Int. J. Oral Maxillofac. Surg. 2014; 43: 739–741 http://dx.doi.org/10.1016/j.ijom.2014.01.005, available online at http://www.sciencedirect.com
Technical Note Orthognathic Surgery
Surgical acrylic guide for distractor positioning
T. Baykul1, M. A. Aydın2, Y. Fındık1, 1
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Su¨leyman Demirel University, Isparta, Turkey; 2 Department of Plastic and Reconstructive Surgery, Faculty of Medicine, Su¨leyman Demirel University, Isparta, Turkey
T. Baykul, M.A. Aydın, Y. Fındık: Surgical acrylic guide for distractor positioning. Int. J. Oral Maxillofac. Surg. 2014; 43: 739–741. Crown Copyright # 2014 Published by Elsevier Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. All rights reserved. Abstract. Internal maxillary distraction with the Le Fort I osteotomy is a technique that can provide simultaneous skeletal advancement and gradual expansion of the soft tissue. For calibrating the vectors of the internal distractors and transferring the desired vectors to the patient, surgical guides may be fabricated before surgery on a stereolithographic model. The anterior nasal spine may be used as a critical anatomical landmark for applying this type of surgical guide.
Maxillary hypoplasia is a deficiency that usually manifests in more than one plane, requiring three-dimensional (3D) correction of the deformity. This skeletal problem can be treated with a Le Fort I osteotomy, followed by maxillary repositioning and stabilization with internal plate fixation in patients with permanent dentition.1 Maxillary distraction osteogenesis is indicated in severe angle class III malocclusions and severe maxillary hypoplasia among some cleft patients and those with other craniofacial deformities.2 Distraction osteogenesis has some advantages, such as easy advancement of the maxilla, being easy and safe for large advancements, and achieving stable results. During Le Fort I distraction osteogenesis, placement of the distractor in the correct position and then disconnecting it before the osteotomy is a difficult procedure and lengthens the operation time. A surgical guide placed on the anterior nasal spine (ANS) may be useful for carrying the correct position obtained on the 3D model to the patient’s maxilla. At the same time, it may simplify the technical difficulties and 0901-5027/060739 + 03 $36.00/0
may shorten the operation time. We present a transparent acrylic surgical guide placed on the ANS for these purposes in Le Fort I distraction osteogenesis. Technique
Planning of the operation was done on the patient’s 3D model and the distractors were chosen bilaterally for Le Fort I distraction. After marking the osteotomy line, the distractors were placed on the model and then the distractor plates were contoured to fit the model and fixed with screws. Next, the distractors were disconnected and the transparent acrylic surgical guide was prepared on the 3D model (Fig. 1). To prepare the surgical guide, self-curing acrylic resin was attached on both sides of the maxilla and oriented according to anatomical landmarks, such as the ANS. The position of the surgical guide was secured on the model according to reference points, such as the ANS and the contours of the lateral maxillary wall. The acrylic plate fitted tightly to the nasal spine like a mortise and tenon system
Key words: distraction osteogenesis; maxilla; surgical plate. Accepted for publication 9 January 2014 Available online 10 February 2014
(Fig. 2). After the surgical guide was fitted to the model, the screw holes of the distractor plates were marked and opened on the guide using a bur. During the operation, the planned position of the distractor was carried to the patient’s maxilla using the transparent acrylic guide and this was easily adapted to the patient’s maxilla with the previously created mortise and tenon system using the ANS. The screw holes that were marked on the acrylic guide were opened before the Le Fort I osteotomy. The osteotomy was performed after opening the holes; the maxillary distractor was then placed in the correct position very easily. After the activation phase of the distraction osteogenesis, planned vectors and directions could be achieved and hence the maxilla was located in the desired position (Fig. 3). Discussion
Several preoperative procedures are useful in the planning of distractor positioning and alignment. Computed tomography
Crown Copyright # 2014 Published by Elsevier Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. All rights reserved.
740
Baykul et al.
Fig. 1. The acrylic plate fitted tightly to the nasal spine like a mortise and tenon system.
scans, dental models, cephalometric tracings, and 3D anatomical models are beneficial in determining the location of the osteotomy and placement of the distractor devices. 3D anatomical models have been used as successful hands-on tools for contouring the distractor plates, aligning the distractors, calibrating the desired vectors of distraction, and making the osteotomy prior to surgery. These advantages also reduce the operation time, and surgeons can determine the correct and accurate
Fig. 2. The acrylic surgical guide that had been prepared on the 3D model was placed on the model.
placement of the distractor in the model surgery before the operation. On the other hand, in the use of the 3D models, surgical guides may be prepared for carrying the correct position of the distractors from the 3D model to the patient’s maxilla, as presented here. Using a transparent acrylic surgical guide, it is possible to safely carry the contoured distractor plates, aligned distractors, and calibrated distraction vectors from the 3D model to the patient’s maxilla with the aid
of the screw holes marked on the guide. The use of a surgical template for transferring the distractor to the patient has been reported in several cases in the literature; the additional feature of the guide presented here is the use of the ANS as a guide during transfer in the operating room.3–6 The ANS may be used as a critical anatomical landmark for applying this type of surgical guide. By creating such a tenon–mortise system using the anatomical shape of the ANS, stabilization and adaptation of the surgical guide is very easy in such cases. During the operation, after drilling the bone with the use of the marked screw holes on the guide, the osteotomy may be performed and then the distractors may be fixed. At the same time, since placement of the distractor for positioning and then disconnecting it before the osteotomy is unnecessary, the use of such a guide may shorten the operation time, avoid the complications of general anaesthesia, and simplify the technique. Funding
None. Competing interests
None declared. Ethical approval
Not required.
Fig. 3. Planned vectors and directions could be achieved and so the maxilla was located in the desired position.
Patient consent
Not required.
Surgical acrylic guide for maxillary distractor References 1. Yamauchi K, Mitsugi M, Takahashi T. Maxillary distraction osteogenesis using Le Fort I osteotomy without intraoperative down-fracture. Int J Oral Maxillofac Surg 2006;35: 493–8. 2. Keßler P, Wiltfang J, Schultze-Mosgau S, Hirschfelder U, Neukam FW. Distraction osteogenesis of the maxilla and midface using a subcutaneous device: report of four cases. Br J Oral Maxillofac Surg 2001;39:13–21. 3. Iida S, Kogo M, Aikawa T, Masuda T, Yoshimura N, Adachi S. Maxillary distraction osteogenesis using the intraoral distractors
and the full-covered tooth-supported maxillary splint. J Oral Maxillofac Surg 2007;65: 813–7. 4. Herford AS. Use of a plate-guided distraction device for transport distraction osteogenesis of the mandible. J Oral Maxillofac Surg 2004;62:412–20. 5. Bae MJ, Kim JY, Park JT, Cha JY, Kim HJ, Yu HS, Hwang CJ. Accuracy of miniscrew surgical guides assessed from cone-beam computed tomography and digital models. Am J Orthod Dentofacial Orthop 2013;143: 893–901. 6. Kofod T, Pedersen TK, Nørholt SE, Jensen J. Stereolithographic models for simulation and
741
transfer of vector in vertical distraction of the mandibular ramus: a technical note. J Craniofac Surg 2005;16:608–14.
Address: Y. Fındık Department of Oral and Maxillofacial Surgery Faculty of Dentistry Su¨leyman Demirel University Isparta Turkey Tel: +90 246 2113251; Fax: +90 246 2370607 E-mail: [email protected]
Technical Note Orthognathic Surgery
Surgical acrylic guide for distractor positioning
T. Baykul1, M. A. Aydın2, Y. Fındık1, 1
Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Su¨leyman Demirel University, Isparta, Turkey; 2 Department of Plastic and Reconstructive Surgery, Faculty of Medicine, Su¨leyman Demirel University, Isparta, Turkey
T. Baykul, M.A. Aydın, Y. Fındık: Surgical acrylic guide for distractor positioning. Int. J. Oral Maxillofac. Surg. 2014; 43: 739–741. Crown Copyright # 2014 Published by Elsevier Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. All rights reserved. Abstract. Internal maxillary distraction with the Le Fort I osteotomy is a technique that can provide simultaneous skeletal advancement and gradual expansion of the soft tissue. For calibrating the vectors of the internal distractors and transferring the desired vectors to the patient, surgical guides may be fabricated before surgery on a stereolithographic model. The anterior nasal spine may be used as a critical anatomical landmark for applying this type of surgical guide.
Maxillary hypoplasia is a deficiency that usually manifests in more than one plane, requiring three-dimensional (3D) correction of the deformity. This skeletal problem can be treated with a Le Fort I osteotomy, followed by maxillary repositioning and stabilization with internal plate fixation in patients with permanent dentition.1 Maxillary distraction osteogenesis is indicated in severe angle class III malocclusions and severe maxillary hypoplasia among some cleft patients and those with other craniofacial deformities.2 Distraction osteogenesis has some advantages, such as easy advancement of the maxilla, being easy and safe for large advancements, and achieving stable results. During Le Fort I distraction osteogenesis, placement of the distractor in the correct position and then disconnecting it before the osteotomy is a difficult procedure and lengthens the operation time. A surgical guide placed on the anterior nasal spine (ANS) may be useful for carrying the correct position obtained on the 3D model to the patient’s maxilla. At the same time, it may simplify the technical difficulties and 0901-5027/060739 + 03 $36.00/0
may shorten the operation time. We present a transparent acrylic surgical guide placed on the ANS for these purposes in Le Fort I distraction osteogenesis. Technique
Planning of the operation was done on the patient’s 3D model and the distractors were chosen bilaterally for Le Fort I distraction. After marking the osteotomy line, the distractors were placed on the model and then the distractor plates were contoured to fit the model and fixed with screws. Next, the distractors were disconnected and the transparent acrylic surgical guide was prepared on the 3D model (Fig. 1). To prepare the surgical guide, self-curing acrylic resin was attached on both sides of the maxilla and oriented according to anatomical landmarks, such as the ANS. The position of the surgical guide was secured on the model according to reference points, such as the ANS and the contours of the lateral maxillary wall. The acrylic plate fitted tightly to the nasal spine like a mortise and tenon system
Key words: distraction osteogenesis; maxilla; surgical plate. Accepted for publication 9 January 2014 Available online 10 February 2014
(Fig. 2). After the surgical guide was fitted to the model, the screw holes of the distractor plates were marked and opened on the guide using a bur. During the operation, the planned position of the distractor was carried to the patient’s maxilla using the transparent acrylic guide and this was easily adapted to the patient’s maxilla with the previously created mortise and tenon system using the ANS. The screw holes that were marked on the acrylic guide were opened before the Le Fort I osteotomy. The osteotomy was performed after opening the holes; the maxillary distractor was then placed in the correct position very easily. After the activation phase of the distraction osteogenesis, planned vectors and directions could be achieved and hence the maxilla was located in the desired position (Fig. 3). Discussion
Several preoperative procedures are useful in the planning of distractor positioning and alignment. Computed tomography
Crown Copyright # 2014 Published by Elsevier Ltd on behalf of International Association of Oral and Maxillofacial Surgeons. All rights reserved.
740
Baykul et al.
Fig. 1. The acrylic plate fitted tightly to the nasal spine like a mortise and tenon system.
scans, dental models, cephalometric tracings, and 3D anatomical models are beneficial in determining the location of the osteotomy and placement of the distractor devices. 3D anatomical models have been used as successful hands-on tools for contouring the distractor plates, aligning the distractors, calibrating the desired vectors of distraction, and making the osteotomy prior to surgery. These advantages also reduce the operation time, and surgeons can determine the correct and accurate
Fig. 2. The acrylic surgical guide that had been prepared on the 3D model was placed on the model.
placement of the distractor in the model surgery before the operation. On the other hand, in the use of the 3D models, surgical guides may be prepared for carrying the correct position of the distractors from the 3D model to the patient’s maxilla, as presented here. Using a transparent acrylic surgical guide, it is possible to safely carry the contoured distractor plates, aligned distractors, and calibrated distraction vectors from the 3D model to the patient’s maxilla with the aid
of the screw holes marked on the guide. The use of a surgical template for transferring the distractor to the patient has been reported in several cases in the literature; the additional feature of the guide presented here is the use of the ANS as a guide during transfer in the operating room.3–6 The ANS may be used as a critical anatomical landmark for applying this type of surgical guide. By creating such a tenon–mortise system using the anatomical shape of the ANS, stabilization and adaptation of the surgical guide is very easy in such cases. During the operation, after drilling the bone with the use of the marked screw holes on the guide, the osteotomy may be performed and then the distractors may be fixed. At the same time, since placement of the distractor for positioning and then disconnecting it before the osteotomy is unnecessary, the use of such a guide may shorten the operation time, avoid the complications of general anaesthesia, and simplify the technique. Funding
None. Competing interests
None declared. Ethical approval
Not required.
Fig. 3. Planned vectors and directions could be achieved and so the maxilla was located in the desired position.
Patient consent
Not required.
Surgical acrylic guide for maxillary distractor References 1. Yamauchi K, Mitsugi M, Takahashi T. Maxillary distraction osteogenesis using Le Fort I osteotomy without intraoperative down-fracture. Int J Oral Maxillofac Surg 2006;35: 493–8. 2. Keßler P, Wiltfang J, Schultze-Mosgau S, Hirschfelder U, Neukam FW. Distraction osteogenesis of the maxilla and midface using a subcutaneous device: report of four cases. Br J Oral Maxillofac Surg 2001;39:13–21. 3. Iida S, Kogo M, Aikawa T, Masuda T, Yoshimura N, Adachi S. Maxillary distraction osteogenesis using the intraoral distractors
and the full-covered tooth-supported maxillary splint. J Oral Maxillofac Surg 2007;65: 813–7. 4. Herford AS. Use of a plate-guided distraction device for transport distraction osteogenesis of the mandible. J Oral Maxillofac Surg 2004;62:412–20. 5. Bae MJ, Kim JY, Park JT, Cha JY, Kim HJ, Yu HS, Hwang CJ. Accuracy of miniscrew surgical guides assessed from cone-beam computed tomography and digital models. Am J Orthod Dentofacial Orthop 2013;143: 893–901. 6. Kofod T, Pedersen TK, Nørholt SE, Jensen J. Stereolithographic models for simulation and
741
transfer of vector in vertical distraction of the mandibular ramus: a technical note. J Craniofac Surg 2005;16:608–14.
Address: Y. Fındık Department of Oral and Maxillofacial Surgery Faculty of Dentistry Su¨leyman Demirel University Isparta Turkey Tel: +90 246 2113251; Fax: +90 246 2370607 E-mail: [email protected]
