Advantages

Fabric Construction

There are two general types of fabric construction: the woven and knitted. The commercial prostheses consist of 3 groups: woven, knitted and velour.

Woven Fabrics

1. Rigid

2. Used in repair of thoracic aorta, ruptured abdominal aortic aneurysms and patient with coagulation defects.

3. Less tendency to undergo dilation and deformation over time.

4, Low permeability, thus reducing bleeding at interstitial region.

Knitted Fabrics

1. Possess pores that vary in size, allowing the alteration of water permeability of the knitted prostheses.

2. Easier to handle than woven fabrics.

3. Used in abdominal aorta, iliac, femoral and popliteal vessels.

Velour Fabrics

1. Developed to improve healing.

2. Ability to create a rougher fabric surface that would improve the anchorage of the initial thrombotic matix and during surgery, minimize blood loss.

3. Porous feature, thus facilitating the growth of perigraft tissue in the graft.

4. Structure ability to retain cellular blood constituents and also promote growth of a fiber matrix.

Now, let's move on to synthetic graft:

Synthetic Grafts

Ideal Properties

1. Desirable biocompatibility.

2. Long term mechanical stability.

3. Prevent graft leakage.

4. Stress without failure.

5. Capable of withstanding long term hemodynamic.

The 3 main types of biomaterials used in production of synthetic grafts are Teflon, Dacron and Nylon.

Teflon

1. High elastic capacities

2. Long life.

3. Low thrombogeneity.

4. Exceptional physical & chemical properties.

5. High performance expectancy

    - 10 years, failure - 21%

    - 15 years, failure - 30%

    - 40 years, failure - 44%

Dacron

1. Biocompatible, resilient, flexible, durable & resistant to biodegradation.

2. Excellent conductors.

3. Resist process of haemodialysis (seal quickly after being punctured)

Nylon

1. Mechanical properties similar to Teflon/Dacron.

2. High elasticity, necessary for proper function & mobility as part of the vascular system.

Here, we will be discussing about biological graft:

Biological Vascular Grafts - Autograft, Allograft, Xenograft

Autograft

1. "Gold Standard" for Anterior Cruciate Ligament(ACL) reconstruction due to less chances of rejection.

2. Greater chance of fusion success than allograft.

3. Lesser risk of disease transmission than allograft.

Allograft

1. Prevents donor site morbidity.

2. Reduces surgical time.

3. Smaller incisions.

4. No weakening of extensor and flexor apparatus. 

5. Safer alternative to patient with higher risk of complication under anesthesia, given slower surgical time.

Xenograft

1. Potential solution that could saves thousands of patients under waiting list.

2. Animal organ, probably from baboon or pig that are genetically modified to resemble human to reduce chances of rejections.