CASE REPORT eissn 2384-1230 https://doi.org/10.33777/cjkao.2019.9.3.151 전방부분절골절단술로인한의원성외상치아의교정적이동 홍석윤, 김영호, 채화성 아주대학교임상치의학대학원치과교정학교실 A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Seok Yoon Hong, Young Ho Kim, Hwa Sung Chae Department of Orthidontics, Institute of Oral Health Science, Ajou University School of Medicine, Suwon, Korea ABSTRACT When extraction treatment is planned in patients with lower three incisors, three premolars extraction is widely accepted. In this case report, moving traumatized teeth to close the orthodontic residual space after anterior segmental ssteotomy (ASO) will be presented. The patient underwent ASO and was referred for orthodontic treatment after three months. #14, 24, 34 was extracted, and a surgical attempt to separate #43 and #44 was noted. Upon clinical exam, teeth discoloration of #23, 33, 44 was evident. In addition, radiographs, including CT revealed that the surgical line was quite approximated to the root surface, especially to #44. No symptoms were noted. Possibility of PDL damage was suspected, regarding ankylosis and trauma. Although panorama and periapical X-rays showed poor prognosis of those teeth, CT sectioning indicated no obvious root damage. Furthermore, the patient insisted that her lips were more retracted than she expected. Thus, molars protraction to close the residual space was necessary. Clinical examination also demonstrated of 3 mm anterior open bite, lower three incisors, and residual space of 5 mm in the upper and 2 mm in the lower arch. Biomechanically, it is hard to perform molars protraction while closing anterior open bite. Maxillary incisors brackets were positioned upside-down (0.022-inch slot MBT, -17 ) to increase upper incisal show and also to consider further maxillary full-arch protraction due to the patient complaint. To achieve molars protraction and intrusion simultaneously, protraction TPA with high positioned solder hooks were designed and delivered. TPA protraction was attempted first to test the possibility of ankylosis before full treatment. Superimposition revealed that the molars were successfully intruded and protracted, which contributed to the mandibular plane closing effect. A successful substitution for #43 to #42 and acceptable occlusion was obtained. Careful examination of CT sectioning helps orthodontic treatment of surgically traumatized teeth. Diagnostic molar protraction followed by active intrusion helps to achieve acceptable outcomes. () Key words Anterior segmental osteotomy, Trauma, Cone-beam CT, Three incisors Dr. 홍석윤 Dr. 김영호 Dr. 채화성 Corresponding author: Hwa Sung Chae Department of Orthidontics, Institute of Oral Health Science, Ajou University School of Medicine, 164 Worldcup-ro, Yeongtong-gu, Suwon 16499, Korea Tel. +82-31-219-4111 E-mail. hwasungchae@gmail.com Received: July 24, 2019 / Revised: August 22, 2019 / Accepted: August 22, 2019 Copyright c Korean Association of Orthodontists 151
서론 전방부분절골절단술은치조골돌출의치료방법중하나로서, 술후입술의돌출도가상당히해소되고심미적으로우수한결과를보여각광받고있는술식이다. 일반적으로좌 우측소구치를발거한후해당치조골을삭제하기때문에, 소구치의폭경만큼치조골돌출해소가가능하다. 1-3 술후남는발치공간의폐쇄와부가적인배열및마무리작업을위해교정치료가필요하다. 전방부분절골절단술의가장흔한부작용은술후혈류저하로인한인접치치수괴사로알려져있다. 4 또한골절단시원심경사된치근일부를절단선에포함시킬경우해당치아의치수괴사나치근흡수가예상된다. 치수괴사로인해근관치료를한치아의교정적이동은정상치아와큰차이없이가능하다고알려져있으나, 4 골절단으로인해혈류공급이저하되어치수질환이생기는경우교정적이동이가능한지에대해서는알려진바가거의없다. 많은양의입술돌출해소를위해발치한치아의폭경대부분을수술량으로사용할목적으로, 절단선을인접치가까이설정하는경우치주인대강이의도치않게침범될수있다. 치주인대는교정력이가해졌을시압박과인장에따른혈류변화로골을괴사, 생성시켜치아의이동을가능하게한다. 5 때문에치주인대가손상된치아는교정적이동이어려울것으로예상할수있다. 본증례는하악 3전치의심미적교정치료전략과더불어, 전방부분절골절단술후치주인대강의손상및치수질환이의심되는치아의교정적이동을다루었다. 하악 3전치의경우다양한접근법이가능하다고할수있지만, 본저자는가급적하악견치하나를측절치로치환하는방법을선호한다. 이러한방법으로과도한수평피개가남는것을방지할수있으며최대한의교합관계를얻을수있는장점이있다 (Figure 1). 하악좌측과우측견치중어느쪽을측절치로치환할것인지에대한선택이필요한데, 아래 3가지기준의평가를통해결정하는것이바람직하다. 본증례에서처럼미리하악좌측제1소구치가발치된경우에는우측견치를측절치로치환하여교합을완성하는것외에는선택의여지가없으나, 다음의평가를통해우측견치를측절치로치환하는것이유리함을확인하였다. 1) 하악전치부의치축경사 : 하악전치부의치근첨의이동을최소화하는방향. 본환자에서는하악전치 3개치근이좌측경사되어있으므로우측견치를측절치로치환함이합리적이다. 2) 입술의볼륨차이 : 임상소견상볼륨에차이가보인다면, 더작은쪽의견치를전방이동시켜볼륨차이를줄인다. 본환자에서는초진시우측하순볼륨이작으므로하악우측견치를측절치로치환함이또한합리적이다. 3) 악궁의비대칭성 : 하악궁이비대칭이라면, 넓은쪽의견치를측절치로치환한다. 견치를측절치로이동하려면공간이필요한데이미넓은쪽에서는악궁이좁아지게되며, 좁은쪽에서는넓어지며공간이생기므로이공간으로견치가이동하기용이하다. 본환자에서는우측전치부수평피개가작고상하악우측견치에서반대교합을이루고있어서하악우측의견치를측절치로치환하기로결정하였다. 진단 22세여자환자가타의료기관에서전방부분절골절단술후 3개월지나본원에내원하였다. 환자의입이생각보다과하게들어가보인다는주소로내원하였으며, 특이할전신병력은없었으며좌측과두에퇴행성변화가관찰되었으나다른임상적증상은나타나지않았다. 초진시시행한임상검사시직선적인안모 (straight profile) 와후퇴된윗입술이관찰되었다. 눈에띄는악골비대칭은관찰되지않았으며안정시상악전치노출량은 2.5 mm였다. 구강내소견으로는상악양측에 152
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. Figure 1. An example of the lower three incisors case treatment through left canine substitution. 153
각각 1.5 mm의잔여공간이, 하악에서는좌측에약 2 mm의잔여공간, 그리고우측에약 1 mm의크라우딩이관찰되었다. 다소부족한수평피개도와약 2 mm의전치부개방교합이관찰되었다. 하악우측측절치는선 천적결손으로판단되었으며, 이에따라상악양측제1 소구치및하악좌측제1소구치의발치가시행된것으로생각되었다 (Figure 2). 비순각을측정했을때 110 ( 정상 100 ) 로둔한각을보였다. 심미선을기준으로상 Figure 2. Pretreatment facial, intraoral photographs, and cast models. 154
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. 순은 -3.5 mm( 정상 -1 mm), 하순은 0 mm( 정상 2 mm) 로모두후퇴된위치에있었다. 경조직을관찰하였을때, A point to N-perpendicular line은 -7.5 mm( 정상 0 mm), Pogonion to N-perpendicular line은 -12 mm( 정상, -5 mm) 로역시후퇴되어있음을확인할수있었다 (Table 1). 상악좌측견치, 하악좌측견치및우측제1소구치의회백색치아변성이관 찰되었다. 환자는해당치아에서타진시약간의불편감을느꼈으며, 치수생활력검사에서는음성을나타내었다 (Figure 3). 치근단방사선사진및콘빔전산화단층촬영 (cone-beam computed tomography) 영상에서상악좌측견치와하악우측제1소구치에서치근의손상은관찰되지않았으나치주인대의손상이의심되었다 (Figure 4). Table 1. Cephalometric measurements Measurement Mean S.D. Initial Final Vertical skeletal pattern Björk sum 393.3 5.2 394.64 392.91 Saddle angle 125.9 4.4 121.94 121.96 Articular angle 148.7 5.7 159.03* 157.01* Gonial angle 126 2 113.68 113.94 Antero-post. FHR 61 3 65.82 66.07 Lower ant. FHR 55.4 1.7 54.03 54.19 FMA 24.2 4.6 27.01 26.64 Mn. plane angle (to SN) 33.3 5 34.64 34.22 Horizontal skeletal pattern A to N-perp. 0 1-7.50-7.27 Pog to N-perp. -5 1-13.28-11.02 SNA 81.6 3.1 76.57* 76.14* SNB 79.1 3 75.53* 76.45 ANB 2.4 1.8 1.04-0.31* Wits -2.7 2.4-4.89-6.58* Mn. body length 78 4.3 84.66 84.66 Body to ant. cranial base ratio 0.94 0.26 1.06 1.06 Denture pattern UOcc. plane to U1 58 2 52.06** 54.69* LOcc. plane to L1 66.1 5.2 68.67 69.64 U1 to SN 107 6 107.08 101.66 U1 to FH 116 5.7 114.67 109.17* U1 to A-Pog 7.8 2.2 10.11* 7.14 Ui to Stm 2.73 1.17 5.09** 2.50 IMPA 95.9 6.3 100.08 98.39 L1 to A-pog 3 2 6.34* 5.36* Interincisal angle 124 8.3 118.24 125.80 Upper occl plane to FH 14 5 13.26 16.14 Bisecting occl plane to FH 14 5 14.71 14.49 Soft tissue profile Upper lip EL -1 2-3.54* -4.86* Lower lip EL 2 3 0.08-2.22* Interlabial gap 0.1 0.5 6.81 1.01* Nasolabial angle 100 2 110.64* 109.20* FA B A 81 2.78 78.76 78.51 155
Figure 3. Pretreatment radiographs. 156
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. Figure 4. Pretreatment CBCT images of maxillary left canine and mandibular right first premolar. 치료계획 내원당시상악양측제1소구치, 하악좌측제1소구치가발치되어있었으며하악제1소구치는좁은공간의골절단이원인으로보이는변색소견을보였다. 환자가전치의과도한후퇴를호소하였으므로상악경구개부에미니임플랜트를식립하여잔여발치공간폐쇄및 전치열전방이동을계획하고, 전치부개방교합의해소를위해횡구개호선훅을후하방으로위치시키도록하였다. 상악좌측견치, 하악좌측견치와하악우측제1소구치의치수괴사가의심되었으나, 세균감염으로인한괴사가아니므로신경치료는서둘러서진행하지않기로하였다. 157
치료경과및결과치료경과 치료첫날미니임플랜트 2개를경구개부에식립하고상악제1대구치에횡구개호선을장착하였다. 전방개방교합이있었기때문에미니임플랜트의높이를횡구개호선의훅보다전상방위치시켜구치부함입도같이목표하였다. 상악양측제1대구치에는브라켓기울기와와이어벤딩을통해치체이동과압하이동이동시에일어날수있도록유도하여조기접촉에의해전치부개방교합이발생하는것을방지하며구치부의전방이동을도모하였다. 상악양측제2대구치는횡중격섬유에의한전방이동을유도하여, 공간이벌어지면결찰와이어로양측제1대구치와결찰하는방법으로전방이동을진행하였다 (Figure 5). 이러한상악의횡구개호선과미니임플랜트를활용한전방이동은치료초기부터바로실행하여 regional acceleratory phenomenon (RAP) 현상을최대한활용하려고노력하였다. 하악은우측제1소구치를제외한치열에 0.022-inch 슬롯 Damon 브라켓을접착하였다. 첫와이어는 0.016-inch 니켈- 티타늄와이어를결찰하였다. 한달후하악에서는 0.018 0.025-inch Bioforce 와이어를결찰, 상악에서는전치열에브라켓을접착하고 0.016-inch 니켈-티타늄와이어를결찰 하였다. 상악전치부브라켓은위 아래를뒤집어접착하여전치열전방이동시전치부개방교합을심화시키지않는치체이동을도모하였다. 상악좌측견치, 하악좌측견치와하악우측제1소구치등의치근흡수에유의하며주기적인방사선사진을촬영하면서교정치료를계속하였다. 치료시작 5개월후, 추가적인치근흡수나증상이나타나지않아하악우측제1소구치도브라켓을접착한후다시와이어를 0.014-inch 니켈- 티타늄와이어로바꾸었다. 이후 0.016-inch 니켈- 티타늄와이어, 0.018 0.025-inch Bioforce 와이어, 0.019 0.025-inch 니켈-티타늄와이어, 그리고 0.018 0.025-inch 스테인리스강와이어로진행되었다. 각형스테인리스강와이어상에서상 하악모두활주역학으로잔존공간을폐쇄하였다. 약 9개월간상악치열을전방이동한후재평가했으나, 환자가더이상의입술전방이동을원하지않고인중이다소짧아더이상의전방이동이있을경우입을다물기힘들것으로예상되어전후방적위치를유지하기로하였다 (Figure 6). 마무리작업까지약 15개월간의교정치료를끝내고하악우측견치를측절치로대체하기위해교합및형태를조절하였다. 치료후콘빔전산화단층촬영영상에서비정상적치근흡수등의문제는나타나지않아고정식유지장치와환상유지장치를사용하여유지관리하였다. Figure 5. A design for protraction, intrusion and bodily forward movement of maxillary molars. 치료결과양측견치관계와구치관계는모두제I급구치관계를나타냈으며, 전치부개방교합도해소되었다 (Figures 7-9). 치료전후중첩과계측치비교에서, 계획한대로상악구치는전상방이동했으며상악전치는주로치근의전방이동이이루어졌다. 하악은우측치열이좌측이동하며하악우측견치를측절치로치환함과함께약간의전치부후방이동이일어났으나하악골의반시 158
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. Figure 6. Facial and intraoral photographs, and panoramic radiograph at 9 months after treatment. 159
Figure 7. Posttreatment facial, intraoral photographs and cast models. 160
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. Figure 8. Posttreatment radiographs. 계방향회전으로하악전치의전후방적위치는유지되었다 (Figure 10, Table 1). 고찰 본환자의초진진단시임상적으로치아변색소견이관찰되어파노라마방사선사진에서의상악좌측견치, 하악좌측견치및우측제1소구치등의의원성손상이심한것으로판단되었으나, 콘빔전산화단층촬영영상에서는백악질의손상이경미해보여교정적치아이동이가능한것으로판단되었다. 감염의증거가없고외상이나치아이동에의해치아의변색이일어난경우, 별다른처치없이경과를지켜보았을때변색의정도가 개선되거나 (33.3%) 유지되고 (66.6%) 치수생활력도일부치아에서회복된다는보고 6 가있으므로본논문의환자에서성급한치수치료는진행하지않았다. 치료종료후콘빔전산화단층촬영영상에서초진시이환되었던것으로판단되었던치아들이정상소견을보였다. 따라서외상치의교정적합병증에관한 3차원적진단에는콘빔전산화단층촬영이필수라고판단된다. 치료생역학적관점에서볼때전치부개방교합이있는상황에서상악구치의전방이동시교합간섭에의한추가적인개방교합의가능성과골절편의치아근접성및치아변색등을고려하여, 주로상악제1대구치에횡구개호선을통해힘을전달하고상악제2소구치와제2대구치는제1대구치의이동에의해수동적으로함께 161
Figure 9. Posttreatment CBCT images of maxillary left canine and mandibular right first premolar. 162
A Case Report: Orthodontic Treatment of Iatrogenic Trauma Teeth Caused by Anterior Segmental Osteotomy Hong et al. Figure 10. Superimposition of the lateral cephalograms before and after treatment. 이동하는방식으로치아및지지조직의추가적인손상없이계획한치아이동을유도할수있었다. 초진시골격성 III급부정교합을동반한전치부개방교합을개선하고자하악골의반시계방향회전을유도하는치료는전치부개방교합의개선에는효과가있으나하순의전방이동을초래할수있지만, 입술부전이개선되면하순의돌출감이줄어들수있다. 중첩사진 (Figure 10) 을보면하순의위치가이 2가지요인의조합으로유지된것으로판단된다. 또한초진시개방교합의범주가실활치로보이는견치, 소구치등을포함하고있어, 해당치아들을수직적으로정출시키는것은치료의안정성과치아의안전을위협할수있으므로상악구치의함입이동을주된전치부개방교합의치료방향으로설정하였다. 하악 3전치증례에서견치를소구치로대체하고자하는경우치아크기비율 (Bolton discrepancy) 을고려해야하는데, 본증례에서는하악우측견치를측절치로대체하였을때견치간에는 0.78, 제1대구치간에는 0.85 의하악의치아크기과잉이발생하였다. 이는 주로하악우측견치의치관크기가하악우측전치보다크기때문으로판단되어치간삭제를시행하였다. Elemartix set up에서가상치료를한대로하악우측견치를 1.5 mm 근심으로위치시켰을때구치부가안정적인교합을이룰수있었고, 치료결과에서도거의유사한교합을얻었다 (Figures 6, 11). 결론 방사선사진에서치주인대의손상이의심되고, 치수생활력검사에서음성을나타내는치아에서도교정치료의반응성은임상을통해진단해보면서치료를진행할수있다. 또한 III급전치부개방교합에서구치부의전방이동으로발치공간폐쇄를시행할때에는구치부의압하를동반한개방교합의폐쇄가필요하다. 따라서본증례에서는외상치아의정출을최소로하면서상악구치의압하를동반한전방이동을시행하였다. 하악 3전치증례는다양한치료계획이가능한데, 외 163
Figure 11. Set up using Elematrix software. 상치의이동을최소화하며, 셋업상에서가장교합에유리한방법을모색하여, 하악우측견치를측절치로대체하여치열을교정하였다. REFERENCES 1. Jayaratne YS, Zwahlen RA, Lo J, Cheung LK. Facial soft tissue response to anterior segmental osteotomies: a systematic review. Int J Oral Maxillofac Surg 2010;39: 1050-1058. 2. Shawky MM, El-Ghareeb TI, Hameed Abu Hummos LA. Evaluation of the three-dimensional soft tissue changes after anterior segmental maxillary osteotomy. Int J Oral Maxillofac Surg 2012;41:718-726. 3. Park JU, Hwang YS. Evaluation of the soft and hard tissue changes after anterior segmental osteotomy on the maxilla and mandible. J Oral Maxillofac Surg 2008;66:98-103. 4. Nemcovsky CE, Beny L, Shanberger S, Feldman- Herman S, Vardimon A. Bone apposition in surgical bony defects following orthodontic movement: a comparative histomorphometric study between root- and periodontal ligament-damaged and periodontally intact rat molars. J Periodontol 2004;75:1013-1019. 5. Thilander B, Rygh P, Reitan K. Tissue reactions in orthodontics. In: Graber TM, Vanarsdall RL, Vig KW, editors. Orthodontics: Current Principles and Techniques. 4th ed. St. Louis: Elsevier; 2005. 6. Baik UB, Kim H, Chae HS, Myung JY, Chun YS. Teeth discoloration during orthodontic treatment. Korean J Orthod 2017;47:334-339. 164