ISSN (print) 1226-8496 ISSN (online) 2288-3819 http://dx.doi.org/10.5933/jkapd.2014.41.1.54 Treatment of Transposition of the Maxillary Canine Using Various Treatment Modalities Hyosun Kim, Yoojun Kim, Kitaeg Jang, Youngjae Kim Department of Pediatric Dentistry, School of Dentistry, Seoul National University Abstract Transposition is a unique and extreme form of ectopic eruption where a tooth develops and erupts in a position, normally occupied by an adjacent tooth. Generally, three treatment options are available when the maxillary canine and first premolar are transposed. In the first treatment option, the transposed position of the teeth can be maintained such that the first premolar is moved to the position of the canine. Second, extraction of the maxillary first premolar can be considered. Third, the position of the transposed teeth can be corrected such that their normal positions in the arch are restored. Factors that should be considered in treatment modality decision include function, occlusion, periodontal support, treatment time, patient cooperation, and esthetic demands. This report describes cases of maxillary canine-premolar transposition treated with each of the three aforementioned treatment options. In the first case, transposed teeth were arranged in their transposed position. The second case was an extraction case. In the third case, orthodontic treatment and surgical repositioning were conducted. Key words : Tooth transposition, Maxillary canine, Orthodontic treatment Ⅰ. 서론전위는한영구치가정상적으로는다른영구치가있어야할위치에서발달하고맹출하는상대적으로드문치아위치이상중하나이다. 가장널리받아들여지는치아전위의병인은다인자유전에근거하는데, 그이유는가족력이있는경우가흔하고, 치아무형성증, 왜소치, 치아형태변형등의문제가전위된치아를가진환자에서높은비율로나타나기때문이다 1). 이외에도유치의만기잔존, 과잉치, 국소적병적진행상태등병인에대한여러가설이제안된바있다 2). 전위는완전전위와불완전전위로구분된다 3). 완전전위는두치아의치관과치근전체가바뀐위치에서평행하게관찰된다. 불완전전위에서는, 치관은그위치가바뀌어있으나, 치근 단은각각의정상적인위치에서관찰된다. 혹은, 치관이정상적인위치에있고, 치근단이전위된경우도이에포함된다. 이경우, 두이환된치아의치근은겹쳐보이고서로교차하여지나간다. 치아전위는편측에서발생하는경우가양측성보다많으며, 상악에호발한다. 상악의경우, 견치와제1소구치의전위가가장많으며, 측절치와견치의전위는그보다낮은빈도로발생한다 4). 흔하지않게중절치나제2소구치, 혹은제1대구치가연관되는경우가보고되고있다 5-7). 그러나중절치와측절치간전위와같은견치가연관되지않은증례는매우드물다. 가장많이보고되는상악견치와제1소구치전위의특징은다음과같다. 잔존된유견치가있는경우가많고, 영구견치는제1소구치와제2소구치사이에위치하며흔히협측에위치하고종종근심 Corresponding author : Youngjae Kim Department of Pediatric Dentistry, School of Dentistry, Seoul National University, 101 Daehak-ro, Jongno-gu, Seoul, 110-744, Korea Tel: +82-2-2072-3080 / Fax: +82-2-744-3599 / E-mail: neokarma@snu.ac.kr Received November 14, 2013 / Revised November 21, 2013 / Accepted November 27, 2013 54
순측회전되어있다. 전위된제1소구치는거의항상근심설측으로 90도까지회전되어있으며종종구개측에위치한다. 전위된부위에일시적인총생이존재하며, 특히유전치가잔존되어있을때그러하다 4). 치아전위의치료는치근첨의위치, 심미성, 환자의나이, 환자의치료동기및기대수준정도를평가하여결정한다. 또한, 치료도중일어날수있는치아와주위조직의손상가능성과치료기간또한고려되어야하고, 치료에앞서환자와이에대한상의가필요하다. 치료방법은전위된치아중하나를발치하는것, 치아를전위된위치에배열하는것, 그리고전위를완전히수정하여배열하는방법으로나뉜다. 마지막방법은외과적방법을동반하거나동반하지않을수있다. 본증례들은견치와제1소구치의전위로서울대학교치과병원소아치과에내원한환자들로서, 각각전술한치료방법중하나를사용하여양호한결과를얻었기에이에보고하는바이다. Ⅱ. 증례보고 1. 증례 1 11세 5개월된여아가상악양측견치의위치이상으로본원내원하였다. 파노라마방사선검사결과, 상악양측견치와제1 소구치의전위및하악양측제2소구치의맹출방향이상이관찰되었다. 3차원전산화단층촬영결과, 양측제1소구치의치근첨이견치치근의근심구개측에위치하고, 치관또한제1소구치가견치의근심에위치하는완전전위임을알수있었다 (Fig. 1). 이와관련하여가족력이나외상의병력은없었다. 교정검사결과, 골격성 3급부정교합및치성 1급부정교합으로진단되었다. 상악은양측유견치, 제1유구치, 좌측제2유구치발치후 Nance 구개호선을장착, 하악은양측제1유구치, 제2유구치발치후설측호선을장착하였다. 9개월후, 상악좌측견치를제외한모든영구치가출은하였으며 (Fig. 2a), Fig. 1. Panoramic and 3D dental CT view. Complete transposition of the bilateral maxillary canines and first premolars., The crowns of the first premolars were rotated mesiopalatally and their root apices were located mesially to the canines, respectively. Fig. 2. Intraoral clinical photographs. Before orthodontic treatment. After 2 months. The first premolars were moved mesially using an open coil spring while creating space for the canines. After 5 months. The leveling process of both canines was evident. 55
Fig. 3. Frontal and occlusal photographs after 18 months of treatment. Frontal view of the intraoral photograph. The midline is slightly deviated and the gingival line is esthetically compromised. In order to improve aesthetics, additional periodontal surgery was necessary. Occlusal view of the intraoral photograph. The canines and first premolars were aligned in transposed positions. Panoramic radiograph. The canines and first premolars were aligned without root resorption. 이에상, 하악치아에고정성교정장치를부착하였다. 상악양측제1소구치를 open coil을사용하여근심으로이동시켜견치가맹출할수있는공간을마련하고 (Fig. 2b), 교정장치부착 3개월경과후에상악좌우측견치에브라켓을부착하여함께레벨링을시행하였다 (Fig. 2c). 양측하악제2소구치는별다른견인없이자발적으로맹출하였으며, 고정성교정장치를통해회전조절을시행하였다. 19개월간의교정치료끝에상악양측견치와제1소구치는전위된위치로배열되었으며, 치근흡수는일어나지않았다 (Fig. 3). 2. 증례 2 10세 9개월된여자환아로앞니가고르지않음을주소로내원하였다. 내원당시상악좌, 우측유견치의잔존이관찰되었고, 방사선검사에서양측제1소구치의치근이견치의치근보다근심에위치함을알수있었다. 골격성 I급부정교합이며절단교합, 상악 5.9 mm 공간부족, 하악 5.9 mm 공간부족및중등도의양측성구순돌출을보였다 (Fig. 4). 또한, 하악의 3 전치가관찰되었다. 아직혼합치열기이며유견치의발거및변 형된 Nance 구개호선등을이용한견치의근심견인으로이루어질수있는차단교정이어려울것으로생각되어, 영구치열기에재평가하기로하고주기적으로관찰하였다. 26개월후, 영구치맹출이완료되었다. 전위된견치가제1소구치와제2소구치사이의협측에존재하였고방사선검사상완전전위로진단되었다 (Fig. 5). 상, 하악모두 5.9 mm의중등도의공간부족량을보임과상, 하순의돌출, 환아가개방교합경향을보임을고려하여상, 하악제1소구치를발거하였다. 상악제1대구치를횡구개호선으로고정원을보강한뒤상, 하악치아에고정성교정장치를부착하여교정치료하였다. 24 개월후, 하악 3 전치를유지한상태로치아의배열을마무리하였다 (Fig. 6). 환아는성장기환자로서치료후측모두부방사선검사분석결과, 많은수직적인성장과하악의후하방회전이일어났고하악평면각이증가하였다. 구순돌출도가개선되었고상악전치의각도가개선되었으나, 하악전치의공간을치료후반기에폐쇄한것의영향으로하악전치는설측경사되었다 (Table 1, Fig. 7). 교정치료종료후 2년 3개월후까지상악에가철성보정장치와하악에설측부착고정성유지장치를사용하여보정하였다. 56
Fig. 4. Initial radiographs. Panoramic radiograph. The root apices of the first premolars on both sides were located mesially to the canines. The mandibular right lateral incisor was missing congenitally. Lateral cephalogram. Cephalometric tracing. Moderate lip protrusion and upper incisor labioversion were observed. (d) Fig. 5. Initial records. Frontal view of the intraoral photograph. The overbite was shallow. Generalized crowding and the mandibular 3 incisor were observed. Left view of the intraoral photograph. The canine was located buccally between the first and second premolars. Right occlusal view of the intraoral photograph. The first premolar was rotated mesiopalatally. (d) Panoramic view before orthodontic treatment. Eruption of permanent teeth has been completed. Additionally, complete transposition of the canine and first premolar was observed. 57
Fig. 6. Final records. Panoramic view. The 4 first premolars were extracted and crowding was eliminated. Frontal view of the model. A midline discrepancy due to the mandibular 3 incisors was observed. Occlusal view of the model. The canine was aligned with extraction of the first premolar. Fig. 7. Post-treatment cephalogram. Lateral cephalogram. Vertical growth and an open bite tendency was observed. Cephalometric tracing. Lip protrusion was decreased. The maxillary and mandibular incisors were inclined lingually. Table 1. Summary of cephalometric analysis Measurement Norm Pretreatment Posttreatment SNA 81.0 ± 2.7 75.9 75.1 SNB 78.5 ± 2.7 74.7 68.8 ANB 2.5 ± 2.0 1.2 6.3 U1 to FHP ( ) 111 120.0 106.2 L1 to MP ( ) 96.0 ± 6.0 96.0 83.8 FMIA ( ) 67.0 ± 2.0 55.0 53.4 FMA ( ) 25.0 ± 2.0 28.9 42.7 UL to E. plane (mm) -0.5 ± 2.0 2.0 1.4 LL to E. plane (mm) 3.0 ± 1.7 4.8 4.0 Pretreatment records at age 10 years 9 months. Posttreatment records at age 15 years 3 months. 58
3. 증례 3 11세 3개월의남아가좌측상악견치의매복을주소로본원내원하였다. 구강내소견과더불어파노라마및 3차원전산화단층촬영방사선검사결과, 상악좌측견치와제1소구치의완전전위로진단되었다 (Fig. 8, 9). 교정검사결과, 골격성및치성 1급부정교합으로진단되었으며, 공간분석결과, 상악 0.8 mm, 하악 2.6 mm의공간부족을보였다. 상악우측중절치는환아가 9세경, 외상으로치관파절되어근관치료및복합레진수복한병력이있었다. 외과적노출과교정적견인만으로는견치와제1소구치의위치를바로잡는것이어려울것으로생각되어, 외과적재위치후교정치료하기로하였다. 국소마취하에좌측유견치를발거한후, 상악좌측견치의치관이제1소구치의근심에오도록치관을재위치시키고치근의이동은최소화하였다. 견치가구강내노출되도록봉합후, 레진강선고정을시행하였다 (Fig. 10). 좌측유견치는발거하였다. 수술 7주후, 상악에만고정성교정장치를부착하여치료하였다. 특히견치치근의이동에많은시간이소요되었다. 9개월경과후, 상악좌측견치와소구치가제 위치에배열되었고상악좌측견치의치수괴사는관찰되지않았으나, 상악좌측제1소구치치근의경미한근심만곡이관찰되었다 (Fig. 11). Ⅲ. 총괄및고찰상악견치는제1소구치와측절치의구개측상방및안와하방에서발달하기시작한다. 긴맹출기간에상악견치는근심순측으로이동하고순측전정높은곳에서촉진된다. 상악견치가이기간에정상적인맹출경로에서벗어나면, 매복되거나다른치아의위치로이동하여이소맹출되기도한다 8). 이렇게긴맹출경로는상악견치의잦은매복이나위치이상의주원인중하나로알려져있다 9). 상악견치의전위는치배가비정상적인위치에서발생하거나정상맹출경로로부터이탈하는것이그원인이된다 10). 상악견치와측절치의전위는주로유치열시기의안면외상에의하여발생하는경우가많은반면 11), 이른시기의외상이나치아의조기상실이상악견치와제1소구치의전위에기여한다는증거는없다 12). 상악견치와제1소구치의전위는치아전위의가장흔한종류이다. 이를치료하는방법은다양한데치아발거를동반하거 Fig. 8. Initial intraoral photographs. Frontal view. The maxillary right central incisor was discolored due to a history of trauma. Occlusal view. Primary canines on both sides are remained. With the exception of the canines, all permanent teeth in the arch were erupted. Left view. The left first premolar was rotated mesiopalatally. Fig. 9. Initial radiograph. Panoramic radiograph. The maxillary left canine was erupting between the first and second premolars. The maxillary right canine was erupting ordinarily. Reformatted localization CT. The maxillary left canine is located buccally to the first premolar. Intraoral radiograph. The canine and first premolar appeared to overlap. 59
(d) Fig. 10. Surgical repositioning of the canine. The maxillary canine was luxated using an elevator. The crown of the canine was repositioned to the mesial side of the first premolar. Resin-wire splinting was made. (d) 1 week after surgery. Uneventful healing was observed. Fig. 11. Final records. Panoramic radiograph. The root apex of the maxillary left first premolar is dilacerated due to the canine. The maxillary left canine showed pulp obliteration. (b, c) Intraoral photograph. The maxillary left canine and premolar were aligned in correct positions. 60
나동반하지않을수있다. 발치를동반한치료시에는심한치아우식증에이환되어있거나수복불가능한치아를우선하여발치한다. 만일이러한치아가없다면, 일반적으로제1소구치를발치하게된다. 이는총생을해소하고전위된견치의위치를쉽게바로잡을수있다는장점이있다. 또한, 더욱간단한역학을사용하여짧은시간안에치료를끝낼수있다. 그러나전치각도나환자의안모악화가능성이있는경우발치치료는제한된다. 비발치치료에서치아를전위된위치에배열하는방법은전위를수정하여배열하는방법보다대체적으로더짧은치료기간을요구한다. 단점으로견치와소구치의토크조절이어렵고하악운동시에교합간섭이있을수있다. 또한, 전위를수정하는방법보다심미적으로불리하다. 전위를바로잡아치아를제위치에배열하는방법은치료기간이더길고, 환자의협조가더많이필요할수있다. 그리고치주조직에손상을주지않고치근간섭없이전위를수정하는것이어려울수있다. 그러나이방법은, 완전한교두감합으로기능적인교합을달성할수있고심미적으로도이상적이다. 외과적재위치술또는자가치아이식을이용하여견치를제1소구치근심으로옮긴후, 교정치료로마무리하는방법은교정역학만을이용하여전위를바로잡는방법보다더비용-효율측면에서우수하고인접치의손상이없다는장점이있다. 그러나예후를예측하기힘들고치수괴사, 치근흡수, 유착의발생가능성이있으며, 이에따른치아의상실위험성이있다. 따라서치료방법선택시에는장, 단점을고려하여최선의선택지를결정하여야한다. 본 3 증례는모두완전전위가일어났으며, 견치의교두정이제1소구치의치근하방에위치하여차단교정을시행하기에는전위의발견이늦었다. 증례 1에서는초진시, 견치와제1소구치의치근각도가매우큰각으로발산되는위치에있음이발견되었다. 따라서치근의각도를조절하면서치아를원래의자리로배열하기에는무리가있어전위된위치로배열하였다. 이렇게전위된위치로견치와제1소구치를배열할경우, 치아의토크로인해심미성이저해되고, 하악운동중에교두간섭으로불편감을일으킬수있다는문제가있다. 그러나상대적으로짧은기간안에치근흡수나치주조직의손상우려없이치료를종료할수있다는장점이있다. 증례 1에서, 견치및소구치의토크조절과정중선일치등이마무리단계에서시행되어야했으나, 환자의협조도부족과브라켓주변탈회현상, 치은비대의문제로환아와보호자모두빠른치료종료를원하였다. 환아는제1소구치로인한이물감이나불편감을호소하지도않았고, 추가적인치료를원하지도않았다. 마무리단계에서교합조정을시행하였다. 치아전위시에악궁장경과치아크기의부조화가크고상, 하순돌출이있어발치교정이필요한경우, 전위된치아를발거하는방법도고려대상이될수있다. 증례 2의경우, 상, 하악모두중등도의공간부족을보였고, 상악전치의순측경사, 상, 하순의돌출, 골격성개방교합경향을보임을고려하였을때, 발치교정치료가적절하였다. 이때, 견치를발거하는것보다는제1소구치를발거하고견치를제자리로배열하는것이심 미적, 기능적으로유리하다. 하악의경우, 좌측측절치의선천적결손이있으므로좌, 우측소구치대신우측측절치하나를발치하는것도고려하였으나구순돌출도개선및최적의심미성, 교합의안정성을위해교정치료후성인기에하악전치임플란트및보철을하는것으로계획하였다. 더하여, 환아의개방교합성장경향을치아이동으로보상하기위한목적으로, 제 1소구치발치를최종결정하였다. 그러나치료중간에보철적처치가추가로필요치않도록치료를끝내달라는보호자의요청이있었다. 수평피개도증가와정중선의불일치, 안정성에영향을미칠수있음을설명하였으나치료후반기에하악전치의결손공간을폐쇄하게되었다. 치료중전치부개방교합은상악호선에역스피만곡, 하악호선에스피만곡을부여하고견치부위의수직적고무줄을이용하여치아치조보상을유도하여폐쇄하였다. 교정치료결과, 상악견치의토크및배열은심미적으로우수하였다. 그러나치료중간에치료계획을수정한것의영향으로하악전치의설측경사가일어났고, 초진과비교하여 5년동안많은수직적성장이일어나골격성개방교합의경향을보였다. 전위된치아를제자리에위치시키는방법으로여러증례가보고된바있다. Filho 등 13) 은분절호선으로견치의근심측이동, 제1소구치의구개측이동을개별적으로조절하여전위를교정하였으며, Oztoprak 등 14) 은교정용미니임플란트를식립하여제1소구치를구개측이동시킨후, 견치의근심이동및제 1소구치의원심이동으로전위를교정하였다. 적절한증례에서전위된치아를제위치에배열하는것은, 심미적으로나기능적으로가장좋은결과를낼수있으나, 치료기간의연장은피할수없다. 본증례 3에서는수술적인방법을이용하여견치를재위치시켰다. 이방법은교정만으로치아를배열하는것보다훨씬짧은치료기간을필요로한다. 또한, 자가치아이식술보다는치아에외상을덜주면서교정적견인으로원래의위치에배열할수있다. 본증례에서는견치의자가치아이식술도고려하였으나이를위해서는유견치발치공간이견치를이식하기에충분치않으므로추가적인골삭제가필요하였다. 따라서이경우, 견치의구강외노출시간증가와유견치발치와의치주인대상실이예상되고재부착 (reattachment) 보다는신부착 (new attachment) 에의한치주인대치유를기대해야한다. 그러나이러한과정없이도견치치관을충분히근심으로이동시켜고정할수있었으므로외과적재위치술만을시행하였다. 그러나뒤이은교정치료에서견치치근의각도조절이쉽지않았다. 자가치아이식술을시행했다면치근위치조절이더욱용이했을것으로생각된다. 본증례에서는견치의치수괴사가일어나지않았고결과적으로근관치료가필요치않았으며 9개월이라는상대적으로짧은기간내에교정치료가완료되었다. 그러나견치의토크조절불충분및부착치은감소등심미적인문제가있었다. 또한, 상악좌측제1소구치의치근은근심으로만곡되었으며이는치료전, 견치가제1소구치의원심협측에위치하여있던것의영향을받은것으로생각된다. 세증례모두가족력이나외상의병력은없었으나, 치아의선 61
천성결손및유치의만기잔존, 다른치아의맹출방향이상등이함께나타났다. 이는상악견치와제1소구치의전위가다인자유전모델에근거한유전적영향의결과로나타나며, 부분적무치증, 왜소측절치등부가적인치과적이상이높은빈도로존재함이이를뒷받침할수있다는 Peck 등의연구결과와일치한다 15). Ⅳ. 요약치아전위는치열궁내의두인접치의위치가바뀐것으로이에대한교정적치료를할때에는심미, 기능, 인접치의치주조직손상가능성, 치료기간등을고려하여전위된치아를제자리에배열할것인지, 바뀐위치에배열할것인지를결정해야한다. 본증례들에서는치아를변위된상태로배열하는방법, 전위된두치아중한치아를발거하고교정하는방법, 외과적재위치와교정치료를통한배열방법을통하여각각양호한결과를얻었다. References 1. Peck L, Peck S, Attia Y : Maxillary canine-first premolar transposition, associated dental anomalies and genetic basis. Angle orthod, 63:99-109, 1993. 2. Farret MM, Farret MM, Hollweg H, et al. : Unusual orthodontic approach to a maxillary canine-premolar transposition and a missing lateral incisor with longterm follow-up. Am J Orthod Dentofacial Orthop, Nov;142:690-7, 2012. 3. Shapira Y, Kuftinec MM : Tooth transpositions: a review of the literature and treatment considerations. Angle Orthod, 59:271-276, 1989. 4. Shapira Y, Kuftinec MM : Maxillary tooth transpositions: characteristic features and accompanying dental anomalies. Am J Orthod Dentofacial Orthop, Feb;119:127-34, 2001. 5. Jackson M : Upper canine in position of upper central incisor. Br. Dent J, 90:243, 1951. 6. Joshi MR, Gaitonde SS : Canine transposition of extensive degree: a case report. Br Dent J, 121:221-2, 1966. 7. Hallet GE : A maxillary canine erupting in the first molar region. Br Dent J, 72:191-2, 1942. 8. Dewel BF : The upper cuspid: its development and impaction. Angle Orthod, 19:79-90, 1949. 9. Ooë T: Human tooth and dental arch development. Tokyo: Ishiyaku Publishers, 1981. 10. Mader C. Konzelman JL : Transposition of teeth. JADA, 98:412-413, 1979. 11. Van Gool AV : Injury to the permanent tooth germ after trauma to the deciduous predecessor. Oral Surg Oral Med Oral Pathol, 35:2-12, 1973. 12. Singh GP, Sharma VP, Singh GK, et al. : Maxillary canine-first premolar Transposition - Orthodontic Management - A Case Report. J Ind Orthod Soc, 39:14-19, 2006. 13. Filho LC, Cardoso MA. An TL, Bertoz FA : Maxillary canine-first premolar transposition. Angle Orthod, 77:167-175, 2007. 14. Oztoprak MO, Demircan C, Arun T : Correction of a maxillary canine-first premolar transposition using mini-implant anchorage. Korean Journal of Orthodontics, 41:371-378, 2011. 15. Peck L, Peck S, Attia Y : Maxillary canine-first premolar transposition, associated dental anomalies and genetic basis. Angle Orthod, 63:99-10, 1993. 62
국문초록 다양한치료법을사용한상악견치전위의치료 김효선 김유준 장기택 김영재 서울대학교치의학전문대학원소아치과학교실 치아전위는치아이소맹출의극단적인형태로, 인접한두치아의위치가서로바뀐상태로발육하고맹출하는치아위치이상이다. 상악견치와제1소구치의전위가가장흔하게발견되는데, 이는다음의세가지방법으로치료할수있다. 첫번째방법은치아를전위된상태로배열하는것이며, 두번째방법은전위된두치아중한치아를발치하고교정치료하는것이다. 세번째는, 전위된치아를원래의위치로되돌려배열하는방법이다. 치료방법을결정할때에는기능, 심미, 지지치주조직의손상가능성, 치료기간, 환자의협조도, 환자의심미적요구도를고려하여야한다. 본증례는견치와제1소구치간의전위가일어난환자세명의교정치료에관한것으로, 각기다른치료방법을사용하여양호한결과를얻었기에이에보고하는바이다. 주요어 : 전위, 상악견치, 교정치료 63