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Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma
YBJOM-5237; No. of Pages 4
ARTICLE IN PRESS Available online at www.sciencedirect.com
ScienceDirect British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma J. Breeze ∗ , J. Patel, M.S. Dover, R.W. Williams Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham B15 2GW Accepted 2 August 2017
Abstract Autogenous bone remains the gold standard for augmentation of the alveolar ridge in congenital hypodontia and appreciable post-traumatic deformity. This generally reflects the volume of material required for such defects and the osteogenic potential of the grafts. Morbidity at the donor site and success rates may lead to autogenous grafts being superseded by xenografts or alloplastic materials in the future, but we know of little evidence to confirm this. All patients having augmentation of the alveolar ridge or sinus lift to enable subsequent placement of implants between 01 January 2009 and 31 December 2016 were identified from a prospectively-gathered database held at the Queen Elizabeth Hospital, Birmingham. Morbidity was recorded, with overall success defined as a graft that enabled subsequent placement of an implant. During this period the following grafts: calvarial (n = 4), iliac crest (n = 4), and ramus (n = 149) were recorded, as well as 53 sinus lifts. Sinus ® lift augmentation with BioOss had the highest success rate (51/53). Calvarial and iliac crest grafts had higher failure rates (2/4 and 3/4, respectively) than those from the mandibular ramus (6/149, 4%). Fifteen of 149 (10%) ramus grafts resulted in transient anaesthesia of the inferior alveolar nerve but no patients developed any permanent morbidity at the donor or recipient sites. Ramus grafts are a predictable method of bone augmentation with only transient morbidity at the donor site. Higher failure rates for extraoral grafts probably reflect their use in more challenging cases when more bone is required. Bilateral ramus grafts are an alternative to extraoral grafts and may be supplemented by bovine-derived particulate grafts with no appreciable increase in complications. Crown Copyright © 2017 Published by Elsevier Ltd on behalf of The British Association of Oral and Maxillofacial Surgeons. All rights reserved.
Keywords: Hypodontia; Oligodontia; Anodontia; Surgery; Management; Maxillofacial; Bone; Graft; Sinus; Lift
Introduction Hypodontia is the term most commonly applied to a condition in which teeth congenitally fail to develop.1 Patients generally present in their early teenage years after secondary dentition has failed to erupt.2 Such patients are best man∗ Corresponding author at: Department of Oral and Maxillofacial Surgery, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham B15 2GW. E-mail address: [email protected] (J. Breeze).
aged by a multidisciplinary team in hospital, which enables input from restorative dentists, orthodontists, and surgeons.3 The rehabilitation of edentulous ridges in cases of congenital hypodontia follow algorithms similar to those of patients with teeth missing from other causes.4 Rehabilitation may be with fixed or removable prostheses. Retention is improved by the use of implants, and atrophic alveolar ridges may require augmentation to enable their placement.5,6 Augmentation may be either vertical or horizontal, and may comprise block or particulate grafts that include membranes to guide bony regeneration,7 and the different
http://dx.doi.org/10.1016/j.bjoms.2017.08.001 0266-4356/Crown Copyright © 2017 Published by Elsevier Ltd on behalf of The British Association of Oral and Maxillofacial Surgeons. All rights reserved.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
YBJOM-5237; No. of Pages 4
2
ARTICLE IN PRESS J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
Fig. 3. Lag screws in place after bone grafts to the maxilla and mandible from the iliac crest.
Fig. 1. Clinical photograph of a lateral window approach to a maxillary sinus.
Fig. 2. Radiograph illustrating the lateral window approach to the maxillary sinus using particulate graft to show the potential height of bone that can be achieved.
augmentation techniques are normally based on the classification of resorption of the alveolar crest by Cawood and Howell.8 Materials described for augmentation include autogenous bone, cadaveric grafts, xenografts, and alloplastics. 9 Sinus lifting may be used in conjunction with particulate grafts, and can be done using both crestal and lateral window techniques (Figs. 1 and 2).10 If the cause of the edentulous ridge is not congenital, the standard technique for augmentation is a particulate graft, often together with a membrane or a mesh. Xenograft (such ® as Bio-Oss , Geistlich Biomaterials) and cadaveric (such as ® DBX , DePuy Syntheses) particulates are the most successful, but are in some cases limited by cultural sensitivities. Alloplastic materials are generally based on calcium phosphate cements and are similar in composition to bone with bioactive (able to directly bond to bone to form a uniquely strong interface) and osteoconductive (able to serve as a template or guide for the newly-forming bone) properties.11 Calcium phosphate biomaterials currently have lower success rates than other materials, particularly in large defects.11–13
Autogenous bone remains the gold standard for augmentation of the alveolar ridge in congenital hypodontia and appreciable post-traumatic deformity.5,7 This generally reflects the volume of material required for such defects and the osteogenic potential of such grafts. However, extraorallyderived autogenous bone grafts are rarely used outside hospital, for several reasons. Extraoral harvest (such as from the calvarium or iliac crest) is clearly unrealistic in primary care and has the potential for appreciable morbidity (Fig. 3).5,6 Intraoral grafts (such as from the ramus) can be reliably harvested under local anaesthesia but there are concerns about the risk of damage to the inferior alveolar nerve and potential infection of the recipient site.14 Morbidity at the donor site and improving success rates may lead to autogenous grafts being superseded by xenografts or alloplastic materials in the future, but we know of little or no evidence to confirm this. The aim of this study was to report the success rates and complications of autogenous bone grafts and sinus lifts to find out how useful they are in the rehabilitation of patients with congenital hypodontia and after trauma.
Method All patients who had augmentation of the alveolar ridge or sinus to enable subsequent placement of implants between 01 January 2009 and 31 December 2016 were identified from a prospectively-gathered database held at the Queen Elizabeth Hospital, Birmingham. Only patients who had autogenous bone grafts and in whom the indication for treatment was congenital hypodontia or dentoalveolar trauma were included in the analysis. Variables comprised the sites from which the donor grafts were harvested, and which were augmented. Perioperative and postoperative complications were recorded, with overall success defined as a graft that enabled subsequent placement of an implant. We compared the overall success rate and incidence of postoperative complications for smokers and non-smokers using the chi square test, and probabilities of 0.05 or less were accepted as significant.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
ARTICLE IN PRESS
YBJOM-5237; No. of Pages 4
J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
3
Table 1 Successes and complications in autogenous bone grafts and sinus lifts done for congenital hypodontia and trauma. Data are number (%). Type of augmentation
Number
Success of first graft in non- smokers
Success of first graft in smokers
Incidence of transient complications
Calvarial Iliac crest Mandibular ramus ® Sinus lift with BioOss
4 4 149 53
2/4 3/4 140/143 (98) 51/51
None None 3/6 0/2
0/4 0/4 15/149 (10) 0/53
Results A total of 146 patients had autogenous bony augmentation, with a mean (SD) duration between bone grafting and placement of implants of 253 (84) days (Table 1). For 129/146 patients the indication for surgery was congenital hypodontia with a mean (range) age of 29 (16-66) years at the time of operation. The remaining 17 patients had bone grafts for reconstruction after trauma, with a mean (range) age of 35 (18-76) years. Four of the 146 patients had repeat procedures (one sinus lift and three bone grafts). In total, sinus lift aug® mentation with BioOss had the lowest failure rate. Calvarial and iliac crest grafts had higher failure rates than grafts of the mandibular ramus. Failure was more commonly the result of resorption after infection at the recipient site (5/6) than resorption without infection (1/6). Twelve recipient sites were resorbed, including four with mucosal dehiscence. However, only a single graft resorbed so much that placement of an implant was not possible. Fifteen of the 149 ramus grafts (10%) resulted in transient anaesthesia of the inferior alveolar nerve, and we encountered no other morbidity at the donor site. No patients developed permanent morbidity at either the donor or recipient site. Ramus bone grafts and sinus lifts in the 8/146 patients who smoked cigarettes were significantly more likely to fail than those in the 136/146 patients who did not smoke (p = 0.0012). There was no significant difference in the incidence of postoperative anaesthesia in those who smoked and those did not (p = 0.452).
Discussion The prosthodontic rehabilitation of severely atrophic alveolar ridges still requires autogenous bone to improve predictable placement of implants.6 Donor sites for autogenous bone differ in the amounts that can be harvested, in rates of subsequent resorption, and in donor site morbidity.9 Survival of subsequent implants is known to be higher when larger amounts of residual bone are present.6 However, most papers have looked only at survival of the implant and not the survival of the bone graft itself, which may be misleading as there are other causes of failure that are beyond the control of the surgeon inserting the bone graft.12 Smoking, for example, is known to be associated with higher failure rates of implants, and we found that more bone grafts failed in smokers than in non-smokers.5 Our failures were primarily the result of infec-
Fig. 4. Clinical appearance after rehabilitation with an implant using autologous augmentation with an iliac crest bone graft.
Fig. 5. The same patient as in Fig. 4 showing the iliac crest bone graft 10 years postoperatively with resorptive changes under a fixed bridge.
tion but even among the 12 grafts that became infected and required treatment with antibiotics, subsequent placement of implants was still possible in 11/12 grafts. Harvest of extraoral bone has been practiced less in recent years because of the perception of potential donor site morbidity and the need for admission to hospital.6 However, although our numbers were low, we found no donor site morbidity in those extraoral harvest sites. Calvarial and iliac crest grafts did result in higher failure rates than ramus grafts (Table 1) but this is more likely to reflect their use in more challenging cases where more bone is required. Our experience has been that extraoral bone grafts in postmenopausal female patients are associated with far higher rates of failure than other groups of patients, which may be the result of reduced bone density (Figs. 4 and 5). Ramus grafts were a predictable method of bony augmentation. In our series implants could not be placed in only
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
ARTICLE IN PRESS
YBJOM-5237; No. of Pages 4
4
J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
6 of 149 ramus grafts (4%), which is similar to the findings of a recent large systematic review of implants placed after onlay bone grafts.12 Ramus grafts are well tolerated by patients, with only 15/149 (10%) developing transient donor site morbidity and no patients having permanent symptoms. Our experience is that bilateral ramus grafts can be used in selected cases as an alternative to extraoral harvest in cases where more bone is required. They may also be supplemented with particulate bovine xenografts with no appreciable increase in complications. Ramus grafts can also be harvested at the same time as third molars are extracted using only a small extension to the existing incision.14 We use a lateral window approach for sinus lift augmentation in our unit, as our experience is that raising a mucoperiosteal flap allows for a clinical assessment of the quality of the bone, and there is a higher failure rate with transcrestal approaches to grafting of the sinus floor than through a lateral approach.15 This is important in the prediction of subsequent placement of implants and cannot be assessed using a blind transcrestal technique. Sinus lift augmentation enabled subsequent implant placement in 51/53 of cases, similar to the 424/443 (96%) found in a recent large systematic review.12 However, success is highly dependent on the patient not smoking, and augmentation of the xenograft with mate® rials such as BioOss requires some existing bone within the sinus, otherwise additional augmentation with autogenous bone will be required.
Conflict of interest We have no conflicts of interest.
Ethics statement/confirmation of patients’ permission Ethics approval not required. The patients’ permission was obtained.
References 1. Nunn JH, Carter NE, Gillgrass TJ, et al. The interdisciplinary management of hypodontia: background and role of paediatric dentistry. Br Dent J 2003;194:245–51. 2. Hobson RS, Carter NE, Gillgrass TJ, et al. The interdisciplinary management of hypodontia: the relationship between an interdisciplinary team and the general dental practitioner. Br Dent J 2003;194:479–82. 3. Worsaae N, Jensen BN, Holm B, et al. Treatment of severe hypodontiaoligodontia-an interdisciplinary concept. Int J Oral Maxillofac Surg 2007;36:473–80. 4. Creton M, Cune M, Verhoeven W, et al. Implant treatment in patients with severe hypodontia: a retrospective evaluation. J Oral Maxillofac Surg 2010;68:530–8. 5. Nystrom E, Nilson H, Gunne J, et al. A 9-14 year follow-up of onlay bone grafting in the atrophic maxilla. Int J Oral Maxillofac Surg 2009;38:111–6. 6. Quiles JC, Souza FA, Bassi AP, et al. Survival rate of osseointegrated implants in atrophic maxillae grafted with calvarial bone: a retrospective study. Int J Oral Maxillofac Surg 2015;44:239–44. 7. Durey K, Carter L, Chan M. The management of severe hypodontia. Part 2: bone augmentation and the provision of implant supported prostheses. Br Dent J 2014;216:63–8. 8. Cawood JI, Howell RA. A classification of the edentulous jaws. Int J Oral Maxillofac Surg 1988;17:232–6. 9. Hallman M, Thor A. Bone substitutes and growth factors as an alternative/complement to autogenous bone for grafting in implant dentistry. Periodontol 2000 2008;47:172–92. 10. Felice P, Pistilli R, Barausse C, et al. Short implants as an alternative to crestal sinus lift: A 1-year multicentre randomised controlled trial. Eur J Oral Implantol 2015;8:375–84. 11. Xie C, Lu H, Li W, et al. The use of calcium phosphate-based biomaterials in implant dentistry. J Mater Sci Mater Med 2012;23:853–62. 12. Aghaloo TL, Moy PK. Which hard tissue augmentation techniques are the most successful in furnishing bony support for implant placement? Int J Oral Maxillofac Implants 2007;22(suppl):49–70. 13. Bohner M, Gbureck U, Barralet JE. Technological issues for the development of more efficient calcium phosphate bone cements: a critical assessment. Biomaterials 2005;26:6423–9. 14. Deeb GR, Laskin DM, Deeb JG. Simultaneous impacted third molar extraction and lateral ramus block graft harvest for horizontal ridge augmentation: A case series. J Oral Maxillofac Surg 2017;75:509–13. 15. Katsuyama H, Jensen SS. Sinus floor elevation procedures, vol 5. ITI Treatment Guide. New Malden: Quintessence Publishing Company; 2011.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
ARTICLE IN PRESS Available online at www.sciencedirect.com
ScienceDirect British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma J. Breeze ∗ , J. Patel, M.S. Dover, R.W. Williams Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham B15 2GW Accepted 2 August 2017
Abstract Autogenous bone remains the gold standard for augmentation of the alveolar ridge in congenital hypodontia and appreciable post-traumatic deformity. This generally reflects the volume of material required for such defects and the osteogenic potential of the grafts. Morbidity at the donor site and success rates may lead to autogenous grafts being superseded by xenografts or alloplastic materials in the future, but we know of little evidence to confirm this. All patients having augmentation of the alveolar ridge or sinus lift to enable subsequent placement of implants between 01 January 2009 and 31 December 2016 were identified from a prospectively-gathered database held at the Queen Elizabeth Hospital, Birmingham. Morbidity was recorded, with overall success defined as a graft that enabled subsequent placement of an implant. During this period the following grafts: calvarial (n = 4), iliac crest (n = 4), and ramus (n = 149) were recorded, as well as 53 sinus lifts. Sinus ® lift augmentation with BioOss had the highest success rate (51/53). Calvarial and iliac crest grafts had higher failure rates (2/4 and 3/4, respectively) than those from the mandibular ramus (6/149, 4%). Fifteen of 149 (10%) ramus grafts resulted in transient anaesthesia of the inferior alveolar nerve but no patients developed any permanent morbidity at the donor or recipient sites. Ramus grafts are a predictable method of bone augmentation with only transient morbidity at the donor site. Higher failure rates for extraoral grafts probably reflect their use in more challenging cases when more bone is required. Bilateral ramus grafts are an alternative to extraoral grafts and may be supplemented by bovine-derived particulate grafts with no appreciable increase in complications. Crown Copyright © 2017 Published by Elsevier Ltd on behalf of The British Association of Oral and Maxillofacial Surgeons. All rights reserved.
Keywords: Hypodontia; Oligodontia; Anodontia; Surgery; Management; Maxillofacial; Bone; Graft; Sinus; Lift
Introduction Hypodontia is the term most commonly applied to a condition in which teeth congenitally fail to develop.1 Patients generally present in their early teenage years after secondary dentition has failed to erupt.2 Such patients are best man∗ Corresponding author at: Department of Oral and Maxillofacial Surgery, Queen Elizabeth Hospital Birmingham, Mindelsohn Way, Edgbaston, Birmingham B15 2GW. E-mail address: [email protected] (J. Breeze).
aged by a multidisciplinary team in hospital, which enables input from restorative dentists, orthodontists, and surgeons.3 The rehabilitation of edentulous ridges in cases of congenital hypodontia follow algorithms similar to those of patients with teeth missing from other causes.4 Rehabilitation may be with fixed or removable prostheses. Retention is improved by the use of implants, and atrophic alveolar ridges may require augmentation to enable their placement.5,6 Augmentation may be either vertical or horizontal, and may comprise block or particulate grafts that include membranes to guide bony regeneration,7 and the different
http://dx.doi.org/10.1016/j.bjoms.2017.08.001 0266-4356/Crown Copyright © 2017 Published by Elsevier Ltd on behalf of The British Association of Oral and Maxillofacial Surgeons. All rights reserved.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
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2
ARTICLE IN PRESS J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
Fig. 3. Lag screws in place after bone grafts to the maxilla and mandible from the iliac crest.
Fig. 1. Clinical photograph of a lateral window approach to a maxillary sinus.
Fig. 2. Radiograph illustrating the lateral window approach to the maxillary sinus using particulate graft to show the potential height of bone that can be achieved.
augmentation techniques are normally based on the classification of resorption of the alveolar crest by Cawood and Howell.8 Materials described for augmentation include autogenous bone, cadaveric grafts, xenografts, and alloplastics. 9 Sinus lifting may be used in conjunction with particulate grafts, and can be done using both crestal and lateral window techniques (Figs. 1 and 2).10 If the cause of the edentulous ridge is not congenital, the standard technique for augmentation is a particulate graft, often together with a membrane or a mesh. Xenograft (such ® as Bio-Oss , Geistlich Biomaterials) and cadaveric (such as ® DBX , DePuy Syntheses) particulates are the most successful, but are in some cases limited by cultural sensitivities. Alloplastic materials are generally based on calcium phosphate cements and are similar in composition to bone with bioactive (able to directly bond to bone to form a uniquely strong interface) and osteoconductive (able to serve as a template or guide for the newly-forming bone) properties.11 Calcium phosphate biomaterials currently have lower success rates than other materials, particularly in large defects.11–13
Autogenous bone remains the gold standard for augmentation of the alveolar ridge in congenital hypodontia and appreciable post-traumatic deformity.5,7 This generally reflects the volume of material required for such defects and the osteogenic potential of such grafts. However, extraorallyderived autogenous bone grafts are rarely used outside hospital, for several reasons. Extraoral harvest (such as from the calvarium or iliac crest) is clearly unrealistic in primary care and has the potential for appreciable morbidity (Fig. 3).5,6 Intraoral grafts (such as from the ramus) can be reliably harvested under local anaesthesia but there are concerns about the risk of damage to the inferior alveolar nerve and potential infection of the recipient site.14 Morbidity at the donor site and improving success rates may lead to autogenous grafts being superseded by xenografts or alloplastic materials in the future, but we know of little or no evidence to confirm this. The aim of this study was to report the success rates and complications of autogenous bone grafts and sinus lifts to find out how useful they are in the rehabilitation of patients with congenital hypodontia and after trauma.
Method All patients who had augmentation of the alveolar ridge or sinus to enable subsequent placement of implants between 01 January 2009 and 31 December 2016 were identified from a prospectively-gathered database held at the Queen Elizabeth Hospital, Birmingham. Only patients who had autogenous bone grafts and in whom the indication for treatment was congenital hypodontia or dentoalveolar trauma were included in the analysis. Variables comprised the sites from which the donor grafts were harvested, and which were augmented. Perioperative and postoperative complications were recorded, with overall success defined as a graft that enabled subsequent placement of an implant. We compared the overall success rate and incidence of postoperative complications for smokers and non-smokers using the chi square test, and probabilities of 0.05 or less were accepted as significant.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
ARTICLE IN PRESS
YBJOM-5237; No. of Pages 4
J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
3
Table 1 Successes and complications in autogenous bone grafts and sinus lifts done for congenital hypodontia and trauma. Data are number (%). Type of augmentation
Number
Success of first graft in non- smokers
Success of first graft in smokers
Incidence of transient complications
Calvarial Iliac crest Mandibular ramus ® Sinus lift with BioOss
4 4 149 53
2/4 3/4 140/143 (98) 51/51
None None 3/6 0/2
0/4 0/4 15/149 (10) 0/53
Results A total of 146 patients had autogenous bony augmentation, with a mean (SD) duration between bone grafting and placement of implants of 253 (84) days (Table 1). For 129/146 patients the indication for surgery was congenital hypodontia with a mean (range) age of 29 (16-66) years at the time of operation. The remaining 17 patients had bone grafts for reconstruction after trauma, with a mean (range) age of 35 (18-76) years. Four of the 146 patients had repeat procedures (one sinus lift and three bone grafts). In total, sinus lift aug® mentation with BioOss had the lowest failure rate. Calvarial and iliac crest grafts had higher failure rates than grafts of the mandibular ramus. Failure was more commonly the result of resorption after infection at the recipient site (5/6) than resorption without infection (1/6). Twelve recipient sites were resorbed, including four with mucosal dehiscence. However, only a single graft resorbed so much that placement of an implant was not possible. Fifteen of the 149 ramus grafts (10%) resulted in transient anaesthesia of the inferior alveolar nerve, and we encountered no other morbidity at the donor site. No patients developed permanent morbidity at either the donor or recipient site. Ramus bone grafts and sinus lifts in the 8/146 patients who smoked cigarettes were significantly more likely to fail than those in the 136/146 patients who did not smoke (p = 0.0012). There was no significant difference in the incidence of postoperative anaesthesia in those who smoked and those did not (p = 0.452).
Discussion The prosthodontic rehabilitation of severely atrophic alveolar ridges still requires autogenous bone to improve predictable placement of implants.6 Donor sites for autogenous bone differ in the amounts that can be harvested, in rates of subsequent resorption, and in donor site morbidity.9 Survival of subsequent implants is known to be higher when larger amounts of residual bone are present.6 However, most papers have looked only at survival of the implant and not the survival of the bone graft itself, which may be misleading as there are other causes of failure that are beyond the control of the surgeon inserting the bone graft.12 Smoking, for example, is known to be associated with higher failure rates of implants, and we found that more bone grafts failed in smokers than in non-smokers.5 Our failures were primarily the result of infec-
Fig. 4. Clinical appearance after rehabilitation with an implant using autologous augmentation with an iliac crest bone graft.
Fig. 5. The same patient as in Fig. 4 showing the iliac crest bone graft 10 years postoperatively with resorptive changes under a fixed bridge.
tion but even among the 12 grafts that became infected and required treatment with antibiotics, subsequent placement of implants was still possible in 11/12 grafts. Harvest of extraoral bone has been practiced less in recent years because of the perception of potential donor site morbidity and the need for admission to hospital.6 However, although our numbers were low, we found no donor site morbidity in those extraoral harvest sites. Calvarial and iliac crest grafts did result in higher failure rates than ramus grafts (Table 1) but this is more likely to reflect their use in more challenging cases where more bone is required. Our experience has been that extraoral bone grafts in postmenopausal female patients are associated with far higher rates of failure than other groups of patients, which may be the result of reduced bone density (Figs. 4 and 5). Ramus grafts were a predictable method of bony augmentation. In our series implants could not be placed in only
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001
ARTICLE IN PRESS
YBJOM-5237; No. of Pages 4
4
J. Breeze et al. / British Journal of Oral and Maxillofacial Surgery xxx (2017) xxx–xxx
6 of 149 ramus grafts (4%), which is similar to the findings of a recent large systematic review of implants placed after onlay bone grafts.12 Ramus grafts are well tolerated by patients, with only 15/149 (10%) developing transient donor site morbidity and no patients having permanent symptoms. Our experience is that bilateral ramus grafts can be used in selected cases as an alternative to extraoral harvest in cases where more bone is required. They may also be supplemented with particulate bovine xenografts with no appreciable increase in complications. Ramus grafts can also be harvested at the same time as third molars are extracted using only a small extension to the existing incision.14 We use a lateral window approach for sinus lift augmentation in our unit, as our experience is that raising a mucoperiosteal flap allows for a clinical assessment of the quality of the bone, and there is a higher failure rate with transcrestal approaches to grafting of the sinus floor than through a lateral approach.15 This is important in the prediction of subsequent placement of implants and cannot be assessed using a blind transcrestal technique. Sinus lift augmentation enabled subsequent implant placement in 51/53 of cases, similar to the 424/443 (96%) found in a recent large systematic review.12 However, success is highly dependent on the patient not smoking, and augmentation of the xenograft with mate® rials such as BioOss requires some existing bone within the sinus, otherwise additional augmentation with autogenous bone will be required.
Conflict of interest We have no conflicts of interest.
Ethics statement/confirmation of patients’ permission Ethics approval not required. The patients’ permission was obtained.
References 1. Nunn JH, Carter NE, Gillgrass TJ, et al. The interdisciplinary management of hypodontia: background and role of paediatric dentistry. Br Dent J 2003;194:245–51. 2. Hobson RS, Carter NE, Gillgrass TJ, et al. The interdisciplinary management of hypodontia: the relationship between an interdisciplinary team and the general dental practitioner. Br Dent J 2003;194:479–82. 3. Worsaae N, Jensen BN, Holm B, et al. Treatment of severe hypodontiaoligodontia-an interdisciplinary concept. Int J Oral Maxillofac Surg 2007;36:473–80. 4. Creton M, Cune M, Verhoeven W, et al. Implant treatment in patients with severe hypodontia: a retrospective evaluation. J Oral Maxillofac Surg 2010;68:530–8. 5. Nystrom E, Nilson H, Gunne J, et al. A 9-14 year follow-up of onlay bone grafting in the atrophic maxilla. Int J Oral Maxillofac Surg 2009;38:111–6. 6. Quiles JC, Souza FA, Bassi AP, et al. Survival rate of osseointegrated implants in atrophic maxillae grafted with calvarial bone: a retrospective study. Int J Oral Maxillofac Surg 2015;44:239–44. 7. Durey K, Carter L, Chan M. The management of severe hypodontia. Part 2: bone augmentation and the provision of implant supported prostheses. Br Dent J 2014;216:63–8. 8. Cawood JI, Howell RA. A classification of the edentulous jaws. Int J Oral Maxillofac Surg 1988;17:232–6. 9. Hallman M, Thor A. Bone substitutes and growth factors as an alternative/complement to autogenous bone for grafting in implant dentistry. Periodontol 2000 2008;47:172–92. 10. Felice P, Pistilli R, Barausse C, et al. Short implants as an alternative to crestal sinus lift: A 1-year multicentre randomised controlled trial. Eur J Oral Implantol 2015;8:375–84. 11. Xie C, Lu H, Li W, et al. The use of calcium phosphate-based biomaterials in implant dentistry. J Mater Sci Mater Med 2012;23:853–62. 12. Aghaloo TL, Moy PK. Which hard tissue augmentation techniques are the most successful in furnishing bony support for implant placement? Int J Oral Maxillofac Implants 2007;22(suppl):49–70. 13. Bohner M, Gbureck U, Barralet JE. Technological issues for the development of more efficient calcium phosphate bone cements: a critical assessment. Biomaterials 2005;26:6423–9. 14. Deeb GR, Laskin DM, Deeb JG. Simultaneous impacted third molar extraction and lateral ramus block graft harvest for horizontal ridge augmentation: A case series. J Oral Maxillofac Surg 2017;75:509–13. 15. Katsuyama H, Jensen SS. Sinus floor elevation procedures, vol 5. ITI Treatment Guide. New Malden: Quintessence Publishing Company; 2011.
Please cite this article in press as: Breeze J, et al. Success rates and complications of autologous onlay bone grafts and sinus lifts in patients with congenital hypodontia and after trauma. Br J Oral Maxillofac Surg (2017), http://dx.doi.org/10.1016/j.bjoms.2017.08.001