Implant Placement Wıth Ilıac Graft

Iliac Graft for Implant Placement; Who is it for and Why is it Applied?

If there is insufficient bone height or thickness in the area where we want to place an implant, we first need to create a solid foundation. While local bone powders or small block grafts are sufficient for some patients, some cases require a much larger amount and higher quality of bone. It is in these advanced cases that the iliac crest onlay graft comes into play.

The iliac crest onlay graft is a procedure where bone blocks taken from the upper rim of the pelvic bone (iliac crest) are placed onto the jawbone, following the logic of "adding a floor." This way, both bone height and thickness are increased, resulting in a voluminous bone infrastructure suitable for advanced implant planning.

What is an Iliac Graft?

The iliac crest is the name we give to the upper rim of the pelvic bone (hip bone). This area is one of the most frequently used sites in the body for harvesting bone grafts because:

• It contains a large amount of bone,

• It contains both cortical (hard) and cancellous (spongy) bone,

• Its capacity for new bone formation (osteogenic potential) is high.

Therefore, in cases with advanced bone loss, bone taken from the iliac crest is prepared as an onlay graft and used as additional support for the jawbone.

What Does Onlay Graft Mean?

Onlay graft literally means "a graft placed on top." Instead of cutting and placing it inside the existing jawbone, we place additional bone on its top surface. You can think of it like adding bricks on top of a low wall to increase its height.

With the onlay graft application:

• The height of the bone can be increased,

• The width/thickness of the bone can be increased,

• The length, angle, and position of the implants planned afterwards can be made much more ideal.

Ultimately, the goal is to place the implants in a biomechanically safe, long-lasting, and aesthetically correct position.

In Which Situations is an Iliac Crest Onlay Graft Preferred?

The iliac crest onlay graft is generally used for patients with advanced bone loss, where sufficient results cannot be achieved with conventional bone powder or small block grafts. For example:

• Patients who have used complete dentures for many years and have severe bone resorption in their upper/lower jaws,

• Areas with large bone defects following accidents, trauma, cysts, tumors, or infections,

• Cases where a full-arch fixed implant-supported prosthesis is planned, but there is severe bone deficiency in both vertical and horizontal directions in the jaw,

• Situations where zygomatic implants are not considered as an alternative or a different treatment path is preferred.

In short: In severe cases where it is said "There is no bone, implant is difficult", the iliac crest onlay graft is an advanced surgical method that can reopen the door to fixed implant-supported teeth.

How is the Procedure Performed?

The procedure is mostly performed in a hospital setting, under sterile conditions, and often under general anesthesia:

1. Harvesting bone from the iliac crest region:
   A small surgical incision is made on the upper rim of the hip bone, and the necessary amount of bone is removed in blocks or pieces.

2. Preparing the jaw area:
   The gum is lifted in the jaw area planned for the implant, the bone surface is stimulated for bleeding (vascularized) and prepared to facilitate the fusion of the graft.

3. Placing the onlay graft:
   The harvested bone blocks are fixed onto the jawbone using mini screws or plates. Additional bone powder can be applied around the area if needed.

4. Healing process:
   Typically, 4–6 months are waited for the graft to fuse with the jawbone and for the new bone volume to mature.

5. Implant stage:
   Once sufficient bone volume and quality are achieved, the planned number and size of dental implants are placed.

What are the Advantages?

The most important advantage of the iliac crest onlay graft is that it provides the opportunity to gain a large amount of bone. In addition:

• It creates a biological foundation closest to natural for implants,

• It provides a durable infrastructure for extensive restorations like full-arch fixed prostheses,

• It provides three-dimensional volume increase in both vertical and horizontal bone losses.

Especially in cases where it is said "bone is too little, no implant," with a properly planned iliac crest onlay graft, implant treatment can become possible again.

Disadvantages and Points to Consider

This technique is an advanced surgical intervention and is not a simple method routinely recommended for every patient. Some disadvantages and risks include:

• There are two surgical sites: both the hip area and the inside of the mouth,

• There may be temporary pain, sensitivity, discomfort while walking in the iliac crest area,

• Complications such as infection, partial resorption of the graft, or failure to fully integrate may occur,

• The healing process is a period that requires more time and controlled follow-up compared to small local grafts.

Therefore, the iliac crest onlay graft is a treatment that must be planned with the correct indication and by an experienced surgeon.

Conclusion: A Powerful, Yet Selective Option in Severe Bone Loss

The iliac crest onlay graft can provide a strong infrastructure for fixed, implant-supported teeth even in patients with advanced bone loss. However, for success, the following are crucial:

• Detailed clinical examination and 3D imaging (CT/CBCT),

• An experienced oral and maxillofacial surgeon,

• The patient carefully following the healing process, check-ups, and care recommendations.

From the perspective of patients with major bone loss, the iliac crest onlay graft is an advanced surgical tool with the potential