Vertical alveolar ridge augmentation by means of a titanium mesh and autogenous bone grafts

The aim of this study is to evaluate a surgical protocol for vertical ridge augmentation in the maxilla and mandible using autogenous onlay bone graft associated with a titanium mesh. A group of 18 partially edentulous patients, presenting the need for vertical bone augmentation of at least 4 mm, were treated before implant placement. During the first surgery, an autogenous bone graft was harvested from either the mandibular ramus or the mental symphysis and secured by means of titanium screws. Particulate bone was added and a titanium micro-mesh was used to stabilize and protect the graft. After a mean interval of 4.6 months, meshes and screws were removed and 37 endosseous implants were successfully placed. The desired bone gain was reached in all patients. Mean vertical bone augmentation obtained was 4.8 mm (range 4-7 mm). No major complications were recorded at recipient or donor sites. Abutment connection was carried out 2-3 months after implant placement. No implant was lost. Clinical parameters and probing depth, after prosthetic reconstruction, demonstrated the presence of a healthy peri-implant mucosa. The preliminary results suggest that, by using the presented technique, patients can be successfully rehabilitated by means of implant-supported prosthesis 6-7 months after the first surgery, even in case of severely atrophied maxilla.     

Maxillary sinus floor augmentation using bioactive glass granules and autogenous bone with simultaneous implant placement. Clinical and histological findings

This clinical study was undertaken to: 1) evaluate the use of bioactive glass Biogran combined with autogenous bone as grafting material for maxillary sinus augmentation with simultaneous implant placement using radiography and histology; and 2) document the short-term post-loading success of implants inserted in sinus cavities augmented with this material. Unilateral or bilateral sinus augmentation was performed in 12 patients with 3-5 mm of alveolar crestal bone height in the posterior maxilla prior to grafting. The sinuses were grafted with bioactive glass mixed in a 4:1 ratio with autogenous bone. Simultaneously, 2-3 threaded titanium implants were inserted into the augmented sinuses. Second stage surgery was carried out 9 to 12 months post implantation. At abutment connection, 10 core biopsy specimens were taken from different grafted sites and evaluated histologically. All 27 implants were clinically stable at second stage surgery. A mean increase in mineralized tissue height of 7.1 +/- 1.6 mm was evident when comparing the pre-surgical CT scans with those performed 9-12 months following the sinus augmentation procedure. Evaluation of the cores yielded a mean of 30.6 +/- 5.7% of bone tissue in the grafted sites. One implant failed during the prosthetic phase while the remaining 26 implants were stable 12 months post loading. This study suggests that Biogran/autogenous bone graft combination used in one-stage sinus augmentation yields sufficient quality and volume of mineralized tissue for predictable simultaneous implant placement in patients with 3-5 mm of bone height prior to grafting.     

Two-stage reconstruction of the severely deficient alveolar ridge: bone graft followed by alveolar distraction osteogenesis

Distraction osteogenesis for the augmentation of severe alveolar bone deficiency has gained popularity during the past two decades. In cases where the vertical bone height is not sufficient to create a stable transport segment, performing alveolar distraction osteogenesis (ADO) is not possible. In these severe cases, a two-stage treatment protocol is suggested: onlay bone grafting followed by ADO. An iliac crest onlay bone graft followed by ADO was performed in 13 patients: seven in the mandible and six in the maxilla. Following ADO, endosseous implants and prosthetic restorations were placed. In all cases, the onlay bone graft resulted in inadequate height for implant placement, but allowed ADO to be performed. ADO was performed to a mean total vertical augmentation of 13.7 mm. Fifty-two endosseous implants were placed. During a mean follow-up of 4.85 years, two implants failed, both during the first 6 months; the survival rate was 96.15%. In severe cases lacking the required bone for ADO, using an onlay bone graft as a first stage treatment increases the bone height thus allowing ADO to be performed. This article describes a safe and stable two-stage treatment modality for severely atrophic cases, resulting in sufficient bone for implant placement and correction of the inter-maxillary vertical relationship.     

Reconstruction of the severely resorbed (Class VI) jaws: routine or exception?

After disappointing results with conventional preprosthetic procedures endosseous implants in combination with alveolar ridge augmentation opened up new prospects in reconstructive surgery. A total of 64 patients who underwent three-dimensional reconstruction of the alveolar ridge and insertion of endosseous implants for severe resorption were evaluated retrospectively. Despite the postoperative infection rate of 20.3% (13 patients), only 4.1% of the 266 inserted implants were lost in the long term. This indicates that augmentation using free autogenous iliac bone grafts and implants have a success rate of approximately 96% despite difficult initial situations. This success was mainly related to the soft tissue condition covering the graft. A technique for soft tissue dissection, especially in the maxilla, is presented.     

Use of horizontal alveolar distraction osteogenesis for implant placement in a narrow alveolar ridge: a case report

Although alveolar distraction is a promising method for ridge augmentation involving the atrophic maxilla or mandible for implant placement, techniques of horizontal and oblique alveolar distraction for expanding a narrow alveolar ridge have not been established. A case of horizontal alveolar distraction for implant placement using a titanium mesh plate and a distraction screw is reported. Horizontal alveolar distraction was performed on a patient with an extremely atrophic alveolar ridge in the anterior mandibular region. Two transport segments using horizontal osteotomies were prepared, and 2 horizontal alveolar distraction devices were inserted. After a 7-day waiting period, the devices were activated and alveolar widening was performed labially (0.225 mm twice a day for 14 consecutive days). Three months after consolidation, the distraction devices were removed. The distracted areas were completely filled with newly formed solid bone tissue. Two months after the device was removed, 4 endosseous implants were placed and an implant-supported definitive prosthesis was placed. This method of horizontal alveolar distraction appears to be clinically useful for the placement of implants in atrophic or knife-edged alveolar ridges.     

Augmentation of the maxillary sinus floor and alveolar ridge for placement of endosseous implants in the edentulous maxilla

Placement of endosseous implants in the atrophic maxilla is often restricted because of lack of supporting bone limiting placement of implants of adequate length in a prosthodontically optimal position. There are several surgical procedures to create sufficient volume of bone for the placement of implants. In this paper, a technique is described for augmentation of the maxillary sinus floor and simultaneous widening of the alveolar crest with autogenous bone.     

Histologic and histomorphometric evaluation of alveolar ridge augmentation using bone grafts and titanium micromesh in humans

BACKGROUND: Recently, the use of titanium micromesh for alveolar bone augmentation has drawn interest; however, only limited histologic data are available on the quality of the bone regenerated. Therefore, this study compared the use of 100% intraoral autogenous bone to a combination of intraoral autogenous bone (70%) and bovine porous bone mineral (BPBM) (30%) for alveolar ridge augmentation with titanium micromesh histologically and histomorphometrically. METHODS: Twelve partially edentulous patients required alveolar bone augmentation before implant insertion because of ridge resorption. The defect sites, six in the maxilla and six in the mandible, were reconstructed with particulate autologous bone (control group, N = 6) or a mixture of autologous bone and BPBM (test group, N = 6) in combination with titanium micromesh. Core biopsies were taken from the defect sites 8 to 9 months after grafting at the time of implant insertion. RESULTS: Newly formed compact bone with a well-organized lamellar pattern was identified in all specimens. In the samples taken from the test group, the BPBM particles were surrounded completely by newly formed bone with no signs of resorption. The mean total bone volume was 62.38% +/- 13.02% in the control group and 52.88% +/- 11.47% in the test group. The soft tissue volume was 37.61% +/- 13.02% and 29.96% +/- 12.58%, respectively, and the residual BPBM volume was 17.15% +/- 2.72% in the test group. No statistical difference was observed in the histologic parameters evaluated, irrespective of graft type and site (P >0.05). CONCLUSION: Within the limits of this study, BPBM (30%) in combination with autogenous bone (70%) did not yield a lower percentage of new bone formed compared to autogenous bone alone in ridge augmentation with titanium micromesh.     

Histomorphometric analysis of natural bone mineral for maxillary sinus augmentation

PURPOSE: Lack of bone height in the posterior maxilla often necessitates augmentation prior to or simultaneously with dental implant placement. The purpose of this clinical study was to evaluate the use of the natural bone mineral Bio-Oss alone or in combination with autogenous bone in sinus floor elevations performed as 1- or 2-step procedures. MATERIALS AND METHODS: Thirty-eight patients required sinus augmentation. Natural bone mineral alone was used in sinus floor augmentation in 21 patients. In 13 patients, a mixture of the bone substitute and autogenous bone was used, and in 4 patients autogenous bone alone was used. In all of the patients, samples were taken for biopsy 3 to 8 months postoperatively, and bone regeneration was evaluated histologically and histomorphometrically. RESULTS: In all patients, the amount of new bone significantly increased over the observation time, while marrow areas decreased. There was no statistically significant difference in the amount of new bone formation between the Bio-Oss group (new bone 29.52% +/- 7.43%) and the Bio-Oss/autogenous bone group (new bone 32.23% +/- 6.86%). In the 4 patients treated with autogenous bone alone, a greater amount of newly formed bone was found; however, in these cases the area volume filled was smaller than in the other 2 groups. DISCUSSION: The data showed that new bone formation takes place up to 8 months after sinus floor elevation and that there is no difference in the amount of bone formation between procedures done with the bone substitute alone or with the mixture of the substitute and autogenous bone. CONCLUSION: These data suggest that predictable bone formation can be achieved with the use of Bio-Oss.     

Peri-implant conditions in periodontally compromised patients following maxillary sinus augmentation. A long-term post-therapy trial

Augmentation of the maxillary sinus in the atrophied edentulous posterior maxilla is an integral part of implant prosthodontics. This study examined the clinical outcome in 50 periodontally compromised successfully treated subjects with severe maxillary atrophy following oral implantation with Bråemark. IMZ or Frialit-2 endosseous implants between 1991 and 1994. Simultaneous sinus augmentation was achieved using auto-genous bone grafts harvested from the anterior mandible. Oral implants in 37 periodontally healthy patients directly placed in the stable local maxillary bone served as controls. The oral rehabilitation included implant supported restorations or removable superstructures over a period between 3 and 5 years. The peri-implant status of implant abutments inserted in the periodontal compromised augmented maxilla resulted in values comparable to the local maxillary bone except for the GCF rates with enhanced levels of 63.9±49.9 (controls 37.9±40.7). The average peri-implant Periotest values in the augmented maxillary sinus (test group) were ?3.1 PT and +0.2 PT in the controls. The Periotest scores in the sinus area ranked between ?7.0 and +5.0 with mean PT values of ?1.5 for IMZ, ?3.2 for Bråemark and ?4.0 for Frialit-2 abutments. The functional integration of oral implants following sinus augmentation with autologous bone grafts and conventionally placed endosseous implants in the local bone was similar. The additional implant stabilization within the mandibular cortical bone grafts resulted in very low Periotest scores. In periodontally compromised subjects treated for chronic adult periodontitis with minimal maxillary bone height less than 5 mm the endosseous implantation with simultaneous sinus augmentation is recommended as an appropriate technique for long-term oral implant rehabilitation.     

The influence of mandibular dentition on implant failures in bone-grafted edentulous maxillae

PURPOSE: To evaluate the influence of mandibular dentition on the performance of maxillary implants prior to definitive prosthesis attachment in maxillae that have been reconstructed with autogenous bone grafts. MATERIALS AND METHODS: A retrospective review of 90 consecutive patients, 31 men and 59 women, with a mean age of 57.4 years, was conducted. All patients underwent treatment planning to receive endosseous implants in the edentulous maxilla in conjunction with autogenous bone grafting. During the time from implant and/or bone graft placement until placement of the definitive restorations in the maxillae, the mandibular dentitions were recorded and categorized into 6 groups based upon the presence and distribution of teeth. RESULTS: Of 643 implants placed, 118 (18.4%) were lost between implant placement and definitive prosthesis placement. The type of mandibular dentition was significantly associated with implant failure during this time interval (P < .001). In particular, the patients with implants opposing unilateral occlusal support showed the highest rate of implant failure (43.8%, or 28 of 64 implants). Implants that opposed a mandibular implant-supported fixed prosthesis demonstrated an implant failure rate of 14.3% (10 of 70), and in patients with a removable mandibular denture, the implant failure rate was 6.2% (4 of 65 implants failed). The overall mean patient follow-up was 64.2 months. At 60 months, the cumulative implant failure rate based on the Kaplan-Meier method was 20.2%. DISCUSSION: Unfavorable concentration of forces on the maxilla may contribute to increased risk of implant failure. CONCLUSION: Effort should be made to create a favorable occlusion in the mandible, with attention being paid to broad distribution of occlusal contacts.     

下颌骨取骨onlay植骨改善种植骨量不足的临床研究

目的:评价应用下颌骨取骨onlay植骨改善种植术前重度萎缩牙槽嵴的手术方法及疗效。方法:18例患者接受了下颌骨来源的onlay植骨术,手术同期或术后4～6个月共植入22颗种植体,并于术后4～6个月暴露种植体,最终完成烤瓷冠修复。结果:植骨术后无并发症发生,2例骨吸收较明显,其余均顺利植入种植体,二期手术时骨吸收平均20%。所有病例均最终完成种植修复,观察6～28个月,无种植体脱落。结论:下颌骨取骨onlay植骨修复重度萎缩的牙槽嵴操作简便,效果可靠。     

The use of autogenous block graft for augmentation of the atrophic alveolar ridge

The use of osseointegrated implants has become a standard treatment option in modern dental rehabilitation. Adequate bone quantity and quality is a prerequisite for good esthetic and biomechanical result. Alveolar ridge defects can be the result of trauma, periodontal diseases or other pathologic conditions. In these cases, alveolar ridge augmentation is needed if endosseous implants are to be used. While xenografts, alloplastic bone grafts and allografts have been proposed for alveolar ridge augmentation, the use of autogenous bone grafts represents the "gold standard" for bone augmentation procedures. Either intraoral or extraoral sites may be considered for donor sites. Although the iliac crest is the most common donor site in maxillofacial reconstruction, the mandibular symphysis or ramus offer important advantages like avoidance of general anesthesia, convenience due to the proximity between the donor site and the augmentation site and avoidance of cutaneous scar. Bone harvested from intraoral donor site is less associated with resorption when compared with iliac bone because membranous grafts revascularize more quickly than endocondral bone grafts. The main disadvantage of the intraoral donor sites is the limited amount of available bone. Alveolar ridge augmentation using autologous bone block, can be done during implant placement or staged with implant placement, after bone graft healing. In the staged technique, a better implant positioning and the use of wide diameter implants are possible. The overall implant success is higher in the staged technique. Alveolar ridge augmentation using autogenous block graft is a predictable way of treatment, for the atrophic alveolar ridge before implant placement.     

The use of a trephine biopsy needle to obtain autogenous corticocancellous bone from the iliac crest: technical note

In the absence of adequate bone height, augmentation of the maxillary antrum prior to placement of endosseous implants is a well-established procedure. Although there is a debate among clinicians as to which grafting materials are the most advantageous, autogenous bone is still considered by many to be the gold standard. Often patients require more graft material than is generally available from intraoral sites. This has led clinicians to utilize allografts, xenografts, or a combination of autologous and synthetic bone. Extraoral sites can provide a greater volume of autogenous bone than intraoral sites. However, harvesting extraoral donor bone is frequently associated with adverse consequences in excess of the primary objective (i.e., the placement of endosseous implants in the posterior maxilla with minimal morbidity). A method for obtaining a significant volume of corticocancellous autogenous bone for augmentation of the maxillary antrum is described. The technique is efficacious and cost effective and results in minimal morbidity.     

Implant stability measurement of delayed and immediately loaded implants during healing

The purpose of the present study was (1) to measure the primary stability of ITI implants placed in both jaws and determine the factors that affect the implant stability quotient (ISQ) determined by the resonance frequency method and (2) to monitor implant stability during the first 3 months of healing and evaluate any difference between immediately loaded (IL) implants and standard delayed loaded (DL) implants. The IL and DL groups consisted of 18 patients/63 implants and 18 patients/43 implants. IL implants were loaded after 2 days; DL implants were left to heal according to the one-stage procedure. The ISQ was recorded with an Osstell apparatus (Integration Diagnostics AB, Gothenburg, Sweden) at implant placement, after 1, 2, 4, 6, 8, 10 and 12 weeks. Primary stability was affected by the jaw and the bone type. The ISQ was higher in the mandible (59.8+/-6.7) than the maxilla (55.0+/-6.8). The ISQ was significantly higher in type I bone (62.8+/-7.2) than in type III bone (56.0+/-7.8). The implant position, implant length, implant diameter and implant deepening (esthetic plus implants) did not affect primary stability. After 3 months, the gain in stability was higher in the mandible than in the maxilla. The influence of bone type was leveled off and bone quality did not affect implant stability. The resonance-frequency analysis method did not reveal any difference in implant stability between the IL and DL implants over the healing period. Implant stability remained constant or increased slightly during the first 4-6 weeks and then increased more markedly. One DL and IL implant failed; both were 8 mm long placed in type III bone. At the 1-year control, the survival rate of the IL and the DL implants was 98.4% and 97.7%, respectively. This study showed no difference in implant stability between the IL and DL procedures over the first 3 months. IL short-span bridges placed in the posterior region and full arch rehabilitation of the maxilla with ITI sandblasted-and-etched implants were highly predictable.     

Clinical,histological and histomorphometrical study of maxillary sinus augmentation using cortico-cancellous fresh frozen bone chips

BackgroundInsufficient bone volume in the posterior maxilla can be a major problem when placing dental implants. One of the goals of sinus augmentation procedures is the creation of sufficient volume of vital bone for the subsequent insertion and complete osseointegration of implants placed in the posterior maxilla.The aim of the present study was a clinical, histological and histomorphometrical analysis of maxillary sinus augmentation using human fresh frozen bone (FFB) allografts for maxillary sinus lift augmentation procedures.MethodsFifteen patients were treated with maxillary sinus augmentation using FFB. After three months, a bone biopsy was taken before implant placement in order to evaluate the healed bone from a histological and histomorphometrical point of view. After further three months, all implants were osseointegrated according to radiographic and clinical examinations. Abutment connection was performed and the patients received prosthetic restoration of the missing teeth.ResultsHistologically all the specimens showed signs of active remodelling and all the tissues were free of inflammatory cells. After 12 months of assessment, no implants had failed.ConclusionOur findings suggest that FFB is a biocompatible material that can be successfully used for maxillary sinus augmentation.     

Reconstruction of the severely resorbed mandible prior to vestibuloplasty or placement of endosseous implants. A 2 to 5 year follow-up.

Ninety-two patients underwent augmentation of the severely resorbed mandible using corticocancellous bone grafts in the symphysis and a mixture of autogenous cancellous bone chips and hydroxylapatite particles in the posterior area. This study, extending from 2 to 5 years, shows that predictable and stable results were achieved. The average loss of height measured at 3 reference points was approximately 20%. Slight sensory disturbance was present in 19 patients (23%). Benefits derived from augmentation of the atrophic mandible include: improvement of facial form due to the renewed support of the collapsed circumoral muscles, a decrease in the intermaxillary distance, and restoration of mandibular bone bulk that will accommodate endosseous implants of maximum size.     

Maxillary autogenous bone grafting

Reconstruction of the atrophic maxilla for dental implant placement has many unique considerations. There are several methods available to augment the atrophic maxilla. Of these, autogenous bone grafting offers a well-proven predictable method for ridge augmentation and defect repair for dental implant placement. There are several advantages of using autogenous bone grafts. This article primarily focuses on the use of autogenous onlay bone grafts to reconstruct the atrophic maxilla.     

Cortical tenting grafting technique in the severely atrophic alveolar ridge for implant site preparation

OBJECTIVES: Alveolar ridge augmentation using intraoral autogenous block grafts to augment localized alveolar ridge defects before implant placement is a predictable method. However, large severely atrophic edentulous segments may require extraoral donor sites. The purpose of this study was to evaluate the effectiveness of using intraoral cortical block grafts in combination with particulate human mineralized allograft, in a "tenting" fashion, to augment large atrophic alveolar ridge defects for implant placement. MATERIALS: This prospective case study evaluated augmentation in 10 consecutive patients with severely resorbed alveolar ridges missing a minimum of 4 adjacent teeth. Before augmentation, all grafted sites were deemed inadequate for placement of a standard 4-mm-diameter implant. Horizontal ridge augmentation was performed using autologous membranous cortical bone grafts from an oral donor site to tent out the soft tissue matrix and periosteum for the adjacent particulate allograft. The ridges were clinically evaluated 4 to 5 months after augmentation, and 42 implants were placed at that time. RESULTS: Implants were successfully placed at all grafted sites 4 to 5 months after the original graft date. Clinical evaluation of the grafted sites upon re-entry revealed uniform ridge anatomy. All edentulous segments had at least 2 implants placed of at least 4.0 mm diameter. In all, 42 implants were placed into grafted sites in the 10 patients. Implants were checked for osseointegration by using a counter torque of 35 N.cm. One implant failed to integrate. Mean follow-up was 22 months after implant placement. All augmented ridges had retained their functional and esthetic integrity at 1 year after original augmentation. CONCLUSION: Tenting of the periosteum and soft tissue matrix using a cortical bone block maintains space and minimizes resorption of the particulate allograft volume. In addition, bridging the cortical blocks with particulate bone avoids unaesthetic ridge defects between cortical block grafts in larger ridge defects. The result was a more uniform and esthetic alveolar ridge, capable of maintaining an implant-supported prosthesis. The technique offers predictable functional and esthetic reconstruction of large-volume defects without extensive amounts of autogenous bone. This offers a superior functional and esthetic result than with either cortical or particulate grafting alone.     

Full mouth implant rehabilitation of a patient with ectodermal dysplasia after orthognathic surgery, sinus and ridge augmentation: a clinical report

An 18-year-old male presented severe hypodontia due to hypohidrotic ectodermal dysplasia was treated with Le Fort I maxillary osteotomy with simultaneous sinus floor augmentation using the mixture of cortical autogenous bone graft harvested from iliac crest and organic Bio-Oss to position the maxilla in a right occlusal plane with respect to the mandible, and to construct adequate bone volume at posterior maxilla allowing proper implant placement. Due to the poor bone quality at other sites, ridge augmentation with onlay graft was done to construct adequate bone volume allowing proper implant placement, using tissue harvested from the iliac bone. Seven implants were placed in the maxilla and 7 implants were inserted in the mandible and screw-retained metal ceramic FPDs were fabricated. The two year follow up data showed that dental implants should be considered as a good treatment modality for patients with ectodermal dysplasia.     

Maxillary autogenous bone grafting

Reconstruction of the atrophic maxilla for dental implant placement has many unique considerations. There are several methods available to augment the atrophic maxilla. Of these, autogenous bone grafting offers a well-proven predictable method for ridge augmentation and defect repair for dental implant placement. There are several advantages of using autogenous bone grafts. This article primarily focuses on the use of autogenous onlay bone grafts to reconstruct the atrophic maxilla.