- Email: [email protected]
Results and complications of alveolar distraction osteogenesis to enhance vertical bone height
Results and complications of alveolar distraction osteogenesis to enhance vertical bone height Tayfun Günbay, DDS, PhD,a Banu Özveri Koyuncu, DDS, PhD,b M. Cemal Akay, DDS, PhD,b Aylin Sipahi, DDS, PhD,b and Ug˘ur Tekin, DDS, PhD,c Bornova, Turkey DEPARTMENT OF ORAL AND MAXILLOFACIAL SURGERY, FACULTY OF DENTISTRY, EGE UNIVERSITY
Objective. The aim of this retrospective study was to analyze the outcome and complications of alveolar distraction osteogenesis for the correction of vertically deficient ridges by using intraosseous and extraosseous distractors. Study design. Seven patients with severely atrophic alveolar crests were treated by distraction osteogenesis in 5 alveolar ridge deficiencies by intraosseous distractors and in 2 alveolar ridge deficiencies by extraosseous distractors. The bone deficiencies were secondary to atrophy after periodontal disease, tooth extraction, or trauma. Three months after consolidation of the distracted segments, implants were placed in the distracted areas. The average follow-up period after prosthetic loading was 50 months. Results. The mean alveolar height achieved was 7.8 mm (range, 4-9 mm). The intraoperative and postoperative problems encountered were lack of device activation (n ⫽ 1), lingual displacement of the distracted segment (n ⫽ 1), paresthesia of the lower lip (n ⫽ 4), and dehiscence and plate exposure (n ⫽ 2). Most of these complications were considered to be minor complications and were solved without any problems. Conclusion. It was concluded that alveolar distraction osteogenesis seems to be an effective technique to treat vertical alveolar ridge deficiencies, but adequate treatment planning is necessary for success. The complications related to this technique can be solved with simple treatments. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:e7-e13)
Dental rehabilitation of partially or totally edentulous patients with dental implants has become popular in the last decades with long-term results. Success rates for dental implants averages ⬎90%.1-5 However, vertical defect of the alveolar ridge may render the use of dental implants difficult or impossible owing to an insufficient bone volume. Various methods for alveolar ridge reconstruction exist, such as autogenous bone grafting,6-8 guided bone regeneration, and use of alloplastic materials.9,10 Alveolar distraction osteogenesis (ADO) was introduced by Chin and Toth in 199611 and has been applied as an alternative technique to the other surgical techniques.12 The method is widely used for increasing alveolar bone where rehabilitation with dental implants is required,13-15 and it makes the insertion of longer implants possible.16 Compared with the conventional techniques of bone grafting and guided bone regenerSupported by the Branch Directorate of Scientific Research Projects, University of Ege. a Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. b Senior assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. c Associate Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. Received for publication Sep 28, 2007; returned for revision Nov 27, 2007; accepted for publication Dec 14, 2007. 1079-2104/$ - see front matter © 2008 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.12.026
ation, ADO offers the advantages of decreased bone resorption, lower rate of infection and no donor site morbidity13,16,17 and gain of soft tissue.13,15,18 The disadvantages include difficulty in controlling the segments, lack of patient cooperation, the need for more office visits, and the cost of the device.19-21 In the present study, our experiences, including complications, with the Lead and Modus systems are presented, and advantages and disadvantages of these systems are discussed. MATERIAL AND METHODS Patients Seven systemically healthy patients, 6 women and 1 man, aged between 24 and 64 years, who presented with vertical alveolar ridge mandibular defects, were treated with ADO by 2 types of distractor devices: intraosseous (Lead System; Leibinger, Freiburg, Germany) and extraosseous (Modus Ars 1.5; Medartis, Basel, Switzerland) between February 2003 and June 2005. All of the patients signed an informed consent form. The type of distractor was chosen considering the location and length of the edentulous area. Two of the defects were in the premolar aspect of the mandible, 2 were in the anterior mandible, 1 in the anterior maxilla, 1 in the molar aspect of the mandible, and 1 in the premolar-molar mandible region. The deficiencies were caused by periodontal disease or atrophy after tooth extraction (n ⫽ 4), trauma (n ⫽ 2), or hypodontia (n ⫽ e7
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Table I. Features of the patients and type and number of distractors Case no.
Age
Gender
Distraction zone
Type of distractor
Etiologic factor
No. of distractors
1 2 3 4 5 6 7
38 26 30 64 24 53 48
M F F F F F F
Mandibula premolar Mandibula premolar Maxilla anterior Mandibula anterior Mandibula premolar-molar Mandibula molar Mandibula anterior
Lead System Lead System Lead System Modus Lead System Lead System Modus
Gun shot Hypodontia Traffic accident Edentulous Alveolar resorption Alveolar resorption Edentulous
1 1 2 1 1 1 1
l). One rod was placed in 3 patients and 2 rods in 1 patient with wide defects who were treated with intraosseous distractors (Lead System) (Table I). When 2 rods were used, they were positioned as parallel as possible. Routine radiographic documentation of the treated patients was obtained with panoramic and intraoral radiographs taken preoperatively, immediately after the application of the distractor, at the end of the distraction procedure, at the time of implant placement, at the time of prosthetic rehabilitation, and annually thereafter. Clinical examinations concerning the dental implants included periimplantitis, implant mobility, and gingival condition. Two cases, one in the maxilla and one in the mandible, are presented in Figs. 1 and 2. Surgical technique All the operations were performed under local anesthesia. A crestal incision was made along the alveolar ridge. A buccal mucoperiosteal flap elevation was performed exposing the lateral cortex, maintaining the attachment of the lingual mucoperiosteum to the transport segment. The lateral vertical bone cuts were made in an angulated manner to achieve a trapezoid-shaped bone segment. Then a horizontal osteotomy was performed, leaving a minimum 4 mm of bone preserved for the maintenance of sufficient blood circulation in the later alveolar bone segment. Before the mobilization of the transported segment, a 2 mm hole was drilled through the crestal mucosa and bone for placement of the lead screw (thread-distracted rod). Mobilization of the bone segment was achieved using fine chisels. The transport plate was fixed by fixation screws onto the transported bone, into which the threaded rod was introduced, and a base plate was fixed by fixation screws to the base of alveolar bone. After testing that the device was functioning properly, the osteotomy segment was returned as close as possible to its original position. The mucoperiosteal flap was closed primarily with 3.0 Vicryl sutures (Johnson & Johnson Intl., Somerville, NJ). For extraosseous devices, the surgical procedure was identical. All patients received 600 mg clindamycin per day, continuing for 7 days, and nonsteroidal analgesics.
Postoperative instructions for the patients included soft diet and oral hygiene with 0.2% chlorohexidine mouthrinse. Sutures were removed 7 days after surgery. The distraction protocol involved a latency period of 7 days. After this time period, activation of distraction devices was started at a rate of 0.8 mm twice daily by Lead System and 1 mm twice daily by Modus. After the augmentation of desired transport was obtained, the device was left in place for approximately 6-8 weeks to stabilize the segment. The prosthetic restoration of implants was performed after 3-4 months of osseointegration. A total of 14 endoosseous implants were placed. During clinical follow-up, distractor mobility, situation of distracted segment, and function of nervus alveolaris inferior were examined once a week. Clinical and radiologic follow-up periods were 6-56 months. RESULTS Vertical distraction osteogenesis was performed in 7 patients in the study, 5 using Lead System and 2 using Modus. The gained distance was evident clinically and radiographically. The mean vertical formation achieved in the patients was 7.8 mm (Table II). All of the patients tolerated the operations well except one. That patient felt severe pain during the distraction period. Therefore we reduced the distraction rate (0.25 mm), which relieved the discomfort. There was no clinical evidence of infection during the distraction period and consolidation period in any of the patients. Incorrect vector of the distracted segment occurred in 1 patient, but sufficient bone was gained. In that patient the displaced segment was repositioned with orthodontic device. In 4 patients, postoperative paresthesias of the mental nerve was noted which resolved after 8 weeks with vitamin B treatment. Fracture of a fixation screw occured in 1 case. Dehiscence and plate exposure were observed in 1 case but did not affect the functional or esthetic results. We recommended daily rinsing of the area with chlorohexidine mouthrinse for the treatment. The complications and the treatments are summarized in Table III. These minor complications were treated and did not
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Fig. 1. A, Panoramic radiograph of 30-year-old patient after mandibular fracture and traumatic avulsion of the anterior teeth and alveolar bone. B, Placement of the alveolar distractor during surgery. C, Panoramic radiograph after lengthening of the alveolar bone. D, After removal of the device and 4 implant placements. E, Panoramic radiograph 3.5 years after final prosthetic rehabilitation.
have an influence on the outcome of distraction. Dental implants were successfully inserted. We observed immature bone in 1 case during the removal of the distractor device. Therefore, we delayed insertion of the endoosseous implants for 2 months. In case 1, gunshot defect was repaired by distraction osteogenesis, but mucosal scar tissues prevented activation of distractor and required vertical augmentation with sandwich osteotomy technique. Implant insertion was not possible in case 4 because of the patient’s financial problems. Complete denture was applied to that patient. In the radiologic follow-up, no severe resorption in
the periimplant region was observed. Implants were loaded prosthetically in 7 patients with a mean follow-up after loading of 50 months (range 6-56 months). None of the implants were lost. DISCUSSION Vertical alveolar distraction osteogenesis method demonstrates many advantages in treating vertical alveolar bone defects compared with conventional methods from the aspect of bone quality, bone quantity, donor site morbidity, and decreased bone resorption. The main advantage of the vertical alveolar bone distraction is that there is an increase in alveolar bone
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Fig. 2. A, Panoramic radiograph of 48-year-old patient with severely resorbed mandible. B, Intraoral photograph showing mandibular atrophy. C, Segmental alveolar osteotomy of the anterior region with extraosseous alveolar distractor. D, Postdistraction panoramic radiograph showed lengthening of the alveolar bone. E, Panoramic radiograph 1.5 years after final prosthetic rehabilitation.
height with new bone formation beneath the distracted bone. Furthermore, simultaneous lengthening of the surrounding soft tissues is achieved by histiogenesis.19,22,23 New bone regeneration was performed in the distraction gap supporting the transported bone. This is important to achieve better implant anchorage and esthetically functional prosthetic reconstruction.
Distraction osteogenesis can be achieved by intraosseous24,25 or extraosseous devices.26 Distraction osteogenesis with intraoral extraosseous distractors of a single tooth space may in fact be more difficult to perform, owing to the limited space available for osteotomies and the dimensions of the distraction device. In the present study, we used the Lead System as an intraosseous distractor. It is especially used at the pos-
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Table II. Gained bone amount, transport width, number of implants, and type of prosthesis in the distracted area Case no.
Distraction (mm)
Transport wıdth
No. of implants
Type of prosthesis
1 2 3 4 5 6 7
4 9 8 9 9 8 8
23 13 42 34 25 29 15
— 3 4 — 3 2 2
Precision attachment Fixed partial denture Fixed partial denture Complete denture Fixed partial denture Fixed partial denture Ball attachment
terior regions of the mandible with limited spaces when opposing teeth were available. When compared with extraosseous devices, whose main components are placed on the surface of the bone, intraosseous devices have several advantages, including the capability of distracting very small bone segments, not requiring any pins or plates to hold the distractor in place, and being a better tolerated device by the patients because of their small dimensions.17,27 However, we can no longer agree with the last claim, because we observed that our patients tolerated both types of the distractors. Some authors do not recommend a temporary denture to overlie the alveolus to prevent relapse in the final alveolar height during the period of lengthening and even in the period of consolidation, because regenerated bone is not mature enough.16 In our cases, we also did not advise temporary dentures. In one case, we noted immature bone in the mandible during the removal of the distractor device, and we postponed insertion of the endoosseous implants for 2 months. Clinical and experimental reports have shown that ADO is effective for treating severe forms of alveolar ridge atrophy12,13,18,23,28 and is a reliable technique for the correction of vertically deficient edentulous ridges,26 but some intra- and postoperative complications can occur.19,29-31 The complications have been reported as fracture of the mandible, fracture of the transport segment, difficulties in finishing the osteotomy on the lingual side, excessive length of the threaded rod, incorrect direction of distraction, perforation of the mucosa by the transport segment, suture dehiscence, and bone formation defects. Fracture or resorption of the alveolar transported segment may occur as a complication; care should be taken not to make it too small, but at least 5 mm in height.15,16 Another reason for the resorption of the transported segment is inadequate spongiosa bone, so horizontal osteotomy must be widened as much as possible.32 However, it must be kept in mind that if the remaining bone becomes too thin, the risk of mandibular fracture and nerve damage will also increase.16
Alveolar distraction should be avoided in a very atrophic mandible, where a complete bone fracture may occur. Fracture of the mandible is the most severe complication encountered.26,29,30 In the present study, patients whose mandibular bone was at least 9-10 mm vertically were for these reasons preferred. Fracture of the transport segment and mandible during surgery was not observed. Difficulties were encountered in completing the osteotomy on the lingual side, which we had to access from the labial vestibular side. To do this, some authors have constructed fine chisels from cement spatulas which were carefully introduced from the vestibular side, checking their exit from the lingual side with a finger to avoid damage to the lingual mucoperiosteum or the floor of the mouth, but the ultrasonic osteotome has proven to be much more comfortable, without the risk of damage to the vascular plexa of the floor of the mouth.19 A common problem with the Lead System is the difficulty of controlling the direction of the device to keep the vector straight.16,19,24 Inappropriate direction of distraction may be caused by any of several factors, including resistance of the soft tissue on the lingual/palatal side of the muscles and intact periosteum.19 The distractor will tend to lean to the lingual side, requiring postoperative repositioning. Careful preoperative planning is essential to ensure good vectorization.33 Repositioning of a displaced transport segment is generally performed using orthodontic appliance arch wires.16-20,34 In 1 patient the displaced segment was repositioned with orthodontic device. It has been reported that extraosseous distractors maintained much more stabilization at basal and transport segments than intraosseous distractors.35 In the present study, we did not notice malposition of the transported segments at extraosseous distractors. We think that malposition and stabilization problems that were seen in intraosseous distractor were related to lack of stabilization in that type of distractor. When the transport segment is relatively long (more than about 2 cm), it may be difficult to achieve accurately controlled osteogenesis using a single distractor. The use of 2 distractors, one at each end of the transport segment, resolves this problem.19,20,24,36 For this reason, we applied 2 distractors in a wide maxillary defect in case 3. Temporary paresthesias showed spontaneous resolution within 6-8 weeks with conservative treatment, similar to other studies,31,37 in our 4 patients. The use of an ultrasonic osteotome might decrease the risk of nerve damage during osteotomy preparation.31 The activation period of the distraction device is usually pain-free38; however, we noted tension-related pain in 1 patient because of more than 1 cm of alveolar distraction. The pain disappeared when the rate of
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Table III. Minor and major complications in alveolar distraction osteogenesis with necessary treatments Case no.
Major complications
Minor complications
Treatment
1 2
Lack of device activation —
3 4
— —
5 6
— —
7
—
Paresthesia of the nerve Incorrect vector of the transport segment Dehiscence and plate exposure Paresthesia of the nerve — Dehiscence and plate exposure Severe pain Paresthesia of the nerve — Immature bone at time of removal of distractor Paresthesia of the nerve Fracture of screw
Local Repositioned with orthodontic devices Local Local — Local Reduction of distraction rate Local — Delay of insertion of implants by 2 months Local None
distraction was reduced to 0.25 mm/24 h. It is suggested to increase the frequency of elevation without changing the daily rate.37 Parallel or convergent lateral osteotomies during activation may result, with discomfort, friction, and possible compromise of the final outcome. Applying lateral osteotomies divergent to one another during surgery is recommended.26 We made trapezoidal osteotomies in operations for facilitation of the transport segment movement. Saulacic et al.31 mentioned that the varying amount of distraction performed in patients reporting pain in their clinical study indicated that the occurrence might be subjective. We agree with these authors, because the statement of our patient about pain may be doubtful. Soft tissue dehiscence was the most common minor complication (37.8% of distraction sites) with 6.7% of these becoming infected in a recent study. One of the causes for this may well be the distraction rate of 0.9 mm per day.30 Dehiscence and plate exposure were found in 2 of the present cases, but did not affect the functional or esthetic results. We recommended daily rinsing of the area with chlorohexidine mouthrinse for treatment. In other published studies, the prevalence of complications that compromised the final outcome is 2.7% to 20%.18,26,30,38 It was concluded in a clinical study that ADO is an effective technique to treat vertical alveolar ridge deficiencies.29 Most complications related to surgery can be avoided with adequate treatment planning.26 In other clinical studies the authors reported that most of the minor complications could be readily resolved by the use of appropriate procedures, but very close follow-up is required.19,20,29 Vertical alveolar distraction osteogenesis is not an uncomplicated procedure; however, long-term survival of dental implants inserted into distracted areas is satisfactory.30 On the other hand, Enislidis et al.39 reported that the use of subperiosteal devices for vertical augmentation of edentulous mandibles is hazardous and offers no advantage over other surgical methods and that all of the patients had severe complications. Fukuda et
al.40 also stated that vertical distraction osteogenesis for implant placement appeared to have serious risks and complications in reconstructed bone. We have not observed serious complications, such as fracture of the mandible, fracture of the transport segment, infection, or breakage of the distraction device in our study. Among the major complications, in 1 patient mucosal scar tissues prevented activation of alveolar distractor. We recommend using ADO technique in atrophic crests including scar tissues carefully. In conclusion, ADO is an effective technique to treat vertical alveolar ridge deficiencies. The intraosseous distractors can be used for distraction of small bone segments because of their small dimensions, but difficulty of vector control is the disadvantage of the Lead System. Modus maintained much more stabilization at basal and transport segments than intraosseous distractors. Alveolar distraction osteogenesis seems to be valid for simultaneous reconstruction of the alveolar bone but adequate treatment plannig is necessary for the success. Complications of this technique can be solved with simple treatments. REFERENCES 1. Adell R, Eriksson B, Lekholm U, Brånemark PI, Jemt T. A long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws. Int J Oral Maxillofac Implants 1990;5:347-59. 2. Albrektsson T, Bergman B, Folmer T, Henry P, Higuchi K, Klinenberg I, et al. A multicenter study of osseointegrated oral implants. J Prosthet Dent 1988;60:75-84. 3. Albrektsson T, Zarb G, Worthington P, Eriksson AR. The longterm efficacy of currently used dental implants: a review and proposed criteria of success. Int J Oral Maxillofac Implants 1986;1:1-25. 4. Buser D, Mericske-Stern R, Bernard JP, Behneke A, Behneke N, Hirt HP, et al. Long-term evaluation of nonsumerged ITI implants. Part I: 8-year life table analysis of a prospective multicenter study with 2359 implants. Clin Oral Implants Res 1997;8:161-72. 5. Lekholm U, Gunne J, Henry P, Higuchi K, Linden U, Bergström, et al. Survival of the Branemark implant in partially edentulous
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6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
jaws. A 10-year prospective multicenter study. Int J Oral Maxillofac Implants 1999;14:639-45. Nyström EK, Kahnberg K-E, Gunne J. Bone grafts and Branemark implants in the treatment of severely resorbed maxilla: a two-year longitudinal study. Int J Oral Maxillofac Implants 1993;8:45-53. Satow S, Slagter AP, Stoelinga PJW, Habets LLMH. Interposed bone grafts to accommodate endosteal implants for retaining mandibular overdentures. A 1-7 year follow-up study. Int J Oral Maxillofac Surg 1997;26:358-64. Triplett RG, Schow SR. Autologous bone grafts and endosseous implants: complementary techniques. J Oral Maxillofac Surg 1996;54:489-94. Caplanis N, Sigurdsson TJ, Rohrer MD, Wikesjö UME. Effect of allogeneic, freeze-dried, demineralized bone matrixon guided bone regeneration in supraalveolar peri-implant defects in dogs. Int J Oral Maxillofac Implants 1997;12:634-42. Jensen OT, Greer RO JR, Johnson L, Kassebaum D. Vertical guided bone-graft augmentation in a new canine mandibular model. Int J Oral Maxillofac Implants 1995;10:335-44. Chin M, Toth B. Distraction osteogenesis in maxillofacial surgery using internal devices: review of five cases. J Oral Maxillofac Surg 1996;54:45-53. Hwang SJ, Jung JG, Jung JJ, Kyung SH. Vertical alveolar bone distraction at molar region using lag screw principle. J Oral Maxillofac Surg 2004;62:787-94. Horiuchi K, Uchida H, Yamamoto K, Hatano N. Anteroinferior distraction of the atrophic subtotal maxillary alveolus for implant placement: a case report. Int J Oral Maxillofac Implants 2002; 17:416-23. Maurette O’Brien PE, Allais De Maurette ME, Mazzonetto R. Distracción osteogénica alveolar: una alternativa en la reconstrucción de rebordes alveolares atróficos. Descripción de 10 casos. Rev Esp Cirug Oral Maxilofac 2004;26:41-7. Raghoebar GM, Heydenrijk K, Vissink A. Vertical distraction of the severely resorbed mandible. The Groningen distraction device. Int J Oral Maxillofac Surg 2000;29:416-20. Rachmiel A, Srouji S, Peled M. Alveolar ridge augmentation by distraction osteogenesis. Int J Oral Maxillofac Surg 2001;30: 510-17. Urbani G. Alveolar distraction before implantation: a report of five cases and a review of the literature. Int J Periodontics Restorative Dent 2001;21:569-79. Jensen OT, Cockrell R, Kuhike L, Reed C. Anterior maxillary alveolar distraction osteogenesis: a prospective 5-year clinical study. Int J Oral Maxillofac Implants 2002;17:52-68. Garcia-Garcia A, Martin-Somoza M, Gandara-Vila P, Meceiras JL. Minor complications arising in alveolar distraction osteogenesis. J Oral Maxillofac Surg 2002;60:496 – 01. Uckan S, Haydar SG, Dolanmaz D. Alveolar distraction: analysis of 10 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:561-5. Van Strijen PJ, Breuning KH, Becking AG, Perdijk FBT, Tuinzing DB. Complications in bilateral mandibular distraction osteogenesis using internal devices. Oral Surg Oral Med Oral Pathol Oral Radiolo Endod 2003;96:392-7. Chiapasco M, Romeo E, Vogel G. Vertical distraction osteogenesis of edentulous ridges for improvement of oral implant positioning: A clinical report of preliminary results. Int J Oral Maxillofac Implants 2001;16:43-51. Gaggl A, Schultes G, Regauer S, Kärcher H. Healing process after alveolar ridge distraction in sheep. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:420-9. Gaggl A, Schultes G, Karcher H. Distraction implants: a new
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25.
26.
27.
28.
29.
30.
31.
32.
33. 34.
35. 36.
37.
38.
39.
40.
operative technique for alveolar ridge augmentation. J Craniomaxillofac Surg 1999;2:214-21. Garcia-Garcia A, Somoza-Martin M, Gandara-Vila P, Saulacic N, Gandara-Rey M. Alveolar distraction before insertion of dental implants in the posterior mandible. Br J Oral Maxillofac Surg 2003;41:376-9. Chiapasco M, Consolo U, Bianchi A, Ronchi P. Alveolar distraction osteogenesis for the correction of vertically deficient edentulous ridges: a multicenter prospective study on humans. Int J Oral Maxillofac Implants 2004;19:399 – 07. Yalcin S, Ordulu M, Emes Y, Gur H, Aktas I, Caniklioglu C. Alveolar distraction osteogenesis before placement of dental ımplants. Implant Dent 2006;15:48-52. Erkut S, Uckan S. Alveolar distraction osteogenesis and implant placement in a severely resorbed maxilla: a clinical report. J Prosthet Dent 2006;95:340-3. Mazzonetto R, Allais M, Maurette PE, Moreira RWF. A retrospective study of the potential complications during alveolar distraction osteogenesis in 55 patients. Int J Oral Maxillofacial Surg 2007;36:6-10. Enislidis G, Fock N, Millesi-Schobel G, Klug C, Wittwer G, Kaan Yerit, et al. Analysis of complications following alveolar distraction osteogenesis and implant placement in the partially edentulous mandible. Oral Surg Oral Med Oral Pathol Oral Radiolo Endod 2005;100:25-30. Saulacic N, Martín MS, Camacho MAL and García García A. Complications in alveolar distraction osteogenesis: a clinical investigation. J Oral Maxillofac Surg 2007;65:267-74. Uckan S, Dolanmaz D, Kalayci A, Cilasun U. Distraction osteogenesis of basal mandibular bone for reconstruction of the alveolar ridge. Br J Oral Maxillofacial Surg 2002;40:393-6. Mattick CR. Osteogenic distraction within the craniofacial complex. Dent Update 2000;27:426-31. Baker B, Gibbons S, Woods M. Intra-alveolar distraction osteogenesis in preparation for dental implant placement combined with orthodontic/orthognathic surgical treatment: a case report. Aust Dent J 2003;48:65-8. Walker DA. Mandibular distraction osteogenesis for endoosseous dental implants. J Can Dent Assoc 2005;71:171-5. Garcia AG, Martin MS, Vila PG, Maceiras JL. Alveolar ridge osteogenesis using 2 intraosseous distractors: Uniform and nonuniform distraction. J Oral Maxillofac Surg 2002;60:1510-2. Gaggl A, Schultes G, Karcher H. Vertical alveolar ridge distraction with prosthetic treatable distractors: a clinical investigation. Int J Oral Maxillofac Implants 2000;15:701-10. Kunkel M, Wahlmann U, Reichert TE, Wegener J, Wagner W. Reconstruction of mandibular defects following tumor ablation by vertical distraction osteogenesis using intraosseous distraction devices. Clin Oral Implants Res 2005;16:89-97. Enislidis G, Fock N, Ewers R. Distraction osteogenesis with subperiosteal devices in edentulous mandibles. Br J Oral Maxillofac Surg 2005;43:399 – 03. Fukuda M, Iino M, Ohnuki T, Nagai H, Takahashi T. Vertical alveolar distraction osteogenesis with complications in a reconstructed mandible. J Oral Implantol 2003;29:185-8.
Reprint requests: Dr. Banu Özveri Koyuncu Department of Oral and Maxillofacial Surgery Ege University Bornova Turkey [email protected]
Objective. The aim of this retrospective study was to analyze the outcome and complications of alveolar distraction osteogenesis for the correction of vertically deficient ridges by using intraosseous and extraosseous distractors. Study design. Seven patients with severely atrophic alveolar crests were treated by distraction osteogenesis in 5 alveolar ridge deficiencies by intraosseous distractors and in 2 alveolar ridge deficiencies by extraosseous distractors. The bone deficiencies were secondary to atrophy after periodontal disease, tooth extraction, or trauma. Three months after consolidation of the distracted segments, implants were placed in the distracted areas. The average follow-up period after prosthetic loading was 50 months. Results. The mean alveolar height achieved was 7.8 mm (range, 4-9 mm). The intraoperative and postoperative problems encountered were lack of device activation (n ⫽ 1), lingual displacement of the distracted segment (n ⫽ 1), paresthesia of the lower lip (n ⫽ 4), and dehiscence and plate exposure (n ⫽ 2). Most of these complications were considered to be minor complications and were solved without any problems. Conclusion. It was concluded that alveolar distraction osteogenesis seems to be an effective technique to treat vertical alveolar ridge deficiencies, but adequate treatment planning is necessary for success. The complications related to this technique can be solved with simple treatments. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2008;105:e7-e13)
Dental rehabilitation of partially or totally edentulous patients with dental implants has become popular in the last decades with long-term results. Success rates for dental implants averages ⬎90%.1-5 However, vertical defect of the alveolar ridge may render the use of dental implants difficult or impossible owing to an insufficient bone volume. Various methods for alveolar ridge reconstruction exist, such as autogenous bone grafting,6-8 guided bone regeneration, and use of alloplastic materials.9,10 Alveolar distraction osteogenesis (ADO) was introduced by Chin and Toth in 199611 and has been applied as an alternative technique to the other surgical techniques.12 The method is widely used for increasing alveolar bone where rehabilitation with dental implants is required,13-15 and it makes the insertion of longer implants possible.16 Compared with the conventional techniques of bone grafting and guided bone regenerSupported by the Branch Directorate of Scientific Research Projects, University of Ege. a Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. b Senior assistant, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. c Associate Professor, Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Ege University, Bornova, Turkey. Received for publication Sep 28, 2007; returned for revision Nov 27, 2007; accepted for publication Dec 14, 2007. 1079-2104/$ - see front matter © 2008 Mosby, Inc. All rights reserved. doi:10.1016/j.tripleo.2007.12.026
ation, ADO offers the advantages of decreased bone resorption, lower rate of infection and no donor site morbidity13,16,17 and gain of soft tissue.13,15,18 The disadvantages include difficulty in controlling the segments, lack of patient cooperation, the need for more office visits, and the cost of the device.19-21 In the present study, our experiences, including complications, with the Lead and Modus systems are presented, and advantages and disadvantages of these systems are discussed. MATERIAL AND METHODS Patients Seven systemically healthy patients, 6 women and 1 man, aged between 24 and 64 years, who presented with vertical alveolar ridge mandibular defects, were treated with ADO by 2 types of distractor devices: intraosseous (Lead System; Leibinger, Freiburg, Germany) and extraosseous (Modus Ars 1.5; Medartis, Basel, Switzerland) between February 2003 and June 2005. All of the patients signed an informed consent form. The type of distractor was chosen considering the location and length of the edentulous area. Two of the defects were in the premolar aspect of the mandible, 2 were in the anterior mandible, 1 in the anterior maxilla, 1 in the molar aspect of the mandible, and 1 in the premolar-molar mandible region. The deficiencies were caused by periodontal disease or atrophy after tooth extraction (n ⫽ 4), trauma (n ⫽ 2), or hypodontia (n ⫽ e7
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Table I. Features of the patients and type and number of distractors Case no.
Age
Gender
Distraction zone
Type of distractor
Etiologic factor
No. of distractors
1 2 3 4 5 6 7
38 26 30 64 24 53 48
M F F F F F F
Mandibula premolar Mandibula premolar Maxilla anterior Mandibula anterior Mandibula premolar-molar Mandibula molar Mandibula anterior
Lead System Lead System Lead System Modus Lead System Lead System Modus
Gun shot Hypodontia Traffic accident Edentulous Alveolar resorption Alveolar resorption Edentulous
1 1 2 1 1 1 1
l). One rod was placed in 3 patients and 2 rods in 1 patient with wide defects who were treated with intraosseous distractors (Lead System) (Table I). When 2 rods were used, they were positioned as parallel as possible. Routine radiographic documentation of the treated patients was obtained with panoramic and intraoral radiographs taken preoperatively, immediately after the application of the distractor, at the end of the distraction procedure, at the time of implant placement, at the time of prosthetic rehabilitation, and annually thereafter. Clinical examinations concerning the dental implants included periimplantitis, implant mobility, and gingival condition. Two cases, one in the maxilla and one in the mandible, are presented in Figs. 1 and 2. Surgical technique All the operations were performed under local anesthesia. A crestal incision was made along the alveolar ridge. A buccal mucoperiosteal flap elevation was performed exposing the lateral cortex, maintaining the attachment of the lingual mucoperiosteum to the transport segment. The lateral vertical bone cuts were made in an angulated manner to achieve a trapezoid-shaped bone segment. Then a horizontal osteotomy was performed, leaving a minimum 4 mm of bone preserved for the maintenance of sufficient blood circulation in the later alveolar bone segment. Before the mobilization of the transported segment, a 2 mm hole was drilled through the crestal mucosa and bone for placement of the lead screw (thread-distracted rod). Mobilization of the bone segment was achieved using fine chisels. The transport plate was fixed by fixation screws onto the transported bone, into which the threaded rod was introduced, and a base plate was fixed by fixation screws to the base of alveolar bone. After testing that the device was functioning properly, the osteotomy segment was returned as close as possible to its original position. The mucoperiosteal flap was closed primarily with 3.0 Vicryl sutures (Johnson & Johnson Intl., Somerville, NJ). For extraosseous devices, the surgical procedure was identical. All patients received 600 mg clindamycin per day, continuing for 7 days, and nonsteroidal analgesics.
Postoperative instructions for the patients included soft diet and oral hygiene with 0.2% chlorohexidine mouthrinse. Sutures were removed 7 days after surgery. The distraction protocol involved a latency period of 7 days. After this time period, activation of distraction devices was started at a rate of 0.8 mm twice daily by Lead System and 1 mm twice daily by Modus. After the augmentation of desired transport was obtained, the device was left in place for approximately 6-8 weeks to stabilize the segment. The prosthetic restoration of implants was performed after 3-4 months of osseointegration. A total of 14 endoosseous implants were placed. During clinical follow-up, distractor mobility, situation of distracted segment, and function of nervus alveolaris inferior were examined once a week. Clinical and radiologic follow-up periods were 6-56 months. RESULTS Vertical distraction osteogenesis was performed in 7 patients in the study, 5 using Lead System and 2 using Modus. The gained distance was evident clinically and radiographically. The mean vertical formation achieved in the patients was 7.8 mm (Table II). All of the patients tolerated the operations well except one. That patient felt severe pain during the distraction period. Therefore we reduced the distraction rate (0.25 mm), which relieved the discomfort. There was no clinical evidence of infection during the distraction period and consolidation period in any of the patients. Incorrect vector of the distracted segment occurred in 1 patient, but sufficient bone was gained. In that patient the displaced segment was repositioned with orthodontic device. In 4 patients, postoperative paresthesias of the mental nerve was noted which resolved after 8 weeks with vitamin B treatment. Fracture of a fixation screw occured in 1 case. Dehiscence and plate exposure were observed in 1 case but did not affect the functional or esthetic results. We recommended daily rinsing of the area with chlorohexidine mouthrinse for the treatment. The complications and the treatments are summarized in Table III. These minor complications were treated and did not
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Fig. 1. A, Panoramic radiograph of 30-year-old patient after mandibular fracture and traumatic avulsion of the anterior teeth and alveolar bone. B, Placement of the alveolar distractor during surgery. C, Panoramic radiograph after lengthening of the alveolar bone. D, After removal of the device and 4 implant placements. E, Panoramic radiograph 3.5 years after final prosthetic rehabilitation.
have an influence on the outcome of distraction. Dental implants were successfully inserted. We observed immature bone in 1 case during the removal of the distractor device. Therefore, we delayed insertion of the endoosseous implants for 2 months. In case 1, gunshot defect was repaired by distraction osteogenesis, but mucosal scar tissues prevented activation of distractor and required vertical augmentation with sandwich osteotomy technique. Implant insertion was not possible in case 4 because of the patient’s financial problems. Complete denture was applied to that patient. In the radiologic follow-up, no severe resorption in
the periimplant region was observed. Implants were loaded prosthetically in 7 patients with a mean follow-up after loading of 50 months (range 6-56 months). None of the implants were lost. DISCUSSION Vertical alveolar distraction osteogenesis method demonstrates many advantages in treating vertical alveolar bone defects compared with conventional methods from the aspect of bone quality, bone quantity, donor site morbidity, and decreased bone resorption. The main advantage of the vertical alveolar bone distraction is that there is an increase in alveolar bone
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Fig. 2. A, Panoramic radiograph of 48-year-old patient with severely resorbed mandible. B, Intraoral photograph showing mandibular atrophy. C, Segmental alveolar osteotomy of the anterior region with extraosseous alveolar distractor. D, Postdistraction panoramic radiograph showed lengthening of the alveolar bone. E, Panoramic radiograph 1.5 years after final prosthetic rehabilitation.
height with new bone formation beneath the distracted bone. Furthermore, simultaneous lengthening of the surrounding soft tissues is achieved by histiogenesis.19,22,23 New bone regeneration was performed in the distraction gap supporting the transported bone. This is important to achieve better implant anchorage and esthetically functional prosthetic reconstruction.
Distraction osteogenesis can be achieved by intraosseous24,25 or extraosseous devices.26 Distraction osteogenesis with intraoral extraosseous distractors of a single tooth space may in fact be more difficult to perform, owing to the limited space available for osteotomies and the dimensions of the distraction device. In the present study, we used the Lead System as an intraosseous distractor. It is especially used at the pos-
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Table II. Gained bone amount, transport width, number of implants, and type of prosthesis in the distracted area Case no.
Distraction (mm)
Transport wıdth
No. of implants
Type of prosthesis
1 2 3 4 5 6 7
4 9 8 9 9 8 8
23 13 42 34 25 29 15
— 3 4 — 3 2 2
Precision attachment Fixed partial denture Fixed partial denture Complete denture Fixed partial denture Fixed partial denture Ball attachment
terior regions of the mandible with limited spaces when opposing teeth were available. When compared with extraosseous devices, whose main components are placed on the surface of the bone, intraosseous devices have several advantages, including the capability of distracting very small bone segments, not requiring any pins or plates to hold the distractor in place, and being a better tolerated device by the patients because of their small dimensions.17,27 However, we can no longer agree with the last claim, because we observed that our patients tolerated both types of the distractors. Some authors do not recommend a temporary denture to overlie the alveolus to prevent relapse in the final alveolar height during the period of lengthening and even in the period of consolidation, because regenerated bone is not mature enough.16 In our cases, we also did not advise temporary dentures. In one case, we noted immature bone in the mandible during the removal of the distractor device, and we postponed insertion of the endoosseous implants for 2 months. Clinical and experimental reports have shown that ADO is effective for treating severe forms of alveolar ridge atrophy12,13,18,23,28 and is a reliable technique for the correction of vertically deficient edentulous ridges,26 but some intra- and postoperative complications can occur.19,29-31 The complications have been reported as fracture of the mandible, fracture of the transport segment, difficulties in finishing the osteotomy on the lingual side, excessive length of the threaded rod, incorrect direction of distraction, perforation of the mucosa by the transport segment, suture dehiscence, and bone formation defects. Fracture or resorption of the alveolar transported segment may occur as a complication; care should be taken not to make it too small, but at least 5 mm in height.15,16 Another reason for the resorption of the transported segment is inadequate spongiosa bone, so horizontal osteotomy must be widened as much as possible.32 However, it must be kept in mind that if the remaining bone becomes too thin, the risk of mandibular fracture and nerve damage will also increase.16
Alveolar distraction should be avoided in a very atrophic mandible, where a complete bone fracture may occur. Fracture of the mandible is the most severe complication encountered.26,29,30 In the present study, patients whose mandibular bone was at least 9-10 mm vertically were for these reasons preferred. Fracture of the transport segment and mandible during surgery was not observed. Difficulties were encountered in completing the osteotomy on the lingual side, which we had to access from the labial vestibular side. To do this, some authors have constructed fine chisels from cement spatulas which were carefully introduced from the vestibular side, checking their exit from the lingual side with a finger to avoid damage to the lingual mucoperiosteum or the floor of the mouth, but the ultrasonic osteotome has proven to be much more comfortable, without the risk of damage to the vascular plexa of the floor of the mouth.19 A common problem with the Lead System is the difficulty of controlling the direction of the device to keep the vector straight.16,19,24 Inappropriate direction of distraction may be caused by any of several factors, including resistance of the soft tissue on the lingual/palatal side of the muscles and intact periosteum.19 The distractor will tend to lean to the lingual side, requiring postoperative repositioning. Careful preoperative planning is essential to ensure good vectorization.33 Repositioning of a displaced transport segment is generally performed using orthodontic appliance arch wires.16-20,34 In 1 patient the displaced segment was repositioned with orthodontic device. It has been reported that extraosseous distractors maintained much more stabilization at basal and transport segments than intraosseous distractors.35 In the present study, we did not notice malposition of the transported segments at extraosseous distractors. We think that malposition and stabilization problems that were seen in intraosseous distractor were related to lack of stabilization in that type of distractor. When the transport segment is relatively long (more than about 2 cm), it may be difficult to achieve accurately controlled osteogenesis using a single distractor. The use of 2 distractors, one at each end of the transport segment, resolves this problem.19,20,24,36 For this reason, we applied 2 distractors in a wide maxillary defect in case 3. Temporary paresthesias showed spontaneous resolution within 6-8 weeks with conservative treatment, similar to other studies,31,37 in our 4 patients. The use of an ultrasonic osteotome might decrease the risk of nerve damage during osteotomy preparation.31 The activation period of the distraction device is usually pain-free38; however, we noted tension-related pain in 1 patient because of more than 1 cm of alveolar distraction. The pain disappeared when the rate of
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Table III. Minor and major complications in alveolar distraction osteogenesis with necessary treatments Case no.
Major complications
Minor complications
Treatment
1 2
Lack of device activation —
3 4
— —
5 6
— —
7
—
Paresthesia of the nerve Incorrect vector of the transport segment Dehiscence and plate exposure Paresthesia of the nerve — Dehiscence and plate exposure Severe pain Paresthesia of the nerve — Immature bone at time of removal of distractor Paresthesia of the nerve Fracture of screw
Local Repositioned with orthodontic devices Local Local — Local Reduction of distraction rate Local — Delay of insertion of implants by 2 months Local None
distraction was reduced to 0.25 mm/24 h. It is suggested to increase the frequency of elevation without changing the daily rate.37 Parallel or convergent lateral osteotomies during activation may result, with discomfort, friction, and possible compromise of the final outcome. Applying lateral osteotomies divergent to one another during surgery is recommended.26 We made trapezoidal osteotomies in operations for facilitation of the transport segment movement. Saulacic et al.31 mentioned that the varying amount of distraction performed in patients reporting pain in their clinical study indicated that the occurrence might be subjective. We agree with these authors, because the statement of our patient about pain may be doubtful. Soft tissue dehiscence was the most common minor complication (37.8% of distraction sites) with 6.7% of these becoming infected in a recent study. One of the causes for this may well be the distraction rate of 0.9 mm per day.30 Dehiscence and plate exposure were found in 2 of the present cases, but did not affect the functional or esthetic results. We recommended daily rinsing of the area with chlorohexidine mouthrinse for treatment. In other published studies, the prevalence of complications that compromised the final outcome is 2.7% to 20%.18,26,30,38 It was concluded in a clinical study that ADO is an effective technique to treat vertical alveolar ridge deficiencies.29 Most complications related to surgery can be avoided with adequate treatment planning.26 In other clinical studies the authors reported that most of the minor complications could be readily resolved by the use of appropriate procedures, but very close follow-up is required.19,20,29 Vertical alveolar distraction osteogenesis is not an uncomplicated procedure; however, long-term survival of dental implants inserted into distracted areas is satisfactory.30 On the other hand, Enislidis et al.39 reported that the use of subperiosteal devices for vertical augmentation of edentulous mandibles is hazardous and offers no advantage over other surgical methods and that all of the patients had severe complications. Fukuda et
al.40 also stated that vertical distraction osteogenesis for implant placement appeared to have serious risks and complications in reconstructed bone. We have not observed serious complications, such as fracture of the mandible, fracture of the transport segment, infection, or breakage of the distraction device in our study. Among the major complications, in 1 patient mucosal scar tissues prevented activation of alveolar distractor. We recommend using ADO technique in atrophic crests including scar tissues carefully. In conclusion, ADO is an effective technique to treat vertical alveolar ridge deficiencies. The intraosseous distractors can be used for distraction of small bone segments because of their small dimensions, but difficulty of vector control is the disadvantage of the Lead System. Modus maintained much more stabilization at basal and transport segments than intraosseous distractors. Alveolar distraction osteogenesis seems to be valid for simultaneous reconstruction of the alveolar bone but adequate treatment plannig is necessary for the success. Complications of this technique can be solved with simple treatments. REFERENCES 1. Adell R, Eriksson B, Lekholm U, Brånemark PI, Jemt T. A long-term follow-up study of osseointegrated implants in the treatment of totally edentulous jaws. Int J Oral Maxillofac Implants 1990;5:347-59. 2. Albrektsson T, Bergman B, Folmer T, Henry P, Higuchi K, Klinenberg I, et al. A multicenter study of osseointegrated oral implants. J Prosthet Dent 1988;60:75-84. 3. Albrektsson T, Zarb G, Worthington P, Eriksson AR. The longterm efficacy of currently used dental implants: a review and proposed criteria of success. Int J Oral Maxillofac Implants 1986;1:1-25. 4. Buser D, Mericske-Stern R, Bernard JP, Behneke A, Behneke N, Hirt HP, et al. Long-term evaluation of nonsumerged ITI implants. Part I: 8-year life table analysis of a prospective multicenter study with 2359 implants. Clin Oral Implants Res 1997;8:161-72. 5. Lekholm U, Gunne J, Henry P, Higuchi K, Linden U, Bergström, et al. Survival of the Branemark implant in partially edentulous
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6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
jaws. A 10-year prospective multicenter study. Int J Oral Maxillofac Implants 1999;14:639-45. Nyström EK, Kahnberg K-E, Gunne J. Bone grafts and Branemark implants in the treatment of severely resorbed maxilla: a two-year longitudinal study. Int J Oral Maxillofac Implants 1993;8:45-53. Satow S, Slagter AP, Stoelinga PJW, Habets LLMH. Interposed bone grafts to accommodate endosteal implants for retaining mandibular overdentures. A 1-7 year follow-up study. Int J Oral Maxillofac Surg 1997;26:358-64. Triplett RG, Schow SR. Autologous bone grafts and endosseous implants: complementary techniques. J Oral Maxillofac Surg 1996;54:489-94. Caplanis N, Sigurdsson TJ, Rohrer MD, Wikesjö UME. Effect of allogeneic, freeze-dried, demineralized bone matrixon guided bone regeneration in supraalveolar peri-implant defects in dogs. Int J Oral Maxillofac Implants 1997;12:634-42. Jensen OT, Greer RO JR, Johnson L, Kassebaum D. Vertical guided bone-graft augmentation in a new canine mandibular model. Int J Oral Maxillofac Implants 1995;10:335-44. Chin M, Toth B. Distraction osteogenesis in maxillofacial surgery using internal devices: review of five cases. J Oral Maxillofac Surg 1996;54:45-53. Hwang SJ, Jung JG, Jung JJ, Kyung SH. Vertical alveolar bone distraction at molar region using lag screw principle. J Oral Maxillofac Surg 2004;62:787-94. Horiuchi K, Uchida H, Yamamoto K, Hatano N. Anteroinferior distraction of the atrophic subtotal maxillary alveolus for implant placement: a case report. Int J Oral Maxillofac Implants 2002; 17:416-23. Maurette O’Brien PE, Allais De Maurette ME, Mazzonetto R. Distracción osteogénica alveolar: una alternativa en la reconstrucción de rebordes alveolares atróficos. Descripción de 10 casos. Rev Esp Cirug Oral Maxilofac 2004;26:41-7. Raghoebar GM, Heydenrijk K, Vissink A. Vertical distraction of the severely resorbed mandible. The Groningen distraction device. Int J Oral Maxillofac Surg 2000;29:416-20. Rachmiel A, Srouji S, Peled M. Alveolar ridge augmentation by distraction osteogenesis. Int J Oral Maxillofac Surg 2001;30: 510-17. Urbani G. Alveolar distraction before implantation: a report of five cases and a review of the literature. Int J Periodontics Restorative Dent 2001;21:569-79. Jensen OT, Cockrell R, Kuhike L, Reed C. Anterior maxillary alveolar distraction osteogenesis: a prospective 5-year clinical study. Int J Oral Maxillofac Implants 2002;17:52-68. Garcia-Garcia A, Martin-Somoza M, Gandara-Vila P, Meceiras JL. Minor complications arising in alveolar distraction osteogenesis. J Oral Maxillofac Surg 2002;60:496 – 01. Uckan S, Haydar SG, Dolanmaz D. Alveolar distraction: analysis of 10 cases. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2002;94:561-5. Van Strijen PJ, Breuning KH, Becking AG, Perdijk FBT, Tuinzing DB. Complications in bilateral mandibular distraction osteogenesis using internal devices. Oral Surg Oral Med Oral Pathol Oral Radiolo Endod 2003;96:392-7. Chiapasco M, Romeo E, Vogel G. Vertical distraction osteogenesis of edentulous ridges for improvement of oral implant positioning: A clinical report of preliminary results. Int J Oral Maxillofac Implants 2001;16:43-51. Gaggl A, Schultes G, Regauer S, Kärcher H. Healing process after alveolar ridge distraction in sheep. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2000;90:420-9. Gaggl A, Schultes G, Karcher H. Distraction implants: a new
Günbay et al. e13
25.
26.
27.
28.
29.
30.
31.
32.
33. 34.
35. 36.
37.
38.
39.
40.
operative technique for alveolar ridge augmentation. J Craniomaxillofac Surg 1999;2:214-21. Garcia-Garcia A, Somoza-Martin M, Gandara-Vila P, Saulacic N, Gandara-Rey M. Alveolar distraction before insertion of dental implants in the posterior mandible. Br J Oral Maxillofac Surg 2003;41:376-9. Chiapasco M, Consolo U, Bianchi A, Ronchi P. Alveolar distraction osteogenesis for the correction of vertically deficient edentulous ridges: a multicenter prospective study on humans. Int J Oral Maxillofac Implants 2004;19:399 – 07. Yalcin S, Ordulu M, Emes Y, Gur H, Aktas I, Caniklioglu C. Alveolar distraction osteogenesis before placement of dental ımplants. Implant Dent 2006;15:48-52. Erkut S, Uckan S. Alveolar distraction osteogenesis and implant placement in a severely resorbed maxilla: a clinical report. J Prosthet Dent 2006;95:340-3. Mazzonetto R, Allais M, Maurette PE, Moreira RWF. A retrospective study of the potential complications during alveolar distraction osteogenesis in 55 patients. Int J Oral Maxillofacial Surg 2007;36:6-10. Enislidis G, Fock N, Millesi-Schobel G, Klug C, Wittwer G, Kaan Yerit, et al. Analysis of complications following alveolar distraction osteogenesis and implant placement in the partially edentulous mandible. Oral Surg Oral Med Oral Pathol Oral Radiolo Endod 2005;100:25-30. Saulacic N, Martín MS, Camacho MAL and García García A. Complications in alveolar distraction osteogenesis: a clinical investigation. J Oral Maxillofac Surg 2007;65:267-74. Uckan S, Dolanmaz D, Kalayci A, Cilasun U. Distraction osteogenesis of basal mandibular bone for reconstruction of the alveolar ridge. Br J Oral Maxillofacial Surg 2002;40:393-6. Mattick CR. Osteogenic distraction within the craniofacial complex. Dent Update 2000;27:426-31. Baker B, Gibbons S, Woods M. Intra-alveolar distraction osteogenesis in preparation for dental implant placement combined with orthodontic/orthognathic surgical treatment: a case report. Aust Dent J 2003;48:65-8. Walker DA. Mandibular distraction osteogenesis for endoosseous dental implants. J Can Dent Assoc 2005;71:171-5. Garcia AG, Martin MS, Vila PG, Maceiras JL. Alveolar ridge osteogenesis using 2 intraosseous distractors: Uniform and nonuniform distraction. J Oral Maxillofac Surg 2002;60:1510-2. Gaggl A, Schultes G, Karcher H. Vertical alveolar ridge distraction with prosthetic treatable distractors: a clinical investigation. Int J Oral Maxillofac Implants 2000;15:701-10. Kunkel M, Wahlmann U, Reichert TE, Wegener J, Wagner W. Reconstruction of mandibular defects following tumor ablation by vertical distraction osteogenesis using intraosseous distraction devices. Clin Oral Implants Res 2005;16:89-97. Enislidis G, Fock N, Ewers R. Distraction osteogenesis with subperiosteal devices in edentulous mandibles. Br J Oral Maxillofac Surg 2005;43:399 – 03. Fukuda M, Iino M, Ohnuki T, Nagai H, Takahashi T. Vertical alveolar distraction osteogenesis with complications in a reconstructed mandible. J Oral Implantol 2003;29:185-8.
Reprint requests: Dr. Banu Özveri Koyuncu Department of Oral and Maxillofacial Surgery Ege University Bornova Turkey [email protected]