Guided bone regeneration (GBR) Periodontal treatment

Guided bone regeneration (GBR) covers a bone graft with a barrier membrane that keeps soft tissue cells out of the defect, so bone-forming cells from the surrounding jaw can fill it. Soft tissue complications, including membrane exposure, followed 16.8% of GBR procedures in a meta-analysis.

Elegant woman poses in white shirt indoors, photo for Guided bone regeneration (GBR)

Step by step

The gum is opened over the thin or missing bone.
Graft particles are packed into the defect, often the patient's own bone mixed with bovine mineral.
A membrane is placed over the graft and, when needed, held with small tacks.
The gum is closed over the membrane without tension.
Bone fills the protected space over the following months.
A non-dissolvable membrane comes out in a short second procedure.

How does guided bone regeneration work?

Guided bone regeneration works by keeping soft tissue out of a bone defect so bone can fill it. An occlusive membrane over the defect blocks cells from the gum and connective tissue, and bone-forming cells from the surrounding jaw move into the protected space. The graft particles beneath hold the space open and give new bone a scaffold.

The membrane has to stay covered by gum while the bone matures. In a meta-analysis of regenerative procedures, new bone around implants was 6-fold greater when the membrane stayed covered. Around natural teeth, the same barrier principle is called guided tissue regeneration, and exposure had a minimal effect there. Implants placed in regenerated bone survive at rates comparable to implants in native bone. Ridge augmentation and periodontal regeneration use this principle.

What membranes are used in guided bone regeneration?

GBR membranes are either dissolvable collagen or non-dissolvable PTFE and titanium.

Membrane	Dissolves	Notes
Collagen	Yes	Often porcine; no removal surgery
Dense PTFE	No	Removed in a second procedure
Titanium-reinforced PTFE	No	Removed in a second procedure; used for vertical defects
Titanium mesh	No	Rigid space-maker; larger vertical gains and more complications

At Cambridge University Hospitals, dissolvable membranes are the usual choice, and non-dissolvable ones are rarely used. Non-dissolvable membranes come out in a small follow-up operation after 6 to 8 weeks. In a randomized trial of vertical GBR, titanium-reinforced PTFE membranes stayed in place for 6 months. Membrane fixation with tacks was weakly linked with more vertical gain in a meta-analysis. Bone graft materials covers what goes under the membrane.

How often does a GBR membrane become exposed?

Exposure and other soft tissue problems are common after GBR, and membrane type made no significant difference in a meta-analysis.

Barrier	Complication or exposure rate
Resorbable membranes	18.3%
Non-resorbable membranes	17.6%
Conventional titanium mesh	19.9%
Custom titanium mesh	15.2%

Counting exposure, wound opening and acute infection together, the overall rate was 16.8%. Soft tissue problems appeared between 1 week and 6 months after surgery. Mesh exposure did not differ significantly by mesh type, graft material or an added absorbable membrane. Soft tissue management by the surgeon is regarded as the main way to avoid these complications, including correct flap elevation and a tension-free closure. Patients who do not smoke report fewer complications. Bone graft failure covers what follows an exposure that does not heal.

What happens if a GBR membrane is exposed?

An exposed membrane is managed according to the size of the exposure and whether infection is present, from antiseptic rinses to removal of the membrane.

Exposure reduces the bone gained. Around implants, sites that stayed covered had 27% more reduction of the bone defect than exposed sites. Infection, graft exposure and too little new bone for an implant are listed among the later problems in an NHS bone grafting leaflet.

Call your periodontist if membrane material shows through the gum.
Call for pain or swelling that grows after the first few days, a foul taste, or fever.
Do not brush the surgical site until the surgeon advises; university instructions say to avoid it for at least 5 days.

When a graft is lost, the site can be grafted again after it heals. Bone graft recovery lists the normal course.

Can GBR be done with the implant?

GBR is often done at the same visit as the implant when part of the implant would sit outside the bone, and it usually adds no healing time.

A meta-analysis of GBR with collagen membranes found similar implant survival for simultaneous and later implant placement, and its authors recommend simultaneous placement when possible. Early placement after 4 to 8 weeks of gum healing lets the surgeon graft around the implant through intact gum, which makes the bone contour more predictable. Larger defects are grafted first, and the implant follows at least 4 months later. At post-extraction implants, bone grafting was more successful with immediate and early placement than with late placement. The dental implant process and immediate implants cover timing.

Questions

What is the difference between guided bone regeneration and a bone graft?

A bone graft is the material placed in a defect. Guided bone regeneration is the technique of covering that graft with a barrier membrane so gum tissue stays out while bone forms. GBR usually combines both, with graft particles under the membrane, so the terms often describe a single operation.

What is a PTFE membrane?

PTFE (polytetrafluoroethylene) membranes are non-dissolvable barriers for bone and tissue regeneration. Expanded PTFE is porous, and when it is exposed in the mouth that porosity raises the risk of early infection. Dense PTFE results in lower levels of early infection. In a randomized trial, dense PTFE was easier to remove than expanded PTFE, with identical bone results.

What is a collagen membrane?

A collagen membrane is a dissolvable barrier that covers a bone graft and resorbs without a second surgery. The most used dissolvable membrane at Cambridge University Hospitals is of porcine origin. GBR with particulate grafts and resorbable collagen membranes is effective for widening ridges. Cross-linked collagen membranes had an exposure rate about 30% higher than non-cross-linked ones.

Does GBR work for gum disease around teeth?

Around natural teeth, the same barrier principle is guided tissue regeneration (GTR), used in bone defects beside the roots. A Cochrane review found that GTR added 1.22 mm of attachment gain over flap surgery alone. GBR itself is used at implant sites and in toothless ridges.

How long does GBR take to heal?

Bone fills the space under the membrane over months. An NHS hospital grafts larger defects at least 4 months before the implant. Graft material can take 4 to 12 months to fill with the patient's own bone. When GBR is done with the implant, it usually adds no extra healing time.

What if my bone graft membrane falls out?

Call your periodontist. A membrane that loosens or shows through the gum is an exposure, the most common complication of bone grafting. Treatment depends on the size of the exposure and whether infection is present, from antiseptic rinses to removal of the membrane.

Sources

Reviewed by Steve Schadt, Director of IT and Medical Compliance: 25 years in dentistry, medicine and HIPAA compliance. Updated 2026-10-02. Checked against the sources listed. General information, not medical advice.

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