spinner
Geistlich Blog header image
From 3D printing to artificial organs

Future regenerative dentistry

07.04.2015
share this article

Tissue engineering and regenerative medicine (TERM) is a highly multidisciplinary field. Integrative approaches are developed to overcome today's limitations in augmentation procedures.

Prof. Alan Herford | United States

Patients with defects due to congenital disorders, trauma or tumor removal often suffer from serious functional and esthetic deficiencies that strongly compromise their social lives. Current therapy options are highly invasive, associated with severe morbidity or are simply unavailable. However, the progress in technology has enabled advances. Promising techniques are now being studied1 that may shift the frontiers in regenerative dentistry and medicine. TERM techniques include:

  • Injecting cells into the damaged tissue, either with or without a degradable scaffold.
  • Growing a complete three-dimensional tissue to maturity in the laboratory and then implanting it into a patient.
  • Implanting a scaffold directly into the injured tissue and stimulating the body’s own cells to regenerate the tissue.
  • Introducing a gene encoding a therapeutic protein into cells, which can then express the target protein.
  • Cells + scaffold + growth factors

Three components are needed for successful tissue engineering: cells, scaffold or matrix and growth factors. Simply put, the cells grow along a physical scaffold, and specific growth factors stimulate cell activity and differentiation into the desired tissue.

 

Stem cells

Reconstruction of craniofacial and dental defects using mesenchymal stem cells avoids many of the limitations of both auto- and allografting. Clinical studies are underway using stem cells for alveolar ridge regeneration as well as long-bone defects.2 Dental stem cells from the pulp, periodontal ligament, and associated healthy tooth structure have shown promise in treating a number of diseases.

 

3D scaffolds

A scaffold is necessary to enable cell growth. It should contain growth factors such as Bone Morphogenic Protein (BMP), fibroblast growth factors, and endothelial growth factors to aid in stem cell proliferation and differentiation. Furthermore, it should provide nutrients promoting cell survival and growth. The scaffolds studied have included natural or synthetic, biodegradable or permanent materials.

 

3D printing of tissue

Technological advances in biomaterials, printer technology and computer-aided design allow replacement tissues and organs to be “printed”. The idea is to use patient data, such as from a CT scan, to first create a computer model of the organ. This model is used to guide the printer as it prints layer-by-layer a three-dimensional structure made up of cells and the biomaterials to hold the cells together.

 

Challenge: vascularization

Many challenges remain, however. For example, if an engineered tissue is placed into the body, it has to be vascularized quickly or the tissue will die. This presents a greater challenge in larger engineered tissues. The timing and appropriate doses of growth-factors are still under investigation.

 

Next evolution

Researchers are also developing engineered skin, which will help treat massive burns, chronic wounds and missing soft tissue in the oral cavity. Skin and cartilage substitutes are available through regenerative medical techniques, and laboratory-grown tracheas, blood vessels and other tissues have been implanted into patients. Other tissues that are at the early stages of engineering include heart valves as well as bladders. In fact, a whole bladder has been engineered and transplanted in a dog.3 The bladder appeared to be normal and demonstrated normal function.

Prof. Alan Herford

Prof. Alan Herford | United States

Oral and Maxillofacial Surgery
Loma Linda University

Your Comment

 Yes, I have read the privacy policy and agree to it.