Biomedical Engineering Reference
In-Depth Information
20.4
Nanotechnology for tooth regeneration
Tooth regeneration has long been the dental profession's aspiration; however, the combination of
tissue bioengineering along with the development of genetically designed trigger nanoparticles,
which are biomimetic with mineralized tissues, have begun to bear fruit in the manufacturing of
in vitro teeth.
Mao and coworkers, the pioneer researchers in the dental regeneration, suggested that the regen-
eration of teeth can be divided into several specific areas as follows
[46]
:
1.
Regeneration or de novo formation of an entire, anatomically correct tooth;
2.
Regeneration of the root;
3.
Regeneration of dental pulp;
4.
Regeneration of dentin that may either act as reparative dentin to seal off an exposed pulp
chamber or as a replacement of current synthetic materials;
5.
Regeneration of cementum as a part of periodontium regeneration or for loss of cementum
and/or dentin resulting from orthodontic tooth movement;
6.
Regeneration of periodontium including cementum, periodontal ligament, and alveolar bone;
7.
Regeneration or synthesis of enamel-like structures that may be used as biological substitute for
enamel;
8.
Remineralization of enamel and dentin.
For tooth regeneration, biomaterials have served primarily as a scaffold for (1) transplanted
stem cells and/or (2) recruitment of endogenous stem cells. It is indispensable for the regeneration
of tooth root, tooth crown, dental pulp, or an entire tooth. Nanomaterials, which can mimic surface
properties of natural tissues, have been highlighted as promising candidates for improving tradi-
tional dental tissue engineering materials. The various forms of tooth tissue engineering related to
nanotechnology and nanomaterials are described in the following sections.
20.4.1
Nanomaterials in biomimetic enamel regeneration
Enamel is the hardest material formed by vertebrates and is the most highly mineralized skeletal
tissue present in the body. Mature enamel is composed of 95
97% carbonated HA by weight with
less than 1% organic material. Mature dental enamel has a complex form, providing a striking
example of a highly mineralized structure exquisitely adapted to absorb essential mechanical and
abrasive stresses throughout the lifetime of the organism (
Figure 20.3
)
[47]
.
ligament (3) regeneration are cumbered. (B) GTR is a surgical procedure that utilizes a barrier membrane
which is placed under the gum and over the remaining bone to prevent epithelial down-growth (1) and
fibroblast trans-growth (2) into the wound space, thereby maintaining a space for true periodontal tissue
regeneration (3 and 4). (C) The use of bone grafts is a surgical procedure that replaces missing bone with
materials from the patient's own body (autogenous bone) or an artificial, synthetic, or natural substitute. Bone
growth may be stimulated by the grafts and new bone fills the defect which may provide support for the tooth.
Adapted from Ref.
[42]
. Reprinted with permission from Elsevier.
