Histologic and radiographic evidence of vertical ridge augmentation utilizing distraction osteogenesis: 10 consecutively placed distractors

BACKGROUND: Vertical ridge augmentation for dental implant placement is one of the greatest challenges facing the surgeon. Inadequate vertical bone compromises the implant positioning and resulting restoration. The cleansibility, esthetics, and mechanical properties of the restoration can all be compromised. While the technique of distraction osteogenesis has been successfully employed for long bone applications for over 40 years, it has only recently been introduced as a technique for vertical ridge augmentation prior to dental implant reconstruction. METHODS: In this study, the placement of 10 consecutive distractors in 7 patients was evaluated. The surgical technique, latency period, distraction rate, and consolidation period are reviewed. RESULTS: The technique of distraction osteogenesis resulted in an average vertical augmentation of 7 mm, with a range of 5 to 9 mm. There were no complications affecting the outcome of the distraction procedure. No failures have occurred to date in the 16 implants that were placed and loaded following distraction. CONCLUSIONS: In summary, clinical, histologic, and radiographic evidence of consistent vertical bone augmentation was found with this technique of distraction osteogenesis for vertical ridge augmentation.     

Distraction osteogenesis versus autogenous onlay grafting. Part I: outcome of implant integration

PURPOSE: The primary goal of this study was to compare bone-to-implant contact (BIC) in alveolar bone augmented by distraction osteogenesis with BIC in alveolar bone augmented by onlay iliac crest grafting. MATERIALS AND METHODS: Alveolar bone defects were created bilaterally in 5 American foxhounds, and after healing, bone augmentation was accomplished using distraction osteogenesis on 1 side of the jaw and onlay grafting on the other. Twelve weeks after consolidation, implants were placed in augmented and control sites. The animals were sacrificed and the jaws harvested for histologic analysis after an additional 8 weeks. RESULTS: The mean BIC was 54.7% +/- 14.6% for implants placed in distracted sites, 53.8% +/- 11.8% for sites where an onlay graft was used, and 51.2% +/- 14.4% for control sites. Significant differences in BIC were noted between experimental and control sites only at the apical third of the implant (19.8 +/- 1.8 for distracted sites; 15.5 +/- 1.5 for grafted sites; 8.0 +/- 0.5 for control sites; P < .05). DISCUSSION: The data showed that both distraction osteogenesis and onlay grafting produce sufficient bone for implant placement. There were no differences between procedures in regard to BIC after 8 weeks. CONCLUSION: These data suggest that both onlay grafting and vertical distraction are appropriate methods for bone augmentation prior to implant placement.     

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.     

Use of alveolar distraction osteogenesis for implant placement: a case report with eight‐year follow‐up

Insufficient alveolar ridge width may impede the success of dental implants. Techniques for resolving this problem include autologous bone grafts, guided bone regeneration, bone splitting and bone spreading techniques. Recently, alveolar distraction osteogenesis has become an alternative method for alveolar augmentation. We propose the use of alveolar bone distraction for insufficient alveolar ridge width. A healthy 33‐year‐old female presented with missing teeth to our clinic. Clinical and radiographic examination revealed the alveolar ridge was too narrow for placement of dental implants. Therefore, horizontal distraction osteogenesis of the posterior mandibular ridge was chosen for augmentation. Two months later, two implants were placed. No significant marginal bone resorption was seen around the implants eight years after placement. Our results indicate that horizontal alveolar distraction is recommended to increase ridge width and allow placement of standard dental implants.     

The outcome of intraoral onlay block bone grafts on alveolar ridge augmentations: A systematic review

Aim: The purpose of this study was to systematically review clinical studies examining the survival and success rates of implants placed with intraoral onlay autogenous bone grafts to answer the following question: do ridge augmentations procedures with intraoral onlay block bone grafts in conjunction with or prior to implant placement influence implant outcome when compared with a control group (guided bone regeneration, alveolar distraction, native bone or short dental implants.)? Material and Method: An electronic data banks and hand searching were used to find relevant articles on vertical and lateral augmentation procedures performed with intraoral onlay block bone grafts for dental implant therapy published up to October 2013. Publications in English, on human subjects, with a controlled study design –involving at least one group with defects treated with intraoral onlay block bone grafts, more than five patients and a minimum follow-up of 12 months after prosthetic loading were included. Two reviewers extracted the data. Results: A total of 6 studies met the inclusion criteria: 4 studies on horizontal augmentation and 2 studies on vertical augmentation. Intraoperative complications were not reported. Most common postsurgical complications included mainly mucosal dehiscences (4 studies), bone graft or membrane exposures (3 studies), complete failures of block grafts (2 studies) and neurosensory alterations (4 studies). For lateral augmentation procedures, implant survival rates ranged from 96.9% to 100%, while for vertical augmentation they ranged from 89.5% to 100%. None article studied the soft tissues healing. Conclusions: Survival and success rates of implants placed in horizontally and vertically resorbed edentulous ridges reconstructed with block bone grafts are similar to those of implants placed in native bone, in distracted sites or with guided bone regeneration. More surgical challenges and morbidity arise from vertical augmentations, thus short implants may be a feasible option. Key words:Alveolar ridge augmentation, intraoral bone grafts, onlay grafts, block grafts, dental implants.     

Vertical bone augmentation: where are we now?

As the prevalence of implants has increased, so has the challenge to augment the remaining osseous structure to house those implants. The biggest surgical challenge clinically is to augment lost bone vertically. The purpose of this article is to review currently available techniques for achieving greater vertical dimension before implant placement. A literature search was conducted using MEDLINE to find all articles published between 1970 and 2004 regarding vertical bone augmentation. Following the literature search, all articles were reviewed and summarized in this review article of vertical bone augmentation. The results of the research showed that guided-bone regeneration, monocortical onlay grafting, and distraction osteogenesis have the potential to be applied to augment deficient areas vertically. The expectations of dimensional gain and bone quality are unique to each technique, as well as the potential complications. Distraction osteogenesis has had the greatest potential for vertical gain, while guided-bone regeneration and monocortical onlay grafting achieve similar results. The choice of procedure is to be based upon the patient's existing anatomy, degree of vertical deficiency, and willingness to participate in treatment.     

Inlay versus Onlay Iliac Bone Grafting in Atrophic Posterior Mandible: A Prospective Controlled Clinical Trial for the Comparison of Two Techniques

Purpose: To compare the efficacy of inlay and onlay bone grafting techniques in terms of vertical bone formation and implant outcomes for correcting atrophic posterior mandibles.
Materials and Methods: Twenty surgical sites were assigned to two treatment groups, inlay and onlay, with iliac crest as donor site. After 3 to 4 months, 43 implants were placed and loaded 4 months later. The median follow up after loading was 18 months.
Results: For the inlay versus onlay group, median bone gain was 4.9 versus 6.5 mm ( p  = .019), median bone resorption was 0.5 versus 2.75 mm ( p  < .001), and median final vertical augmentation was 4.1 versus 4 mm ( p  = .190). The implant survival rate was 100% in both groups, while the implant success rate was 90% versus 86.9% ( p  = .190, not significant). A minor and major complication rate of 20% and 10%, respectively, for both groups was encountered.
Conclusions: Inlay results in less bone resorption and more predictable outcomes, but requires an experienced surgeon. In contrast, onlay results in greater bone resorption and requires a bone block graft oversized in height, but involves a shorter learning curve. Once implant placement has been carried out, the outcomes are similar for both procedures.     

骨增量技术在口腔种植中的应用进展

种植术区的骨质、骨量是种植手术成败的关键因素之一,临床上常常因为患者缺牙区骨量不足而使得种植医生及患者对种植牙望而却步,随着骨增量技术的发展,使得种植手术的适应证不断扩大,常见的骨增量技术包括骨劈开术、骨挤压术、引导骨再生技术、牵张成骨术、上颌窦提升术及骨移植术等,这些技术的单独及联合应用均不同程度地增加了种植手术的成功率,本文就骨增量技术在牙种植的应用进展作一综述。     

Long-term follow-up implant site development in the submerged mandibular primary second molars: a case report

Treatment of ankylosed and submerged primary molars without permanent successors is challenging, as normal vertical dentoalveolar growth is compromised. Thus, grafting techniques and distraction osteogenesis are performed for ridge augmentation before implant restoration. However, these techniques are invasive with limited success. Another treatment for implant site development is noninvasive forced eruption. This case report describes long-term follow-up of alveolar ridge augmentation in the submerged mandibular primary second molars using subluxation and orthodontic forced eruption for implant site development. A 19-year old female had Class II molar relationships, upper anterior crowding with large overjet, missing four second premolars and submerged mandibular primary second molars with inadequate vertical development of alveolar bone. For the vertical alveolar bone alterations in the mandible, forced eruption with subluxation of ankylosed lower primary second molars was applied. Treatment outcome was evaluated over 5 years with stable occlusion, healthy periodontal tissues, and successful radiographic results.     

Current perspectives on the role of ridge (socket) preservation procedures in dental implant treatment in the aesthetic zone

Augmentation of the extraction socket (ridge preservation) is increasingly being advocated in anticipation of implant placement. The aim of this article is to review the available evidence with regards to ridge preservation procedures, investigating whether these techniques improve dental implant treatment outcomes. Evidence is examined to compare these techniques to other treatment alternatives such as implant placement with simultaneous lateral augmentation. An electronic PubMed search was conducted using search terms relevant to assessing treatment outcomes in association with ridge preservation. Titles were screened and full text obtained where relevant. Further full text articles were obtained from analysis of those papers yielded from the original search. Twenty‐two papers were finally selected for analysis. Ridge preservation techniques are effective in minimizing post‐extraction alveolar ridge contraction. However, there is insufficient evidence to suggest that the use of these techniques in conjunction with dental implant treatment improves implant treatment outcomes. Furthermore, ridge preservation does not necessarily eliminate the need for further simultaneous augmentation at the time of implant placement. The delayed healing associated with ridge preservation using socket grafting necessitates a commitment to a delayed placement protocol. The extended treatment time, compromised healing and expense related to ridge preservation suggests a more cautious approach with regards to the indication of such techniques.     

Augmentation in two stages of atrophic alveolar bone prior to dental rehabilitation: a case report

AIM: The aim of this report is to describe a significantly deficient case of alveolar bone that was managed by alveolar bone augmentation using a technique of distraction osteogensis and onlay bone grafting prior to dental implant placement. BACKGROUND: Injury to the teeth and alveolar ridge of the maxillary anterior region can cause a severe alveolar ridge deficiency resulting in ridge atrophy and maxillary retrognathism. The loss of these teeth and alveolar bone together with fibrotic scar formation can result in adverse changes of the interarch space, occlusal plane, arch relationship, and arch form which complicates rehabilitation and can compromise the esthetic outcome. While implant dentistry has become a new paradigm in oral reconstruction and replacement of missing teeth, ideal implant positioning can be compromised by inadequate alveolar bone in terms of bone height, width, and quality of the bone itself. Correction of osseous deficiencies with ridge augmentation allows ideal implant placement and creates a more natural soft tissue profile which influences crown anatomy and esthetics. REPORT: A 20-year-old female presented with a complaint of poor esthetics resulting from oral injuries incurred in a traffic accident six years previously. In addition to a mandibular parasymphyseal fracture, five maxillary anterior teeth and the most of the alveolar ridge were lost. Clinical examination revealed severe loss of bone in the maxillary anterior region, an absence of a labial sulcus, loss of upper lip support, and a slight over eruption of the mandibular anterior teeth. In preparation for dental implants a distraction osteogenesis surgical procedure was done to lengthen the height of the alveolar ridge. After a three-month healing period, the width of the residual ridge was found to be insufficient for implant placement. To correct this deficiency, a bone graft of a cortiocancellous block was harvested from the chin and fixed to the labial aspect of the ridge. To facilitate revascularization, small perforations were made in the cortical bone of the alveolar ridge at the recipient site before cancellous bone retrieved from the donor site was gently placed between the bone block and the ridge. The patient was then appropriately medicated and healing was uneventful. After three months, the width of the residual ridge was assessed to be adequate for endosseous implants. SUMMARY: The clinical result reported here has shown several procedures may be necessary for the rehabilitation of a trauma patient. Distraction osteogenesis per se may not always satisfactorily improve the anatomical alveolar anatomy but it has advantages over other methods of augmentation. It can improve the height and also expand the soft tissue for further bone grafting. Augmentation of the alveolar bone with an onlay bone graft often provides the desired gain of bone, allows for the ideal placement of dental implants, and improves any discrepancy between the upper and lower arches.     

For which clinical indications in dental implantology is the use of bone substitute materials scientifically substantiated?

Purpose: The objective of this systematic review was to provide a basis for an expert consensus group to evaluate the influence of different particulate bone substitute materials in local bone augmentation procedures in conjunction with dental implant placement on implant survival and histology. Materials and methods: The following indications were analysed with either simultaneous or delayed dental implant placement: external or internal maxillary sinus floor elevation and vertical and/or lateral alveolar ridge augmentation. Retro- and prospective studies written in English or German including 20 or more patients (for randomised, controlled trials and prospective, split-mouth trials with 5 or more patients) were eligible for this review. The review focused on (1) performance of the augmentation procedures (total augmentation loss, gain of vertical and horizontal alveolar ridge dimensions, histomorphometric data of the augmented areas) and (2) dental implant success criteria (survival rates of the inserted dental implants, peri-implant bone levels under functional loading). Results: From over 3800 abstracts identified, 72 full-text articles fulfilled the inclusion criteria and were further evaluated (52 studies on maxillary sinus floor elevation procedures and 21 studies on vertical and/or lateral alveolar ridge augmentation). The majority of the included studies were prospective studies including a rather limited number of patients and short observation periods. Conclusions: There is a high level of evidence that survival rates of dental implants placed into augmented areas are comparable with survival rates of implants placed into pristine bone. For maxillary sinus floor elevation, all investigated bone substitute materials performed equally well compared with bone, with high dental implant survival rates and adequate histomorphometric data. For the alveolar ridge augmentation procedures, the heterogeneity of the available data did not allow identification of a superior grafting technique.     

Distraction osteogensis: a surgical option for restoring missing tissue in the anterior esthetic zone

Common causes of alveolar defects include bone resorption due to loss of teeth, infection, or trauma. There is often insufficient height or width of residual bone, and ridge augmentation may be required prior to implant placement. These defects range from small alveolar deficiencies to more complex, extensive bony defects. Various techniques are available for reconstructing alveolar ridges. Without augmentation, dental implants may have to be placed in anatomically unfavorable positions or have adverse angulations. These position/angulation compromises can lead to esthetic dissatisfaction, mechanical overload, and possibly implant loss. Both bone grafting and distraction osteogenesis are predictable methods for restoring missing tissue.     

Bone augmentation techniques

BACKGROUND: The advent of osseointegration and advances in biomaterials and techniques have contributed to increased application of dental implants in the restoration of partial and completely edentulous patients. Often, in these patients, soft and hard tissue defects result from a variety of causes, such as infection, trauma, and tooth loss. These create an anatomically less favorable foundation for ideal implant placement. For prosthetic-driven dental implant therapy, reconstruction of the alveolar bone through a variety of regenerative surgical procedures has become predictable; it may be necessary prior to implant placement or simultaneously at the time of implant surgery to provide a restoration with a good long-term prognosis. Regenerative procedures are used for socket preservation, sinus augmentation, and horizontal and vertical ridge augmentation. METHODS: A broad overview of the published findings in the English literature related to various bone augmentation techniques is outlined. A comprehensive computer-based search was performed using various databases that include Medline and PubMed. A total of 267 papers were considered, with non-peer-reviewed articles eliminated as much as possible. RESULTS: The techniques for reconstruction of bony defects that are reviewed in this paper include the use of particulate bone grafts and bone graft substitutes, barrier membranes for guided bone regeneration, autogenous and allogenic block grafts, and the application of distraction osteogenesis. CONCLUSIONS: Many different techniques exist for effective bone augmentation. The approach is largely dependent on the extent of the defect and specific procedures to be performed for the implant reconstruction. It is most appropriate to use an evidenced-based approach when a treatment plan is being developed for bone augmentation cases.     

Alveolar distraction: a possible new alternative to bone grafting

Distraction osteogenesis is a new concept to periodontics that may replace the more traditional bone grafting techniques of onlay grafts and titanium membrane procedures. Distraction osteogenesis is not fraught with the complications of graft and membrane exposure or inadequate tissue coverage, which makes the distraction procedure an ideal technique to grow unlimited amounts of vertical bone height. This article describes a technique to grow new bone and soft tissue in a maxillary alveolar defect using a new technique called alveolar distraction osteogenesis. A case report is presented of the distraction procedure, reentry 6 months later, implant placement, and restoration.     

Maxillary alveolar ridge reconstruction with nonvascularized autogenous block bone: clinical results.

PURPOSE: The purposes of this study were to evaluate the clinical success of bone reconstruction of the severely atrophic maxilla using autogenous bone harvested from the anterosuperior edge of iliac wing and to analyze the clinical success and the marginal bone level of dental implants placed 4 to 5 months after bone grafting and before prosthetic rehabilitation. PATIENTS AND METHODS: Fifty-six patients (18 men, 38 women) aged 27 to 63 years were included in the study and required treatment for maxillary atrophy. All patients selected were scheduled for onlay bone graft and titanium implants in a 2-stage procedure. The dental implants were inserted 4 to 5 months after grafting. RESULTS: No major complications were observed from the donor sites. A total of 129 onlay bone grafts were used to augment 56 severely resorbed maxillas. Three out of 129 bone grafts had to be removed because of early exposure occurring with bone grafts placed to increase the vertical dimension of the alveolar ridge. One hundred sixty-two implants were placed in the area of bone augmentation. Seven implants failed to integrate and were successfully re-placed without any need for additional bone grafting. The clinical measurements for bone resorption around implants revealed a mean bone loss of 0.05 mm (+/- 0.2); the marginal bone level evaluated with periapical radiographies was 0.3 mm (+/- 0.4) at implant placement and 0.1 mm (+/- 0.3) 6 months after placement. CONCLUSION: The success rate of the block grafts was very good. The clinical and radiographic bone observations showed a very low rate of resorption after bone graft and implant placement. Therefore, on the basis of this preliminary study, iliac bone grafts (from the anterosuperior edge of the iliac wing) can be considered a promising treatment for severe maxillary atrophy.     

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。     

牵张成骨和引导骨再生术在垂直骨增量上的比较研究

随着种植外科的进展,大量垂直向和水平向骨增量技术得到了发展。许多种植患者存在垂直向骨量不足的问题,需要增加垂直向骨量;但垂直向骨增量相对于水平向骨增量难度比较大,预见性较差,往往易致较多的并发症;因此,垂直向骨增量技术受到了越来越多的关注。引导骨再生技术和牵张成骨术是2类较常用的垂直向骨增量技术,在临床上已得到一定的应用,本文对其在垂直向骨增量上的研究进展作一综述。     

Alveolar distraction osteogenesis vs. vertical guided bone regeneration for the correction of vertically deficient edentulous ridges: a 1-3-year prospective study on humans

The purpose of this prospective study was to compare vertical guided bone regeneration (GBR) and vertical distraction osteogenesis (DO) for their ability in correcting vertically deficient alveolar ridges and their ability in maintaining over time the vertical bone gain obtained before and after implant placement. Eleven patients (group 1) were treated by means of vertical GBR with autogenous bone and e-PTFE membranes, while 10 patients (group 2) were treated by means of DO. In group 1, six patients received implants at the time of GBR (subgroup 1A), while five patients had implants placed at the time of membrane removal (subgroup 1B). In group 2, implants were placed at the time of distraction device removal. A total of 25 implants were placed in group 1 and 34 implants were placed in group 2 patients. Three to 5 months after implant placement, patients were rehabilitated with implant-borne dental prostheses. The following parameters were evaluated: (a) bone resorption of the regenerated ridges before and after implant placement; (b) peri-implant clinical parameters 1, 2, and 3 years after prosthetic loading of implants; (c) survival and success rates of implants. Bone resorption values before and after implant placement were significantly higher in group 1. The results suggested that both techniques may improve the deficit of vertically resorbed edentulous ridges, although distraction osteogenesis seems to be more predictable as far as the long-term prognosis of vertical bone gain is concerned. Implant survival rates as well as peri-implant clinical parameters do not differ significantly between the two groups, whereas the success rate of implants placed in group 2 patients was higher than that obtained in group 1 patients.     

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.