Reconstruction of the severely atrophic edentulous mandible by means of autogenous bone grafts and simultaneous placement of osseointegrated implants

A method of reconstructing the severely atrophic mandible that simultaneously provides additional strength and the ability to house osseointegrated implants is presented. The performance of the procedure from an external approach minimizes the possibility of oral contamination and, therefore, infection. The procedure has been performed on 10 patients, with a longest follow-up of 3 years. A 93% success rate has been achieved, and bone resorption at the implant sites has thus far been negligible. Prosthetic rehabilitation has been done in 9 of the 10 cases; 3 have been tissue-supported prostheses, and 6 have been completely implant-supported prostheses.     

Augmentation of the atrophic edentulous mandible by a bilateral two-step osteotomy with autogenous bone graft to place osseointegrated dental implants

Extensive resorption of the mandible increases the interarch space and rehabilitation with traditional dentures is often unsatisfactory due to the superficialization of intraoral muscles. A study of 19 patients who underwent augmentation of an atrophic mandible using a bilateral two-step osteotomy and interpositional bone graft technique is presented. Three horizontal bone cuts (one in the intraforamina and two in the molar region) were made and jointed together by two short vertical bone cuts mesialy to the mental nerve. The cranial fragment was lifted and the iliac bone graft was interposed recreating the correct intermaxillary relationship. A broad vascular pedicle was maintained during surgery, ensuring nutrition from the lingual side, essential to reduce resorption of the bone graft and cranial fragment. 141 Biomet 3i Osseotite^® implants were placed. Patients were rehabilitated with a full-arch implant-supported fixed prosthesis or an implant-supported overdenture. This clinical study describes the resorption process over a 4 year follow-up. 3 of 19 suffered from persistent neurosensitive disturbances. In conclusion, bilateral two-step osteotomy in association with interpositional bone graft is a reliable surgical means to recreate the anatomical morphology of the mandible.     

Dentoalveolar reconstruction of a missing premaxilla using bone graft and endosteal implants

We report here on a patient with bilateral cleft lip and palate (BCLP) and a missing premaxilla, who underwent dentoalveolar reconstruction of the cleft and premaxillary alveolus using endosteal implants after bone grafting. The patient, whose maxillary incisors and premaxilla were missing, had corticocancellous bone grafting from the iliac crest, followed by excellent bone formation at the anterior alveolus. After the placement of the endosteal implants and the completion of the pre-surgical orthodontic alignment, orthognathic surgery was performed for the restoration of a Class III open bite. After post-operative orthodontic preparation, the final fixed prostheses were completed. This treatment procedure offers an option of dentoalveolar reconstruction for BCLP patients with an excised premaxilla.     

Etiology and management of mandibular fractures associated with endosteal implants in the atrophic mandible

Mandibular fractures can occur with the insertion of endosseous implants. Four patients whose mandibles were fractured with the removal or insertion of mandibular endosseous implants are described. Three of the patients required an autogenous bone graft to repair the fracture, and 1 patient was managed with a reconstruction plate. Strategies for prevention and treatment of this uncommon complication are discussed.     

The combined use of two endosteal implants and iliac crest onlay grafts in the severely atrophic mandible by a modified surgical approach

Seventeen patients, who received an iliac crest onlay bone graft augmentation to their severely atrophic mandible with simultaneous placement of two endosteal implants by a modified surgical approach, were studied retrospectively. Follow-up ranged from 0.5 to 7.9 years after implant loading with an average follow-up of 4.3 years. Frequency of wound dehiscences and other postoperative complications, the extend of resorption of the initial graft, and the implant success rate were assessed. Two patients, who had a previous history of preprosthetic and implantological procedures at the surgical site, developed a serious wound dehiscence with loss of two implants in one patient and need for antibiotic treatment and sequestrectomy in the other patient. One implant was lost in two other patients with a negative surgical history, resulting in an implant success rate of 88.2%. The average resorption at the last follow up visit was 15% of the initial graft. Damage of the mental nerve was seen in 14.7% of nerves. Our preliminary data indicate that the procedure presented provides a reliable and predictable method for the construction of an implant-bearing overdenture in patients with a severely atrophic mandible. This one-step procedure can not be recommended for patients with a history of surgery in the anterior mandible.     

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.     

Fibula microvascular free tissue reconstruction of the severely comminuted atrophic mandible fracture--case report.

Severely atrophic comminuted fractures of the mandible often have inadequate bone stock available to allow for adequate rigid fixation and subsequent progression to union. Grafting with rib, iliac crest or a variety of allograft materials is required in order to increase the success rate of the repair in this patient population. In this article, we report our favourable experience in using a fibula microvascular free tissue transfer for the treatment of a particularly challenging patient with a fractured atrophic mandible. Secondary implant rehabilitation completed the reconstruction. This method may represent an alternative in the treatment of fractures of the severely atrophic mandible in select individuals.     

Placement of endosteal implants combined with chin bone onlay graft for dental reconstruction in patients with grafted alveolar clefts

Endosteal implants were inserted into grafted alveoli after particulate cancellous bone and marrow grafting in seven patients with cleft lip or palate in conjunction with simultaneous chin bone onlay grafting. In these patients, the alveolar bone height of the bony bridge was insufficient when evaluated by both computed tomographic and periapical radiographic images. The age at first implant surgery ranged from 14 to 28 years. Although four of the seven patients had an uneventful course, three had wound dehiscence, and in all but one of them the exposed chin bone underwent partial or total necrosis. Ultimately all seven implants integrated into the bone, and the alveolar bone height was increased in all but one patient. The results indicate that chin bone onlay grafting with simultaneous implant insertion is useful in patients with cleft lip or palate with insufficient alveolar bone height.     

Interpositional bone graft augmentation of the atrophic mandible: a preliminary report.

The mandible is sectioned in an oblique direction and an iliac crest graft is placed between the fragments for augmentation of an atrophied mandible. The technique was used in 12 patients; follow-up examinations included serial panoramic radiographs and recording of changes in mandibular height. A 10% to 27% loss of the height gained occurred between three and 12 months postoperatively.     

Stability of bone grafting and placement of implants in the severely atrophic maxilla

A severely atrophic maxilla can be restored by bone grafts to allow the insertion of implants. We present 30 consecutive patients treated with autogenous inlay and onlay bone grafts from the iliac crest to the floor of the maxillary sinus and the alveolar crest. A total of 200 implants were inserted 4-6 months after bone grafting. A mean vertical increase in bone thickness of 14mm was achieved. After a mean bone loss of 1.3mm during the first year after bone grafting only minimal resorption was observed during the second and third year. Seven implants failed to integrate and a further four implants were lost during follow-up.     

A reappraisal of the interposed bone graft augmentation of the atrophic mandible

A follow-up on 148 patients who had undergone an interposed bonegraft augmentation of the atrophic mandible is presented. The first group consisted of 38 patients who underwent surgery 4-6 years ago. The second group of 70 patients has a follow-up period of 3 to 4 years. The third group of 40 patients was followed up from 2 to 3 years postoperatively. The phenomenon of post-operative bone resorption which continues for many years postoperatively, is discussed. The high incidence of nerve disturbances as found in this study is regarded as unacceptable. The dissection of the mandibular nerve out of its canal (decompression) in order to avoid nerve damage during the operation is not found to be of any advantage. A modified technique is recommended to circumvent this problem.     

嵌贴式植骨术在牙槽嵴严重吸收患者牙种植术中的应用

目的:总结嵌贴式植骨方法进行缺牙后重度吸收牙槽嵴骨增量的植骨技术及其效果。方法:15例重度吸收牙槽嵴患者接受了嵌贴式植骨术,分别于植骨12～24周后植入种植体,共植入26枚种植体。术后16～24周行种植体基台连接术及烤瓷冠或烤瓷桥修复。结果:术后12周复诊二期植入种植体者,术中见植骨块吸收很少,所有患者均成功完成了种植修复。15例植骨患者中,3例出现术后感染,但仍获一定程度的骨增量效果,12例无并发症。所有病例修复后追踪24～48周,无种植体脱落。结论:嵌贴式植骨技术应用于严重吸收牙槽嵴骨增量操作简单,效果可靠。     

Free fibula flap for reconstruction of the severely atrophic mandible: a retrospective study

The purpose of this retrospective study was to assess the feasibility of using a free fibula flap (FFF) for reconstruction of the alveolar region of the severely atrophic mandible, by determining bone stability after dental implant insertion and prosthetic rehabilitation in a series of eight female patients aged 36–65 years. Dental implant insertion was performed 3–4 months after reconstruction. Prosthetic loading was performed 3–4 months after implant insertion. The height of the reconstructed mandible after surgery was 21.20 ± 1.87 mm, with an increase of 8.80 ± 1.71 mm from the preoperative height. The height of the FFF immediately after reconstruction was 11.24 ± 1.10 mm; this showed a vertical loss of 0.99 ± 0.52 mm (8.79%) and maintenance of 91.21% of the initial height at a mean 14 months post-reconstruction. Applying the Wical and Swoope formula to estimate the original mandibular body height, it was found that the difference between this calculated height (21.17 ± 3.76 mm) and the reconstructed height (21.20 ± 1.87 mm) was only 0.03 ± 3.17 mm (0.14%). An overall insignificant decrease of 0.46 ± 1.14 cm³ in FFF volume had occurred at 3–4 months after dental implant functional loading, while in two cases an increase in volume was found (1.22 cm³ and 1.71 cm³). The good and stable results obtained show that the FFF may be used to reconstruct the whole mandibular alveolar region, with the best possible outcomes.     

Endosseous cylinder implants in severely atrophic mandibles.

A retrospective study was completed to assess the success rate of endosseous cylinder implants placed in mandibles that were 10 mm or less in maximum anterior height as measured from lateral cephalometric radiographs. Only implants that were located anteriorly between the mental foramina and loaded prosthetically for a minimum of 1 year were studied. Twenty-eight patients with a total of 130 Nobelpharma implants (forty-six 7 mm and eighty-four 10 mm) were included. The fixtures were evaluated following standard clinical criteria for success established for implants of this type. A total of 8 (two 7 mm and six 10 mm) of 130 implants failed, yielding an overall success rate of 94%. Major complications encountered included a complete mandibular fracture, a partial mandibular fracture, and a temporary bilateral mental nerve hypoesthesia.