Autogenous bone ring augmentation around single tooth implantation in the esthetic zone: A retrospective case series study with 2-3 years of follow-up

Evaluating the Effects of Dynamic Navigation on the Accuracy and Outcomes of the Autogenous Bone Ring Technique for Vertical Ridge Augmentation: A Pilot Randomized Controlled Trial

OBJECTIVES

Autogenous bone ring technique (BRT) is a one-stage vertical augmentation approach with simultaneous implant placement. The aim of this study was to compare the accuracy and efficacy of autogenous BRT assisted by dynamic navigation (DN) with freehand approach (FA) for vertical ridge augmentation.

MATERIALS AND METHODS

Twenty-four patients eligible for autogenous BRT were randomly assigned to DN or FA groups. Digital preoperative design was conducted for both groups. BRT surgeries were executed with or without the aid of DN in the two groups. Accuracy outcomes evaluated angular and linear deviations at the bone ring in the donor site (BR-D), recipient site (BR-R), and implant entry/apex between planned and actual positions revealed by cone-beam computed tomography. Vertical augmentation-related outcomes, surgical complications, and patient-reported outcomes were assessed over 6 months.

RESULTS

Twenty-four patients underwent surgery while one was lost to follow-up. The DN group showed significantly lower mean (SD) BR-R angular (3.58 [2.07] vs. 8.77 [4.20]°) and entry deviation (1.43 [0.51] vs. 2.01 [0.70] mm). For BR-D, the DN group had significantly lower angular (4.80 [2.62] vs. 12.97 [6.26]°), entry (1.45 [0.96] vs. 3.52 [1.54] mm), and apex deviation (1.28 [0.64] vs. 3.50 [1.47] mm) compared to the FA group. Implant angular deviation (3.74 [2.14] vs. 9.17 [4.39]°) and apex deviation (1.75 [0.44] vs. 2.35 [0.82] mm) was significantly lower in the DN group. In the FA group, one patient exhibited temporary lower lip hypoesthesia. No significant differences were observed in vertical bone gain, resorption, or patient-reported outcomes.

CONCLUSIONS

Compared to FA, DN may improve the accuracy of autogenous BRT procedures for vertical ridge augmentation while minimizing invasiveness.

TRAIL REGISTRATION

This study was registered at the Chinese Clinical Trial Registry (https://www.chictr.org.cn; Registration No. ChiCTR2200065585; registration date: 2022/11/09).

Dynamic navigation-assisted bone ring technique for partially edentulous patients with severe vertical ridge defects

The autogenous bone ring technique is among the approaches for vertical alveolar ridge augmentation, and this technique can enable simultaneous implantation. However, the outcomes can be compromised due to donor site morbidity, shifting of the bone ring graft positioning, and inaccurate implant placement. In recent decades, dynamic navigation systems have been introduced into the field of implantology, allowing the accuracy of outcomes to be improved. This Technical Note describes the use of dynamic navigation to guide bone ring surgery, which is expected to enable more precise and predictable bone augmentation and implantation procedures, reduce the risk of injuries to the adjacent anatomical structures, and achieve better treatment outcomes.

Efficacy of bone ring grafts for the reconstruction of alveolar ridge deficiencies: a systematic review. Part II: animal trials

Background

Bone ring (BR) grafts have been introduced to reconstruct alveolar ridge defects with simultaneous implant placement, but their clinical effectiveness remains undetermined. The aim of the current systematic review was to critically appraise evidence from animal studies regarding the effectiveness of BR grafts in alveolar ridge reconstruction and their variations under different surgical protocols.

Methods

Electronic retrieval of six databases (MEDLINE, Embase, Cochrane Library, ScienceDirect, Web of Science, and Scopus) and citation search until 11 October 2023, for animal studies on bone augmentation employing BR grafts. The outcome variables were total bone area (BA), bone volume (BV), bone-implant contact (BIC), and histology. The protocol was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and prospectively registered with PROSPERO (CRD42023453949).

Results

Ten studies were included in the qualitative analysis according to the screening criteria. Two studies demonstrated favorable bone remodeling and osseointegration of the BR with both the implant and pristine bone. A comparative study between autogenous BRs and allogenic BRs reported a higher percentage of BA and BIC at 4 months of healing, but conflicting data were observed at 8 months. Another study indicated a significant advantage of autogenous BRs over bovine and biphasic ceramic BRs in terms of BA and BIC after 5 weeks. Three studies found that using collagen membranes did not significantly affect BA, BV, or BIC when used simultaneously with autogenous BRs during implant placement. Two studies evaluated one-stage and two-stage implant placement in conjunction with BR grafts, revealing similar levels of BA, BV, and BIC except for differences in total treatment time. Furthermore, one study found that the use of mucogingival junction incision and split-thickness flap significantly reduced the incidence of wound dehiscence compared with conventional incision and flap.

Conclusions

Vertical bone augmentation surgery utilizing BR grafts with one-stage implant placement yielded histological and histomorphometric outcomes comparable to those achieved with two-stage implant placement or the additional application of collagen membrane.

Efficacy of bone ring grafts for the reconstruction of alveolar ridge deficiencies: A systematic review. Part I: Clinical trials

BACKGROUND

Bone ring (BR) grafts have been introduced to reconstruct alveolar ridge defects with simultaneous implant placement, but its clinical effectiveness remains undetermined. This systematic review aimed to comprehensively investigate BR grafts in diverse scenarios of ridge defect with simultaneous or staged implant placement.

METHODS

Electronic retrieval of MEDLINE, Embase, Cochrane Library(CENTRAL), Web of Science, Scopus, and citation search until August 3, 2023, was used to identify relevant clinical articles that utilized BR grafts for ridge defect reconstruction. The quality of evidence in the studies reviewed was assessed with the Joanna Briggs Institute Critical Appraisal tool. The protocol was registered in Prospective Register of Systematic Reviews (CRD42023453943).

RESULTS

Fourteen studies with 251 BRs were identified, of which 8 studies were for alveolar ridge augmentation, 4 studies were for extraction socket augmentation, and 2 studies were for sinus floor elevation. Reported sources of BRs included autografts, allografts, and xenografts. The follow-up period ranged from 4 months to 4.7 years. Regarding the primary outcomes, the utilization of BR grafts demonstrated favorable bone gain along with acceptable graft absorption and marginal bone loss. Regarding the secondary outcomes, satisfactory bone mineral density and implant stability were confirmed, accompanied by a recorded incidence of postoperative complications (20 cases) and an implant failure rate of 5.58%.

CONCLUSIONS

BR grafting with simultaneous or staged implant insertion is an effective approach for reconstructing alveolar ridge deficiencies. The BR grafts demonstrate favorable bone remodeling and osteointegration with the alveolar bone and implant; however, its success may be compromised by complications. Future studies should further investigate the clinical efficacy of BR grafting comparing to other bone augmentation techniques in diverse scenarios.