Bone Grafting 

Bone grafting, or augmentation, is a group of surgical techniques used to restore lost alveolar ridge volume for subsequent dental implant placement. After tooth extraction, bone atrophy progresses continuously. During the first 6 months, without additional measures, the alveolar ridge loses an average of 3.8 mm horizontally and 1.24 mm vertically; over 3–5 years, bone loss continues to increase.

If teeth have been missing for a long time, the deficiency may become so pronounced that direct implant placement is impossible. Bone augmentation for implant placement is a standard and predictable procedure. When the method is selected correctly and the protocol is followed, the overall survival rate of implants placed after augmentation is comparable to implant placement in native bone.

At Iskusstvo Clinic, the volume and method of bone grafting are determined based on CBCT data: three-dimensional measurement of the defect, including width, height, and extent; distance to the mandibular nerve and the floor of the maxillary sinus; and the condition of the remaining bone. Virtual planning makes it possible to calculate the exact volume of material required and plan simultaneous or delayed implant placement before the first incision is made. In cases requiring extensive reconstruction, such as severe atrophy or combined defects, the clinic’s maxillofacial surgeons are involved in the procedure.

Bone Grafting Materials

Autologous Bone, or Autograft

The patient’s own bone is the most biologically valuable material. It contains living osteoblasts, osteoinductive growth factors, including BMP-2, BMP-7, and TGF-β, and an osteoconductive mineral matrix. It is harvested from intraoral donor areas: the retromolar region, mandibular symphysis, or mandibular ramus. The volume of intraoral autograft is limited. If larger volumes are required, the iliac crest may be used as an extraoral donor site. The disadvantage is the need for a second surgical field.

Bio-Oss, Geistlich Pharma, Switzerland

Bio-Oss is a deproteinized bovine bone mineral and one of the most studied xenografts in implant dentistry. The deproteinization process completely removes organic components, eliminating antigenicity, while preserving only the mineral matrix with a three-dimensional porous structure identical to human cancellous bone.

Bio-Oss acts as an osteoconductive scaffold: osteoblasts grow into its pores and form new bone. Its key property is slow resorption over 3–5 years, which helps preserve volume throughout regeneration maturation and after implant placement.

Allografts, or Bone Bank Material

Allografts are processed human donor bone. They have an osteoconductive effect and are used for moderate defects and in combination with other materials.

Bone Grafting Methods

Guided Bone Regeneration, or GBR with Bone Material

This method involves filling the defect with Bio-Oss beneath a Bio-Gide barrier membrane. It is the method of choice for moderate horizontal defects, up to 3–5 mm. The membrane isolates the regeneration area from soft tissues, which contain fast-growing cells that compete with osteoblasts.

IDR Protocol, or Implant Driven Regeneration

This protocol involves implant placement simultaneously with filling the defects around it with bone material under a membrane. It is used for horizontal deficiency, meaning insufficient ridge width, when there is enough bone height to achieve primary stability. It reduces the total treatment time by 4–6 months compared with a two-stage approach, where augmentation is performed first and implant placement later.

Laminate Technique

Thin cortical bone plates, or laminates 1–2 mm thick, taken from an autograft or bone bank, are fixed to the atrophied ridge with microscrews or pins, forming a shell. The internal space is filled with a 50/50 mixture of autogenous bone and Bio-Oss, then covered with a Bio-Gide membrane.

The unique advantage of this technique is that it allows simultaneous increase of both ridge width and height, which is difficult to achieve with standard guided bone regeneration.

Block Autogenous Bone Grafting

A monoblock of cortical bone from the retromolar area or mandibular symphysis is fixed to the recipient site with microscrews. The gaps are filled with Bio-Oss and covered with a Bio-Gide membrane. This method provides the maximum augmentation volume when using intraoral donor sites. It is indicated for severe defects when neither guided bone regeneration nor the laminate technique can provide the required volume.

Treatment Sequence in Cases of Bone Deficiency

CBCT diagnostics → assessment of the defect volume → selection of method and material → professional oral hygiene and sanitation if necessary → augmentation surgery, with simultaneous implant placement using the IDR protocol if possible → healing period of 4–9 months → control CBCT → implant placement if it was not performed simultaneously → osseointegration for 3–6 months → prosthetic restoration.

Rehabilitation After Bone Grafting

The postoperative period after bone grafting is more difficult than after simple implant placement. Maximum swelling usually occurs within 48–72 hours. Antibiotic therapy is mandatory. A strict diet is required: soft food for 2–3 weeks, with no chewing on the operated side. Smoking is strictly prohibited for at least 2 weeks, as nicotine critically impairs vascularization of the graft. Sutures are removed on days 10–14.

Wound dehiscence is the most common complication. It may occur due to flap tension, early violation of the postoperative regimen, or smoking. In cases of minor dehiscence, local antiseptic treatment is performed, and part of the membrane may still function. In more significant cases, revision may be required.

This is why tension-free suturing is one of the most important technical aspects of the operation, and patient instruction is a mandatory stage of treatment.

Frequently Asked Questions

Bio-Oss or Autogenous Bone: Which Is Preferable?

Autogenous bone contains living cells and growth factors, making it more biologically active and allowing it to form bone regenerate faster. However, it requires a second surgical field, which means an additional incision and discomfort in the donor area, and its volume is limited.

Bio-Oss provides stable volume, does not require an additional intervention, and resorbs slowly. The optimal compromise is a 50/50 mixture: the biological activity of autogenous bone combined with the long-term volume stability of Bio-Oss. The choice of material is made by the surgeon based on the volume of the defect.

How Long Should I Wait After Bone Grafting Before Implant Placement?

For horizontal defects treated with the IDR protocol, the implant is placed simultaneously, and loading is possible after 4–6 months. With the laminate technique and block grafting, implant placement is usually performed after 6–9 months. The timing is confirmed by control CBCT: implant placement into immature regenerate should not be performed.

How Painful Is the Surgery?

The procedure is painless under anesthesia. During the first 3–5 days after surgery, pronounced swelling and moderate soreness may occur. If autogenous bone is harvested from the mandibular symphysis or retromolar area, additional discomfort may be felt in the donor site. All symptoms are controlled with prescribed medications.