Treatment Outcome of Using Guided Bone Regeneration for Bone Augmentation for the Placement of Dental Implants – A Systematic Review

ABSTRACT

Aim:

The objective of this review is to evaluate the treatment outcome differences between guided bone regeneration (GBR) and other techniques of bone augmentation for the placement of dental implants.

Materials and Methods:

This review was performed by two reviewers electronically on the PubMed and Cochrane database for articles published between 1990 and 2023. Only randomized clinical trials (RCTs) and prospective studies were included. Studies involved patients who have been treated with dental implants with simultaneous or previously performed GBR.

Results and Discussion:

A total of 470 studies were identified after implementing the search strategy across the different databases. The results that have been reported may also be influenced by these factors.

Conclusion:

After a careful evaluation of the limited evidence included in studies, it can be concluded that GBR is a stable and effective technique of bone augmentation when compared to block grafting and distraction osteogenesis.

INTRODUCTION

Tooth replacement with dental implants has proven to be a dependable and effective method of dentition restoration. This can also make it easier to restore esthetically difficult areas like diastemata and irregular tooth positions.[1,2,3]

The immediate placement of dental implants after tooth extraction uses the alveolus before its resorption. After 6 months of tooth loss, the volumetric alteration in the maxillary and mandibular bones is described as being between 29 to 63% horizontally and 11 to 22% vertically[4] Numerous grafts like autogenous and allogeneic block grafts; autogenous, xenogenous, and alloplastic particulate grafts; alveolar crest expansion; and guided bone regeneration (GBR) have all been proposed for horizontal gain.[5] GBR promotes alveolar bone gain with predictable and consistent outcomes.[6,7]

However, the literature evidence is minimal, so this review was formulated to evaluate the treatment outcome differences between GBR and other techniques of bone augmentation for the placement of dental implants.

MATERIALS AND METHODS

Protocol and registration

This review protocol was developed following the Preferred Reporting Items for Systematic Reviews and Meta-Analysis 2020 Statement and the Cochrane Handbook. The review’s central question was as follows: What is the treatment outcome of using GBR for bone augmentation for the placement of dental implants?

Eligibility criteria

A PICOS criterion was developed to aid in the search strategy and selection of which studies should be included in the review. PICOS formulated for the review is as follows:

• Population (P) – Patients undergoing bone augmentation for the placement of dental implants.

• Intervention (I) – GBR using both resorbable or unresorbable membranes.

• Comparison (C) – Any other technique of bone augmentation.

• Outcome (O) – Changes in bone levels before and after augmentation and loading of dental implants.

• Study Design (S) – Original studies (randomized and nonrandomized controlled trials).

This review excluded animal studies, in vitro studies, finite element analysis studies, case reports, pilot studies, conference papers, and editorials.

Search strategy and study selection

A systematic search of the following databases was conducted to identify all peer-reviewed studies published from January 1990 to November 2023 that were relevant to the review’s question: PubMed, Google Scholar, Cochrane CENTRAL, Scopus, Web of Science, CNKI, Ovid, Baidu Scholar, Scielo, and LILACS.

Data extraction

The extracted data are summarized in Table 1.

Table 1.

Characteristics table

Author; Publication Year; Journal	Study location, design, and setting	Groups, Sample size	Assessment method and outcome measurements	Results
Chiapasco et al.; 2004;[9] Clinical Oral Implants Research.	Randomized controlled trial.	Sample size - 21 (9 males, 12 females; median age - 39.8 years) Group 1-11; Vertical GBR with e-PTFE titanium reinforced barriers and particulated autogenous bone taken from intraoral sites.	The measurement of peri-implant bone resorption was accomplished by comparing periapical radiographs obtained right after implant placement, at the prosthetic loading period and annually for three years.	No significant difference in the bone resorption levels between both the groups.
Amorfini et al.; 2014;[10] Clinical Implant Dentistry and Related Research.	Single center, spilt-mouth, two-parallel armed (1:1 ratio) randomized controlled trial.	Sample Size - 16 Group 1 - Corticocancellous iliac block Allografts were utilised in this group. After a full thickness flap elevation, implant beds were prepared using a teeth-supported stereolithographic guide and all the implants were placed without passing through the guide. After implant insertion, the graft procedures were performed. Group 2 - Conventional GBR technique.	Following a 1-year healing period from the definitive prosthesis delivery, a CBCT evaluation was performed to evaluate the stability and volume of the augmented areas.	The treatment changes were not significant when saline solution was used but was significant when rhPDGF-BB solution was used.

RESULTS

Study selection

A total of 470 studies were identified after implementing the search strategy across the different databases. The PRISMA flow chart [Figure 1] depicts the selection process.

Figure 1.

PRISMA diagram outlining the article selection process for the review

DISCUSSION

Before implant placement, a deficiency of either horizontal or vertical bone in the implant sites must be addressed as it may result in serious clinical problems.[8]

In the included studies in the review, Chiapasco et al. compared GBR with DO, and Amorfini et al. compared GBR with block grafting.[9] Amorfini et al.[10] showed that there was no significant difference in the median bone volume in both groups 1 year after loading and observed that there was no significant difference. Chiapasco et al. showed that the bone resorption was less and the bone level was more stable at the time of placement and 1 year after loading in the DO group.[9]

The majority of the studies reporting on the use of GBR required minimal bone augmentation for dehiscence or fenestrations, whereas there are studies reporting on the use of block grafts.[11]

It has been shown that bone regeneration is a very reliable method. Therefore, research is needed to determine the kind of material that produces the best results in terms of both bone quantity and bone quality.[12]

Strengths and limitations

The small number of studies and small sample sizes in the studies that were included for the qualitative analysis constitute a significant limitation of this review, and the method of measurement in the included studies was different in both studies.

CONCLUSION

After a careful evaluation of the limited evidence included in studies, it can be concluded that GBR is a stable and effective technique of bone augmentation when compared to block grafting and distraction osteogenesis. Thus, studies with better quality methodologies, greater sample size, and longitudinal follow-up are required to assess the treatment outcomes of GBR.

Conflicts of interest

There are no conflicts of interest.

Funding Statement

Nil.