7 의결과를얻었다. 수평변화에서가장 상관성이높은경조직계측점을연조직계측점별로각각선택한결과 LL 한항목에서만바로하방에있는경조직이선택된반면나머지연조직은다른부위의경조직변화와짝을이루어 1:1 mean ratio 산출의미가희석되는양상을보였다. 한편 L1 은 5 개의연조직계측항목과짝을이루어수평방향의연조직변화예측에가장유용하게사용될수있는경조직계측점임을보여주었다. 바로하방의경조 Table 6. Mean ratio between soft tissue and hard tissue change in the horizontal direction Mean change (mm) Mean ratio Correlation Δh P dev / Δh L1 0.405 / 3.221 0.126 0.272 Δh P ctl / Δh Ar ctl 0.191 / 0.093 2.054 0.429 Δh UL / Δh Go dev 0.422 / 1.802 0.234 0.445 Δh LL / Δh L1 1.869 / 3.221 0.580 0.776 Δh Ch dev / Δh Me 0.767 / 4.023 0.191 0.407 Δh Ch ctl / Δh L1 1.586 / 3.221 0.492 0.271 Δh Go dev / Δh L6 dev 1.077 / 2.209 0.488 0.368 * Δh Go ctl / Δh Ar ctl 1.519 / 0.093 16.333 0.364 * Δh GM dev / Δh L6 dev 2.871 / 2.209 1.300 0.491 Δh GM ctl / Δh L1 3.282 / 3.221 1.019 0.491 Δh Me / Δh L1 4.561 / 3.221 1.416 0.809 * p < 0.05; p < 0.01. Table 7. Mean ratio between soft tissue and hard tissue change in the vertical direction Mean change (mm) Mean ratio Correlation Δv P dev / Δv Ag ctl 1.578 / 0.744 2.121 0.460 Δv P ctl / Δv Ag ctl 1.115 / 0.744 1.499 0.456 Δv UL / Δv Ag dev 0.021 / 0.826 0.025 0.152 Δv LL / Δv L1 0.232 / -2.477-0.094 0.328 * Δv Ch dev / Δv Go ctl 0.659 / 0.081 8.136 0.355 * Δv Ch ctl / Δv Go ctl -0.013 / 0.081-0.160 0.133 Δv Go' dev / Δv Ag ctl 0.009 / 0.744 0.012 0.467 Δv Go' ctl / Δv Ag ctl -0.196 / 0.744-0.263 0.510 Δv GM dev / Δv Me -1.380 / -3.279 0.421 0.648 Δv GM ctl / Δv Me -2.406 / -3.279 0.734 0.580 Δv Me' / Δv Me -2.106 / -3.279 0.642 0.729 * p < 0.05; p < 0.01. 259
황현식, Jessica J. Lee, 황정현, 최학희, 임회정 대치교정지 38 권 4 호, 2008 년 직인 L1 과짝을이룬 LL 의경우 mean ratio 는 0.580 으로나타나경조직의수평변화에대하여하순부위연조직은 58% 정도만따라가는양상을보여주었다 (Table 6). 수직적변화의경우에도 LL 과 Me' 두항목만바로하방의경조직계측점과짝을이루고나머지는직하방이아닌다른부위의경조직계측점과짝을이루어 1:1 mean ratio 의사용이유용하지않음을 시사하였다. 수직변화의경우 Me이 GM ctl, GM dev, Me' 등 3개의연조직계측항목과짝을이루는데사용되어연조직수직변화예측에유용하게사용될수있는계측점임을보여주었다. Me' 의경우하부경조직계측점의이동량에따른상부연조직계측점의변화를나타내는 mean ratio값이 0.642를보여경조직의수직적변화에대하여연조직은 64% 정도만따라가는양상을보여주었다 (Table 7). Table 8. Results of stepwise multiple regression analysis for the horizontal change of soft tissue points Equation R 2 Δh P dev - - Δh P ctl 0.71ㆍΔhAr ctl + 0.13 0.184 Δh UL 0.16ㆍΔhGo dev + 0.12ㆍΔhGo ctl + 0.11ㆍΔvAr ctl - 0.03 0.437 Δh LL 0.65ㆍΔhL1-0.22 0.602 Δh Ch dev 0.23ㆍΔhMe - 0.16 0.166 Δh Ch ctl - - Δh Go' dev 0.54ㆍΔhAr dev + 1.03 0.096 Δh Go' ctl 0.82ㆍΔhAr ctl + 1.44 0.133 Δh GM dev 0.99ㆍΔhL1 + 1.26ㆍΔhAr dev - 0.35ㆍΔvAr dev + 0.09 0.483 Δh GM ctl 1.07ㆍΔhL1-0.15 0.241 Δh Me' 0.89ㆍΔhL1-0.37ㆍΔhAg dev - 0.45ㆍΔvL6 ctl + 0.32ㆍΔvAg ctl - 0.16ㆍΔvAr dev + 0.34ㆍΔhMe + 0.76 0.819 Table 9. Results of stepwise multiple regression analysis for the vertical change of soft tissue points Equation R 2 Δv P dev 0.90ㆍΔvAg ctl - 0.18ㆍΔvGo dev + 1.26 0.335 Δv P ctl 0.78ㆍΔvAg ctl - 0.16ㆍΔvGo dev + 0.83 0.321 Δv UL - - Δv LL 0.19ㆍΔvL1 + 0.72 0.107 Δv Ch dev 0.27ㆍΔvGo ctl + 0.64 0.126 Δv Ch ctl - - Δv Go' dev 0.41ㆍΔvAg ctl + 0.29ㆍΔhGo dev + 0.39ㆍΔhL6 ctl -1.40 0.402 Δv Go' ctl 0.76ㆍΔvAg ctl + 0.62ㆍΔhL6 ctl - 1.67 0.349 Δv GM dev 0.43ㆍΔvMe + 0.50ㆍΔvAg dev + 0.25ㆍΔhGo dev - 0.84 0.586 Δv GM ctl 0.35ㆍΔvMe + 0.49ㆍΔvAg ctl - 0.27ㆍΔhMe - 0.53 0.542 Δv Me' 0.47ㆍΔvMe + 0.36ㆍΔvL6 dev - 0.35 0.582 260
Vol. 38, No. 4, 2008. Korean J Orthod 모든경조직계측점의변화를이용하여연조직변화를예측할수있는회귀방정식을산출하기위하여다중회귀분석을시행한결과 Table 8 과 9 의결과를얻었다. R 2 값이가장크게나타난계측점은수평변화의경우 Me', 수직변화의경우 GM dev 와 Me' 으로나타나 Me' 이수술후반응을가장정확히예측할수있는연조직부위임을알수있었다. 선택된경조직변화변수를연조직계측점별로살펴본결과연조직의수평방향변화예측에경조직의수직변화가사용되고, 연조직의수직방향변화예측에경조직의수평변화도사용됨을알수있었다. 아울러상관성을보이지않아예측이불가한경우도있는등전반적으로 R 2 값이낮은양상을나타내었다 (Tables 8 and 9). 고찰 술전, 술후경조직변화량과연조직변화량의상관관계를살펴본결과수평변화량의경우연조직변화량과가장많은경우에서유의한상관성을보인경조직계측점은 L6 dev, Me 그리고 L1 으로각각 5 개의연조직계측항목과유의성을보였다. 따라서이들계측점의변화를통하여연조직의수평변화량예측이상당부분가능하므로임상에서 model surgery 나 paper surgery 를통하여 L6 dev, Me 그리고 L1 의이동만잘계획하면비교적많은부분의연조직수평변화를예측할수있음을보여주었다. 그러나편위측이든반대측이든 Ar, Go, Ag 은소수의연조직계측항목과유의한상관성을보였으며, L6 ctl 는어느항목과도유의한상관성을보이지않아수평방향의연조직변화예측에도움이되지않는계측점임을나타내었다. 수평방향의연조직변화예측에는 L6 dev, Me, L1 이큰방향을미치므로경조직수술계획수립시보다정확한연조직반응예측을위해서는하악전치, 이부, 그리고편위측하악제 1 대구치의수평이동에보다세심한주의가필요함을알수있었다. 수직변화량의경우 L6 ctl, L1, Go ctl, Ag ctl 이 5-7 개의연조직계측항목과, 그리고 Me 과 L6 dev 이 3 개의연조직계측항목과각각유의한상관성을보여이들계측점이연조직수직변화량예측에유용하게사용될수있음을보여주었다. 서로인접하여위치하고있는 Go 과 Ag 을살펴본결과 Go 보다 Ag 이편위측과반대측모두에서보다많은연조직계측항목과유의한상관성을보이는것으로나타났는데, 이는경조직계측점설정시 Go 보다 Ag 에서수직방향의설정오차가적기때문인것으로추정된다. Go 은측모두부방사선사진상에서하악골의하연과하악상행지의측면에의해형성되는각을이등분하는선이하악골의윤곽과만나는점으로정의되는데이러한정의는정모두부방사선사진에그대로적용될수없으므로정모두부방사선사진에서는 Go 이하악우각부에서상행지윤곽의최하측방점으로바뀌어사용되어왔으며이러한정의의모호함으로인해조사자간또는조사자내재현도가낮은것으로생각된다. 실제로 Major 등 19 은정모두부방사선사진상계측점설정오차에관한연구에서 Go 의오차가매우큼을보고한바있으며, Legrell 등 20 은이러한오차로 Go 은정모두부방사선사진에서사용될수없음을주장하기도하였다. 특히 Go 은수직방향의오차가매우클것으로우려되는반면 Ag 의경우 Antegonial notch 의최상방점이라는정의를고려시수직방향의계측점선정오차가 Go 보다적으므로이러한차이가보다많은상관성에기여한것으로생각되었다. 연조직계측점별로가장상관성이높은경조직계측점을선택한결과바로하방의계측점이선택된경우는수평방향의경우 11 개연조직계측점중 LL 한항목에서만나타났으며나머지항목은멀리떨어진부위의경조직계측항목과짝을이루어정면연조직변화예측시에는 1:1 mean ratio 산출의미가희석되는양상을보였다. 임상에서수술계획을수립시경조직이동을 paper surgery 로시행하고이에따른연조직변화는직하방경조직과의 1:1 mean ratio 데이터를이용하여술후예상되는연조직윤곽을완성하는반면정면이미지에서는이러한방법이불가함을보여주었다. 한편가장높은상관성을보이는경조직계측점을연조직계측점별로선택한결과수평변화의경우하악전치 (L1) 가수직변화의경우경조직 menton 이각각가장많이선택된것으로나타나수술계획수립시보다정확한연조직변화예측을위해서는하악전치의수평이동그리고 menton 의수직이동에세심한주의가필요함을알수있었다. 바로하방에있는경조직계측점과짝을이룬수평방향의하악전치와수직방향의연조직 menton 의 1:1 mean ratio 을살펴보면각각 0.580, 0.642 로나타나경조직이동에대해연조직은수평방향이든수직방향이든 60% 내외로이동함을, 즉 100% 따라가지않음을알수있었다. 261
황현식, Jessica J. Lee, 황정현, 최학희, 임회정 대치교정지 38 권 4 호, 2008 년 모든경조직계측점의변화를이용하여연조직변화를예측할수있는회귀방정식을산출하기위하여다중회귀분석을시행한결과 R 2 값이가장크게나타난계측점은수평변화와수직변화모두에서 Me' 으로나타났다. 실제비대칭인지도에가장큰영향을미치는부위가이부인것을고려시 Me' 의설명력이가장크게나타난것은매우고무적인결과로생각된다. 한편 UL, LL 의경우수평변화예측은어느정도가능한반면수직변화예측에서는 cheilion 을포함하여매우작은값을보이거나회귀방정식산출이불가한것으로나타났는데이는하악전돌자의경우상하순의위치가전치부반대교합에의해불규칙하게영향을받기때문인것으로그리고수술로인한상하순의수직변화량이 0.02 또는 0.23 mm 로미미하기때문에나타난결과로생각된다. 아울러, 비록설명력은낮게나왔으나변화량자체가미미하므로수술후연조직변화예측에큰장애가되지는않을것으로생각되었다. 한편악교정수술후경조직변화에따른연조직변화를살펴본본연구에서술전자료는수술직전에채득하면되는반면술후자료채득시기결정을위해서는많은고려가있었다. 수술로인한종창이완전히가라앉지않은경우이로인해정확한연조직변화를파악할수없으므로연조직변화가없는시점을술후자료채득시기로할것을검토하였었다. 그러나실제임상에서일반적으로수술후한달째석고모형을포함한술후자료를채득하여그시점에서수술결과를평가하고차후교정치료계획을수립하는것을고려시이시기자료로연구를시행하는것이임상에직접적으로도움이될것으로판단하여술후자료채득시기를술후한달째로결정하였다. 아울러단순히수술이아닌 2 차감염등기타이유에의해종창이있는경우는연구대상에서제외하기로하고연구를시행하였으나본연구에서는한증례도해당되지않았다. 한편다중회귀분석을통하여얻은방정식은연조직예측가능성을높여주는장점이있는반면이를일일이계산하는것은매우번거로운일인바소위컴퓨터를이용한이미지시뮬레이션프로그램개발필요성이제기되었다. 그러나수술로경조직이동시술후연조직반응을미리예측해보는이미지시뮬레이션프로그램이개발되어임상에사용되고있는반면모두측면이미지뿐이어서안면비대칭등정면이미지시뮬레이션이필요한환자에서는애로가있어왔다. 주요연조직계측점별로수평및수 직변화량을예측할수있는방정식을산출한본연구결과는정면이미지시뮬레이션프로그램개발에유용하게사용될수있을것으로, 그리고임상에서안면비대칭환자의진단및치료계획수립에크게도움이될것으로기대된다. 결론 하악골악교정수술환자를대상으로술전및술후에정모두부방사선규격사진과얼굴사진을각각촬영한후, 술전및술후의방사선사진을이용하여경조직계측점의변화를, 얼굴사진을이용하여연조직계측점의변화를수평및수직으로구분하여각각측정한후연조직변화와경조직변화의상관성을분석하고이를이용하여경조직계측점변화에대한연조직계측점변화량인 1:1 mean ratio 을구하는한편, 모든경조직변화를이용하여연조직반응을예측할수있는다중회귀분석을시행하여다음과같은결과를얻었다. 1. 연조직변화와경조직변화의상관성을살펴본결과수평방향, 수직방향모두에서상관성이전반적으로낮게나타났다. 2. 1:1 mean ratio 산출을위하여서로상관성이가장높은경조직계측점을연조직계측점별로선택한결과직하방에있는경조직보다는다소멀리떨어져있는경조직계측점이선택되는경우가많이나타났다. 3. 가장높은상관성을보이는경조직계측점을연조직계측점별로선택한결과수평변화의경우하악전치가, 수직변화의경우경조직 menton 이각각많이선택되었다. 4. 경조직변화를이용하여연조직변화를예측할수있는회귀방정식을연조직계측점별로산출한결과연조직수평변화예측에경조직수직변화도사용되고연조직수직변화예측에경조직수평변화도사용되었다. 5. 연조직변화예측을위한회귀방정식산출결과수평과수직변화모두에서가장설명력이높은방정식은연조직 menton 에서나타났다. 경조직변화를이용하여정면사진에서연조직반응을예측하기위한본연구결과하부경조직계측점과상부연조직계측점의비율을이용하는 1: 1 mean ratio 방법은불가능한것으로나타난반면 262
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ORIGINAL ARTICLE Prediction of frontal soft tissue changes after mandibular surgery in facial asymmetry individuals Hyeon-Shik Hwang, DDS, MSD, PhD, a Jessica J. Lee, DDS, b Chung Hyon Hwang, DMD, MPH, c Hak-Hee Choi, DDS, MSD, d Hoi-Jeong Lim, MS, PhD e Objective: To aid the development of a frontal image simulating program, we evaluated the soft tissue frontal changes in relationship to movement of hard tissue with orthognathic surgery of facial asymmetry patients. Methods: Preoperative and postoperative frontal cephalograms and frontal view photographs of 45 mandibular surgery patients with facial asymmetry were obtained in a standardized manner. Vertical and horizontal changes of hard tissue and soft tissue were measured from cephalograms and photographs, respectively. Soft tissue change in result to hard tissue change was then analyzed. Results: Both vertical and horizontal correlation analysis showed a weak relationship between the changes. Hard tissue points that were picked for 1:1 mean ratio with soft tissue points did not show any significant relevance. For each soft tissue change, regressive equation was formulated by stepwise multiple regression analysis, and the equation for soft tissue Menton was most reliable in predicting changes. Both vertical and horizontal hard tissue changes were used together in prediction of vertical or horizontal soft tissue change. Conclusions: The results suggest that computerized image simulation using regression analysis may be of help for prediction of soft tissue change, while 1:1 mean ratio method is not useful. (Korean J Orthod 2008;38(4):252-264) Key words: Prediction of soft tissue change, Frontal cephalogram, Frontal photo, Facial asymmetry, Image simulation a Professor, Department of Orthodontics, 2nd Stage of Brain Korea 21, School of Dentistry, Dental Science Research Institute, Chonnam National University. b Assistant Professor, Department of Oral and Maxillofacial Surgery, School of Dentistry, University of Washington. c Research Scientist, Korean Adult Occlusion Study Center. d Graduate Student, e Professor of Biostatistics, Department of Orthodontics, School of Dentistry, Chonnam National University. Corresponding author: Hyeon-Shik Hwang. Department of Orthodontics, School of Dentistry, Chonnam National University, 8, Hak-dong, Dong-gu, Gwangju 501-757, Korea. +82 62 220 5486; e-mail, hhwang@chonnam.ac.kr. Received May 4, 2007; Last Revision November 2, 2007; Accepted November 5, 2007. 264