Long-term success for osteointegrated

CASE REPORT Symphyseal Bone Cylinders Tapping With the Dental Implant Into Insufficiency Bone Situated Esthetic Area at One-Stage Surgery: A Case Report and the Description of the New Technique Umut Tekin, DDS, PhD 1 * Doruk I. Kocyigit, DDS, PhD 1 Volkan Sahin, DDS, PhD 2 Periodontal defects and trauma at the anterior maxillary region can cause a severe alveolar ridge deficiency resulting in an unesthetic view. Ideal implant positioning can be compromised by inadequate alveolar bone in terms of height and width. Reconstruction of osseous defects with autogenous bone allows ideal implant positioning and creates a more natural soft and hard tissue profile, which influences esthetic crown anatomy at the anterior maxillary region. In this case report, an alveolar ridge defect due to periodontally compromised tooth extraction was filled with autogenous bone cylinder and dental implant at one-stage surgery. In the presented case, a new technique was described which included bone reconstruction of the defects at the anterior maxillary region and simultaneous placement of the dental implant. Key Words: alveolar bone defect, simultaneous implant placement, cylinder bone graft INTRODUCTION Long-term success for osteointegrated implants depends on the presence of adequate bone volume, quantity, and quality of the edentulous site. However, an insufficient amount of bone volume may result 1 Department of Oral and Maxillofacial Surgery, University of Kirikkale, Kirikkale, Turkey. 2 Department of Prosthodontics, University of Kirikkale, Kirikkale, Turkey. *Corresponding author, e-mail: umutekin@gmail.com DOI: 10.1563/AAID-JOI-D-09-00096.1 from trauma, tooth extraction, or infectious diseases such as periodontitis. Alveolar ridge morphology is particularly important in performing esthetic prosthetic rehabilitation and implant placement in the anterior maxilla. 1,2 A number of different techniques have been described to augment the deficient alveolar ridges and to allow dental implant placement either in a simultaneous or consecutive approach. Several techniques for this procedure may be considered, such Journal of Oral Implantology 589

Symphyseal Bone Cylinders as guided bone regeneration, bone block grafting, and ridge splitting for bone expansion. 3 6 Ridge dimensions affect implant length and width. Moreover, a large interarch space produces an unfavorable crownto-root ratio in the prosthetic restoration. 7 A classification of alveolar ridge defects has been described to standardize communication among clinicians in the selection and sequencing of reconstructive procedures designed to correct different types of defects. 8 Bone augmentation procedures are routinely required before dental implant placement. Thus, the bone augmentation technique employed to reconstruct these ridge defects depends on the horizontal and vertical extent of the defect. Autogenous bone grafts have been used in alveolar ridge augmentation for many years and have long been considered the gold standard for jaw reconstruction. 9,10 However, in recent years, autogenous stem cells may become a new platinum standard. 11 Autogenous grafts are harvested from intraoral sites such as the mandibular symphysis, ramus, or maxillary tuberosity, and extraoral sites such as the iliac crests, ribs, cranium, and tibial metaphyses. Extraoral sites are used when significant amounts of bone are required to reconstruct larger deficiencies. 12,13 Autogenous bone graft harvested from extraoral sites is often associated with complications and morbidity of the donor site and requires hospitalization and mostly general anesthesia. Block bone grafts harvested from the symphysis can be used for predictable bone augmentation up to 6 mm in horizontal and vertical dimensions. 14 In addition, the intraoral grafts derived from intramembranous bone have less resorption than the grafts derived from endochondral bones like the iliac crest, fibula, and tibia. 15 The aim of the present case report is to describe a technique and to evaluate the success of extensive bone reconstruction of atrophic maxillary alveolar ridges utilizing intraoral cylinder bone grafts and simultaneous dental implant placement. CASE REPORT A 61-year-old white male patient suffering from the mobility of maxillary incisor tooth number 9 was referred to the Department of Oral and Maxillofacial Surgery Clinic at the University of Kirikkale Faculty of Dentistry. In the clinical examination, tooth number 9 showed lateral and vertical mobility. Initial radiographic examination revealed advanced bone loss at the number 9 site (Figure 1). A treatment plan including the extraction of the tooth and immediate implant placement was developed and accepted by the patient. Tooth number 9 was extracted, and a combination of vertical and horizontal ridge deficiency was observed at the extraction site. Placement of the dental implant directly to the extraction site would lead to apically positioned abutment-crown junction and would have resulted in an extremely unfavorable crown-to-root ratio and to an unesthetic restoration. Therefore, it was decided to augment the ridge defect using mandibular symphyseal bone cylinder graft and simultaneous placement of the dental implant. The procedure was performed under local anesthesia (articaine hydrochloride 4% with epinephrine 1:100 000). A full-thickness flap with vertical releasing incisions was reflected. Horizontal and vertical ridge deficiency was evident (Figure 2). After the bony defect was evaluated and measured, the symphysis was exposed by a sulcular incision between the mandibular canine teeth. A trephine burr with an internal diameter of 10 mm (KLS Martin and Mondeal Medical Systems, Tuttlingen, Germany) was used to remove bone cylinder, in the length of 8 mm (Figure 3). The osteotomy was performed at least 5 mm apical to the mandibular incisors under copious irrigation. The bone cylinder 590 Vol. XXXVII/No. Five/2011

Tekin et al FIGURES 1 4. FIGURE 1. Preoperative radiographic view of the patient. Dramatic bone loss around tooth number 9. FIGURE 2. Vertical and horizontal bone deficiency after extraction. FIGURE 3. Symphyseal bone cylinder harvested from the chin. FIGURE 4. Bone cylinder, simultaneously tapped with the help of dental implant into the bone defect. Journal of Oral Implantology 591

Symphyseal Bone Cylinders was then tapped into the extraction socket, and an implant was placed into the bone cylinder (3.7 mm wide and 16 mm long; Implant Direct LLC, Calif) (Figure 4). Four months later, healing cap surgery was performed after panoramic examination (Figures 5 and 6). One week later, a definitive crown was successfully placed (Figure 7). After restoration, the implant was followed for 1 year without any clinical and radiographic problems or complications. DISCUSSION The vertical alveolar bone defects can be corrected prior to or simultaneous with implant placement. The major advantage of a one-stage procedure, in addition to the lower number of surgical interventions required and reduced overall healing time, is that the bone graft stabilization is provided with implants. Generally, the single-stage approach has proven to be safe and effective.16 An important disadvantage of the combined graft-implant procedure is that the graft failure also implies implant failure. Furthermore, graft failure may result in an implant that osteointegrated in its apical zone but may not be supported by bone in its coronal zone. In the presented case of a one-stage approach, the implant and vertical ridge augmentation were completed simultaneously. The primer implant fixation and stabilization was found to be successful. Complete or partial graft failure was not experienced. Lekholm et al17 reported that a twostage approach provides higher success rates than a one-stage approach. However, if complete initial stability and ideal implant position is accomplished, a one-stage method can be as successful as a two-stage procedure. In our case, initial implant stability was provided. The placement of implants into grafted bone is today a well-established treatment. 592 Vol. XXXVII/No. Five/2011 FIGURES 5 7. FIGURE 5. Postoperative radiographic view after 4 months. FIGURE 6. A periapical radiograph demonstrating the peri-implant bone. FIGURE 7. Intraoral view of the final restoration. The use of autogenous bone is considered to be the gold standard.18 Autogenous intramembranous bone graft provides several advantages, such as minimal resorption and high concentration of bone morphogenetic

Tekin et al proteins and growth factors. 19 The mandibular symphysis, as a donor site for the ridge augmentation, provides a relatively small quantity of bone, but offers easier access, low morbidity, minimal graft resorption, and the avoidance of an undesirable cutaneous scar. 20,21 In addition, the bone graft could be harvested in the form of a bone cylinder, which simplifies stabilization in the recipient sites. Simion et al 16 reported that the characteristics of a regenerated bone depend more upon the bone quality of the recipient site than the quality of the grafted bone. Kaufman and Wang 3 used bone cores, but preferred a two-stage approach over a one-stage approach. However, we preferred a one-stage approach in order to shorten the treatment duration. Typically, two-point stabilization of grafts has been shown to offer the best chance for graft success. In our technique, autogenous bone cylinder was shaped to fit the size of the bony defect, and adapted to the defect. The first point for stabilization for this technique was obtained by tapping the graft into the recipient site, which was suitable for the tapping. The second point for stabilization was secured by using the implant. Furthermore, two-point stabilization was achieved. Stabilization of the bone cylinder autogenous graft is important because graft mobility can result in nonunion and resorption. Tensionfree primary closure of the recipient site is also momentous for successful results as are other bone grafting methods. The trephine technique is useful in alveolar bone grafting because it provides structural bone grafts and cancellous bone. Harvesting of bone from symphysis using a trephine appears to be safe and results in minimal morbidity for many maxillofacial procedures. The authors consider the ascending ramus and maxillary tuberosity to be suitable donor sites for this technique for getting cylinder block grafts. However, further cases are needed to explain the advantages and disadvantages of different donor sites on the efficiency of this technique. In several techniques, fixation of the bone block requires usage of screw or plate fixation. But, in this technique, tapping the bone block with the dental implant into the fresh extraction socket provides the fixation without any screw or plate. This helps to decrease the operation time, cost of the operation, and handling complications due to screw or plate fixation. As a result, this technique provides a more practical approach on bone grafting and dental implant surgery. There are some prerequisites that need to be fulfilled when our technique is considered for replacing single maxillary teeth in an esthetic zone. First, establishing good primary stability must be the major concern. This can only be granted when long implants are used, crossing the apical portion of the healthy bone. Thus, sufficient bone volume in this area is an important prerequisite. Second, immediate provisionalization should not be performed in cases of buccal bone defects extending to the buccal crest. Third, in our technique, screw-type tapered implants must be used so that it is easier to achieve primary stability. CONCLUSION In the described one-stage technique, the bone cylinders are stabilized by tapping and implanting into the recipient site; this allowed a decrease of the chair-side time. Moreover, harvesting of bone from the symphysis using a trephine burr is simpler and more conservative than the conventional osteotomy technique. Vertical alveolar ridge augmentation using autogenous bone cylinder with simultaneous implant placement can effectively increase alveolar ridge height and allow for an acceptable level of osseointegration. We recommend at least 5 mm of healthy bone beyond the apex and Journal of Oral Implantology 593

Symphyseal Bone Cylinders a bony length of 10 mm or greater for stability when placing implants. Our technique seems appealing for the clinician. This technique provides significant advantages, including fewer surgical procedures and shorter treatment time. Further investigations are necessary to determine the clinical applicability and long-term results of this new technique. REFERENCES 1. McCarthy C, Patel RR, Wragg PF, Brook IM. Dental implants and onlay bone grafts in the anterior maxilla: analysis of clinical outcome. Int J Oral Maxillofac Implants. 2003;18:238 241. 2. Fukuda M, Takahhashi T, Yamaguchi T. Bone grafting technique to increase interdental alveolar bone height for placement of an implant. Br J Oral Maxillofac Surg. 2000;38:16 18. 3. Kaufman E, Wang PD. Localized vertical maxillary ridge augmentation using symphyseal bone cores: a technique and case report. Int J Oral Maxillofac Implants. 2003;18:293 298. 4. Cordaro L, Amade DS, Cordaro M. Clinical results of alveolar ridge augmentation with mandibular block bone grafts in partially edentulous patients prior to implant placement. Clin Oral Implants Res. 2002;13:103 111. 5. Buser D, Dula K, Hirt HP, Schenk RK. Lateral ridge augmentation using autografts and barrier membranes: a clinical study with 40 partially edentulous patients. J Oral Maxillofac Surg. 1996;54:420 432. 6. Basa S, Varol A, Turker N. Alternative bone expansion technique for immediate placement of implants in the edentulous posterior mandibular ridge: a clinical report. Int J Oral Maxillofac Implants. 2004;19: 554 558. 7. Mecall RA, Rosenfield AL. The influence of residual ridge resorption patterns on fixture placement and tooth position. Part I. Int J Periodontics Restorative Dent. 1991;11:9 23. 8. Seibert JS, Cohen DW. Periodontal considerations in preparation for fixed and removal prosthodontics. Dent Clin North Am. 1987;31:529 555. 9. Simion M, Fontana F. Autogenous and xenogeneic bone grafts fort he bone regeneration. A literature review. Minerva Stomatol. 2004;53:191 206. 10. Marx RE. Biology of bone grafts. In: Kelly JPW, ed. OMS Knowledge Update. Vol 1. Rosemont, Ill: American Association of Oral and Maxillofacial Surgeons; 1994:RCN3. 11. Soltan M, Smiler D, Gailani F. A new platinum standard for bone grafting: autogenous stem cells. Implant Dent. 2005;14:322 327. 12. Gutta R, Waite PD. Cranial bone grafting and simultaneous implants: a submental technique to reconstruct the atrophic mandible. Br J Oral Maxillofac Surg. 2008;46:477 499. 13. Akkocaoglu M, Cehreli MC, Tekdemir I, et al. Primary stability of simultaneously placed dental implants in extraoral donor graft sites: a human cadaver study. J Oral Maxillofac Surg. 2007;65:400 407. 14. Pikos MA. Mandibular block autografts for alveolar ridge augmentation. Atlas Oral Maxillofac Surg Clin North Am. 2005;13:91 107. 15. Rosenthal AH, Buchman SR. Volume maintenance of inlay bone grafts in the craniofacial skeleton. Plast Reconstr Surg. 2003;112:802 811. 16. Simion M, Jovanovic SA, Trisi P, Scarano A, Piattelli A. Vertical ridge augmentation around dental implants using a membrane technique and autogenous bone or allografts in humans. Int J Periodontics Restorative Dent. 1998;18:8 23. 17. Lekholm U, Wannfors K, Isaksson S, Adielsson B. Oral implants in combination with bone grafts. A 3-year retrospective multicenter study using the Branemark implant system. Int J Oral Maxillofac Surg. 1999;28:181 187. 18. Simion M, Fontana F. Autogenous and xenogeneic bone grafts for the bone regeneration. A literature review. Minerva Stomatol. 2004;53:191 206. 19. Canalis E. Effect of growth factors on bone cell replication and differentiation. Clin Orthop Relat Res. 1985;193:246 263. 20. Borstlap WA, Heidbuchel KL, Freihofer HP, Kuijpers Jagtman AM. Early secondary bone grafting of alveolar cleft defects. A comparison between chin and rib grafts. J Craniomaxillofac Surg. 1990;18:201 205. 21. Nkenke E, Schultze-Mosgau S, Radespiel-Troger M, Kloss F, Neukam FW. Morbidity of harvesting of chin grafts: a prospective study. Clin Oral Implants Res. 2001:12;495 502. 594 Vol. XXXVII/No. Five/2011