Severely resorbed mandible treated with iliac crest autogenous bone graft and dental implants: 17-year follow-up

Severe bone atrophy in the mandible may result in weakening of the jaw, unstable dentures, and dysfunction of the inferior alveolar nerve. These conditions were diagnosed in a 65-year-old woman who presented with a severely resorbed mandible. The interforaminal region of the mandible was augmented with an onlay graft harvested from the iliac crest. Four dental implants stabilized the graft by anchoring it inferiorly to the residual mandibular basal bone. Implants later served as abutments for a fixed 12-unit implant-supported prosthesis. The patient was followed for 17 years, during which the mandibular prosthesis was replaced twice. Despite the initial questionable prognosis, oral rehabilitation was successful, with no detectable clinical signs of bone loss over the 17-year follow-up period.     

Bare bone graft with vascularised iliac crest for mandibular reconstruction

Background

“Bare bone graft” with a vascularised iliac crest is a procedure involving no soft tissue for intraoral lining, and the intraoral defect is covered with epithelial cells through secondary healing of the exposed bone.

Methods

A vascularised iliac crest flap is transferred to a segmental mandibular defect intraorally in the position of the osteotomized stump upwardly. Granulation tissue is usually observed on the stump of the bone graft about 1 week after surgery. When sufficient granulation is observed after approximately 4 weeks, “resurfacing” is performed to prevent interference of hypergranulation tissue with epithelization. Resurfacing involves wiping the granulation tissue from the surface of the bone and covering with a plastic prosthesis fitted to the alveolus.

Results

A total of 11 patients underwent bare bone graft with a vascularised iliac crest. Resurfacing was performed at an average of 2.1 times for each patient. All wounds in the oral cavity were completely epithelialized from 2 weeks to 3 months after surgery. Complications with the recipient side occurred in four patients.

Conclusions

Bare bone graft with the iliac crest is one favourable option for mandibular reconstruction utilising the particular shape of the bone without the attached soft tissue.     

Non-vascularised iliac crest bone graft for immediate reconstruction of lateral mandibular defect

Introduction

Mandibular defect reconstruction is extremely important to achieving an improved quality of life of patients as this bony defect influences facial harmony and aesthetics. Reconstruction of mandibular defects at our centre comprises use of reconstruction plate, non-vascularised anterior iliac crest graft and vascularised fibula flap. Despite the large mandibular defect recorded in our developing environment, non-vascularised iliac crest graft continues to play a role in its exclusive use for lateral mandibular defects. The aim of this study was to analyse the role, complications and outcomes of the use of non-vascularised iliac crest graft for mandibular reconstruction in a free flap-enabled centre.

Patients and method

This was a retrospective case cohort from study institution’s records of mandibular reconstruction following mandibular surgery for benign tumours. Eligibility for study inclusion comprised case cohort with head and neck diseases requiring mandibular surgery and reconstruction with either reconstruction plate, non-vascularised iliac crest graft or vascularised fibula flap.

Results

A total of 18 subjects underwent iliac crest grafting. Of the 18 subjects with iliac crest graft, 7 (39 %) were females while 11 (61 %) were males. Ten of the 18 subjects with iliac crest grafting were diagnosed with ameloblastomas. Six (33.3 %) subjects had class H (Jewer’s classification) mandibular defect. The average graft length was 5.4 cm and height was 2.3 cm. Three cases experienced graft site complications of which two grafts were lost. All 18 cases experienced good to acceptable clinical outcomes. Predictors of graft outcome were not statistically significant.

Conclusion

Despite our small sample size, it is suggestible that non-vascularised iliac crest graft be considered for lateral mandibular defect reconstruction, considering the reduced graft failure rate and satisfactory clinical outcomes from this study.

     

Morbidity from iliac crest bone harvesting

The iliac crest is the most common donor site for autogenous bone grafting in maxillofacial surgery. The aim of this study was to evaluate retrospectively the morbidity of bone harvesting from the inner table of the anterior iliac crest. Sixty-five patients were recalled 1 to 4 years after iliac crest bone harvesting. The morbidity as well as the patient's satisfaction were evaluated by a survey of the medical record, a mail-in questionnaire, and a standardized physical examination. There was good acceptance of this bone harvesting procedure, and the morbidity was low. Bone harvesting from the inner table of the anterior iliac crest is a good option for reconstructing bone defects.     

Quadruple zygomatic implants supported rehabilitation in failed maxillary bone reconstruction

Extreme atrophy of the jaws constitutes a challenge for maxillofacial surgeons. The technique involving Le Fort I osteotomy, bone grafting, and endosseous implants remains the gold standard treatment for class V and class VI atrophy of the maxilla. As severe maxillary atrophy is associated to impaired microvascularization of overlying soft tissues, reconstruction using vascularized free fibula flaps together with endosseous implants is one of the possible treatment plans. When this approach fails, however, retreating these patients using traditional techniques often proves unsatisfactory. This study outlines our clinical experience with full-arch zygoma implant-supported prosthetic rehabilitation to treat severe atrophic maxilla following failure of strategies including multiple Le Fort I procedures or vascularized free fibular flaps.     

In-office iliac crest bone harvesting for peri-implant jaw reconstruction

We describe 2 minimally invasive techniques for in-office iliac crest bone harvesting. The increasingly limited access to hospital operating rooms and the increased need for bone grafting to facilitate dental implant-related reconstructions have been the major impetuses behind relocating some of these surgeries to the out-of-hospital, in-office setting.     

实验性骨质疏松对种植体周自体骨移植愈合影响的研究

目的研究实验性骨质疏松（OP）对兔种植体周自体骨移植愈合的影响。方法将20只雌性日本大耳白兔随机分成对照组和实验组,实验组行双侧卵巢切除术,对照组接受假手术。术后12周测量股骨骨密度（BMD）,证实OP状态。同时在2组家兔左侧胫骨近中干骺端制备骨缺损,行自体髂骨移植和同期种植体植入手术。植骨术后第8、12周分2批处死动物,切取标本制作不脱钙硬组织切片,进行组织形态学观察和骨计量学检测。结果实验组BMD显著低于对照组（P<0.001）,证实OP造模成功。植骨术后第8、12周,种植体在2组植骨区均达到了骨结合。然而,实验组植骨区内骨皮质厚度（TCB）、松质骨区骨量（BVC）、种植体骨结合率（IBCR）均显著低于对照组（P<0.01）,且新生骨量也明显少于对照组。结论实验性OP虽然不会延迟自体骨移植内种植体骨结合,但可促进植骨吸收,减少BVC,降低IBCR。因而,对于行自体骨移植同期牙种植的患者,OP是一个重要的危险因素。     

Tooth autotransplantation in a free iliac crest graft for prosthetic reconstruction

This report documents successful tooth autotransplantation to a free iliac crest graft in an exemplar case. A 14-year-old male patient was operated thrice with increasing amounts of resection for recurrent odontogenic myxoma. When mandibular continuity resection finally was performed, a free iliac crest block autotransplant was used for reconstruction. Upon metal removal 5 months later, 3 wisdom teeth with two-thirds complete root development were transplanted to the free graft and retained by fixed orthodontic appliances including skeletal anchorage with orthodontic microscrews. Tooth graft taking was awaited for 8 weeks with retention. Following undisturbed healing without occlusal forces, 6 months of orthodontic treatment intentionally extruded the autotransplanted teeth to antagonist contact. The third and most dorsal tooth became mobile after 3 months and was lost. The surviving 2 teeth were fitted by a prosthetic bridge as extrusion into the occlusal plane was not completely successful. This exemplar case shows benefit of tooth autotransplants in selected cases of jaw reconstruction with distal bone autotransplants as alternative to dental titanium implants and suprastructures. Orthodontic microscrews can moreover support tooth movement and positioning as anchorage device in altered anatomy.     

Calvarial versus iliac crest for autologous bone graft material for a sinus lift procedure: a histomorphometric study

PURPOSE: The aim of this study was to compare, through histomorphometric analysis, the use of donor autogenous bone graft from calvarial or iliac sources for maxillary sinus lift procedures. MATERIALS AND METHODS: Sixteen patients requiring maxillary sinus augmentation were included in this study. One group of 10 patients was alternatively selected to receive autologous calvarial bone particles, and another group of 6 patients received autologous iliac bone particles. Five months after surgery, bone biopsy specimens were obtained at the time of implant procedure and analyzed through histomorphometry. To compare mean values between the calvarial and iliac crest groups, the Student t test was performed. The level for statistical significance was set at P < .05. RESULTS: All patients completed the healing period following sinus augmentation procedure without complications. In the calvarial group, an average total bone volume (BV) of 73.4% +/- 13.1% was found. Nonvital bone constituted an average of 5.5% +/- 6.3% of the total tissue volume. The percentage of vital bone (VB) showed an average of 67.9% +/- 16.1%. In the iliac group, the average total bone volume was 46.6% +/- 17.4%, with an average of 12.6% +/- 7.7% of NVB and an average of 34.0% +/- 21.5% of VB. A significant difference was observed between calvarial and iliac bone grafts with respect to BV, VB, and NVB (P < .05). CONCLUSION: From this present histomorphologic study, it might be concluded that grafted bone obtained from calvarial sources for sinus lift procedure presented a significantly higher degree of bone volume and vital bone volume in contrast to bone harvested from the iliac crest.     

自体髂骨游离移植加同期种植修复牙槽缺损初步观察

目的：利用自体髂骨游离移植同期种植修复牙槽缺损。方法：13例牙槽嵴萎缩患者行自体髂骨游离移植同期植入29枚种植体。结果：移植骨存活，植入的29枚种植体与移植骨结合良好，义齿修复一年后种植体无松动、脱落。结论：采用该方法可早期修复牙槽缺损，但仍需进一步观察长期效果。     

An investigation of post-operative morbidity following iliac crest graft harvesting

OBJECTIVE: A study which examined the morbidity experienced by patients who underwent iliac crest bone graft procedures. DESIGN: A post-operative questionnaire was forwarded to patients who underwent iliac crest bone graft procedures at a single centre. SUBJECTS: One hundred and fourteen patients underwent iliac crest bone grafts for intra-oral augmentation. RESULTS: Ninety-eight patients (80%) returned post-operative questionnaires. Eighty of the 98 (81.6%) patients suffered post-operative pain with 70% of patients being pain-free after four weeks. However, 10% of patients experienced pain for more than 16 weeks. Eighty-five (86.7%) patients were able to walk without any difficulties six weeks post-operatively. Gait disturbance was not related with age, however there was a significant association between pain and disturbance of gait (P< 0.001). Twenty two patients required the use of a walking stick and the use of such aids varied from 0.5 to 26 weeks. Women used walking aids for longer periods than men (P< 0.05). Twenty five patients had altered sensation with about half of them experiencing altered sensation in the distribution of the lateral femoral cutaneous nerve. Other morbidities included deformity at the hip site (2.4%), haematoma (2.4%), infection (3.2%), stress fracture (4.1%) and meralgia paraesthetica in one patient. Despite the above morbidities, 82 patients were willing to undergo the same procedure again and 89 patients would recommend the procedure to their relatives and friends. CONCLUSION: This study demonstrates considerable morbidity following anterior iliac crest bone harvest for intra-oral augmentation. Clinicians referring patients for such bone graft procedures must be aware of the above morbidities so that any patients referred for such procedures are fully informed.     

The zygomatic implant: preliminary data on treatment of severely resorbed maxillae. A clinical report

The Br?nemark Zygomaticus implant was used in conjunction with premaxillary standard implants for the reconstruction of resorbed edentulous maxillae. A total of 44 zygomatic implants and 80 premaxillary implants were placed in 22 patients. All implants were stabilized at phase II surgery using a rigid bar. After soft tissues had healed, implant-supported fixed prostheses were fabricated. This article presents a preliminary report on 22 patients followed for 34 months, with a 100% success rate for the zygomatic implants and a 91.25% success rate for the premaxillary implants.     

Anatomic site evaluation of the zygomatic bone for dental implant placement

Thirty human zygomatic bone specimens (15 females mean age 81.60 +/- 11.38 years, 15 males, mean age 78.47 +/- 6.58 years) were examined by quantitative computed tomography and histomorphometry. The aim of the study was to assess the bone mineral density, the trabecular bone volume and the trabecular bone pattern factor. Moreover, the anterior-posterior and the medio-lateral dimensions and the estimated implant length within the zygomatic bone were determined. For quantitative computed tomography the specimens were scanned together with a bone mimicking anthropomorphic reference phantom. The bone mineral density was calculated for the specimens in the plane of the intended direction of the implant placement. Subsequently, with the sawing and grinding technique, the specimens were prepared in the same plane for histomorphometry. The trabecular bone mineral density was 369.95 +/- 188.80 mg/cm3 for the female and 398.94 +/- 99.11 mg/cm3 for the male specimens (P = 0.23). The male trabecular bone volume showed a value of 27.32 +/- 9.49%, while the female group reached a value of 19.99 +/- 7.60% (P = 0.23). The trabecular bone pattern factor was 1.2 x 10-2 +/- 1.28 mm-1 for the male and 1.02 +/- 0.96 mm-1 for the female specimens (P = 0.045). The study reveals that the zygomatic bone consists of trabecular bone with parameters that are unfavourable for implant placement. However, the success of implants placed in the zygomatic bone is secured by the employment of at least four cortical portions.     

Mandibular ameloblastoma. Reconstruction with iliac crest graft and implants

The ameloblastoma is a bening odontogenic tumor. The treatment planning in young persons is still not clear. We describe a case report of a young boy who was treated in our unit and we review the different approaches for this type of lesions, which nowadays still not clear in this patients.     

Use of the trephine for harvesting bone from the iliac crest

For closure of the cleft alveolus usually a choice between a bone graft from the chin or from the iliac crest is made. In the department of Oral and Maxillofacial Surgery of the University Hospital Groningen harvesting of bone from the iliac crest was performed with an open technique. From the results of an earlier study on the morbidity of this procedure until June 1997 it was found that in 26.1% of the cases a contour defect could be observed in the donor region. The mean width of the mature scar was 5.0 +/- 2.4 mm (range 1-10 mm). Especially these findings and the wish to further reduce postoperative pain led the University Hospital to start harvesting iliac crest bone grafts with a trephine in june 1997. In the period june 1997 through december 1999 iliac crest bone grafts were harvested in 28 cleft lip and palate patients (mean age 10.5 years; range 8-12 years) with this trephine technique. The scars were smaller in +/- 0.3 both length (mean 15 +/- 1.5 mm; range 11-24 mm) and width (mean 1.5 +/- 0.3 mm; range 1-3.5 mm). No contour defects and sensory loss occurred. Postoperative pain could adequately be relieved by local infiltration of the donor area with a 0.25% marca?ne solution and analgetics. On the first day post surgery all patients could be mobilised without problems. Based on these findings and recent literature it can be concluded that the use of the trephine is the method of choice for harvesting iliac crest bone in cleft lip and palate patients. Only when large amounts of bone, a bone block or a piece of cortical bone is needed, the open technique should be used.     

Radiologic appraisal of healing after iliac crest bone grafts

Radiographic changes were observed in 45 patients who had undergone iliac bone grafting with either metal or wire fixation after resection of the mandible. Changes were generally not observed during the first month after surgery. Bony resorption was seen during the second or third month. Osteogenesis commenced at any stage, but was usually radiographically evident by 3 to 6 months. Union was not radiographically evident in most cases until more than 6 months had elapsed after surgery. For follow up, plain film radiographs 4 to 6 months after surgery are recommended in patients who receive bone grafts.