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Purpose: Multiple bone augmentation techniques are available to allow implant placement in the atrophic maxilla. However, questions remain, regarding which methods are most predictable and have the best dental implant survival rate (SR) in grafted bone. The aim of this systematic review was to evaluate literature from the last 30 years to determine predictability of bone grafting of the edentulous maxilla for implant placement as well as for implant SR., Materials and Methods: A systematic review was performed of studies conducted during the period 1980 to 2014, specifically focusing on the edentulous maxilla and bone grafting. Surgical techniques discussed in the publications included were guided bone regeneration (GBR), sinus augmentation, onlay bone grafting, nasal floor grafting, and Le Fort I interpositional grafting. All identified articles were evaluated and screened to meet strict inclusion criteria of at least 10 patients, complete maxillary edentulism, 1-year follow-up, and information regarding implant SR. A total of 974 articles were identified with electronic and manual searches. On further evaluation of the titles and abstracts, 44 articles were excluded. Full texts of the articles that met the inclusion criteria were reviewed, of which 40 articles were included in the systematic review., Results: For onlay bone grafting, 16 studies were included and analyzed, and the weighted mean implant SR was 85.2%. For the GBR technique, two studies were included, with a reported SR ranging from 96.1% to 100%. For Le Fort I interpositional grafting, 11 studies were included, with a weighted mean SR of 89.6%. For the sinus augmentation technique, 12 studies were investigated and the weighted mean SR was 91.5%. For the combination technique, six studies were analyzed and the weighted mean SR was 93.6%., Conclusions: All five treatment modalities discussed-onlay bone grafting, GBR, Le Fort I interpositional grafting, maxillary sinus augmentation, and/or nasal floor inlay grafting or the combination approach-can be successfully used to augment edentulous maxillary ridge with high implant SRs.

Purpose: This case report documents the histological, histomorphometric, and radiographic effects of a new radiated-preserved bone allograft for sinus elevation procedures., Materials and Methods: This unique bone substitute differs from other forms of bone allograft processed through the standard cryopreservation method. Histology from bone biopsy core samples revealed newly formed bone with a well-organized lamellar bone structure in general and remaining particles were observed in contact with surrounding newly-formed bone., Results: Histomorphometric results demonstrated an average new bone formation of 31.8%. Radiographic linear data demonstrated an 8.49% +/- 6.77% graft resorption from baseline to 6 months., Conclusion: The outcome of this report suggests that this bone allograft could be successfully used in sinus lifting procedures. It encourages further research of this radiated-preserved bone allograft material in oral and maxillofacial reconstruction.

Symphysis graft procedures are being performed in clinical practice more frequently than ever before. Convenient surgical access, proximity of donor and recipient sites, low morbidity, availability of larger quantities of bone over other donor sites, minimal resorption, no hospitalization, and minimal discomfort are some advantages of this procedure over other intraoral sites. Three types of horizontal incisions can be performed during this procedure: the sulcular, the marginal, and the alveolar mucosal. Most studies regarding the chin graft technique are more concerned with the bone graft aspect than soft tissue management. Moreover, the criteria for the selected flap design appear to be based primarily on clinical experience or the same surgical approach regardless of interfacing factors. The periodontal status, amount of bone loss, periodontal risk of root fenestration, amount of keratinized gingiva, restorations in the gingival margin, and local musculature are some of the clinical findings that should be assessed to indicate the best incision design. In this review article, the advantages, disadvantages, indications, and contraindications of each incision design will be discussed.

Cortical bone grafts harvested from the posterior mandible offer several advantages for bone augmentation prior to implant placement. These grafts maintain their dense quality and exhibit minimal resorption upon incorporation. Considerable amounts of bone can be harvested from this area for use as an onlay graft. In addition, the ramus area has some inherent advantages over other donor sites. This article describes the indications and surgical technique for harvesting bone from the ramus region.

This article describes the fabrication of a surgical template for planning and performing the harvest and placement of autologous bone grafts for the reconstruction of alveolar defects before implant placement. A diagnostic cast is altered to replicate the anticipated bone anatomy. The ideal bony contours for implant placement are then created on the cast to form the template. This template may then be used for treatment-planning donor sites for the harvest of corticocancellous bone grafts. The template is sterilized and used by the surgeon in procuring and placing the bone graft. This template allows communication of the prosthetic requirements of the ridge augmentation, as well as ensuring adequate volume and proper positioning of the block graft for eventual implant placement.

The contour of the residual ridge is reduced within 1 year by approximately 25% in width after the extraction of a natural tooth. The augmentation of a tooth socket after an extraction decreases the loss of available bone width for an endosteal implant. Grafting at the same time as the extraction has benefits from both a patient and doctor perspective. However, primary closure is more difficult, and may require the facial keratinized gingiva to be undermined and approximated on the crest of the ridge, or the use of membranes, which are exposed during the soft tissue healing. The modified socket seal surgery uses a technique described by Landsberg and couples his procedure with autologous bone harvested from the maxillary tuberosity. As a result, the tooth extraction socket may be augmented with autologous bone and connective tissue with a simplified approach at the same time as the extraction of a tooth.

Fifty patients with inadequate bone volume for implant placement were treated with mandibular bone grafts from the symphysis or ramus. The choice of donor site was determined by defect morphology and recipient site location. Although the harvest of bone was associated with low morbidity, the ramus donor site resulted in fewer complications. Implants were placed secondarily following a 4- to 6-month healing period. The onlay grafts exhibited minimal resorption and maintained their dense quality. The symphysis grafts were larger in overall volume, with a corticocancellous morphology. The ramus area provided essentially a cortical graft that was well suited for veneering ridge deficiencies; however, the surgical access in some cases was more difficult than in the anterior mandible.

This article describes the fabrication of a bur guide surgical template for implant placement in grafted jaws. This surgical template makes use of the disposable titanium implant mounts packaged for implant insertion. The bur guide allows not only for communication of the implant position but for its ideal trajectory as well. It is applicable in cases where adequate bone volume for implant placement is expected, for example, following autogenous bone grafting.

Local bone grafts are a convenient source of autogenous bone in alveolar reconstruction. The mandibular ramus area provides primarily a cortical graft that is well-suited for veneer-grafting of ridge deficiencies prior to implant placement. The advantages of this method of augmentation include its intraoral access and low morbidity. Similar to bone harvested from the mandibular symphysis, these grafts require short healing periods, exhibit minimal resorption, and maintain their dense quality. Advantages of this donor site over the chin include minimal patient concern for altered facial contour, proximity to posterior mandible recipient sites, and decreased complaints of postoperative sensory disturbances and discomfort. However, the surgical access in some cases is limited, and there is a potential for damage to the mandibular neurovascular bundle. The learning objective of this article is to review and update the reader knowledge of alveolar ridge augmentation using mandibular grafts.

Severe alveolar deficiencies can prevent ideal implant placement. Management of osseous defects often necessitates autogenous bone grafting. The mandibular symphysis graft technique offers ease of access, good bone quantity for localized repair, a corticocancellous block graft morphology, low morbidity and minimal graft resorption. An improved bone density results along with a shorter healing time as compared with other methods for bone repair. An understanding of graft management and implant placement is essential for clinical success.

This case report demonstrates the interface histology of hydroxyapatite-coated dental implants placed in a human vascularized iliac bone graft. Microscopic evaluation found a direct contact of lamellar bone to the implant surface even in areas of loose trabeculation. The hydroxyapatite coating was intact, with no evidence of resorption. This study appears to show that the healing response to hydroxyapatite-coated implants placed in vascularized bone grafts is similar to previously reported findings in nongrafted sites.

Autogenous grafts in conjunction with endosteal implants may be indicated in conditions of severe atrophy of the maxilla. From July, 1984, to December, 1990, 20 severely atrophic arches were restored with iliac crest onlay block grafts, subantral augmentation, and 148 endosteal root-form implants. Twenty-one implants were placed at the same time as the graft to stabilize a corticotrabecular bone block. Two implants were lost (90% implant survival). One hundred twenty-seven implants were placed after graft maturity, and one implant was removed (99% implant survival). Thirteen fixed restorations and 7 completely implant-supported overdentures were fabricated. Follow-up evaluation of prostheses and implants ranged from 26 to 97 months. All the implants used for initial prosthesis fabrication and all initial prostheses remain in function. The advantages of implant placement after graft maturity and subantral augmentation are addressed. One year after implant placement, the amount of additional bone lost around the implants placed in grafted bone is similar to the bone loss around maxillary implants inserted into non-grafted bone.

There are three classes of bone-grafting materials based upon the mode of action. Autogenous bone is an organic material and forms bone by osteogenesis, osteoinduction, and osteoconduction. Allografts such as demineralized freeze-dried bone are osteoinductive and osteoconductive and may be cortical and/or trabecular in nature. Alloplasts such as hydroxyapatite and tricalcium phosphate may be synthetic or natural, vary in size, and are only osteoconductive. They can be divided into three types based upon the porosity of the product and include dense, macroporous, and microporous materials. In addition, alloplastic materials may be crystalline or amorphous. These materials have different properties and therefore indications. The use of the three classes of materials in diverse combinations depends upon the size and topography of the bony defect. Small defects or defects with four walls of host bone can be repaired with alloplasts alone or allografts in combination with alloplasts. The loss of three or more bony walls mandates the addition of autogenous bone to the graft or the use of a small pore membrane. The larger the defect, the more autogenous bone is required. The different indications of bone substitutes are discussed as to their specific applications in implant dentistry.

Partially edentulous patients with alveolar defects contraindicating implant placement were treated with bone grafts obtained from the mandibular symphysis. Complications encountered were minor and uneventful. Evaluation 4 months after surgery revealed minimal graft resorption, thus implant placement was possible in all potential sites. Advantages of the symphysis graft include easy access, availability of greater quantities of bone over other intraoral donor sites, low morbidity, no hospitalization, minimal discomfort, no alteration in ambulation, and no cutaneous scar. Compared with other bone regenerative methods for implant placement, a superior quality of bone was found and a shorter healing period is required. Results of this preliminary clinical investigation demonstrate that chin grafts offer a viable alternative for reconstruction of alveolar defects prior to dental implant placement.

The use of autogenous bone grafts (ABG) combined with endosteal implants permits to restore patients with conditions of extreme bone atrophy or with very demanding final results. The improvement of the biomechanics conditions, moment forces, C/I ratio, ridge relationship, length, diameter, number and location of the implants and esthetics improve the prognosis of the restoration. Large segments of autogenous bone is harvested from the iliac crest or cranium. Excellent autogenous membranous bone can be obtained intra-orally from the mandibular symphysis when smaller dimensions are needed. Indications for treatment with autogenous bone grafts are presented following the Misch/Judy available bone classification. In division C-w ridges, ABG improve the width of the ridge to permit the placement of root form implants. In Division C-h ridges, ABG improve the height available for implant placement, and permits to obtain a FP-1 or FP-2 result. In Division D ridges, ABG represent the treatment of choice. RP-4 restorations are encouraged. High success rates obtained by the author depend upon strict patient evaluation, treatment planning, careful placement of the minimum number of implants with the bone grafting procedure only to immobilize the grafted segment, progressive bone loading during the prosthetic phase, proper soft tissue management and sufficient number of implants for the planned prosthesis.